IMMUNOELECTRON MICROSCOPY OF SKIN BASEMENT-MEMBRANE ZONE ANTIGENS - APREEMBEDDING METHOD USING 1-NM IMMUNOGOLD WITH SILVER ENHANCEMENT

There is no single immunoelectron microscopical method for invariably effective localization of both intracellular and extracellular antigen s. We describe a simple and practicable immunogold technique that can be used to localize various skin basement membrane zone antigens at th e ultrastructural level. Small pieces of skin were incubated with prim ary antibodies recognizing epitopes on a range of basement membrane zo ne-related antigens (two different lamina lucida-associated antigens, laminin, type VII collagen, fibrillin and keratin 14). This was follow ed by incubation with 1-nm colloidal gold-conjugated secondary antibod y and subsequent silver intensification. The specimens were then proce ssed for transmission electron microscopy. Precise immunolocalization with good ultrastructural preservation was achieved for all basement m embrane zone antibodies tested. The results of basal cell keratin immu nostaining showed that this microscopic approach could also be applied to some extent in the characterization of intracellular antigens. Thi s immunoelectron microscopy technique provides a useful approach to th e study of macromolecules at the basement membrane zone.