B cell precursors are decreased in senescent BALB/c mice, but retain normal mitotic activity in vivo and in vitro

Clin Immunol Immunopathol. 1991 May;59(2):301-13. doi: 10.1016/0090-1229(91)90026-7.


The numbers of phenotypic (sIg- Ly5[220]+) and functional B cell precursors were significantly reduced in the bone marrow of senescent (22-24 months old) BALB/c mice when compared to their young (2-4 months old) cohorts. Little alteration in the numbers of B cell precursors occurred during the first 12 months of life in this strain. In contrast, an accelerated loss of B cell precursors between 15 and 18 months of age was observed. In particular, the levels of small Ly5(220)+ B cell precursors were decreased with advanced age, although a decline in numbers of large sIg- Ly5(220)+ B cell precursors was also evident. The percentages of large sIg- Ly5(220)+ B cell precursors in (S + G2/M) stages of cell cycle were similar (e.g., 60-80%) in aged and young BALB/c mice. Importantly, Ly5(220)+ pre-B cells from both young and aged BALB/c mice, either present in vivo or derived from Ly5(220)- cells in vitro, were capable of proliferation in response to rIL-7. These observations suggest that the aging process results in a progressive decline in the numbers of pre-B cells; however, this apparently is not due to failure of B lineage precursor cells to respond to growth mediators either in vivo or in vitro.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Aging / immunology*
  • Animals
  • Antigens, Ly / analysis
  • B-Lymphocytes / physiology*
  • Bone Marrow Cells
  • Hematopoietic Stem Cells / physiology*
  • Interleukin-7 / pharmacology
  • Leukocyte Count
  • Male
  • Mice
  • Mice, Inbred BALB C
  • Mitosis
  • Receptors, Antigen, B-Cell / analysis
  • Recombinant Proteins / pharmacology


  • Antigens, Ly
  • Interleukin-7
  • Receptors, Antigen, B-Cell
  • Recombinant Proteins