HEAT-SHOCK PROTEIN EXPRESSION IN HUMAN PLACENTA AND UMBILICAL-CORD

We examined the level of heat shock proteins (HSPs) present in umbilic al cord vessels and placenta following delivery. A 10 cm segment of fr esh umbilical cord was obtained immediately after delivery and a place ntal biopsy was obtained following the third stage of labor. Apgar sco res, cord pHs, and pertinent histories were recorded. Tissues were pre pared and analyzed for HSP mRNA by in situ hybridization, Western blot , and immunohistochemistry. Sixteen patients were studied, HSP72 mRNA was selectively expressed in the vascular smooth muscle in all cord ar teries and veins. This correlated with marked expression of HSP72 prot ein in the vascular media. Both HSP72/73 mRNA and protein expression w ere noted diffusely in the placenta. HSP27 protein was highly expresse d in umbilical cords with lower levels present in placentas. There wer e no correlations between method of delivery, gestational age, Apgar s core, cord pH, or fetal outcome to the magnitude or distribution of th e HSP response. This is the first demonstration of HSP expression in t he human maternal-fetal circulation.