The role of SHPS-1 in dendritic cell-mediated autoimmune diseases

SHPS-1，也被称为SIRPα，是一种跨膜蛋白，主要在树突状细胞（dc）中表达。为了阐明SHPS-1在自身免疫性疾病中的作用，我研究了稳定状态下dc的功能。我发现，在SHPS-1 KO小鼠的脾脏和淋巴结中，CD8^-CD4^+常规dc （CD4^+ cDCs）的数量明显减少。这种减少可能是由于DCs的半衰期缩短。此外，CD47 KO小鼠中CD4^+ DC的数量也减少，这表明非造血细胞上的CD47与DC上的SHPS-1的相互作用对DC稳态的调节很重要。

SHPS-1, also known as SIRPα, is a transmembrane protein, which is predominantly expressed in dendritic cells (DCs). To clarify the role of SHPS-1 in autoimmune diseases, I examined the function of DCs in a steady state. I found that the number of CD8^-CD4^+ conventional DCs (CD4^+ cDCs), is markedly decreased in the spleen and lymph nodes of SHPS-1 KO mice. This reduction is likely attributable to a reduced half-life of DCs. Moreover, the number of CD4^+ DCs is also decreased in CD47 KO mice, suggesting the interaction of CD47 on nonhematopoietic cells with SHPS-1 on DCs is important for regulation of DC homeostasis.