مقالات پذیرفته شده در نهمین کنگره بین المللی زیست پزشکی
The Role of Cell Therapy in the Treatment of Retinitis Pigmentosa (RP)
The Role of Cell Therapy in the Treatment of Retinitis Pigmentosa (RP)
Mahsa Farahi Shandiz,1Mobina Farahi Shandiz,2,*
1. Department of Biology, Ale Taha University, Tehran, Iran. 2. Department of Anesthesiology, Iran University of Medical Sciences, Tehran, Iran
Introduction: Retinitis pigmentosa (RP) is a group of inherited retinal dystrophies that involves the destruction of retinal photoreceptor cells, resulting in progressive vision loss. The disease was identified and named in 1857. Statistics show that approximately 1 in 4,000 people worldwide are affected by this disease. The most important manifestation of the disease is the death of rod photoreceptors, followed by cone photoreceptors. For this reason, most people with this disease, along with other visual impairments, lose night vision. Conventional treatments for degenerative eye disorders are primarily aimed at slowing the progression of the disease, but their long-term benefits depend on the repair and regeneration of damaged eye tissue.
Retina, is a transparent, light-sensitive tissue that contains several layers of cells. This tissue originates from the anterior neural tube during early embryogenesis as part of the central nervous system. Retina is composed of the light-transmitting nerve retina as well as the supporting blood-brain barrier. After photons of light are absorbed by photoreceptors, visual information is converted into chemical signals in retina and then transmitted as nerve signals to retinal ganglion cells. Axons form the optic nerve, which transmits this information to the visual centers of the brain, where the image is processed.
Stem cells have not yet committed to a specific cell lineage. They have the ability to divide and can differentiate into different types of mature, functional cells, making them a valuable tool. Stem cell therapy holds promise as a potential treatment for degenerative disorders, such as neurological disorders. Several studies have demonstrated the potential of different cell types to regenerate ocular tissues, including embryonic stem cells (ESC), induced pluripotent stem cells (iPSC), mesenchymal stem cells (MSC), and retinal progenitor cells (RPC). Stem cell-based therapies have been used in clinical trials to treat retinal diseases with promising results, however many challenges remain, such as the production of clinically standardized cells, transplantation, immune rejection, potential carcinogenic risk, and unclear mechanisms. A potentially better approach is the use of extracellular vesicles (EVs), which are secreted from stem cells. Their advantage over stem cells is their low immunogenicity and ease of administration.
Methods: Over the past few decades, technological advances and the understanding of the human genome have led to the development of a set of novel therapeutic candidates for the treatment of RP. These include gene and cell therapy, neuroprotective agents, and electronic retinal implants.
In addition to cell transplantation, recent advances in the development of 3D neural retinas derived from pluripotent stem cells in culture and the fabrication of 3D cellular constructs using robotics and 3D bioprinting have provided new insights into retinal tissue engineering. Various strategies are also being employed to prevent immune rejection, a common complication of cell transplantation.
Results: Considerable efforts have been devoted to investigating promising types of stem cells, such as LSCs and iPSCs, to address a wide range of ocular diseases. These stem cells show potential for use in various clinical settings due to their distinct properties. It is likely that novel stem cell therapies will be introduced into clinical practice in the near future, not only facilitating tissue regeneration but also providing reduced inflammation and neuroprotective effects through the secretion of exosomes, improving patient outcomes.
Exosomes clearly play key roles in the stem cell-based paracrine pathway in the treatment of retinal diseases. Although exosomes therapy can prevent the risk factors associated with the transfer of dividing cells to the eye, the details of the unknown mechanisms still need to be investigated.
Conclusion: Retinal tissue engineering is expected to make a significant contribution to the treatment of human blindness, especially for retinal diseases. Stem cell therapy is anticipated to replace traditional approaches to the treatment of serious ocular injuries and diseases as an innovative solution. This highlights the multi-mechanistic therapeutic potential of stem cell therapy and will mark a new stage in ophthalmology. Stem cells can not only promote tissue regeneration, but also release exosomes to reduce inflammation and provide neuroprotection, making stem cell therapy a promising approach to treat a wide range of ocular disorders through multiple mechanisms.