Patients with CTLA4 mutations present with autoimmune diseases, lymphoproliferation, and hypogammaglobulinemia, and a subset of patients developed Epstein-Barr virus (EBV)-associated malignancies, suggesting an impaired immune function against EBV. Here we investigated EBV infection in individuals with CTLA4 mutations. We measured EBV viral DNA in healthy individuals, individuals with autoimmune diseases, and individuals with CTLA4 mutations. In addition, we evaluated the numbers and function of EBV-specific T cells, invariant NKT cells, and NK cells. More than half of individuals with CTLA4 mutations including asymptomatic ones had detectable EBV DNA, which is a significantly higher frequency with higher viral loads compared with healthy and disease controls. However, individuals with CTLA4 mutations had almost normal immunity against EBV. Individuals with CTLA4 mutations have an increased susceptibility to Epstein-Barr virus infections. Asymptomatic viremia occurs at high frequencies, which can be persistent and can occur in unaffected individuals.

患有CTLA4突变的患者表现出自身免疫性疾病，淋巴增生和低血球蛋白血症，部分患者出现了与爱泼斯坦-巴尔病毒（EBV）相关的恶性肿瘤，表明针对EBV的免疫功能受损。在这里，我们调查了CTLA4突变个体的EBV感染。我们在健康个体，自身免疫性疾病个体和CTLA4突变个体中测量了EBV病毒DNA 。此外，我们评估了EBV特异性T细胞，不变NKT细胞和NK细胞的数量和功能。超过一半的CTLA4患者包括无症状突变在内的突变具有可检测的EBV DNA，与健康和疾病对照相比，它具有更高的频率和更高的病毒载量。但是，具有CTLA4突变的个体对EBV的免疫力几乎是正常的。具有CTLA4突变的个体对爱泼斯坦-巴尔病毒感染的敏感性增加。无症状病毒血症的发生频率很高，可以持续存在，并且可以在未受影响的个体中发生。