"Altered-self" or "near-self" in the positive selection of lymphocyte repertoires?
Positive selection of lymphocyte repertoires is now recognized as applying to both B and T cells. However, much of the early literature on positive selection focussed on cell-mediated immunity (T cells), which biased consideration of its general biological role. The term "altered-self," which initially captured the idea of self (i.e. MHC) altered by the addition of what was later found to be a peptide fragment, has not proven robust and may now be clouding our understanding. It is recommended that the term "near-self" be reintroduced since it captures the essence of the probable underlying adaptive process-sub-threshold self-reactivity to countermand rapid pathogen mutation.
Forsdyke
Donald R
DR
Department of Biochemistry, Queen's University, Botterall Hall, Stuart Street, Kingston, Ontario, Canada K7L 3N6. forsdyke@post.queensu.ca
D000818:Animals; D001323:Autoantibodies / Q000276:immunology; D001324:Autoantigens / Q000276:immunology; D016175:B-Lymphocyte Subsets / Q000276:immunology*; D017637:Clonal Deletion; D006801:Humans; D007111:Immunity, Cellular; D038041:Lymphopoiesis; D008285:Major Histocompatibility Complex / Q000276:immunology; D017634:Self Tolerance / Q000276:immunology*; D016176:T-Lymphocyte Subsets / Q000276:immunology*
D001323:Autoantibodies; D001324:Autoantigens