{react} Magazine NEPG Issue

NEPG x {react} front cover.pdf

Science by Newcastle Students blogs.ncl.ac.uk/react

Issue 13 2020 {react}

The North East Postgraduate (NEPG) Conference is one of the largest annual student led biomedical sciences conferences in the UK. Historically, the conference has been hosted in Newcastle, at a number of the city’s key landmarks including the University of Newcastle, the Great North Museum, and the Newcastle Civic Centre. At a time when many conferences have been cancelled, NEPG has taken the bold move to take place online—allowing participation of delegates from all over the globe.

Following up on conversations had across the nation and worldwide, the theme of this year’s conference is diversity, with a panel discussion on diversity and inclusion in science to be held.

Incidentally this year’s conference is set to be the most diverse scientifically, with the largest range of topics being addressed in the conference’s history.

This special issue of {react} magazine present our pick of the many interesting research projects that are being presented at the conference, ranging from new discoveries in diabetes, to artificial corneas. Postgraduate research drives academic research, and I’m delighted to be part of NEPG this year.

As always, we hope you enjoy this issue of {react}, and hope that it inspires you in your own research, and to consider getting involved too!

AA 2020

Want to edit, organise or design this magazine? Get in touch!

THE TEAM EDITOR: Adam Azzi LAYOUT: Janire Castellano-Bueno

react.mag.team@gmail.com

SUB-EDITORS : Sammy Waite, Elizaveta Olkhova, Emily Graves, Kate Yukhnovich, Nathan Kindred BLOG MANAGER: Terri Lau

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Contents The Case for ’Getting Involved’ 4 Metal-Organic Frameworks as 6 Drug Delivery systems .

Algae—Our Waste is Their Food 9

Get involved Extracurricular activities can be beneficial to your PhD

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Using Artificial Intelligence to 12 Inform Clinical Decision-Making .

Glucose Metabolism and Beta- 14 Cell autophagy .

Silk Can Weave Our Future 17 Mucus: An Effective Solution to 20 a Sticky Problem o

AI Used in hospitals sooner than you think

Silk Ancient material gets new lease of life.

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Developing Seaweed Biomass 24 as a Biofuel Feedstock .

Alginate in Corneal 28 Tissue Engineering .

Corneas Making them from scratch

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OPINION

The Case for “Getting Involved” Adam Azzi Nobody in academia is free from the pressure to work more – the flexible nature of the wet lab in particular can lead to you working long hours – sometimes in a counterproductive way, somehow eating all the hours of the day, and all the days of the week. During the course of a postgraduate degree there is a multitude of opportunities to take advantage of that you might brush aside in favour of laser focus on work that contributes to your thesis. This seems like common sense; there exists this pervasive idea that to succeed in academia requires this absolute devotion to the lab bench.

That being said, there’s no doubt extracurricular activities “look good on the CV” - especially if you plan to exit academia but could it even help during your PhD, and further down the line in an academic career too?

Dr. Richy Hetherington is the skills development coordinator of Newcastle

University’s Faculty of Medical Sciences, and champions “getting involved” for all postgraduate students. He led a project that interviewed the previous organising committees of the NEPG, and some of the key findings are laid out in this short piece.

One of the main benefits was found to be gaining new skills – both soft skills and those relevant to an academic career: running a conference involves many skills that you don’t exercise day-to-day as an early career researcher.

As PhD students we are technically in charge of our projects, but in general our work takes a long time, with large conclusions being made up of incremental gains over months and years. We also have the safety net of our supervisors.

Organisers of the conference were in charge from day one, and forced to make comparatively quick decisions: Where was the conference to be held? Who should be invited to speak? What research themes should be involved?

Organising NEPG relied on having a team that met months before the conference, agreed on who was to execute certain jobs, and then actually do the tasks planned. At some point tasks were delegated – something we don’t have much experience of as postgraduate students, unless we supervise an undergraduate student. These are all skills that are part of being a successful PI - so clearly relevant to anyone planning to have an academic career.

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procrastination’. Quite often we judge ourselves for that weekend we spent watching Netflix, but time away from the lab is important. Knowing that time was spent doing something ‘productive’, something that we can even put on our CV fulfils the dual role of being enjoyable and being useful.

As well as ‘CV skills’, the organisers also gained valuable experiences. As researchers we are all familiar with the difficulty of publication – articles can be submitted and resubmitted multiple times before being accepted. Frustrating as this is, rarely are we put in a position where we ourselves are forced to accept – or reject – someone else’s work. NEPG committee gave the organisers a safe environment to exercise their skills of critical evaluation, and also the responsibility of maintaining the direction and academic integrity of the conference.

Another valuable experience was the feeling of completing their tenure as organisers. Having spent the best part of a year organising the conference, once it’s over the next cohort of organisers takes over. As postgraduate students we aren’t always fortunate enough to conclude our work within the timeframe of our degree, with work often carried on by the next student. Could this experience of ‘letting go’ help us move on in some way when leaving our work behind?

Aside from the skills and experience picked up, some of the organisers found organising NEPG to be a form of ‘helpful blogs.ncl.ac.uk/react

That element of being enjoyable is not to be underestimated either. Previous organisers were found to have close-knit committees that bonded quickly as they got down to the task of setting up the conference. Social interaction is something that can be lacking sometimes as a postgraduate student, especially in small labs, or in relatively remote corners of the campus. Coming straight from undergraduate studies can be a bit of a shock sometimes - getting involved in extracurricular activities can harken back to a more vibrant, social time.

The final take-home from interviewing previous organisers was the feeling of achievement when the conference was successful. Especially for PhD students, the projects we undertake can wind on forever, often not even concluding after 4 years of study, especially if the results are to be published. In contrast, the immediate, tangible achievement of pulling off the largest student-led conference in the UK is something to be treasured, and a worthy jewel to add to the crown of the PhD. We all feel the call to spend that extra hour working towards our thesis, but as previous experience has shown, everyone benefits from getting involved in something extracurricular – and those benefits can have a direct impact on our academic work, and future career.

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Metal-Organic Frameworks as Drug Delivery Systems Leire Celaya Azcoaga - University of the Basque Country Nowadays, a number of drug delivery systems (DDS) are being used and developed aiming to administer a molecule, or set of molecules, with pharmaceutical functions into the body. Their aim is to achieve a therapeutic effect while controlling the time, rate and specific place of the drug´s release. In order for the pharmaceutical released by the DDS to do its actions as effectively as possible, they have to: i) be introduced into the body without causing adverse effects, ii) be transported to its site of action, iii) interact with specific receptors or extracellular walls or be incorporated within the cell themselves, iv) release the cargo in a controlled manner, if possible, triggering it by the application of an external stimulus, and, v) be disassembled into fundamental components that need to be metabolized without causing adverse effects.

