Expression of leukocyte-associated immunoglobulin-like receptor on Treg cells in children with immune thrombocytopenia / 中华实用儿科临床杂志

ABSTRACT

Objective To observe the expression of leukocyte-associated immunoglobulin(Ig)-like receptor-1 (LAIR-1) on Treg cells in children with immune thrombocytopenia (ITP) and the level of soluble LAIR-1 (sLAIR-1),LAIR-2 in peripheral blood,and to discuss the possible role of LAIR in the pathogenesis of childhood ITP.Methods The levels of LAIR-1 on Treg cells of peripheral blood were measured in 36 children with ITP by using flow cytometry.Plasma levels of sLAIR-1 and LAIR-2 were measured by adopting enzyme-linked immunosorbent assay(ELISA).Real-time PCR was used to measure both LAIR-1 mRNA and LAIR-2 mRNA.Twenty-eight healthy children served as the healthy control group.Results The expression of Treg cells in children with ITP was significantly lower than that in the healthy control group [(2.05 ± 0.85) ％ vs (3.04 ± 1.03) ％,t =4.198,P ＜ 0.001].The expression rate of LAIR-1 on Treg cells and tyrosine phosphatase-2 (SHP-2) in children with ITP group had no statistically significant difference with the healthy control group [(71.18 ± 13.36) ％ vs (67.69 ± 13.07)％,t=1.045,P＞0.05;(1.20 ± 0.97) ％ vs (0.85 ±0.66)％;t=1.718,P＞0.05].The levels of sLAIR-1 and LAIR-2 in plasma in children with ITP group were increased significantly than those in the healthy control group [(20.53 ±4.32) μg/L vs (17.51 ± 5.15) μg/L,t =2.424,P ＜0.05;(5.83 ± 1.08) μg/L vs (5.19 ± 1.24) μg/L,t =2.267,P ＜ 0.05].The LAIR-1 mRNA expression level in children with ITP group was significantly increased compared with the healthy control group (t =2.851,P ＜ 0.05),but not the LAIR-2 mRNA expression level (t =1.715,P ＞ 0.05).Conclusions The expression of Treg cells in children with ITP is decreased,and it may be associated with the onset of ITP,and it may suggest that LAIR-1 does not play a leading role in Treg cells when ITP occurrs.And the levels of sLAIR-1,LAIR-2 in plasma are both increased,suggesting that LAIR-1,LAIR-2 may be one of the factors of immune disorders in children with ITP.