This study aimed to investigate the proportion of surface activation markers on natural killer (NK) cells in children with infectious mononucleosis (IM) and to explore its clinical relevance. A total of 17 children hospitalized with IM were included in this study as the experimental group. Meanwhile, healthy children matched for age and gender served as controls. First, we isolated peripheral blood mononuclear cells from children with IM and healthy children. Then, NK cell surface markers were stained with monoclonal antibodies and analyzed by flow cytometry. The results showed that the percentage of CD3⁻CD16⁺ NK cells was higher in peripheral blood lymphocytes from children with IM than that from healthy children (t = −4.52, P < 0.05). And the expression of the surface activation markers CD69 and CD25 on CD3⁻CD16⁺ NK cells was also higher in children with IM (t = −7.729, P < 0.05; t = −5.068, P < 0.05). There was a positive correlation between the percentage of CD3⁻CD16⁺ NK cells in peripheral blood and the duration of fever in children with IM (r = 0.530, P < 0.05). Therefore, the proportion of NK cell subsets in children's peripheral blood changes in the acute phase of IM, suggesting that NK cells enhance their cytotoxicity and play a role in the control of infection in children with IM. Higher levels of CD3⁻CD16⁺ NK cells and the association with disease progression suggest that these cells might be a useful index to help evaluate the disease course.

中文翻译：

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儿童传染性单核细胞增多症CD3-CD16+ NK细胞表面活化标志物及其与临床表现的相关性研究

本研究旨在调查传染性单核细胞增多症 (IM) 儿童自然杀伤 (NK) 细胞表面活化标志物的比例，并探讨其临床相关性。本研究共纳入 17 名因 IM 住院的儿童作为实验组。同时，年龄和性别匹配的健康儿童作为对照。首先，我们从患有 IM 的儿童和健康儿童中分离出外周血单个核细胞。然后，用单克隆抗体对 NK 细胞表面标志物进行染色，并通过流式细胞术进行分析。结果显示，IM患儿外周血淋巴细胞CD3 ^- CD16 ⁺ NK细胞百分比高于健康患儿（t  =-4.52，P < 0.05)。CD3 ^- CD16 ⁺ NK细胞表面活化标志物CD69和CD25在IM患儿中的表达也较高（t  =-7.729，P  <0.05；t  =-5.068，P  <0.05）。IM患儿外周血CD3 ^- CD16 ⁺ NK细胞百分比与发热持续时间呈正相关（r  =0.530，P < 0.05)。因此，IM 急性期儿童外周血中 NK 细胞亚群的比例发生变化，提示 NK 细胞增强了其细胞毒性，在 IM 儿童感染控制中发挥作用。较高水平的 CD3 ^- CD16 ⁺ NK 细胞以及与疾病进展的关联表明这些细胞可能是帮助评估疾病进程的有用指标。