The factors that may cause antigen-presenting cells to alter the patte
rn of protein Processing and presentation to autoreactive T cells, and
thereby stimulate autoimmune disease, are currently under debate. In
this article, Chris Elson and colleagues suggest that cytokines associ
ated with T helper 1 (Th1) cells alter the processing of proteins and
that this effect can be counteracted by Th2-associated cytokines.