Cossarizza A, Stent G, Mussini C, Paganelli R, Borghi V, Nuzzo C, Pinti M, Pedrazzi J, Benatti F, Esposito R, Røsok B, Nagata S, Vella S, Franceschi C, De Rienzo B
Department of Biomedical Sciences, University of Modena School of Medicine, Italy.
AIDS. 2000 Mar 10;14(4):345-55. doi: 10.1097/00002030-200003100-00007.
To analyze the role of CD95/CD95 ligand (CD95L) expression and functionality in peripheral blood lymphocytes (PBL) during primary, acute HIV syndrome (AHS) and in the subsequent period.
Twelve patients were studied during the acute phase of the viral infection and most were followed for some months.
Cell culture and cytotoxicity assays based upon 51Cr release and flow cytometry were used to evaluate cell killing via CD95 molecule, flow cytometry to assess surface antigens, enzyme-linked immunosorbent assay (ELISA) for the determination of soluble CD95 and CD95L plasma levels, quantitative competitive (QC) reverse transcription polymerase chain reaction (RT-PCR) with an original RNA competitor for the analysis of CD95L mRNA expression and QC RT-PCR for determining plasma viral load.
The analysis of PBL during this phase revealed that almost all cells, including CD8 T cells with a virgin phenotype, B lymphocytes and natural killer cells displayed CD95 molecules on the plasma membrane. Activation of CD95 on the surface of isolated lymphocytes by anti-CD95 monoclonal antibodies or binding to CD95L induced rapid apoptosis. However, CD95L mRNA was not expressed in PBL from these patients and was poorly inducible. Soluble CD95 was found in the plasma of all patients, but only in a few at high levels, even some months after seroconversion. In contrast, soluble CD95L was detected in only one patient, this occurring after the symptomatic period. For 10 of the 12 patients, expression of CD95 on the cell membrane or in the plasma did not correlate with the plasma viral load, which varied widely from patient to patient. Further, plasma levels of soluble CD95 were not altered by decreased lymphocyte activation or by efficient antiretroviral therapy.
In patients experiencing an acute, primary HIV infection, a prolonged deregulation of the CD95/CD95L system may exist, which is probably not entirely related to virus production but may contribute to the pathogenesis of the disease. The hypothesis can be put forward that a complex balance exists between proapoptotic events (increase in CD95 expression), probably triggered by the host as a method to limit viral production, and antiapoptotic events (decrease in CD95L expression) probably triggered by the virus as a way to increase its production and survival.
分析原发性急性HIV综合征（AHS）期间及随后外周血淋巴细胞（PBL）中CD95/CD95配体（CD95L）表达及功能的作用。
对12例患者在病毒感染急性期进行研究，多数患者随访数月。
采用基于51Cr释放的细胞培养和细胞毒性试验以及流式细胞术评估通过CD95分子的细胞杀伤作用，用流式细胞术评估表面抗原，用酶联免疫吸附测定（ELISA）法测定可溶性CD95和CD95L血浆水平，用带有原始RNA竞争物的定量竞争性（QC）逆转录聚合酶链反应（RT-PCR）分析CD95L mRNA表达，并用QC RT-PCR测定血浆病毒载量。
此阶段对PBL的分析显示，几乎所有细胞，包括具有初始表型的CD8 T细胞、B淋巴细胞和自然杀伤细胞，在质膜上均表达CD95分子。用抗CD95单克隆抗体激活分离淋巴细胞表面的CD95或与CD95L结合可诱导快速凋亡。然而，这些患者的PBL中未表达CD95L mRNA，且诱导性较差。所有患者血浆中均发现可溶性CD95，但只有少数患者的水平较高，甚至在血清转化后数月也是如此。相比之下，仅在1例患者的症状期后检测到可溶性CD95L。12例患者中有10例，细胞膜或血浆中CD95的表达与血浆病毒载量无关，不同患者的病毒载量差异很大。此外，淋巴细胞激活减少或高效抗逆转录病毒治疗均未改变可溶性CD95的血浆水平。
在原发性急性HIV感染患者中，可能存在CD95/CD95L系统的长期失调，这可能不完全与病毒产生相关，但可能参与疾病的发病机制。可以提出这样的假说：促凋亡事件（CD95表达增加）可能由宿主触发以限制病毒产生，而抗凋亡事件（CD95L表达减少）可能由病毒触发以增加其产生和存活，二者之间存在复杂的相互作用。
