Recognised expert in aquaporins in Sjögren’s syndrome

Laboratory of Pathophysiological and Nutritional Biochemistry – LBPN Recognised expert in aquaporins in Sjögren’s syndrome

The Laboratory of Pathophysiological and Nutritional Biochemistry (LBPN) is one of the few laboratories in Belgium to specialise in the study of aquaporins (water channels) in salivary glands, in a physiological and pathophysiological context. The laboratory, which has some fifteen members, is recognised worldwide for its expertise in aquaporins active in Sjögren’s syndrome, an autoimmune disease characterised by dry eyes and dry mouth and affecting nearly 0.6% of the population with a ratio of 9 females to one male.

Benefiting from funding by the FNRS, the European Commission and private funds, LBPN conducts 3 to 4 joint projects per year. Its researchers focus on the expression and role of aquaporins in salivary glands in physiological and pathophysiological conditions. This fundamental research work is complemented by translational research projects in collaboration with physicians at the Erasme hospital. The objective is to understand the molecular mechanisms of aquaporin-5 involved in saliva formation. In addition, LBPN is studying the role of other aquaporins involved in other pathological contexts such as adipocyte, obesity and various gastrointestinal diseases.

Today, the researchers of LBPN are working with Prof. M. Soyfoo of the Erasme Hospital Rheumatology Department on the HarmonicSS project. Selected under the European Horizon 2020 framework programme, this project brings together 36 partners from 13 countries, including 30 academic and 4 industrial partners and 2 patients’ associations. The objective is to harmonise the integrated analysis of data from Sjögren patients by collecting the clinical data of several thousand patients. This collection should lead to a better understanding of the characteristics of patients, the elaboration of sub-classes and the analysis of patients concerning a number of different aspects.

In parallel, the LBPN participates in a research project supported by the FNRS and the Research Funds of Québec. This is a collaboration between the ULB and McGill University based on an inter- and multidisciplinary approach involving technology transfer. Here the objective is to optimise and validate a 3D bioprinted salivary gland model to analyse the cell biology of aquaporin-5 with a view to better understand its function in a physiopathological context. This project is of interest regarding the screening of medicines and the development of personalised medicines: mini-gland transplantation in patients is the long term objective.

LPBN’s expertise is all the more crucial because today no treatment is available for Sjögren’s syndrome: beyond the existing palliative solutions, the challenge is to develop a customised medicine based on the new treatments, enabled by a better understanding of the molecular mechanisms involved in the physiology of the salivary gland and the pathophysiology of the disease.

In addition, LBPN is seeking suitable funding to enable it to continue its work. The new technologies (biochemical, pharmacological, advanced molecular and cellular biology methods) are very expensive but also indispensable for the progress of cutting-edge research. This is also why the research partnership with McGill University is so important: ULB hopes to benefit from the transfer of 3D bioprinting technology. The hope is that, in the not too distant future, it will be possible to provide effective therapeutic solutions to patients in need with dysfunctioning salivary glands due to Sjögren’s syndrome or radiotherapy for cancer of the head or neck.

Salivary secretion implies molecular mechanisms involving a flow of transcellular water from the secretory acinar cells to the glandular lumen. This water flow is made possible by aquaporin-5 (AQP5), a protein belonging to the family of transmembrane proteins called aquaporins, also known as water channels. The intracellular transport of aquaporin-5 enables the latter to locate itself in the cell membrane, thereby allowing the water to pass. LPBN is looking to understand the cellular biology of AQP5 involved in saliva formation.

Laboratoire de Biochimie Physiopathologique et Nutritionnelle LBPN Campus Erasme CP611 - Route de Lennik, 808 - B-1070 Brussels Tel.: +32 (0)2 555 62 10 E-mail: cdelport@ulb.ac.be http://cvchercheurs.ulb.ac.be/Siteprev/unite/ULB762.php