The most common form of

medication is the pill Throughout history, the most common form of medication administration has been the pill device. Though the concept of pill administration is pretty easy to understand, this form of drug delivery system may not be adequate for certain pharmaceuticals such as those which break down in the 6

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stomach before reaching their site of action (e.g.: insulin). Therefore, research to find alternatives to conventional drug therapy methods has been carried out during the last few decades. Some of these systems have shown to improve the therapeutic effect of the drugs, reduce their toxicity and increase patient compliance and convenience.

In this research field, organic and inorganic biomaterials have been widely used as safe drug carriers, although both show some drawbacks regarding their nature. For instance, organic-based DDSs (e.g. chitosan) show an easy degradation behaviour which causes a burst release of the drug while the inorganic-based ones (e.g. hydroxyapatite) tend to show small drug loading capabilities. For these reasons, the development of DDSs systems based on a material that could combine the ample functionalities of polymeric compounds and the robustness and porosity of inorganic systems would suppose a clear advantage to synergistically combine the benefits shown by inorganic and organic materials, while minimizing their drawbacks. Within the narrow scope of materials that can meet all these key characteristics, Metal-Organic Frameworks (MOFs) have emerged as an amazing family of porous materials that show an intermediate inorganic and organic nature combined with a highly tuneable porous structure. blogs.ncl.ac.uk/react

Adapted from An et. al, CCR (2019)

The five incorporation strategies using MOFs Then again, what exactly are metal-organic frameworks? According to IUPAC, MOFs are inorganic-organic coordination compounds extending through repeating coordination entities in either 1 dimension or 2 or 3 dimensional structures exhibiting potential voids with well-defined volume, pore window and connectivity. More precisely, MOFs are a class of porous hybrid materials consisting of inorganic clusters and organic ligands. The way these two pieces assembly together is of great importance as their final structure and, therefore, their porosity depends on it.

It should be underlined that these materials are intended to work within our body and, therefore, they must fulfil certain features: ■ Composed of biocompatible/ biodegradable materials that show nontoxicity at different levels (i.e. inorganic ions, organic linkers, solvent…).

■ Structural control over size and shape of drug cargo-space along with a welldefined scaffolding and/or surface blogs.ncl.ac.uk/react

modifiable functionality. These are essential for the design of the drug loading, encapsulation or chemical anchoring strategies into or onto the MOF material.

■ Sufficient chemical stability in biologically relevant media to reach the target location/organ where the drug needs to be released.

■ Lack of immunogenicity i.e. avoid the use of materials which could provoke an immunological response.

■ A controlled release mechanism, when possible triggered by an external stimulus (e.g.: pH, magnetism) for improving dose effectiveness.

Once the selected MOF meets all of the abovementioned requirements, the next step would be to know or select the incorporation strategy of the pharmaceutical cargo. To date, 5 different strategies have been encountered, all of which can schematically be seen in Figure 3.

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RESEARCH 1) Surface attachment This first method consists on the adsorption of biomolecules on the surface of MOFs via weak interaction forces such as Van der Waals, p-p and hydrogen bonding. On the one hand, surface attachments don´t rely on specific pore size, since the attachment takes place at the surface of the particles, a fact that enables the use of a broad number of different MOFs. Unfortunately, and though it is quicker and easier to carry out, this method leaves the attached molecule highly exposed to its surroundings which may lead to leaching problems (detachment of the adsorbed molecule by way of its surroundings before reaching its site of action).

2) Covalent binding Aiming to overcome said leakage problems, this method proposes covalently binding the biomolecule onto the MOF´s structure, which usually results in a more complex synthetic pathway.

3) Pore encapsulation In this strategy the controlled selection of the proper microporous to mesoporous structure can be used to selectively trap different kinds of substrates. By accommodating functional molecules inside its pores MOFs ultimately provide a protective coat that can improve stability under harsh or biologically incompatible environments, ultimately decreasing the leaching issue8.

4)In-situ encapsulation During the in-situ encapsulation process, the encapsulation and the synthesis of the MOFs both occur at the same time, with the MOF growing around the molecule to be 8

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encapsulated. Thereby, this technique allows the inclusion of larger molecules which may exceed the size of the pore openings while also working as a protective coating.

5)BioMOFs In this case the MOFs are created by using active pharmaceutical ingredients (APIs) or endogenous molecules as their organic linker. This strategy, along with the one before, shows one great disadvantage: the need for mild synthesis conditions which greatly decreases the number of MOFs that can be used.

All in all, MOF functionalization through the abovementioned techniques has demonstrated the potential of MOF´s crystal -chemistry as a powerful tool for the specific, controlled and long-term delivery of drugs. Having said that, it is important to bear in mind that several challenges remain to be solved.

Although incorporation of various bioactive molecules within the MOF´s structures have been achieved, each and every single one of them has showed its own advantages and limitations.

In short, MOFs are promising candidates for the design of new and improved drug delivery systems, although further research is needed to understand the underpinning interactions established between the drug molecules loaded within the pores or onto the surface of MOFs. One of the most promising approaches to this end is multivariate encoding, which benefits from the internal surface decoration with different motifs, and allows modulating the host-guest interactions. There is, however, still room for improvement, and I hope to pursue this in my future work. blogs.ncl.ac.uk/react

Algae – Our Waste is

Their Food Aya Farag - Sheffield University Algae... these fascinating little creatures have some impressive capabilities that are definitely worth exploring.

Algae are a very diverse and large group of microscopic and macroscopic eukaryotic organisms that carry out oxygenic photosynthesis. Algae are ubiquitous in nature as they inhabit a wide variety of terresterial and aquatic (marine and fresh water) ecosystems which is the reason why

they are extensively studied by researchers in different fields. Another reason for studying different algal species was their fascinating capability of being useful in different fields such as food and health supplements production, aquaculture support, pharmaceuticals and biofuel production as well as waste water treatment which will be the scope of this article.

