Measles outbreaks have threatened the global elimination and eradication of measles in recent years. Measles virus (MeV)-specific antibodies are successful in clearing MeV infection. Follicular helper T (Tfh) cells play a crucial role in promoting antibody production. This study investigated the potential role of Tfh cells in peripheral blood mononuclear cells (PBMCs) from children with acute MeV infection. The frequencies of CXCR5+CD4+ Tfh, ICOShigh Tfh, and PD-1high Tfh cells in PBMCs and levels of IL-6 and IL-21 in plasma were significantly elevated in patients with acute MeV infection. Moreover, a positive correlation was discovered among the frequency of ICOShigh Tfh cells, plasma levels of IL-21 and optical density (OD) values of MeV-specific IgM antibodies in the patients with acute MeV infection. However, elevated plasma MeV-specific NAb titres were not associated with the frequency of Tfh, ICOShigh Tfh, or PD-1high Tfh cells in the patients with acute MeV infection. These results suggest that an elevated Tfh cell frequency and associated molecules possibly play a key role in children with acute MeV infection, which contributes to the prevention and treatment of MeV infection in children.

中文翻译：

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急性麻疹感染儿童外周血中滤泡辅助性 T 细胞扩增增加。

近年来，麻疹暴发威胁到全球消灭和根除麻疹。麻疹病毒 (MeV) 特异性抗体可成功清除 MeV 感染。滤泡辅助性 T (Tfh) 细胞在促进抗体产生方面起着至关重要的作用。本研究调查了 Tfh 细胞在急性 MeV 感染儿童的外周血单核细胞 (PBMC) 中的潜在作用。急性 MeV 感染患者 PBMC 中 CXCR5+CD4+Tfh、ICOShigh Tfh 和 PD-1high Tfh 细胞的频率以及血浆中 IL-6 和 IL-21 的水平显着升高。此外，在急性 MeV 感染患者中发现 ICOShigh Tfh 细胞的频率、IL-21 的血浆水平和 MeV 特异性 IgM 抗体的光密度 (OD) 值之间存在正相关。然而，在急性 MeV 感染患者中，血浆 MeV 特异性 NAb 滴度升高与 Tfh、ICOShigh Tfh 或 PD-1high Tfh 细胞的频率无关。这些结果表明，升高的 Tfh 细胞频率和相关分子可能在儿童急性 MeV 感染中起关键作用，这有助于儿童 MeV 感染的预防和治疗。