Monoclonal antibodies to the H+-K+ ATPase of gastric mucosa selectively stain the non-pigmented cells of the rabbit ciliary body epithelium.

Monoclonal antibodies developed against the transport enzyme H+-K+ ATPase of gastric mucosa selectively bind to the nonpigmented cell layer in both the pars plana and pars plicata of the rabbit ciliary body epithelium. The most specific of these antibodies (HK 12.18) reacts with the nonpigmented cells but with no other cell type in ciliary body, retina or iris. Antibody reactivity is evinced by a distinct particulate staining which is greater on the surfaces of the nonpigmented cells than within the cytoplasm and seems most intense on the apical membrane between the pigmented and nonpigmented cell layers. This pattern of staining was present in 2-3-day-old pups and in young adults, in both pigmented and albino animals. Similar staining was not observed in control sections treated with preimmune serum, nonspecific mouse monoclonal antibody, or HK 12.18 preabsorbed to gastric microsomes. In addition to staining intact ciliary body, the antibody HK 12.18 can be shown to react with a population of cells lacking pigment granules in suspensions of dissociated ciliary body epithelium. This antibody may therefore be useful as a marker for the identification of nonpigmented cells in tissue culture.