Linking age-related defects in B lymphopoiesis to the aging of hematopoietic stem cells.
B cell genesis declines with age, but at what stage and why remains unclear. Previous studies attribute the decline in B cell production in aged mice to both environmental and cell-intrinsic defects that impact mid-to-late stream B cell precursors. However, mounting evidence suggests that the aging process may also negatively affect the earliest phases of B cell development. We review past studies on the B cells and aging question, discuss recent data suggesting that age-associated defects in B cell development reflect deficiencies in hematopoietic stem cell-proximal progenitor pools, and provide an integrative model that will hopefully facilitate further studies into this complex problem.
Department of Pathology and Laboratory Medicine, University of Pennsylvania School of Medicine, 269 John Morgan Building, 36th and Hamilton Walk, Philadelphia, PA 19104, USA.
Juli P
JP
Miller
David
D
Allman
D000375:Aging / Q000276:immunology*; D000818:Animals; D001402:B-Lymphocytes / Q000166:cytology / Q000276:immunology*; D016922:Cellular Senescence / Q000276:immunology*; D006412:Hematopoietic Stem Cells / Q000276:immunology*; D038041:Lymphopoiesis / Q000276:immunology*