动物造模,药效评价,白癜风 z-bio 2024-06-19 668

　　Humans can induce local depigmentation in some animals, such as chickens, rodents, dogs, cats, and horses. These animals often have anti melanocyte antibodies in their bodies, with the most commonly used being Smyth line (SL) chickens and C57BL mice.

　　【 Modeling Mechanism 】 SL chicken was first discovered by chance as a white hen in a brown line cage. From the markings on its wings, it appears brown when hatched. After repeated genetic selection experiments, Smyth found that SL chickens and their parents have different MHC antigens, and their three sublines (SL101, SL102, SL103) each have one genotype of their parent MHC.

　　The C57BL mouse is an inbred strain of mice cultivated by Little in 1921, which is the offspring of female mouse 57 and male mouse 52 mating. Those with black fur in C57 are called C57BL, and there are subgroups such as C57BL/6, C57BL/6J, and C57BL/10. Among them, C57BL/6J Ler vit/vit mice are homologous mutant lines of C57BL/6J, which are mouse models of vitiligo.

　　The occurrence of SL chicken vitiligo is based on the inherent defects of melanocytes and the autoimmune basis targeting melanocytes. The interaction of these two factors ultimately leads to the loss of melanocytes. SL chickens show depigmentation of their feathers at 6 to 20 weeks, with a 70% to 90% chance of developing vitiligo. Under the microscope, depigmented feathers show a lack of melanin. When pigment loss occurs, it can be accompanied by varying degrees of alopecia areata or baldness like appearance changes, similar to human alopecia areata. Observations have shown that lymphocyte infiltration and cytokine expression levels increase in the affected area of SL chickens. When melanocytes are completely lost, their expression returns to its initial level. In addition, in the weeks leading up to depigmentation, anti melanocyte antibodies can be detected in the serum, which may disrupt melanocytes through complement mediated pathways and antibody dependent cytotoxicity.

　　Adult C57BL mouse trunk melanocytes are limited to the hair follicles, and their hair follicle melanocytes only synthesize melanin. C57BL/6J Ler vit/vit mice can spontaneously exhibit depigmented spots on the back and abdomen, and their hair gradually turns white. Similar to SL chickens and human vitiligo patients, mice also exhibit depigmentation around the eyes.

　　【 Model Evaluation and Application 】 The pathogenesis of SL chickens is similar to that of humans in genetics, immunity, and other aspects, making them a good animal model for studying human vitiligo. Widely used in the study of the pathogenesis of vitiligo. However, this animal model does not involve depigmentation of the epidermis and cannot be used for research on skin vitiligo.

　　Similar to SL chickens, C57BL mice are suitable for studying the formation of mouse hair pigments and the interactions between cells (keratinocytes, melanocytes, and fibroblasts) during hair growth. The research related to vitiligo mainly includes the regulation of hair follicle melanocyte proliferation and differentiation, the study of vitiligo pigmentation, and the inheritance of vitiligo in mice.