The steps involved in microalgal identification blogs.ncl.ac.uk/react

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RESEARCH Water scarcity represents a global concern; less than 1% of the water on earth is directly available for human use from which 70% is used in agriculture. Therefore, water pollution with various wastes, together with a growing population, becomes a major threat. Landfill leachate in particular is a complex, challenging and costly wastewater type to treat. It may pollute ground water as well as surface water. Landfill leachate contains various types of pollutants which may be categorised into four groups: dissolved organic matter, inorganic macrocomponents, heavy metals, and xenobiotic organic compounds. The release of leachate to waterbodies in the environment without treatment has serious deleterious effects including partial oxygen depletion from the waterbodies it is released into, which in turn causes serious changes in the bottom fauna and flora as well as ammonia toxicity.

Besides, several bioassay tests indicated that untreated leachate may induce cytotoxicity, genotoxicity, carcinogenicity or oestrogenicity as a result to the synergistic, additive or antagonistic effects of the contaminants present in it. Moreover, several hazardous compounds are found in untreated leachate, many of which are not yet identified. It became a necessity, beacause of the previously mentioned reasons and because of the fact that landfill sites continue producing leachate for hundreds of years even after closure, to approach sustainable ecofriendly and economic methods for landfill leachate treatment before discharging it into the environment. One of the most promising technologies in this regard is the

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application of microalgae for landfill leachate treatment.

Although there are various studies on the possibility of treating wastewater using microalgal biomass, a process known as phytoremediation, there are fewer studies regarding the biotreatment of landfill leachate using microalgae. This might be attributed to the complex nature of landfill leachate and its possible toxicity to living organisms. Nevertheless, microalgae have shown some promising results in this regard which make them possible candidates in effective leachate treatment.

A key step in this process is the selection of suitably tolerant microalgal strains.

Although the capability of algae isolated from landfill leachate itself is usually better than other adaptive strains for the leachate treatment, the research on indigenous microalgae inhabiting and growing in landfill leachate is limited. An even lower number of studies used molecular biology tools to distinctively and unequivocally identify the indigenous algal strains inhabiting the landfill leachate with the potential of being powerful candidates in further phytoremediation processes.

In addition to green microalgae, cyanobacteria (blue-green algae) also represent a valuable and effective source for wastewater treatment as well as nitrified landfill leachate treatment with the advantage of high biomass production when cultivated in wastewater and landfill leachate. Therefore, having the ability to reveal more indigenous strains might allow the possibility of using them in future biotreatment of wastewater and landfill leachate, as well as biomass production blogs.ncl.ac.uk/react

Landfill leachate sample in the middle from which six different strains were isolated: four green algae and two cyanobacteria which might be of several uses as biofuel, biodiesel, or feedstock.

In this study, four green microalgal strains and two cyanobacterial strains isolated from a landfill leachate treatment site in Chesterfield, UK were cultured and purified. Five primers were used to identify the rDNA in the four green algae isolates, in addition to the 16S primer for identification of the cyanobacteria isolates.

The study, therefore, provides more accurate identification of these strains with an evidence of a biodiverse environment of indigenous leachate-inhabiting green algae and cyanobacteria, results are summarised in Figure 1, which might allow the future possibility of using them as powerful landfill leachate and wastewater treatment candidates. blogs.ncl.ac.uk/react

The identification revealed two strains of Chlorella vulgaris MT137379 and Chlorella vulgaris MT137382, one strain of Chlorococcum sp. MT152906 and one strain of Scotiellopsis reticulata MT151679. Two strains of cyanobacteria were also identified using PCR amplification of DNA sequences from the 16S rDNA region. The cyanobacterial strains were identified as Phormidium autumnale MT152907 and Phormidium autumnale MT153248. This research sheds some light on the microalgal and cyanobacterial diversity in a local landfill leachate treatment environment.

Uncovering the species that make up this diversity might provide possible candidates for a future biological cost-effective and eco -friendly landfill leachate treatment approach.

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RESEARCH

Using Artificial Intelligence to Inform Clinical Decision-making Nehal Hassan - Newcastle University Although “learning” has been thought to be a cognitive skill of humans, a new type of learning not related to humans or even living creatures was introduced sixty years ago; it was called "machine learning." But how do machines learn?

Humans learn from their own experiences and from those of others. Machines can learn in a similar way; they can use data from the past about whether an event occurred or not, for example, and based on current information predict whether this event is likely to occur in the future.

Machine learning is a subset of artificial intelligence. Paraphrasing, artificial intelligence is how we make machines simulate human decisions and behaviours in a particular situation, like risk assessments, for example. While machine learning involves the use of neural network algorithms (advanced statistical calculations) that are developed based on previous information to provide a calculated outcome.

of big data and machine learning can help predict the likelihood of diseases before they occur. These machine learning algorithms are expected to improve patient safety and reduce healthcare costs.

Additionally, it can save clinicians’ time for more critical patients, which can reduce the burden of clinicians’ shortage.

Real World Example - Infection and subsequent sepsis Microbes, such as bacteria, viruses, and fungi, can cause a life-threatening infectious condition known as sepsis. In Europe, mortality due to sepsis is estimated to be 38%. Sepsis is a rapidly progressive condition, with patients deteriorating within a few hours and needing intensive treatment. Due to the increasingly resistant nature of bacterial strains causing sepsis, empirical antibiotic therapy may be unsuccessful in a significant proportion of

Applications of machine learning are everywhere. Amazon, the world largest electronic shopping application uses machine learning to predict what you might be interested in purchasing when you visit their website (these predictions are based on your past purchases). Machine learning has multiple applications that impact our daily life. In healthcare, the use 12

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patients presenting with this condition.

Protecting individuals from infections is the best solution to reduce the incidence of sepsis and associated mortality. This is especially important for individuals with underlying risk factors for infection. These algorithms can guide clinicians’ decisionmaking and thereby help protect patients from developing sepsis.

My doctoral project focuses on developing a machine learning algorithm that can predict the likelihood of infections and subsequent sepsis in patients who undergo elective surgery. I use de-identified data of patients who had similar procedures and got infections in the past, taking into consideration their clinical relevance and utility, to teach the machine (electronic computer system) how to predict infections in patients who will undergo an operation before their procedure. Although there are already scores for calculating the risk of infection, machine learning algorithms have shown better predictive abilities compared to current conventional scoring systems.

However, we found that these algorithms have limitations; some have been trained using non-specific definitions for sepsis and can be misleading in sepsis prediction.

Some algorithms also neglect predictors that could influence the susceptibility and exposure of patients to infections, resulting in algorithms with low specificity or sensitivity. Accordingly, we aim to develop an algorithm that will have high sensitivity and specificity, and a predictive window long enough to allow clinicians taking measures to reduce the risk of infection.

