Spontaneous proliferation, a response of naive CD4 T cells determined by the diversity of the memory cell repertoire.
T cell numbers are maintained within narrow ranges in vivo. Introduction of naïve cells into lymphopenic environments results in proliferation and differentiation driven by the recognition of peptide/MHC complexes and by cytokine signaling. This process, often described as homeostatic proliferation, is here referred to as spontaneous proliferation. We show that, although the presence of memory CD4 T cells of broad repertoire efficiently inhibits proliferation/differentiation of naïve CD4 T cells, a memory population of similar size comprised of cells with a repertoire of limited diversity fails to do so, implying that cells of a given specificity prevent responses of cells of the same or related specificity. This finding suggests that the immune system has evolved mechanisms to attain a memory cell repertoire of great diversity independently of foreign antigens.
Min
Booki
B
Laboratory of Immunology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892-1892, USA.
Foucras
Gilles
G
Meier-Schellersheim
Martin
M
Paul
William E
WE
D000818:Animals; D015496:CD4-Positive T-Lymphocytes / Q000166:cytology / Q000276:immunology / Q000502:physiology*; D002455:Cell Division / Q000502:physiology; D006706:Homeostasis / Q000502:physiology; D007156:Immunologic Memory / Q000276:immunology / Q000502:physiology*; D008231:Lymphopenia / Q000235:genetics; D051379:Mice; D008822:Mice, Transgenic; D011948:Receptors, Antigen, T-Cell / Q000235:genetics; D015375:Receptors, Interleukin-2 / Q000502:physiology
D011948:Receptors, Antigen, T-Cell; D015375:Receptors, Interleukin-2