Retinitis pigmentosa (RP) is defined as a group of hereditary retinal degenerative diseases which cause progressive vision failure and blindness. This condition however impacts the photoreceptor cells in the retina and it degenerates with time. Because RP is the primary cause of inherited blindness, it is not easy to manage. Stem cell therapy is steadily gaining ground in Canada, and this invention is being seen as a hope for victims of these conditions.
Understanding Retinitis Pigmentosa
Retinitis pigmentosa is a generic term given to a family of diseases resulting in the degeneration of the retina. This condition is characterized by gradual degeneration of the rod cells which are needed for vision in low light and peripheral vision; the cone cells which are needed for central vision and colour vision follow suit. The symptoms often start during childhood or early adulthood and can entail night blindness, tunnel vision and consequently total blindness.
It is mainly a result of defects involving the genes leading to the malfunction and hence the death of the retinal cells. The progressive nature of RP means that modern treatment largely consists of symptom control without being capable of stopping or reversing the degeneration process.
Stem Cell Therapy
Stem cell therapy offers significant advancements in the treatment of RP. Retinal cells have also been derived from stem cells because of their superior characteristic of differentiating into a variety of cell types. The ability to repair the damaged tissue makes stem cell therapy one of the viable ways of managing RP.
Stem cell types that are used in the RP Treatment
Embryonic Stem Cells (ESCs): These are cells isolated from the earliest developmental stages of multicellular organisms. Like all stem cells, ESCs are pluripotent and therefore are capable of differentiating into retinal cells.
Adult Stem Cells: The retinal progenitor cells are multipotent precursors of retinal neurons and glia or the mesenchymal stem cells. RPCs are obtained from the retina and hold the capability to replace dead or damaged retinal cells. MSCs are usually derived from bone marrow or adipose tissue exerting effects on inflammation processes and promoting the survival of retinal cells.
Induced Pluripotent Stem Cells (iPSCs): These are created through the process where scientists return adult somatic cells to an embryonic-like state. Further, iPSCs seem to be individualized as they can be generated from the patient’s cells and, hence are much less likely to experience immune rejection.
Mechanism of stem cell therapy
Stem cell therapies for RP operate through several mechanisms:
Cell Replacement: Stem cell therapy envisions replacing the lost or nonfunctional photoreceptors by transferring the healthy ones derived from the patient’s mouth into the damaged retina.
Neuroprotection: Neurotrophic factors such as GDNF can be secreted by stem cells and subsequently reduce the degeneration of the existing retinal cells, thus, halting the disease progression.
Tissue Regeneration: Stem cells can be used to replace the components of the retinal microenvironment that affect the survival and function of the cells that are being transplanted.
Conclusion
The available stem cell therapies are highly sophisticated. Stem cells contain the potency to regenerate. We believe these treatments at StemCellCure, and our work on retinal degenerative diseases will bring a better and brighter future to the patients.