Constraints in antigen presentation severely restrict T cell recognition of the allogeneic fetus.

ABSTRACT: How the fetus escapes rejection by the maternal immune system remains one of the major unsolved questions in transplantation immunology. Using a system to visualize both CD4+ and CD8+ T cell responses during pregnancy in mice, we find that maternal T cells become aware of the fetal allograft exclusively through "indirect" antigen presentation, meaning that T cell engagement requires the uptake and processing of fetal/placental antigen by maternal APCs. This reliance on a relatively minor allorecognition pathway removes a major threat to fetal survival, since it avoids engaging the large number of T cells that typically drive acute transplant rejection through their ability to directly interact with foreign MHC molecules. Furthermore, CD8+ T cells that indirectly recognize fetal/placental a

SUBMITTER: Erlebacher A 

PROVIDER: S-EPMC1849983 | biostudies-literature | 2007 May

REPOSITORIES: biostudies-literature