Cross-linking and Conformational Change in T-cell Receptors: Role in Activation and in Repertoire Selection
This extract was created in the absence of an abstract.
Excerpt
Self/non-self discrimination is the most important consequence of immunological recognition. Of cells participating in this central event, the CD4+ T lymphocytes appear to be the most important. In this paper, we use our studies on antigen recognition by cloned T-cell lines to explore two related issues. First, how does the T-cell receptor (TCR) recognize its ligand comprising a peptide fragment of foreign antigen bound to a class II major histocompatibility complex (MHC) molecule? Second, and more difficult, how can the same receptor be selected during its intrathymic ontogeny for the ability to recognize antigen only when presented by self class II MHC molecules?
The receptor for antigen on T cells comprises two highly variable chains termed α and β, bound to an invariant set of chains known as CD3. T cells recognizing antigen presented by class II MHC molecules express the co-receptor molecule CD4 on their cell surface. CD4 is...
