动物造模,药效评价,视网膜 z-bio 2024-09-03 501

　　Knocking out genes related to retinal diseases to obtain animal models with stable clinical phenotypes and clear genetic backgrounds provides an important research tool for studying the functions of related genes and their encoded proteins. The most commonly used animal model for genetically modified retinitis pigmentosa is RPE-65 gene knockout mice.

　　The human RPE-65 gene is located at 1p31 and encodes RPE specific protein, which is related to retinal vitamin A metabolism. Knockout of this gene disrupts the function of mouse RPE cells, leading to excessive accumulation of all trans retinol and deficiency of 11 cis retinol ester, resulting in apoptosis of photoreceptor cells.

　　In 1998, Redmond et al. successfully cultivated an Rpe65 deficient mouse model, which enabled further research on the Rpe65 gene. Rpe65 deficient mice exhibit excessive accumulation of all trans retinol lipids, which weakens the phagocytic function of retinal pigment epithelial cells and leads to disordered arrangement of the outer layer of the optic rod. At 7 weeks, the density of photoreceptor cells in Rpe65-/- mice decreased, and there was no significant difference in the number of cell layers compared to the control group. At 15 weeks, the length of the outer segment of Rpe65-/- mice was significantly shortened, and the structure of the outer segment disc membrane was disordered. Immunoelectron microscopy showed a decrease in opsin on the outer segment disc membrane; The number of outer nuclear layers began to decrease, and by week 28, the number of outer nuclear layers had decreased by about one-third. The ERG examination results showed a severe decrease in rod response and the presence of cone function.

　　[Model source] Jackson Laboratories in the United States can provide Rpe65 deficient mice.

　　The successful establishment of RPE65 gene knockout mice is marked by the disappearance of total RPE65 protein in the eyes of Rpe65-/- mice. This is used for models of autosomal recessive inheritance RP and LCA.