特发性血小板减少性紫癜患儿骨髓单个核细胞CD_(40)/CD_(40)L表达的意义

Expression of CD_(40) and CD_(40)L in Bone Marrow Mononuclear Cells in Children with Idiopathic Thrombocytopenic Purpura

目的测定共刺激分子CD40/CD40L及其mRNA在特发性血小板减少性紫癜(ITP)儿童骨髓单个核细胞中的表达,研究其与血小板抗体产生的关系,探讨其在ITP发病机制中的作用。方法收集34例ITP患儿。其中急性ITP22例,慢性ITP12例,对照组20例。ITP患儿于治疗前收集骨髓标本,密度梯度离心法分离单个核细胞,应用流式细胞术检测其CD40/CD40L表达水平;提取细胞总RNA,采用RT-PCR、琼脂糖凝胶电泳法测定其CD40/CD40L mRNA表达;于收集骨髓前采集其外周血,采用ELISA法检测其血小板相关抗体(PAIgG)。应用SPSS15.0软件进行单因素方差分析和直线回归相关分析。结果与对照组比较,CD40在急性ITP组[(10.361±4.125)%]和慢性ITP组[(14.066±4.655)%]的表达均增高(Pa<0.01),CD40L在2组的表达亦均增高[分别为(5.094±3.154)%、(6.698±3.673)%,Pa<0.05],CD40在慢性ITP组的表达高于急性ITP组(P<0.05);CD40L mRNA在急性ITP组(0.677±0.111)和慢性ITP组(0.699±0.105)表达均增高(Pa<0.05),CD40 mRNA在慢性ITP组(0.868±0.121)表达高于急性ITP组(0.798±0.076)和对照组(Pa<0.05);CD40、CD40L的表达与PAIgG均呈正相关(r=0.741,0.826Pa<0.05)。结论ITP患儿骨髓单个核细胞CD40及CD40L表达增高,CD40和CD40 mRNA在慢性ITP组表达显著高于急性ITP组,表明CD40/CD40L在儿童ITP尤其是慢性ITP发病过程中可能起重要作用。

Objective To determine the expression of CO - stimulatory molecules CD40/CD40L and its mRNA in bone marrow mononuclear cells in children with idiopathic thrombocytopenic purpura （ITP）, and investigate the relationship between CD40/CD40 L and platelet - associated IgG（PAIgG） production, also to explore their possible roles in the disease. Methods Thirty -four ITP children were divided into 2 groups, the acute ITP （alTP） group （ n = 22 ） and the chronic ITP （cITP） group （ n = 12 ）. Control group included 20 children without ITP. The bone marrow prepare in children with ITP before treatment was collected, density gradient centrifugation was used to separate mononuclear cells. Flow cytometry was applied to detect the expression of CD40/CD40 L. Total RNA was got out from mononuclear ceils, use reverse transcription- polymerase chain reaction （RT- PCR） and agarose gel electrophoresis techniques to semiquantitatively analyze CD40/CD40L mR- NA expression in bone marrow mononuclear cells from 34 ITP children and 20 controls. Eripheral blood was collected before collecting bone marrow, PAIgG was detected by enzyme linked immunosorbent assay （ELISA） technique. One - factor analysis of variance and linear regres- sion was used to analyze the results with statistics SPSS 15.0 software. Results Compared with control group, the expression of CD4o were significantly higher in aITP[ （ 10.361 ± 4. 125 ） % ] group and cITP group [ （ 14. 066 ± 4. 655 ） % ] （ Pa 〈 0.01 ） ; the expression of CD40 L were higher in aITP group [ （5. 094 ± 3. 154 ） % ] and cITP group [ （6. 698 ± 3. 673 ） % ] （ Pa 〈 0.05 ） ; the expression of CD40 in clTP were higher than that in aITP group （ P 〈 0.05 ）. Compared with controls, the expression of CD40 L mRNA were higher in aITP （0. 677 ± 0.111 ） group and clTP group （0. 699 ± 0. 105 ） （Pa 〈 0.05 ）. Compared with controls and aITP group（ 0. 798 ± 0. 076 ）, CD40 mRNA expression were also higher in cITP group（0. 868 ± 0. 121 ） （P 〈 0.05）. The expression of CD40 and CD40L had positive correlation with PAIgG （ r = 0. 741,0. 826 Pa 〈 0.05 ）. Conclusions The expression of CD40 and CD40 L in bone marrow mononuclear cells in children with ITP are higher. CD40 and CD40 mRNA expression in cITP group are significantly higher than in aITP group. The abnormal expression of CD40/CD40L may play an important role in the development of ITP especially in cITP group.