Semantron 22 Summer 2022

Stem cell therapies

surgeries as it eliminates the risk of immunological rejection. In the UK, 6,000 people are estimated to be on the NHS transplant list, with a 3-5 year waiting period. With transplants, however, there are extensive recovery periods and a life-long programme of anti-rejection medication, which does not eradicate the risk of rejection (NationalKidneyFoundation, 2020). In fact, this course of immunosuppressants increases the likelihood of cancer diagnosis by 2-3 times (Whitty, 2019). By contrast, growing stem cells in cultures takes only 2-12 weeks before producing functional tissues. Consequently, stress on transplant waiting lists would be alleviated, reducing the likelihood of patient complications that require medical intervention. Furthermore, the identical antigenic materials will yield faster recovery times and better overall function whilst avoiding the risk of rejection, factors that enhance patient treatment and quality of care (Brandt, 2020). However, there are some drawbacks to using stem cells. Firstly, clinical uses of stem cells must be regulated extremely carefully. Due to their natural instincts to differentiate, stem cells can easily develop into a multicellular mass called a teratocarcinoma (Yu, 2014). This is a malignant tumour, made up of cancerous cells, that will divide uncontrollably. This issue most commonly arises due to incomplete differentiation. All stem cells must be differentiated into the desired cell type using chemical signalling and growth factors, otherwise individual cells will develop into random cell types, resulting in a bundle of random cells that continues to grow. But strict protocols and regulations have been established to reduce practical errors such as changing the growth medium the cells grow in every 2-3 days (Lian, 2012). Moreover, over 2,000 growth factors have been developed to ensure that the process of inducing differentiation is completed fully. There is also stigma surrounding the use of a form of pluripotent stem cells called embryonic stem cells (Lo, 2009). These are extracted from embryos as their cells are not matured and specialized. But in doing so, the life of an embryo is destroyed. This poses an ethical dilemma as embryonic stem cells have a very high degree of potency and differentiation capabilities, but on the other hand, a life is being destroyed. In response to this, induced pluripotent stem cells were researched. These are derived from adult stem cells, which have relatively low potency. However, by removing the stem cells’ genes and forcing new gene expression using four specific growth factors – Oct4, Sox2, Klf4, c-Myc – adult stem cells could be reprogrammed to express higher potency levels (Rezza, 2017). These reprogrammed stem cells would now be a suitable replacement for embryonic stem cells and any therapies.

Case study 1 – orthopaedics

Orthopaedics is a medical speciality that studies injuries and disease associated with the musculoskeletal system. (Throckmorton, 2019). The main aim of this branch is to repair bones and joints that have fractures or degenerated over time. A common structure that requires surgical intervention is the proximal femur, often known as the hip joint. With age, the musculoskeletal system deteriorates, becoming weaker and more vulnerable to breaks. In the UK, over 20% of the population are aged 65 or older. This cohort of the population have the highest rate of incidence of proximal femoral fracture and between 2008 and 2009, more than 68,000 patients sustained a fracture of their hip bone (Wiles, 2011) . According to the UK’s transition demographic model, there is an ageing population, which will result in a greater demand in hip repair therapies.

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