Lymphopoietic Potential of Bone Marrow Cells from Aged Mice: Comparison of the Cellular Constituents of Bone Marrow from Young and Aged Mice

Abstract

Cell transfer systems have been used to study the capacity of aged mouse bone marrow to generate functional bone marrow-derived (B) lymphocytes. The progeny of the B lymphocytes in these systems were detected as anti-sheep erythrocyte antibody-producing cells. These in vivo transfer systems suggested that bone marrow from aged mice contained a significantly greater number of differentiated immunocompetent cells than marrow from young mice. Increased frequencies of theta and IgM-bearing cells in the aged marrow were detected by immunofluorescent techniques. Immunofluorescent studies and cell transfer systems demonstrated that pre-treatment of the aged bone marrow donors with anti-lymphocyte serum physically depleted the marrow of contaminating thymus-derived lymphocytes and reduced the relative responsiveness of the cells. Anti-lymphocyte serum did not decrease the number of bone marrow stem cells as measured by the colony-forming unit assay. The results suggested an age-associated alteration in lymphocyte circulation dynamics and a decreased ability of aged marrow to generate B lymphocytes.