Peripheral B cell subsets

Abstract

Our understanding of the origins and the biological functions of different peripheral B cell subsets continues to evolve. Some understanding has been obtained regarding the synergy between BCR-derived signals and other receptors and signaling pathways that drive the development of follicular, marginal zone, and B-1 B cells, but this remains a complex and poorly understood issue. More recent information regarding the origins of B-1 and B-2 B cells, the ability of follicular B cells to mature both in the bone marrow and the spleen, the existence of a definable precursor for MZ B cells, and the ability of follicular B cells to occupy two distinct niches are all highlighted in this review.

Figure 1. Peripheral B cell maturation from the bone marrow

Past (A) and current (B) models for developmental stages in peripheral B cell maturation form the marrow are shown. Question marks indicate predicted precursor-successor relationships that have yet to be adequately tested. Cell surface markers employed to distinguish each population are summarized in Table 1.

Figure 2. Resolution of developing and mature subpopulations of splenic B cells

Splenocytes from a single 8-week old female C57BL/6 mouse were stained in a single tube with antibodies to the indicated cell surface molecules before analysis of 200,000 events on an LSRII flow cytometer. All non-viable cells were eliminated from this analysis by gating on cells that failed to stain with the UV-excited DNA dye DAPI, and myeloid-lineage cells were eliminated by gating on CD11b⁻ Gr-1⁻ cells (gates not shown). CD19⁺ cells were identified as shown (left-most plot) and three gating strategies were employed to identify the indicated subsets. Gating strategies are from Cariappa et al. (top) (30), Martin and Kearney, and Srivastava et al., (middle) (29, 31), or Allman et al., (bottom) (26).