The value of this work lies in its ability to develop an algorithm that will not only save money and resource for the hospital blogs.ncl.ac.uk/react

but, more importantly, patient lives.

Prediction of infections early can also reduce the length of a patient’s hospital stay, the use of medications (including precious antibiotics), antimicrobial resistance, and overall help improve the quality of direct patient care. We believe that this machine learning algorithm can guide clinicians with their decision-making and reduce the likelihood of adverse clinical outcomes. It can potentially flag patients at high risk of sepsis and potentially assist clinicians with their decision-making.

Predicting the likelihood of infections is only the beginning. Machine learning algorithms can guide screening, diagnosis and treatment options of a medical condition. They can also guide the choice of medications in terms of the personalised risk of adverse outcomes, a feature that makes machine learning algorithms part of the toolkit for patient safety. These algorithms do not only inform decision making by clinicians, but it can also support shared decision making which is made jointly by patients and their treating clinicians, making patients an active partner in their treatment plan.

This work is being conducted in collaboration with Newcastle Hospitals NHS Foundation Trust. We are currently carrying this work out at Newcastle University, but invite the opportunity to collaborate.

For more information please contact :

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Glucose Metabolism May Influence Beta-cell Autophagy and Survival in Type 2 Diabetes Amelia Williams - Newcastle University The history of diabetes mellitus Diabetes mellitus is a chronic disease in which the body does not produce enough of, or respond properly to, the hormone insulin which is synthesized in the pancreas. This results in increased blood glucose levels. Typical symptoms experienced by patients include excessive thirst, urination and hunger. Diabetes is a disease with a long-documented history, beginning with descriptions detailed in Ancient Egyptian papyri and treatments for reminiscent conditions being prescribed in 600 B.C. India. The term ‘diabetes’ was introduced by Aretaeus of Cappadocia, who practised in Ancient Greece towards the end of the Hellenistic age. In his description of the disease, Aretaeus noted its chronic nature, and the presentation of excessive thirst and urination in patients.

The observation of increased urination led Aretaeus to name the condition διαβήτης (diabetes), meaning ‘siphon’. In 1675, it was Thomas Willis who added the term ‘mellitus’ to the condition’s name, after noting that the urine of diabetic patients tasted sweet.

The pancreas was linked to diabetes in the 19th Century. It was Paul Langerhans who first discovered clusters of cells named the islets of Langerhans within the pancreas. Then, in 1889, the pancreas was associated with diabetes by 14

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Oskar Minkowski and Josef von Mering.

Minkowski and von Mering suggested that the pancreas released a form of ‘internal secretion’ that aided in the regulation of the metabolism of carbohydrates. This internal secretion was identified as insulin, secreted by the islets of Langerhans, by Frederick Banting, with Charles Best and John Macleod in the 1920s. Specifically, it is the beta-cells, within the islets of Langerhans, that secrete insulin.

Diabetes can be classified into two main categories; type 1 or type 2. In this article we will focus upon type 2 diabetes (T2D).

Type 2 diabetes T2D can be a debilitating condition, and is linked with secondary complications including high blood pressure. T2D is a global issue, with an estimated 10% of adults aged 25 or older living with the disease, with global incidence also increasing. There are several irregularities observed within the development of T2D, including; insulin resistance, impaired insulin secretion and obesity. Insulin resistance develops when cells do not respond to insulin in a normal manner, resulting in blood glucose levels remaining high. As a result, beta-cells attempt to compensate for the high glucose levels by secreting more insulin, which again, is not responded to by cells. T2D develops when blogs.ncl.ac.uk/react

Diagram of the process of autophagy the beta-cells cannot compensate for insulin resistance, which is characterised by betacell loss. However, the mechanism behind this loss is still unknown.

Beta-cell macroautophagy One mechanism that has been suggested to influence beta-cell loss in T2D is macroautophagy, which will now be referred to simply as autophagy.

Autophagy, in essence, is a cellular recycling process, which is visualised in the figure below. Autophagy involves the fusion of enzyme-containing lysosomes, to double-membrane structures, named autophagosomes. Damaged proteins and organelles contained in the autophagosomes are then broken down into simpler building blocks, such as amino acids, to aid in the preservation of cellular homeostasis, thus promoting cell survival. Autophagy is controlled by two signalling pathways, made up by many different proteins. The ‘AMPactivated protein kinase (AMPK) signalling pathway’ acts to induce autophagy, whereas the ‘mammalian target of rapamycin (mTOR) signalling pathway’ acts to inhibit autophagy. It is the interplay between these two pathways which ultimately decides when and where autophagy is induced, with a balance being required to prevent unnecessary cellular damage or demise. blogs.ncl.ac.uk/react

But how can we link the process of autophagy to T2D? As previously stated, beta-cells are lost in T2D to an as-yet unknown mechanism or mechanisms. It is known that autophagy promotes beta-cell survival in healthy beta-cells, however, more and more studies now propose that autophagy may, in fact, contribute to the beta-cell loss observed in T2D. Beta-cells act as glucose sensors, therefore in the context of T2D, it is physiologically relevant to assess the effects of glucose upon autophagy. Therefore, the main aim of our research was to investigate the effects of glucose metabolism on beta-cell autophagy, and to explore the signalling pathways involved.

Carrying out the experiments Insulinoma cells from rats, known as INS1E cells, were exposed to a variety of conditions to differentially stimulate glucose metabolism. These treatments included varying glucose concentrations, a glucokinase activator (glucokinase being an enzyme that stimulates the first step of glycolysis), an inhibitor of glucokinase (5thioglucose), and an inhibitor of mTOR signalling (Torin). To analyse the results of these treatments, we assessed the protein activation of a number of proteins involved in the mTOR signalling pathway.

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RESEARCH assessed were named ribosomal protein S6 (S6), protein kinase B (AKT) and extracellular signal-regulated kinase (ERK). We also assessed the conversion of a protein named LC3-I into LC3-II, as a measure of autophagy induction.

Our findings Firstly, we needed to assess the effects of glucokinase activation on LC3II conversion, and hence autophagy induction. We determined that LC3-II conversion was significantly decreased in cells treated with the glucokinase activator, compared to untreated cells. This suggests that elevated glucokinase activity, and hence glucose metabolism, negatively impacts upon autophagy.

