Spleen

Population

Biology

B-1 cell

Antibody

Stromal cell

Immunology

T cell

Marginal zone

B cell

Bone marrow

Cell biology

Cancer research

Antigen-presenting cell

Medicine

Immune system

Environmental health

Nature Communications

At present, it is not clear how memory B lymphocytes are maintained over time, and whether only as circulating cells or also residing in particular tissues. Here we describe distinct populations of isotype-switched memory B lymphocytes (Bsm) of murine spleen and bone marrow, identified according to individual transcriptional signature and B cell receptor repertoire. A population of marginal zone-like cells is located exclusively in the spleen, while a population of quiescent Bsm is found only in the bone marrow. Three further resident populations, present in spleen and bone marrow, represent transitional and follicular B cells and B1 cells, respectively. A population representing 10-20% of spleen and bone marrow memory B cells is the only one qualifying as circulating. In the bone marrow, all cells individually dock onto VCAM1 + stromal cells and, reminiscent of resident memory T and plasma cells, are void of activation, proliferation and mobility.

Discrete populations of isotype-switched memory B lymphocytes are maintained in murine spleen and bone marrow