Laser scanning confocal examination and comparison of nidogen (entactin) with laminin in term human amniochorion.

Indirect immunofluorescence confocal microscopy was used to compare the distribution of nidogen (entactin) and laminin in term human amniochorion. Rabbit antiserum raised against recombinant mouse nidogen was immunoreactive with components of the amniotic epithelial basement membrane, chorion laeve basement membrane and maternally derived capillary basement membranes. Overall anti-nidogen immunoreactivity co-distributes with laminin except in the extracellular matrix of the maternally derived decidua, the embryonically derived trophoblast and the apical surfaces of the amniotic epithelia. These differences lead us to suggest that nidogen and laminin may be independently expressed and are not always complexed together. Original observations include dramatic parallel nidogen rich striations in the decidual layer, the fact that the trophoblastic basement membrane appears to extend inwards forming a boundary layer to degenerate chorionic villi and the finding that the recently discovered collagen type IV rich microtrabeculae of the fibroblast layer also contain nidogen and laminin.