Impaired regeneration of the peripheral B cell repertoire from bone marrow following lymphopenia in old mice.
Aging is associated with a decreased production of B cells by the bone marrow and an increased life-span of peripheral B cells. To determine whether the decreased bone marrow B cell production is linked to the increased life-span of B cells in old mice, B cell regeneration following lymphopenia was studied in young and old mice. The rate of bone marrow pre-B cell and of splenic B cell regeneration is slower in irradiated, old compared to irradiated, young recipients of young, congeneic bone marrow. This finding reflects an age-associated defect in the bone marrow microenvironment. As the bone marrow is the only source of a diverse population of B cells, we measured the diversity of the splenic B cell repertoire regenerated following drug-induced lymphopenia in old and young mice. The heterogeneity of mRNA size from IgH complementarity determining region 3 (CDR3) was more restricted in splenic B cells from old compared to young mice providing additional evidence for an age-associated impairment in B cell production by the bone marrow.
Li
F
F
Division of Geriatrics and Gerontology, Weill Medical College of Cornell University, New York 10021, USA.
Jin
F
F
Freitas
A
A
Szabo
P
P
Weksler
M E
ME
D000375:Aging / Q000276:immunology*; D000818:Animals; D001402:B-Lymphocytes / Q000502:physiology*; D001854:Bone Marrow Cells / Q000502:physiology*; D003520:Cyclophosphamide / Q000494:pharmacology; D005260:Female; D006412:Hematopoietic Stem Cells / Q000502:physiology; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D012038:Regeneration
D003520:Cyclophosphamide