Distinct footprints of TCR engagement with highly homologous ligands.
T cell receptor engagement promotes proliferation, differentiation, survival, or death of T lymphocytes. The affinity/avidity of the TCR ligand and the maturational stage of the T cell are thought to be principal determinants of the outcome of TCR engagement. We demonstrate in this study that the same mouse TCR preferentially uses distinct residues of homologous peptides presented by the MHC molecules to promote specific cellular responses. The preference for distinct TCR contacts depends on neither the affinity/avidity of TCR engagement (except in the most extreme ranges), nor the maturity of engaged T cells. Thus, different portions of the TCR ligand appear capable of biasing T cells toward specific biological responses. These findings explain differences in functional versatility of TCR ligands, as well as anomalies in the relationship between affinity/avidity of the TCR for the peptide/MHC and cellular responses of T cells.
Santori
Fabio R
FR
Michael Heidelberger Division of Immunology, Department of Pathology and New York University Cancer Center, New York University School of Medicine, New York, NY 10016, USA.
Holmberg
Kaisa
K
Ostrov
David
D
Gascoigne
Nicholas R J
NR
Vukmanović
Stanislav
S
D000595:Amino Acid Sequence; D000818:Animals; D017951:Antigen Presentation; D018604:Epitope Mapping; D018984:Epitopes, T-Lymphocyte / Q000737:chemistry / Q000502:physiology*; D008024:Ligands; D051379:Mice; D008822:Mice, Transgenic; D008958:Models, Molecular; D010455:Peptides / Q000138:chemical synthesis / Q000276:immunology*; D011485:Protein Binding; D023302:Protein Footprinting; D011948:Receptors, Antigen, T-Cell / Q000235:genetics / Q000378:metabolism* / Q000502:physiology; D013329:Structure-Activity Relationship; D016176:T-Lymphocyte Subsets
D018984:Epitopes, T-Lymphocyte; D008024:Ligands; D010455:Peptides; D011948:Receptors, Antigen, T-Cell