We then needed to ask how glucose metabolism affects the proteins of the mTOR signalling pathway, which functions to inhibit autophagy. The first protein we assessed was the downstream mTOR signalling protein S6. We observed that glucokinase activation significantly activated the S6 protein, once again indicating an inhibitory effect of

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glucokinase activation on beta-cell autophagy.

To prove that glucokinase activation influenced the mTOR signalling pathway to stimulate autophagy inhibition, we once again assessed LC3-II conversion. We compared the effects of glucokinase activation on cells when the mTOR signalling pathway was inhibited or uninhibited. We discovered that inhibition of the mTOR signalling pathway prevented the inhibition of autophagy by the glucokinase activator. This suggests that the mTOR signalling pathway is influenced by glucose metabolism to negatively impact upon beta-cell autophagy.

However, could proteins signalling upstream of mTOR also be influenced by glucose metabolism to affect beta-cell autophagy? We studied the effects of glucokinase activation on the upstream mTOR signalling proteins AKT and ERK. By inhibiting both AKT and ERK signalling, we were able to determine that this inhibition did not prevent the decrease in LC3-II conversion caused by glucokinase activation. It was concluded that the effects of glucose metabolism on beta-cell autophagy were not, therefore, influenced by AKT and ERK signalling.

Conclusion T2D is a condition with a history spanning many years, however, there is still much about the disease that we have yet to discover. Through our research, we have learned that glucose metabolism does impact beta-cell autophagy, via the mTOR signalling pathway, which may then influence beta-cell loss in T2D. I highly encourage anyone with an interest in diabetes research to delve further into the literature and broaden your knowledge; you never know, you might make the next big research breakthrough! blogs.ncl.ac.uk/react

Silk Can Weave Our Future Vamanie Perumal - Indian Institute of Technology Silk has had a long history of supremacy in textiles. Not just an element of luxury, silk is a versatile material for modern engineering applications. The material, delicate and fragile as it may seem, has uses across tissue engineering, smart wearables, optical sensors and medical devices. Silk from spiders and domesticated silkworms have drawn significant attention from scientists. The material is obtained from the larvae of spiders and insects. The process by which a spider spins its web is considered to be similar to 3D printing, in which the fiber is produced by the arrangement of amino acids and drawn into long filaments. Silkworm cocoons are beautiful entities which protect the worm from different threats and environmental conditions. The cocoons are simultaneously tough and light. They act as a hard shell, a microbe filter, and also as a climate chamber. All things considered; silkworms have incredibly smart homes to live in!

With all the technological advances astronomists and astrophysicists have developed over the past century, human beings have a deep fascination with the existence or possibility of life elsewhere.

Silkworms have been sent to space by the Japan Aerospace Exploration Agency to

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understand the effect of space radiation on biomolecules and life processes.

Interestingly, silk thrives in space, owing to the fact that the material not only performs well in an extremely cold environment, but can in fact strengthen under these conditions. Since the stand-out properties of silk are its durable, strength and adaptability, it is no wonder that this classic material is used across all scopes of life.

Silkworms have been sent to space by JAXA Silk with Multiple Personalities The properties of silk largely depend on the species, rearing conditions, and degree of hydration. The complex structure and low cost of silk make it an incredibly lucrative material to work with. Silk is highly processable, meaning many configurations can be made out of it to generate a wide array of useful tools. In fact, if you look close enough, you can observe the uses of silk across many aspects of life. For example, this diverse material is used in biomedical engineering, regenerative medicine, diagnostics, wound healing, body armor, scaffolds, sponges, drug Issue 13 2020 {react}

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RESEARCH cosmetics. The cosmetics segment has been largely acquired by Givaudan, who have recently worked with Wella Professionals make Spider Silk shampoo. However, Givaudan is not the only manufacturer using silk in cosmetics. Other companies, such as Bolt Threads, Evolved by Nature, Kanebo and AM Silk, produce thousands of silk-based products per year.

Loom for weaving silk delivery, anti-counterfeiting, smart wearables. Silk fabrics are multifunctional with a good combination of mechanical, electrical and semiconducting properties, and would have utility in smart functional fabrics. For instance, they can be used in devices for audio reproduction which require robustness and response to magnetic fields. As silk is such a versatile material, it is utilised by many corporations around the world for simple, cost-effective solutions to day-to-day problems.

Adidas, one of the largest sportswear manufactures in the world, uses spider silk to make everything from shoes to dresses.

In fact, the silk of Bolt Threads was used in the official Biofabric Tennis Dress of Adidas. Clearly, silk has applications in many aspects of life, from plants, to medicine, to the trainers you wear to the gym.

Shortcomings of silk fibers Despite the clear commercial and scientific advantages of using silk, all materials have their limitations. Although silk has been shown to resist against very low temperatures, the material is vulnerable to

Let’s talk business about silk Beyond textiles and luxury commodities, today silk stands as a focal point of thriving tech-based businesses. Recently, many interesting ventures have arisen with ideas based on silk. One company, Cambridge Crops, has utilised silk to make edible silk coatings to prevent crops from perishing.

This use of silk may have significant positive environmental and socio-economic impacts due to a reduction in food wastage using natural, simple methods. Another popular application for silk is its use in 18

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Silk moth resting on a finger blogs.ncl.ac.uk/react

durable material for businesses to utilise, it is important that manufacturers assess the conditions the product will be exposed to and adapt accordingly How silk made me strong

Equipment for testing tensile strength of silk fibres thermal ageing at very high temperatures, meaning it is not suitable for use in such settings. In addition, elevated humidity levels and light may cause deterioration of silk, resulting in induced aging and yellowing, attack by microbes, and wrinkling. Manufacturers looking to use silk must remember this, and also be aware that microbial, oxidative and hydrolytic attack may cause silk to become brittle and lose its mechanical integrity. Therefore, although this is an adaptable, mostly blogs.ncl.ac.uk/react

As you can probably tell, I have a huge interest in silk. For my masters, I worked on creating novel composite materials using silk fibers. My studies revolved around finding the optimal combinations of silk fiber and matrices which give the desired properties. I feel extremely proud to have worked on a sustainable material and explore the possibilities of using silk in a technologically advanced society to meet applications of a smart world. The fabrication of silk composites is challenging, due to non-availability of established procedures and sensitivity of silk to chemicals and high temperature. I worked on developing a method to make a high-volume fraction silk composite with the entire fabrication being carried out at room temperature. I also focused on bringing out the best combination of two conflicting properties – the stiffness and ductility. Using a statistical approach, I tried to make a meaningful relationship among the properties and find the best trade-off solution. I had a brilliant time working on this project. This is largely because I was able to perform a mini survey on types of silk, their quality, and bought meters of silk threads. In fact, some of the silk and hemp cloth I bought for my project are leftover so I am going to stitch a shirt for myself to preserve the memory of my time working with silk, the most durable, luxury material I know to come from bugs.

