Human B cells could be divided into four classical subsets based on CD27 and immunoglobulin (Ig)D expression. Distinct from the other three well-studied subsets, CD27⁻IgD⁻ B cells, also termed as double-negative (DN) B cells, have long been neglected. However, in recent years emerging evidence shows that DN B cells are unique memory B cells with important functions. They are expanded in a variety of diseases, especially in autoimmune diseases, contributing to the disease pathogenesis. Here, we briefly review the studies on DN B cells, including their origins, characteristics, subsets and roles in diseases, to try to bring new insights into this under-recognized B cell subset.

中文翻译：

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双阴性 (DN) B 细胞：自身免疫中认识不足的效应记忆 B 细胞亚群

根据 CD27 和免疫球蛋白 (Ig)D 的表达，人类 B 细胞可分为四个经典亚群。与其他三个经过充分研究的亚群不同，CD27 ^- IgD ^- B 细胞，也称为双阴性 (DN) B 细胞，长期以来一直被忽视。然而，近年来新出现的证据表明，DN B细胞是具有重要功能的独特记忆B细胞。它们在多种疾病中得到扩展，特别是在自身免疫性疾病中，有助于疾病的发病机制。在这里，我们简要回顾了对 DN B 细胞的研究，包括它们的起源、特征、亚群和在疾病中的作用，试图为这个未被充分认识的 B 细胞亚群带来新的见解。