Institute of Medical Microbiology and Immunology, University of Aarhus, Denmark.
Hum Immunol. 2010 Jan;71(1):29-35. doi: 10.1016/j.humimm.2009.09.355.
Natural killer (NK) cells are essential components of the immune response against human cytomegalovirus (HCMV). As NK cells are part of the innate immune system providing an immediate defense against pathogens, short-term exposure to HCMV-infected cells may induce changes in the phenotype and function of these cells. To identify immediate reactions of NK cells to HCMV, we co-cultured peripheral blood mononuclear cells with HCMV-infected fibroblasts for 24 and 72 hours. A distinct, HCMV-mediated, proportional enlargement of a subset of NK cells expressing CD94/NKG2A was sustained throughout the period of incubation. As preceding studies have shown that HCMV can cause an increase in CD94/NKG2C(+) NK cells, our results were surprising. The NK cells showed intense upregulation of the early activation marker CD69 in response to HCMV. The CD94/NKG2A(+) NK cells demonstrated the highest expression of CD69. Studies of HCMV-induced interferon-gamma expression after 24 hours of co-culture showed that this cytokine was almost exclusively produced by the CD94/NKG2A(+) subset of NK cells. In summary, our data demonstrate that HCMV induces an immediate proportional enlargement of a functionally active CD94/NKG2A expressing subset of NK cells.
自然杀伤 (NK) 细胞是人体巨细胞病毒 (HCMV) 免疫反应的重要组成部分。由于 NK 细胞是先天免疫系统的一部分，能够对病原体提供即时防御，因此短期暴露于 HCMV 感染的细胞可能会导致这些细胞的表型和功能发生变化。为了确定 NK 细胞对 HCMV 的即时反应，我们将外周血单核细胞与 HCMV 感染的成纤维细胞共培养 24 小时和 72 小时。在整个孵育期间，持续存在一组表达 CD94/NKG2A 的 NK 细胞的显著、由 HCMV 介导的比例增大。由于先前的研究表明 HCMV 可导致 CD94/NKG2C(+) NK 细胞增加，因此我们的结果令人惊讶。NK 细胞对 HCMV 的反应强烈上调早期激活标志物 CD69。CD94/NKG2A(+) NK 细胞表现出最高水平的 CD69 表达。共培养 24 小时后研究 HCMV 诱导的干扰素 -γ 表达表明，这种细胞因子几乎完全由 CD94/NKG2A(+) NK 细胞亚群产生。总之，我们的数据表明 HCMV 诱导具有功能活性的 CD94/NKG2A 表达 NK 细胞亚群的即时比例增大。
