血小板自身抗体的流式细胞术检测与意义

目前血小板自身抗体的测定方法较为复杂,同时需要较多的血量,因此给儿科临床应用带来一定困难。本文拟应用流式细胞术建立一种简便、快捷、敏感的检测血小板相关抗体的方法。应用荧光素化的羊抗人Ｆ(ａｂ)２段ＩｇＧ抗体结合血小板表面的抗体,应用荧光素化的羊抗鼠ＩｇＧ抗体作为阴性对照。即以直接法测定血小板表面结合的ＩｇＧ。应用流式细胞术测定血小板的平均荧光强度。血小板荧光强度(ＭＦＩ)反映血小板表面ＰＡＩｇＧ的水平。测定正常人和特发性血小板减少性紫癜患儿的血小板平均荧光强度。结果显示:正常对照组的血小板平均荧光强度(ＭＦＩ)为２３．６７±９．１０(道数)。３１例ＩＴＰ组的ＭＦＩ为１０３．６３±３１．４１(道数)。ＩＴＰ病人的血小板荧光阳性率为９０%。治疗有效的病人,随血小板计数的上升,血小板荧光强度逐渐下降。因此,流式细胞术测定血小板抗体是一种快速、简便灵敏的ＰＡＩｇＧ检测方法,可用于免疫性血小板减少性紫癜的辅助诊断和疗效观察。

MEASUREMENT OF PLATELET ASSOCIATED ANTIBODY BY FLOW CYTOMETRY AND IT'S CLINICAL SIGNIFICANCE

At present, the measurement of platelet autoantibody is diffcult to perform and a lot of blood is needed, especially diffcult in pediatric clinic. We try to find a simple and fast method to detect platelet antibody by flow cytometry. Methods: To measure platelet autoantibody by flow cytometry, fluensined F (ab)2 fragment goat anti - human immunoglobin was used for detecting platelet antibody in the surface of platelet. Goat anti - mice immunoglobin was used as the negative control. This is the direct method to investigate platelet - bound immunoglobin G. The mean fluorescence intensity(MFI) of platelet were calculated and MFI reflects the content of PAIgG in the surface of platelet MFI of platelet in patients with TTP as well as the normal controls were measured. Results: 30 cases of healthy children were taken as the normal controls. MFI of platelet in normal control was 23.67 ± 9.10(x ± SD). MFI of platelet in patients with ITP was 103.63 ± 31.41. MFI of platelet exceeding X ± 2SD (mean ± 2 × standard deviation. ) was considered as positive. 90% patients with ITP had positive results. For those patients who were treated effectively, the MFI graduraly decreased. Conclusions: Flow cytometry is a quick and sensitive assay for detection of PAIgG of platelets and can be used as routine method in diagnosis and observation of therapeutic effects in ITP patients.