RECOGNITION OF TROPHOBLASTS BY GAMMA-DELTA T-CELLS

The juxtaposition of maternal and fetal tissues in the hemochorial pla centa has led to speculation that maternal recognition of fetal Ags pr esent on trophoblasts might play an important role in reproductive bio logy. We report here for the first time such recognition of trophoblas ts by T lymphocyte hybridomas representative of certain cells present in the maternal decidua. Trophoblast recognition is TCR dependent and is mediated by members of the V gamma 1(+) subset of gamma delta T lym phocytes, a population that we previously have shown to be associated with heat shock protein-60 reactivity. Recognition occurred in experim ents in which trophoblast clones or freshly prepared trophoblasts were used and requires cell-cell interaction. Although the maternal-fetal immune relationship typically has been cast in terms of an allograft, the T cell recognition of trophoblasts as described herein is not MHC- restricted, inasmuch as freshly prepared trophoblasts from beta(2)-mic roglobulin-deficient mice were found to be stimulatory. Furthermore, t he trophoblast ligand that mediates this recognition is probably a con served mammalian molecule, because a human trophoblast cell line is al so stimulatory. Our findings suggest a novel form of T cell recognitio n, and may provide an enhanced understanding of the maternal-fetal imm une relationship.