Evidence that a single peptide-MHC complex on a target cell can elicit a cytolytic T cell response.
Using a chemically homogeneous radiolabeled peptide of high specific activity (125I-QLSPYPFDL, 3.5 x 10(18) cpm per mole) we show that at a peptide concentration (5 pM) causing half-maximal lysis of target cells by a cytolytic T lymphocyte (CTL) clone that recognizes the peptide in association with Ld, a class I MHC protein, only 3 peptide molecules on average are bound by Ld per target cell. From the distribution of Ld on the target cells, we suggest that a single peptide-MHC complex per target cell can trigger activation of the T cell cytolytic response.
Sykulev
Y
Y
Center for Cancer Research, Department of Biology, Massachusetts Institute of Technology, Cambridge 02139, USA.
Joo
M
M
Vturina
I
I
Tsomides
T J
TJ
Eisen
H N
HN
D000595:Amino Acid Sequence; D000818:Animals; D002999:Clone Cells; D003601:Cytotoxicity Tests, Immunologic; D003602:Cytotoxicity, Immunologic / Q000187:drug effects; D000939:Epitopes / Q000737:chemistry / Q000378:metabolism; D006183:H-2 Antigens / Q000276:immunology; D015789:HLA-A2 Antigen / Q000276:immunology; D006649:Histocompatibility Antigens / Q000276:immunology*; D006801:Humans; D007700:Kinetics; D051379:Mice; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000276:immunology* / Q000494:pharmacology; D011485:Protein Binding / Q000276:immunology; D013602:T-Lymphocytes, Cytotoxic / Q000187:drug effects / Q000276:immunology*
D000939:Epitopes; D006183:H-2 Antigens; D015789:HLA-A2 Antigen; D006649:Histocompatibility Antigens; D010446:Peptide Fragments