• Antigen presentation;
  • T cell;
  • macrophage;
  • cytochrome

ABSTRACT: Data are presented that suggest that the activation of cytochrome c-specific T lymphocytes is dependent on the integrity of the three-dimensional structure of the protein antigen. These results were obtained both at the population level and at the clonal level. The capacity of the native and denatured forms of cytochrome c to activate a different set of T cell clones was observed both in vivo and in vitro. These results could be explained by the differential capacity of macrophages to process and/or present the two forms of cytochrome c.