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Mucus: An Effective Solution to a Sticky Problem Kyle Stanforth - Newcastle University Epithelia, Mucus, and Modelling the Digestive Tract The human body produces about 1.5 litres of mucus every single day (and even more when you have a cold!). That means over the course of your life, your body will produce enough mucus to fill an entire metro carriage, or - if you want to get technical - about 1.21 million cans of coke.

This mucus is present on many of the epithelial surfaces of the body. Epithelia are the continuous sheets of cells, often just one cell thick, which cover the external surfaces of the body. Not just the obvious external surfaces like the skin and the cornea, but also the lining of the lungs and the digestive tract – which form exchange surfaces between our insides and the outside world for the transfer of nutrients, gases and secretions.

Many of these surfaces are covered by mucus, which functions as a surface barrier, protecting the delicate epithelia from physical and chemical and microbial damage. The digestive tract and the lungs have a combined surface area of around 82m2 respectively – not far off a full-size badminton court. The complex structure of mucus has evolved to allow it to protect the underlying tissues, while still allowing the epithelia to carry out it’s essential exchange functions.

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My PhD project, working with Newcastle University and Aelius Biotech is all about mucus.

Aelius Biotech are a contract research organisation that works with food and pharmaceutical companies to research and develop new products, while reducing the reliance on animal testing.

Aelius Biotech have a range of in vitro models of the human digestive tract and have effectively replicated the functions of mucus in the gastrointestinal tract. This then allows the development of models which can simulate digestion and absorption at the same time. Without being able to properly model mucus function in the lab, it isn’t possible to mix whole digestive fluids with cell culture models without killing all of your cells. The focus of my PhD is to compare the specially engineered mucus, which Aelius Biotech have developed in house, with native mucus from the small intestine of pigs. The aim is to develop and validate a small intestinal absorption model complete with a functioning mucus layer. This model will then be integrated into Aelius Biotech’s patented model gut system, so that digestion, mucus permeation and epithelial absorption can be modelled right through the digestive tract, to give a world leading model of the digestive tract.

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But why is this all important?

How many people do you personally know that dislikes, or even still, is terrified of injections? Chances are, you can name a few and even then who wouldn’t prefer to take the drug as a tablet? Unfortunately, there are many pharmaceuticals in medicine that must be administered intravenously.

Simply due to the fact they are poorly absorbed in the small intestine - especially those that do not dissolve well in water.

However, sometimes an injection is not feasible or convenient, especially from a home setting, and often can cause patients’ distress. This leads to a reliance on oral administration, which in poorly absorbed drugs, results in a waste of pharmaceuticals or even an ineffective treatment. Models of the digestive tract can help accelerate and improve development of effective drug delivery models, creating solutions to these problems.

Generally, there are two types of model which are used to carry out this research, in vivo and in vitro. In vivo refers to studies done directly using the organism i.e. human or animal trials. These studies consider the complex biological systems involved in digestion and absorption, and to no surprise, human studies are the gold standard, as data will relate directly to human biology. However, despite their applications, in vivo research has several rather significant disadvantages: they are

time consuming, can cost a lot of money, require ethical approval and are subject to interindividual variability.

In vitro studies, on the other hand, are a type of study performed outside of living organisms in a controlled laboratory environment. These became a popular alternative to in vivo study due to their cost effectiveness, speed, lack of a requirement for ethical approval and much more control over variables. However, the degree of how well in vitro gut models relate to real life scenarios, i.e. the physiological relevance, varies with system complexity, and though there have been dramatic improvements in modelling digestion through the digestive tract in vitro, modelling of the absorptive phase is a much more difficult task.

The Problem: Absorption Models and Mucus Physiological relevance of in vitro gut models is vital to make sure experimental data gained will relate back to what will happen in the real world. Achieving this with the absorptive phase of the small intestine is a difficult task. In vivo, the small intestine requires a vast number of specific cellular transport mechanisms to promote nutrient absorption. This means that any in vitro model it is crucial to use the correct cell types to replicate an accurate absorption model. Currently, in vitro models of absorption range from very simple, cell free models, to complex, 3D,

The structure of MUC2, the mucin that makes up small intestinal mucus. The VNTR region is heavily glycosylated, as shown by the lines. The other structures are functional domains which help the mucins interact with each other.

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RESEARCH meaning mucus is absolutely necessary for accurate evaluation of in vitro absorption models.

cellular absorption models. Despite high end, cellular in vitro absorption models being as physiologically relevant as they’ve ever been, they still lack an incredibly important component, a mucus layer – this is where my PhD comes in.

Mucus is a negatively charged hydrogel made up of mucin glycoproteins. These are heavily glycosylated, meaning they have very long carbohydrate side chains. This unique property of mucins, along with their protein domain structure, allows them to polymerise, hydrate dramatically and form gels.

In the small intestine, mucus is made up of a mucin called MUC2. Upon gel formation the MUC2 mucus layer on the surface of the small intestine forms pores of around 200 nm in diameter. These pores allow particles smaller than 200 nm to traverse the mucus layer and size exclude larger particles. With no mucus layer, particles larger than 200 nm will easily access the epithelia.

Moreover, the strong negative charges will cause mucus/particle interactions. Small neutral particles will likely cross the mucus layer with little hindrance. While negatively charged particles will likely be repelled by the mucus layers own negatively charged residues, and positively charged particles will bind the oppositely charged mucus and become trapped. This will unquestionably affect the absorption characteristics of particles that fall into these categories, 22

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Though many scientists understand the modulatory impacts of mucus on absorption in the small intestine there are several issues. One of the major sources of mucus for in vitro purposes involves the extraction of fresh mucus from the small intestines of pigs. Despite meticulous mucus cleaning processes, cells used in in vitro absorption models show poor survival when coated with a layer of native mucus, severely limiting the efficacy of absorption studies using this method. It is likely that the cell death is caused by toxic impurities and microbes that were not removed by the cleaning process.

Engineered Mucus; the solution The Aelius Biotech Engineered Mucus may be a solution to this problem. The mucus, engineered from porcine small intestinal mucin, has been shown in our experiments to be compatible with cell culture systems in experiments where native mucus would have caused cell death.

