Evidence for self and nonself peptide partial agonists that prolong clonal survival of mature T cells in vitro.
When examining the effects of peptide analogues without proliferation-inducing activity on three human CD4+ T cell clones with distinct TCRbeta recognizing a nonself mycobacterial bacillus Calmette-Guerin a (BCGa) peptide fragment (EEYLILSARDVLAVVSK)/HLA-DR14 complex, we found that 1) stimulation of T cells with a one-residue-substituted analogue or a minimally homologous self peptide fragment derived from human connexin 26 (IMILVVAAKEVWGDEQA) can prolong the in vitro survival of T cells, in a clone specific-manner; 2) this prolongation is associated with the up-regulation of Bcl-xL without proliferation; and 3) these peptide-clone combinations are capable of inducing lymphokine secretion. Thus, peptide partial agonism may play a role in the survival of not only thymocytes but also mature T cells, in the absence of wild-type ligands.
Matsushita
S
S
Department of Neuroscience and Immunology, Kumamoto University Graduate School of Medical Sciences, Honjo, Japan.
Kohsaka
H
H
Nishimura
Y
Y
D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D002470:Cell Survival / Q000276:immunology; D002999:Clone Cells; D000072259:Connexin 26; D017630:Connexins / Q000276:immunology; D006801:Humans; D008222:Lymphokines / Q000378:metabolism; D009163:Mycobacterium bovis / Q000276:immunology; D010446:Peptide Fragments / Q000276:immunology*; D016693:Receptors, Antigen, T-Cell, alpha-beta / Q000032:analysis; D015854:Up-Regulation
D017630:Connexins; D008222:Lymphokines; D010446:Peptide Fragments; D016693:Receptors, Antigen, T-Cell, alpha-beta; D000072259:Connexin 26