The Action Mechanism Of CD4~+T Lymphocyte Subgroup Th9in Children With Immune Thrombocytopenia

ObjectiveExplore the expression change and possible mechanisms of Th9lymphocytesand cytokine interleukin-9in children with immune thrombocytopenia (ITP).MethodWe studied36cases of newly diagnosed ITP in children as ITP group which hadbeen admitted to The First Affiliated Hospital of Zhengzhou University during March2013to January2014.At the same time,20healthy children were selected fromwhom have came The First Affiliated Hospital of Zhengzhou University for healthexamination and were studied as control group. The selection was conductedaccording to the principle of random and group matching in which the age and genderwere matching factors. Children in ITP group were diagnosed under the2011American society of hematology (ASH) diagnostic criteria and with no severehemorrhage upon their admission. All children had no other autoimmune、infectiousor blood/neoplastic diseases, and hadn’t been treated with corticosteroids,immunoglobulin or other immunomodulators within one month. The research wasconducted under the permission of the Ethics Committee of The Affiliated Hospital ofZhengzhou University and their next of kin’s informed consent.Collect early morning fasting heparin anticoagulant blood2ml,800μl of which were to measure the portion of Th9cells by flow cytometry,200μl were to measurethe expressional level of PU.1mRNA by real-time quantitative PCR(RT-PCR); therest of it were centrifuged to get plasma and conserved in-20℃,then measure thelevel of IL-9by enzyme linked immunosorbent assay(ELISA).The experimental datawas analyzed by SPSS17.0statistical software. Shapiro-Wilk test and Levene testwere used to proceed normality test and homogenetity of variance test.Measurementdata were described by means±standard deviation(X S) or median (interquartilerang) according to their distribution type. Use T test and Wilcoxon rank sum forComparison between groups of quantitative data, chi-square test for qualitative data.Conduct pairwise correlation test between the values of PU.1mRNA, Th9and IL-9and PLT. Perform Pearson product moment correlation or Spearman rank correlationaccording to whether data meets the bivariate normal and linear conditions or not.Take=0.05as significance level.Results1. The expressional levels of PU.1mRNA (Ζ=1.864, P=0.062), and the ratio ofTh9cell (t=1.824, P=0.074) in ITP group were higher compared with normal controlgroup, but the difference has no statistically significance; Levels of IL-9in ITPgroup were significantly higher than the normal control group (t=3.014, P=0.004),the difference has statistically significance.2. Correlation analysis: The expressional level of PU.1mRNA was positivelycorrelated (rs=0.436, P=0.008) to the radio of Th9cells, the correlation hasstatistically significance; the expressional levels of PU.1mRNA were positivelycorrelated (rs=0.254, P=0.135) to IL–9levels; the radio of Th9cells was positivelycorrelated with IL-9levels (r=0.034, P=0.84),the correlation has no statisticallysignificance; the expressional levels PU.1mRNA were negatively correlated with PLTaccounts (rs=-0.045, P=0.793);the ratio of Th9cell and PLT accounts werenegatively correlated (rs=-0.048, P=0.780),the correlation has no statisticallysignificance;IL-9levels negatively correlated with PLT accounts(rs=-0.349,P=0.037), the correlation has statistically significance. ConclusionCytokine IL-9maybe promoting T、B lymphocyte and mast cell proliferationand activation involved in the pathogenesis of ITP in children;but the role of Th9cells in its pathogenesis is not clear yet.