白细胞相关免疫球蛋白样受体-1在免疫性血小板减少症患儿中的表达

Expression of leukocyte-associated Ig-like receptor-1 in children with immune thrombocytopenia

摘要:

目的 观察白细胞相关免疫球蛋白样受体-1（LAIR-1）在免疫性血小板减少症（ITP）患儿中的表达变化，探讨其在ITP发病中可能的机制。方法 采用流式细胞术检测40例ITP患儿外周血CD4⁺ T细胞、CD8⁺ T细胞及CD19⁺CD20⁺ B细胞膜LAIR-1的表达率；ELISA检测ITP患儿血清中可溶性LAIR-1（sLAIR-1）含量及实时荧光定量PCR法检测ITP患儿LAIR-1 mRNA表达水平。32名同龄健康儿童作为对照组。结果 ITP组CD19⁺CD20⁺ B细胞比例高于对照组（P<0.05），而CD4⁺ T细胞比例低于对照组（P<0.05）。ITP组CD4⁺ T细胞、CD8⁺ T细胞膜LAIR-1的表达低于对照组（P<0.05）。ITP组血清sLAIR-1含量和LAIR-1 mRNA 表达高于对照组（P<0.05）。结论 ITP患儿中CD4⁺ T细胞、CD8⁺ T细胞膜上LAIR-1表达降低，血清sLAIR-1表达增高，提示LAIR-1可能是导致ITP患儿免疫失衡的重要因素。

Abstract:

Objective To study the expression of leukocyte-associated Ig-like receptor-1(LAIR-1) in children with immune thrombocytopenia (ITP), in order to explore the possible role of LAIR-1 in the pathogenesis of childhood ITP. Methods Expression levels of LAIR-1 on CD4⁺ T cells, CD8⁺ T cells and CD19⁺CD20⁺ B cells of peripheral blood were measured in 40 children with ITP by flow cytometry. Serum level of solubility LAIR-1 (sLAIR-1) was measured using ELISA. Real-time PCR was used to measure LAIR-1 mRNA expression. Thirty-two healthy children served as the control group. Results The percentages of CD19⁺CD20⁺ B cells in the ITP group were significantly higher than in the control group (P<0.05). In contrast, the percentage of CD4⁺ T cells in the ITP group was significantly lower than in the control group (P<0.05). The expression levels of LAIR-1 on CD4⁺ T cells and CD8⁺ T cells were significantly lower in the ITP group than in the control group (P<0.05). Serum sLAIR-1 level and LAIR-1 mRNA expression in the ITP group significantly increased compared with the control group (P<0.05). Conclusions LAIR-1 expression on CD4⁺ and CD8⁺ T cells decreases and serum sLAIR-1 level increases in children with ITP, suggesting that LAIR-1 may play an important role in immune imbalance in these children.