Lectin histochemistry in the developing oto-maxillo-facial primordia of the mouse embryo.

The binding sites of several lectins (Con-A, SBA, WGA, PNA, RCA-I, UEA-I, DBA) were studied in the different tissues involved in mouse visceral cephalogenesis. As compared to various other lectins which have only a weak affinity for precartilaginous rudiments, PNA preceded by neuraminidase treatment shows a very strong fixation in the precartilaginous blastemata and their immediate environment. PNA receptors exist also on the enamel epithelium and mesenchymal sac. RCA affinity for blood vessels has also enabled detailed observations on the vascularization of the palatal shelves, particularly in area 3. Various other localizations have been described and correlated with other histochemical data.