The CTLA-4 gene is expressed in placental fibroblasts

In order to elucidate the mechanisms that ensure survival of the allogeneic fetus, we are investigating the expression pattern of genes that are invol ved in peripheral self-tolerance in tissues at the maternal-fetal interface . Cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) is a negative regula tor of T cell activation and may modulate peripheral self-tolerance. Previo usly, we reported the preferential transmission of maternally-inherited sho rter alleles at a 3'-UTR microsatellite locus to liveborn children, but ran dom transmission of paternally-inherited alleles, suggesting that CTLA-4 ma y be involved in the maintenance of tolerance at the maternal-fetal interfa ce. In this report, we demonstrate that CTLA-4 mRNA and protein are indeed expressed in fetal tissues at the maternal-fetal interface throughout gesta tion.