How do B cells mature and gain tolerance? This review provides a comprehensive overview of B cell development, a crucial process for generating functional peripheral subsets from hematopoietic stem cells. It focuses on key stages in the mouse bone marrow. The review discusses the earliest stages of commitment, pre-B cell receptor selection, and B cell tolerance during the immature-to-mature B cell transition. It contrasts hematopoiesis and pre-B selection between the fetal liver and adult bone marrow, linking fetal development to B-1/CD5+ B cells. Finally, it examines the factors influencing the generation and maintenance of CD5+ cells, a distinct peripheral B cell population enriched for autoreactive specificities. This knowledge is vital for understanding immune system function and developing targeted therapies for immunologic diseases.
As a contribution to the _Annual Review of Immunology_, this paper aligns perfectly with the journal's scope of providing in-depth analyses of immunological processes. It offers a broad and insightful examination of B cell development, a central topic in immunology. Its citation by later research underscores its significance in the field.