Nkambule Bongani B, Davison Glenda Mary, Ipp Hayley
Divisions of Haematology, Department of Pathology, Stellenbosch University and NHLS, Tygerberg, South Africa.
Department of Biomedical sciences, Faculty of Health and wellness sciences, Cape Peninsula University of Technology, Bellville, South Africa.
Thromb Res. 2015 Jun;135(6):1131-9. doi: 10.1016/j.thromres.2015.01.031. Epub 2015 Feb 4.
Human immunodeficiency virus (HIV) induces inflammation and platelet activation. People living with HIV are at increased risk of thrombotic events. Activated platelets link inflammation with thrombosis. However platelet function in HIV remains unclear. P-selectin (CD62P), a marker of platelet activation, and platelet glycoprotein GPIV (CD36) a marker of platelet aggregation, can be measured using flow cytometry. We raise a hypothesis that HIV alters the signalling pathways involved in normal platelet function. We evaluated platelet function in HIV using a whole blood platelet flow cytometry based assay.
Fifty-eight antiretroviral therapy naïve HIV infected and 38 HIV negative individuals were recruited in a clinic in Cape Town. Platelet surface CD36 and CD62P were measured using flow cytometry. These were then correlated with CD4 count, viral load and %CD38 on CD8+ T-cells. Platelet function was evaluated using adenosine diphosphate, arachidonic acid and collagen at varying concentrations.
The HIV group showed increased levels of %CD62P (median 5.51[3.03- 10.11] vs. Control group 2.14[0.19 - 3.59], p<0.0001. This correlated with Viral load (r=0.336, P=0.008). The HIV group also showed increased levels of platelet %CD36 21.93[11.03-44.92] vs. Control 16.15[2.24-25.37], p=0.0087) which correlated with viral load (r=0.398, p=0.024). The HIV group showed a hyper response to AA and collagen at various concentrations. Notably, the HIV group only showed a hyper response to ADP at a maximal concentration of 20 μM (median CD62P MFI, 1.91[1.64-4.95] vs. Control 1.75[1.45-2.44] p=0.0279.
The measurement of platelet function using flow cytometry is a rapid technique for the evaluation of platelet signalling pathways that may be modified in HIV infected individuals.
人类免疫缺陷病毒（HIV）可引发炎症和血小板活化。感染HIV的人发生血栓事件的风险增加。活化的血小板将炎症与血栓形成联系起来。然而，HIV患者的血小板功能仍不明确。血小板活化标志物P-选择素（CD62P）和血小板聚集标志物血小板糖蛋白GPIV（CD36）可通过流式细胞术进行检测。我们提出一个假设，即HIV会改变正常血小板功能所涉及的信号通路。我们使用基于全血血小板流式细胞术的检测方法评估了HIV患者的血小板功能。
在开普敦的一家诊所招募了58名未接受过抗逆转录病毒治疗的HIV感染者和38名HIV阴性个体。使用流式细胞术检测血小板表面的CD36和CD62P。然后将这些指标与CD4细胞计数、病毒载量以及CD8+T细胞上的%CD38进行相关性分析。使用不同浓度的二磷酸腺苷、花生四烯酸和胶原评估血小板功能。
HIV组的%CD62P水平升高（中位数5.51[3.03 - 10.11]，对照组为2.14[0.19 - 3.59]，p<0.0001）。这与病毒载量相关（r = 0.336，P = 0.008）。HIV组的血小板%CD36水平也升高（21.93[11.03 - 44.92]，对照组为16.15[2.24 - 25.37]，p = 0.0087），且与病毒载量相关（r = 0.398，p = 0.024）。HIV组在不同浓度的花生四烯酸和胶原刺激下表现出高反应性。值得注意的是，HIV组仅在最大浓度为20μM的二磷酸腺苷刺激下表现出高反应性（CD62P平均荧光强度中位数，1.91[1.64 - 4.95]，对照组为1.75[1.45 - 2.44]，p = 0.0279）。
使用流式细胞术检测血小板功能是一种快速评估血小板信号通路的技术，这些信号通路在HIV感染者中可能会发生改变。
