儿童EB病毒相关噬血细胞淋巴组织细胞增生症NK细胞表面受体和CD107a表达

目的:研究儿童EB病毒相关噬血细胞淋巴组织细胞增生症（EBV-HLH）NK细胞表面受体和CD107a表达，为深入了解EBV-HLH发病机制提供理论依据。方法:选取2009年8月至2011年5月于北京儿童医院确诊为EBV-HLH、未接受过化学免疫治疗的住院患儿为EBV-HLH组，选取年龄、性别与EBV-HLH组1∶1匹配的健康查体儿童为正常对照组。应用流式细胞仪检测NK细胞表面受体、穿孔素及CD107a表达。予IL-2刺激后再次测定CD107a表达情况。结果:EBV-HLH组和正常对照组各8例。①两组NK细胞表面受体NKp30、NKp46、NKG2D、DNAM-1和2B4表达阳性率差异均无统计学意义，CD56+ NK细胞穿孔素表达率和CD8＋ T细胞穿孔素表达率差异均无统计学意义。②两组在IL-2刺激前CD107a、CD107a/K562、CD107a/2B4/P815、CD107a/NKG2D/P815和CD107a/2B4/NKG2D/P815表达率差异均无统计学意义。③EBV-HLH组在IL-2刺激前后CD107a表达差异无统计学意义；正常对照组IL-2刺激前后CD107a、CD107a/K562和CD107a/NKG2D/P815表达率差异有统计学意义。结论:EBV-HLH患儿NK细胞对IL-2的反应出现异常，可能与EBV-HLH的发生有关。

Expression of NK cell surface receptors and CD107a in Epstein-Barr virus associated hemophagocytic lymphohistiocytosis children

Objectives：The role of NK cell function as an etiological or prognostic factor in EBV-HLH remains unclear. The present study tried to investigate the expression of NK cell surface activating receptors and CD107a in EBV-HLH patients. Methods：EBV-HLH patients and age- and sex-matched normal controls were selected from August 2009 to May 2011 in Beijing Children′s Hospital. Multicolored immunofluorescence flowcytometric analysis was performed to detect NK cellsurface activating receptors, perforin and IL-2 stimulated NK cells in peripheral blood from EBV-HLH patients and controls. Results:Eight cases were enrolled in EBV-HLH group and 8 normal children were enrolled in control group. ①There was no statistical difference between EBV-HLH patients and normal controls in NK cell surface activating receptors (NKP30, NKP46, NKG2D, DNAM-1 and 2B4), perforin or basic CD107a expression (P>0.05). ②There was no statistical difference in basic CD107a, CD107a/K562, CD107a/2B4/P815, CD107a/NKG2D/P815 or CD107a/2B4/NKG2D/P815 expression between EBV-HLH group and control group. ③Basic CD107a expression, CD107a/K562 and CD107a/NKG2D/P815 expression in normal controls significantly changed 48 hours after IL-2 stimulation, while such difference was not seen in EBV-HLH patients (P>0.05). Conclusions:The present results indicated that there may be some defects in responding to IL-2 in EBV-HLH patients.