Functions of double‐negative B cells in autoimmune diseases, infections, and cancers
Michael King Yung Chung, Lanqi Gong, Dora Lai‐Wan Kwong, Victor Lee, Anne W.M. Lee, Xin‐Yuan Guan, Ngar‐Woon Kam, Wei Dai
Abstract
Abstract Most mature B cells can be divided into four subtypes based on the expression of the surface markers IgD and CD27: IgD + CD27 − naïve B cells, IgD + CD27 + unswitched memory B cells, IgD − CD27 + switched memory B cells, and IgD − CD27 − double‐negative (DN) B cells. Despite their small population size in normal peripheral blood, DN B cells play integral roles in various diseases. For example, they generate autoimmunity in autoimmune conditions, while these cells may generate both autoimmune and antipathogenic responses in COVID‐19, or act in a purely antipathogenic capacity in malaria. Recently, DN B cells have been identified in nasopharyngeal carcinoma and non‐small‐cell lung cancers, where they may play an immunosuppressive role. The distinct functions that DN B cells play in different diseases suggest that they are a heterogeneous B‐cell population. Therefore, further study of the mechanisms underlying the involvement of DN B cells in these diseases is essential for understanding their pathogenesis and the development of therapeutic strategies. Further research is thus warranted to characterize the DN B‐cell population in detail.