A sequence pattern common to T cell epitopes.

An analysis of the known cytotoxic and helper T cell epitopes has revealed similarity within their primary sequences. These similar motifs, characteristic of the known determinants, have been incorporated into predictive templates that have been used successfully to define eight helper and three cytotoxic epitopes in four different proteins. When the defined epitopes are segregated by restriction element, allele specific subpatterns emerge centering around the general pattern. The presence of similarities argues that the binding of peptide antigens to class I and class II is similar in nature. In addition, these motifs can be used to predict accurately areas within proteins capable of being recognized by individual MHC class I and class II molecules.