CD8^+T细胞在CA16感染手足口病中的表达变化及潜在作用

The Potential Function of Varied Expression of CD8^+T Cells Against CA16

目的:对比分析15~24个月及2~5岁CA16感染的普通型与危重症手足口病(hand,foot and mouth disease,HFMD)患者外周血中CD8^+T细胞的表达情况,寻找发现与CA16致病有关的免疫病理因素。方法:收集2014年5-8月间昆明市儿童医院感染科确诊的儿童HFMD病例外周血标本共72例,其中普通型32例,危重症40例,采用流式细胞术对患者外周血CD8^+T淋巴细胞亚群进行检测分析。结果:15~24个月普通型HFMD患者外周血CD8^+T淋巴细胞百分比略高于正常健康儿童参考值,而危重症患者CD8^+T细胞略低于正常参考值。此外,与正常参考值相比,2~5岁普通型及危重症患者外周血中CD8^+T淋巴细胞百分比均减低,其中危重症患者略低于普通型患者。结论:CA16感染后,不同年龄、不同病情的HFMD患者外周血中CD8^+T细胞的表达变化不太明显,说明CA16感染后,患者体内的CD8^+T细胞基本能够发挥正常的抗病毒免疫效应。而在危重症时,两个年龄段患者CD8^+T细胞百分比略低或减低,说明CA16的持续性感染可能对机体CD8^+T细胞的表达产生了影响,使其杀伤病毒效应减低,这可能是CA16感染诱导神经系统并发症发生的免疫病理因素之一。

Objective：To compare and analyze the expression of CD8＋T lymphocytes subset in peripheral blood in different children with hand,foot and mouth disease（HFMD） infected by CA16 between the age groups of 15 to 24 months and 2 to 5 years, which might disclose the immunopathologic factors related to the pathogenicity of CA16. Method： 72 cases with HFMD of peripheral blood samples were collected in the department of infectious disease in Kunming Children＇s Hospital from May to August 2015,which included 32 mild cases and 40 critical cases.The expression of CD8＋T lymphocyte subsets in patients＇ peripheral blood sample were detected by the flow cytometry.Result：The percentage of CD8＋T lymphocyte in mild patients from 15 to 24 months was slightly higher than the reference value of CD8＋T cells in normal healthy children, while the percentage of CD8＋T lymphocyte in critical cases was slightly lower than the normal reference value. In addition, compared with the reference value of CD8＋T cells in normal healthy children within 2 to 5 years old, the expression of CD8＋T cells was decreased in both of mild and critical patients within 2 to 5 years old,and the decrease relatively obvious in critical patients. Conclusion： In these two age groups between 15 to 24 months and 2 to 5 years, the expression of CD8＋T cells in different patients infected by CA16 varied less obviously, which might can be explained that the enough quantity of CD8＋T cells should play its immune effect on killing infected cells as normal. For the reason of the expression of CD8＋T cells is slightly lower or decreased in critical cases of these two age groups, it may be associated with the persistence infection of CA16 affected the expression of CD8＋T cells, which attribute to the lower killing effect of CD8＋T cells. It might be one of the immunopathologic factors resulted in the occurrence of neurological complication induced by CA16.