Nature: Transforming skin cells into photosensitive cells Blind mice see the light again!

Many retinal diseases eventually lead to blindnessFor example, age-related macular degeneration, the leading cause of blindness in people over 65 years of age, has more than 170 million patients worldwide;the cause of the eventual blindness of these eye diseases is the loss of photosensitive cells in the retinaBecause it is difficult to regenerate, the process of blindness cannot be reversed once the photosensitive cells are lostThere are currently no effective treatments to help patients restore vision, except to prevent and delay as much as possibleTherefore, the search for a way to regenerate photosensitive cells has become a key direction for researchersover the past decade, scientists have used induced pluripotent stem cells (iPS) techniques to achieve this goalThis technique can grow skin cells or blood cells into stem cells, which then shape the direction of the stem cell's development and produce photosensitive cellsIn this study, however, ophthalmologists have found new ways to skip stem cellsafter repeated groping, the researchers determined a "cocktail" formula consisting of five small molecular compounds that activate or suppress different developmental signals within the cellThese compounds are "fed" to cultured skin fibroblasts in different combinations at certain times, eventually changing the fate of these skin cellsexamined the gene expression spectrum of new cells, and the researchers found that they were very similar to the genes expressed by the rod cells, a major photosensitive cellAs a result, these new cells are named "chemically induced photoreceptor cells", or CiPCsCompared to the months that used to be reprogrammed with iPS cells, the technique took just 10 days to transform the cellsat different points in cultured cells, adding small molecular compounds that regulate different developmental signals, in just 10 days, can transform human skin fibroblasts into CiPCs (Photo: Source: Supplied)but CiPCs express genes similar to viewrodr cells, which does not mean that they can replace the work of the rod cellsThe researchers then carried out transplant experiments, implanting CiPCs into the eyes of retinal lynostic mice to test the cell's function before transplanting cells, these mice did not feel the light because of the lack of rod cells, and the eyes did not show pupil reflection (when the light is strong, the pupil is large when the light is weak) After 3 to 4 weeks of cell transplantation, the mice began to see a welcome change: of the 14 mice, 6 had significant changes in the pupil in low-light conditions And the weak light is very sensitive, it is the functional characteristics of the rod cells the researchers also conducted a "light-weartest test" to assess whether the visual function of the six mice was actually restored Under normal circumstances, mice prefer to hide in the dark But mice that lost sight did not show a preference for dark environments because they did not perceive the strength of light The six mice transplanted by CiPCs, who spent as much time in dark conditions as normal-sighted mice, significantly longer than blind mice without cell transplants Mice successfully transplanted with CiPCs preferred to stay in dark environments as normal-sighted mice (Photo: Source: 1) over time, waiting until 3 months after transplantation to continue to examine these once-blind mice, the researchers observed that many CiPCs were still alive and that they were connected to other nerve cells in the retina and were truly part of the retina Dr Anand Swaroop, one of the study authors, concluded: "This is the first time that studies have shown that reprogramming directly with chemical reprogramming can produce retinal-like cells, which gives us a new and faster strategy to develop therapies for retinal diseases such as age-related macular degeneration." Three months after the transplant, the still-surviving CiPCs (green) were integrated into the retinas of mice (Photo: Source: 1) of course, there is still a long way to go before this technology to regenerate photosensitive cells can be applied to human patients The researchers say subsequent optimizations will also allow for a higher number of functional transplanted photosensitive cells, further improving efficiency by directly modifying cells Researchers have planned to conduct a clinical trial to test whether the treatment is suitable for eye diseases such as retinal pigmentation, according to the U.S National Eye Institute, which funded the project we look forward to innovative technologies to bring real light to our patients! Reference s Biraj Mahato et al., (2020) Pharmacologic fibroblast reprogramming into photofits restores vision Nature DOI: https://doi.org/10.1038/s41586-020-2201-4 into s Retrieved Apr 15, 2020, from https:// original title: Today's Nature: Blind Mice See Light Again! New technology to transform skin cells into photosensitive cells is on!