My PhD will focus on developing and validating this engineered mucus. Using a library of pharmaceutical compounds and high-performance liquid chromatography (HPLC), I will analyse the permeation of each pharmaceutical through varying thickness of native mucus using a transwell model. These native mucus permeations will act as a guideline to achieving physiologically relevant engineered mucus.

Using the same library, I will analyse the permeation of each pharmaceutical through varying thickness and concentrations of engineered mucus. Following the collection

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The drug permeation transwell model in action: these chambers are lined with mucus, representing the small intestine where food is being digested of data sets for both types of mucus, the different types will be correlated against one another to identify a concentration and thickness of engineered mucus that yields the most similar permeation results to native mucus. Any suitable variables will be assessed to make sure it allows cell survival, before carrying out absorption studies using a cellular absorption model with an incorporated engineered mucus layer. Data will then be validated against data for the drugs seen in vivo. blogs.ncl.ac.uk/react

As previously mentioned, the cell/mucus absorption model can be integrated into the Aelius Biotech model gut system to provide a complete and accurate modelling of digestion and absorption in the digestive tract. Ultimately, using this world leading model, Aelius Biotech can work with companies to create novel solutions gastrointestinal disease and conditions, develop and improve drug delivery models, and in the process reduce the use of and reliance on animal models.

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Developing Seaweed Biomass as a Biofuel Feedstock Alex Goodridge - Durham University As we attempt to transition to a more sustainable society and reduce our dependence on fossil fuels, we not only need to invest in new renewable technologies but also increase the efficiency of existing technologies. For example, we use biomass from energy crops such as land plants and algae to manufacture biofuels. Plant and algal biomass is carbohydrate-rich, making it ideal for bioethanol production (by fermentation) and also biogas production (produced by digesting biomass with certain microorganisms). Some algae also have an extremely high lipid content – which can be extracted and processed into biodiesel.

One way to improve the efficiency of biofuel production is by improving the quality of biomass we use to generate it.

With plant biotech – the use of molecular biology to research and genetically enhance plants, we can develop better energy crops.

The impact of environmental stress on energy crop cultivation Plants must withstand periodic changes in temperature, water availability, and sunlight. Extreme conditions such as drought and freezing kills crops, meaning stress tolerance is essential.

Plant biologists investigate the genetic basis of plant stress tolerance, so more hardy 24

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crops can be engineered. Using model organisms such as thale cress and freshwater algae, scientists over time have built a model of the plant cellular stress response. Simply put, stress (for example, heat) causes protein misfolding, loss of enzyme function, and disrupted metabolism. Disruption of metabolic processes (e.g. photosynthesis) generates reactive oxygen species that cause further damage to cell structures and macromolecules.

The cell must protect and repair itself to restore homeostasis. The typical stress response involves upregulation of proteins like chaperones (that help stabilise and fold other proteins during stress), DNA repair enzymes, and enzymes involved in antioxidant biosynthesis. The complexity of stress responses varies between organisms.

Many evolutionary biologists consider that the evolution of a complex stress response was a key factor in the eventual colonisation of land by the aquatic ancestor of plants.

We can exploit plant and algal stress responses for our own benefit. Lipids, antioxidants and pigments accumulate during stress, which are extracted for fuel, commercial and therapeutic purposes.

Exposure to prolonged and severe stress

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Ulva, a green seaweed found in tide pools worldwide disrupts normal cell function, as stress responses are energetically taxing. This leads to irreversible cell damage and death.

Over human history through domestication we have developed stress-tolerant crops.

However, with climate change – where more frequent extreme environmental events expected, and with increased demands for food and fuel worldwide, we need better crops. More stress-tolerant crops are essential for more unpredictable climates.

One solution is to use genetic engineering for crop enhancement. blogs.ncl.ac.uk/react

How can we design better energy crops?

In plant biotech, there are a range of techniques scientists use to identify and characterise genes involved in stress tolerance.

Genetic studies can be used to identify genes that are turned on and off in different stress conditions. This helps researchers identify different genes that are involved (and also not involved) in responses to different kinds of stress.

Once candidate genes are characterised, scientists use gene Credit: Boston University

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RESEARCH editing technologies to knockout or enhance the function of specific genes. Scientists can also clone genes from one organism and express them in another. Using these techniques (in addition to many others) scientists can piece together the function of genes involved in stress tolerance, enabling better crop design.

Intertidal seaweeds are an ideal biomass feedstock Use of land crops for biomass is controversial. Growing energy crops may mean repurposing land dedicated for food production. Whilst the actual economic impact of the 'food vs fuel' argument is debated, sourcing alternative biofuels is still important. Algae and seaweeds (known as ‘third-generation’ biofuels) can be grown in tanks or offshore, avoiding land-use debates. Seaweeds grow fast and have a particularly carbohydrate-rich biomass perfect for fermentation into bioethanol.

Figure 1. Third generation biofuels are derived from microalgae and macroalgae (which includes seaweeds) Intertidal seaweeds are particularly interesting as they are subject to frequently changing conditions at the coast caused by rising and falling tides. Seaweeds must survive repeated dehydration and rehydration, and also withstand extremes of temperature, wind, salinity, and sunlight at low tide. Until recently there have been few research tools available for seaweed biotech.

Therefore, scientists currently have a poor understanding of seaweed stress responses compared to plants - which limits our ability to exploit it as a crop. This is something I focus on as part of my PhD research.

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How do seaweeds switch on stress responses?

My lab group at Durham University investigates how we can more efficiently process the green sea lettuce Ulva into biofuel. Part of that work involves characterising how Ulva responds to different growth conditions and understanding how it tolerates stress.

In 2018, the full Ulva genome was published. The availability of a genome was a significant advancement for seaweed biotech, making it easier for researchers to identify and characterise genes involved in different processes.

In my research, I am interested in how different parts of the seaweed cell respond to stress. For example, by assessing stress responses in the chloroplast and the mitochondria – the site of photosynthesis and respiration, we can determine how seaweeds protect the metabolic machinery.

At low tide, seaweeds are exposed to multiple kinds of stress at once. My research also considers how different kinds and combinations of stress impacts responses. For example, does heat stress elicit one kind of response and light stress another? Does a combination of these stresses have another effect altogether?

