慢性特发性血小板减少性紫癜患儿蛋白激酶C检测的意义

Significance of Protein Kinase C Activity Detection in Children with Chronic Idiopathic Thrombocytopenic Purpura

目的研究慢性特发性血小板减少性紫癜(CITP)患儿外周血T细胞蛋白激酶C(PKC)的活性变化及其与T细胞活化和血小板减少程度之间的关系。方法无菌采集30例CITP患儿及30例健康对照组外周血各5mL,T细胞分离富集柱法分离纯化T细胞,采用非放射性核素标记法检测T细胞PKC的活性变化,ELISA检测T细胞活化标志可溶性白细胞介素-2受体(sIL-2R)的表达,血细胞计数仪计数血小板的减少程度。结果CITP患儿T细胞PKC的活性[(0.94±0.23)mmol/(min.L)]与健康对照组[(0.50±0.17)mmol/(min.L)]比较显著增强(t=8.42P<0.05);CITP患儿T细胞活化标志sIL-2R的表达[(528±124)×103U/L]与健康对照组[(296±57)×103U/L]比较显著升高(t=9.31P<0.05);CITP患儿T细胞PKC的活性变化与T细胞的活化标志物sIL-2R的表达呈正相关(r=0.8725P<0.05),与血小板计数呈负相关(r=-0.8107P<0.05)。结论CITP患儿外周血T细胞PKC活性增强可能导致T细胞活化,活性T细胞增多可能引起患儿血小板损伤,提示PKC信号传导在CITP的免疫病理机制中发挥重要作用。

Objective To investigate the changes of protein kinase C （PKC） activity in peripheral blood T lymphocytes in children with chronic idiopathic thrombocytopenic purpura （CITP） and the relationship between PKC activity, T lymphocytes activation and thrombocytes decrease. Methods Collecting sterile peripheral blood from CITP children （n = 30） and healthy children （n = 30） ,T lymphocytes were isolated and purified by the T cell segregation enrichment column, the PKC activity was detected by non - radioactive assay. Soluble interleukin - 2 receptor（ sIL - 2R）, which was T cell activated marker, was determined by enzyme - linked immunoabsorbent assay （ ELISA）, platelet was counted by cell counting meter. Results Compared with healthy children, PKC activity was significantly enhanced in CITP children [ （0.94 ± 0.23） mmol/（min· L） vs （0.50±0.17） mmol/（min · L）,t= 8.42 P〈0.05].Expression ofsIL-2Rin serum was significantly improved [ （528 ± 124） × 10^3 U/L vs （296 ± 57） × 10^3 U/L,t -9. 31 P 〈 0.05 ]. Besides, relationship between the changes of PKC activity and slL - 2R was positive correlation （ r = 0. 872 5 P 〈 0.05 ）, however, relationship between PKC activity and platelet count was significantly negative correlation （ r = - 0. 810 7 P 〈 0.05 ）. Conclusions Enhancement of PKC activity in CITP children may relate to T lymphocytes activation and result in reduction of thrombocytes, which indicate that PKC signal transduction may play an important role in the immunopathogenesis of CITP children.