Fingerprints of anergic T cells

Peripheral T cell tolerance may result from activation-induced cell death [ 1], anergy [1], and/or immune response modulation by regulatory T cells [2] , In mice that express a transgenic receptor specific for peptide 111-119 o f influenza hemagglutinin presented by Ed class II MHC molecules as well as hemagglutinin under central of the immunoglobulin-le promoter, we have fou nd that anergic T cells [3] can also have immunoregulatory function and sec rete IL-10 [4], In order to obtain information on molecular mechanisms invo lved in anergy and immunoregulation, we have compared expression levels of 1176 genes in anergic, naive, and recently activated CD4(+) T cells of the same specificity by gene array analysis. The results provide a plausible ex planation for the anergic phenotype in terms of proliferation, provide new information on the surface phenotype of in vivo-generated anergic CD4(+) T cells, and yield clues with regard to new candidate genes that may be respo nsible for the restricted cytokine production of in vivo-anergized CD4+ T c ells. The molecular fingerprints of such T cells should enable the tracking of this small population in the normal organism and the study of their rol e in immunoregulation.