In the first instance, this can be investigated by monitoring how stress markers such as reactive oxygen species and stress proteins, such as chaperones, respond to different conditions. Using bioinformatics tools, I have identified genes for heat shock proteins (or HSP) in Ulva that are targeted to different locations of the cell. HSPs are a family of stress-responsive chaperone proteins that in plants and algae can be

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Javed et. al : Types and generation of biofuels

Biofuels are diverse, and have been generated from many sources targeted specifically to the mitochondria, chloroplast, cytoplasm, nucleus, or endoplasmic reticulum. We also aim to tag these proteins with a fluorescent probe (for example the jellyfish green fluorescent protein), so we can image the protein’s actual location in the cell.

By performing gene expression studies with seaweed cultured under different conditions, my initial findings indicate that the intensity of the HSP heat response is greater when seaweed is cultivated in the light, rather than the dark. Mimicking low tide by removing seaweed from seawater also increased the HSP heat response compared to submerged seaweed. As the response to multiple stressors is greater than the response to heat stress alone, it appears that seaweed HSPs might respond to different kinds of signals. With the stress response being a significant energetic strain on a cell, it is important that the intensity of a response matches the severity of the stress blogs.ncl.ac.uk/react

the organism is exposed to, so as to not waste energy and resources. My findings suggest that this is the case in Ulva, as a more intense stress response is seen when the seaweed is more severely challenged.

Interestingly, none of HSPs responded to light stress or removal from water on its own. Early evidence also indicates that the mitochondrial and chloroplast targeted HSPs respond differently to those in the cytoplasm, as neither appeared to respond to any combination of stress I tested.

Further work is definitely needed to verify this; however, this early data provides some clues at how seaweeds tolerate high stress at low tide. A greater understanding of seaweed cell biology will help us develop it as a better crop, furthering our ability to use it as a sustainable biofuel feedstock which will hopefully increase the economic viability of producing algaederived biofuels, and further reduce dependency on unsustainable fuels.

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Alginate in Corneal Tissue Engineering Anastasia Kostenko - Newcastle University The cornea is a dome shaped transparent clear outer layer at the front of the eye. Although it is a fairly simple tissue, it is very important. The cornea acts like the window of the eye – it controls the entry of light into the eye and is responsible for 65-75% of the eye's total focusing power. Moreover, the cornea acts as a structural barrier to protect the eye against foreign bodies.

The cornea has great self-healing potential and can regenerate from minor scratches and abrasions. Unfortunately, if the damage inflicted is too great, for example in chemical burn victims, the cornea can no longer regenerate and can become opaque, leading to loss of function. This can result in partial or complete blindness. Additionally, pathological conditions such as Stephen–Johnson syndrome, keratoconus, and Fuch’s dystrophy also affect the cornea and can lead to blindness.

According to World Health Organization 10 million people currently require a corneal transplant worldwide. The most routine treatment is a corneal allograft - tissue that is transplanted from one person to another.

However, currently there is a shortage of good-quality donor tissue suitable for transplantation. For patients with autoimmune conditions, chemical burns, and infections transplantation is not possible.

Moreover, the growing use of corrective eye surgery leaves the corneas unsuitable for allografting, which further increases the 28

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gap between the demand of donor tissue and the supply available. Therefore, artificial alternatives to donor corneal tissue are of great interest.

The field of tissue engineering aims to recapitulate native tissue morphology, compensating for the loss or failure of tissues or organs by developing functioning alternatives. Professor David Williams, one of the leading experts in the field of tissue engineering described it as “the persuasion of the body to heal itself, through the delivery to the appropriate sites of molecular signals, cells and supporting structures”. Corneal tissue engineering is a strategy to develop corneal tissue substitutes. It is paramount to take the design, the mechanical properties. and the transparency of the supporting structure into account, mimicking the natural cornea.

Recently, the technique of threedimensional (3D) bioprinting has been developed in the field of tissue engineering.

The principle of 3D bioprinting integrates biomaterials, live cells and controlled motor systems for creating complex structures.

This particular layering of biocompatible support structures, factors and cells aims to recapitulate native biological tissue and has tremendous potential in addressing the lack of suitable alternatives to corneal transplants. One of the most important components of 3D bioprinting is the bioink. Bioink is a mixture of cells, biomaterials and bioacblogs.ncl.ac.uk/react

tive molecules that create the printed construct. Favoured biomaterials for bioink development are hydrogels - materials that can absorb and retain large quantities of water. This water-retaining property is important, as it simulates the natural environment in the body. Other advantageous characteristics of hydrogels are that they are non -toxic and do not elicit an immune response in the host’s body and can support cell survival. The hydrogel I am using in my project is alginate – a natural polysaccharide derived from brown algae. Alginate is water soluble and is possible to rapidly gel by crosslinking with divalent cations such as: calcium, strontium and barium ions. Crosslinking can occur by directly depositing the alginate into a pool of the crosslinking solution or by spraying over the extruded cellladen hydrogel. Alginate is a highly extrudable material and has good biocompatibility with cells. Alginate is also bioinert, which means it lacks bioactive motifs to interact with cells directly, however its molecular structure permits funtionalization with bioactive motifs. Additionally, alginate is wellsuited for the most commonly employed extrusion-based method of 3D bioprinting, thus making it a good candidate for a bioink for corneal bioprinting.

the crosslinking bath for the purpose of improving cell-alginate interaction and subsequent cell survival. I have been investigating the extrudability and geometric properties of the produced fibres and observed inversely proportional relationship between length and diameter of produced fibres; fibre length decreased whilst fibre diameter increased in response to the presence of gelatin in the crosslinking bath in a concentration-dependent manner. Encapsulated human limbal stromal fibroblast, the native cells of the cornea, remained viable over 7 days in culture.

To summarise, my research suggests that the nature of the crosslinking bath that the bioink is extruded into can have a considerable effect on the properties of the fibres.

Through incorporating gelatin into the crosslinking bath, gelation kinetics can be modified. For future corneal bioprinting applications, the properties of the crosslinking solution should be considered critical to control the printed fibre diameter. Solving these problems will allow us to tackle this serious issue of lack of availability of corneal transplants.

My aim is to characterise alginate based bioinks and crosslinking gelation baths in terms of physiochemical and biological properties for 3D bioprinting, thus improving the future 3D bioprinting outcomes of the corneal substitute. The hypothesis is that specific formulations of alginate are able to both retain and direct cell function and can act as bioinks for subsequent 3D bioprinting. So far, I have attempted to functionalise alginate fibres via the addition of gelatin in blogs.ncl.ac.uk/react

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