Could Stem Cells be the Next Breakthrough in Medicine? Iris Cheung (Year 12, Gellhorn)
1 INTRODUCTION Stem cell* therapy has become increasingly advanced and reliable in the fields of scientific research and regenerative medicine in recent years. Growing at a rate of 36% per year the market will expand even more rapidly when a breakthrough treatment for non-communicable diseases or lifestyle factors occurs [1]. Through promoting the repair of dysfunctional, injured or diseased cells and cell rejuvenation, could this cutting-edge therapy serve to be a turning point and game changer in modern medicine, providing hope for untreatable diseases and creating other breakthroughs? 2 WHAT ARE STEM CELLS? As the name may suggest stem cells are “stems” / sources from which new, different cells can be made. They are undifferentiated cells which can keep dividing to give rise to other cell types in a process known as “specialization”. This is what allows it to be useful in regenerative medicine. There are four types of stem cells: totipotent, pluripotent, multipotent and unipotent stem cells. Sources of stem cells include embryonic stem cells, adult stem cells and umbilical cord stem cells. All humans start out as one cell - a zygote (or a fertilized egg cell). The zygote divides by mitosis to form a blastocyst. Eventually, the cells begin to differentiate, taking on one particular function in a part of the body (differentiation). With the correct stimulus given to the unspecialized cells, some genes can be switched on and become active. Messenger RNA (mRNA) is then made from those active genes only and moves out to the ribosomes where it is read. Appropriate proteins are then made, performing a specific function [2]. Embryonic stem cells are derived from blastocysts which is a stage of pre-implantation embryos that have an inner cell mass. After that, these cells are placed in a culture dish filled with culture medium. These cells are pluripotent because in the end, they are able to differentiate into every cell type in the organism. However, one of the problems with embryonic stem cells is the ethical restrictions related to their use in medical therapies [3]. Somatic or adult stem cells are undifferentiated cells that are found among differentiated cells in the whole body after development. These stem cells enable the healing, growth, and replacement of cells that are lost each day; however they have a restricted range of differentiation options. Among the many, there are the following types:
*Definitions of key words in bold can be found in the glossary at the end of this article
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