The bone marrow perisinusoidal niche for recirculating B cells and the positive selection of bone marrow-derived B lymphocytes

作者：Pillai Shiv^*; Cariappa Annaiah

来源：Immunology and Cell Biology, 2009, 87(1): 16-19.

DOI：10.1038/icb.2008.89

• perisinusoidal B cells
• follicular B cells
• positive selection
• lymphocyte development
• bone marrow
• secondary lymphoid organ

A unique 'second' niche for follicular B cells has been described in the extravascular compartment of the bone marrow surrounding vascular sinusoids. The occupancy of this niche by B cells presumably evolved to facilitate humoral immune responses to blood-borne pathogens. B cells appear to be sustained in this niche by bone marrow dendritic cells and are lost from this compartment in certain mutant mice. We discuss here what is known regarding the mechanisms of entry and egress of B cells from the perisinusoidal niche and also consider the function of the bone marrow as a secondary lymphoid organ. Although immature B cells can mature into follicular B cells in this niche as well as in the spleen, the lineage commitment event that accompanies positive selection of B cells occurs only in the spleen.

• 出版日期2009-1