Age-dependent appearance of non-major histocompatibility complex-restricted helper T cells Academic Article uri icon


MeSH Major

  • Aging
  • B-Lymphocytes
  • Major Histocompatibility Complex
  • T-Lymphocytes
  • T-Lymphocytes, Helper-Inducer


  • T cells which recognize antigen in association with self major histocompatibility complex (MHC) molecules are positively selected within the thymus. This results in skewing of the T-cell repertoire toward the recognition of antigenic peptides presented by self MHC molecules. While the thymus gland involutes at a relatively young age, bone marrow function and the size of the peripheral T-cell pool are maintained with age. We have investigated the MHC restriction of helper T-cell function for B-cell production of specific antibody in mice of different ages. Splenic helper T cells from 2- to 3-month old mice immunized with phosphocholine-keyhole limpet hemocyanin conjugate were MHC-restricted as defined by their capacity to induce phosphocholine-specific antibody synthesis by syngeneic but not by allogeneic B cells. In contrast, splenic T cells from immunized 18- to 20-month-old mice induced specific anti-phosphocholine antibodies by both syngeneic and allogeneic B cells. No evidence of polyclonal immunoglobulin synthesis was detected. The ability of T cells from old mice immunized with phosphocholine-keyhole limpet hemocyanin to induce phosphocholine-specific antibody synthesis by B cells from allogeneic mice was inhibited by T cells from immunized young mice. These findings suggest that non-MHC-restricted T-cell helper activity in old mice results from the loss of T cells, present in young mice, which suppress non-MHC-restricted helper cells.

publication date

  • December 15, 1993



  • Academic Article



  • eng

PubMed Central ID

  • PMC48055

PubMed ID

  • 8265615

Additional Document Info

start page

  • 11718

end page

  • 22


  • 90


  • 24