Premium
Altered superantigenic ligands demonstrate the quantitative nature of T‐cell activation
Author(s) -
Hayball John D,
Lake Richard A
Publication year - 2000
Publication title -
immunology and cell biology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.999
H-Index - 104
eISSN - 1440-1711
pISSN - 0818-9641
DOI - 10.1046/j.1440-1711.2000.00971.x
Subject(s) - superantigen , t cell receptor , cd28 , t cell , context (archaeology) , clone (java method) , receptor , enterotoxin , microbiology and biotechnology , biology , agonist , phenotype , partial agonist , chemistry , immunology , genetics , gene , immune system , escherichia coli , paleontology
In a recent study, a superantigen mutated in the TCR binding site (staphylococcal enterotoxin B (SEB)Δ61Y) was described, which behaved as a partial agonist for a Vβ17‐expressing T‐cell clone. Evidence is now presented to demonstrate that there is distinct heterogeneity in the response of primary T cells to this protein. Some Vβ17 T cells responded to SEBΔ61Y by modulating surface receptor expression consistent with activation, and by proliferating. Other Vβ17 T cells did not proliferate, nor did they display a receptor expression phenotype consistent with activation. However, when repeatedly exposed to the altered superantigen, some of these non‐responders entered cell cycle. This pattern of responses was not recapitulated by providing additional costimulation via CD28, although such treatment did induce some of the ‘unresponsive’ Vβ17 T cells to upregulate the IL‐2 receptor, indicative of partial activation. It was also found that the heterogeneous pattern could be replicated using very low doses of native SEB. The data are discussed in the context of models of T‐cell activation in which differences in TCR ligand affinity and dose determine qualitatively different response phenotypes.