Lectin histochemistry of the human amnio-chorionic membrane complex.

The presence and distribution of glycoconjugates within the human amnion, chorion, and decidual tissues was examined histochemically following incubation with HRP-labelled lectins. Glycoconjugates within the cytoplasm of cells as well as the extracellular matrix of the maternal decidual layer and fetal chorio-amniotic membranes reacted selectively with OFA, LTA, WGA, PSA, UEA-I, GSAI-B4, RCA-I, LFA, VVA, PHA-E, and GSA-II. Conjugated lectins specific for L-fucose-stained components of amnion, chorion laeve, and decidua while other lectins bound glycoconjugates within decidua and at the junction between maternal decidua and fetal chorionic tissue. These observations suggest that the amnio-chorionic membrane complex may include several histochemically distinct and specialized subpopulations of glycoconjugates distributed within cells and the extracellular matrix. Although specific functions for these glycoconjugates have not been elucidated, they may mediate transport of amniotic fluid and/or facilitate maternal recognition of the developing fetus.