[Immunochemical approach to the identification of specific markers of the corneal epithelium in Rana temporaria].

Biochemical and immunochemical studies of water soluble proteins in the corneal epithelium (CE) of adult frogs were carried out. Up to 30-40 protein fractions were found in the CE extracts using the methods of isoelectrofocusing and electrophoresis with SDS. The major part of the CE proteins is in the acid zone (pH 4.2-6.2) and is presented by three peptide fractions in the molecular weight range of 40-50 kD. The CE peptide spectrum is most close to that of epidermis and differs markedly from that of lens fibers. Up to 20 water-soluble antigens were revealed by rabbit antisera against the total extract, among them 10 antigens are immunologically similar with the blood serum proteins. Out of 10 tissue antigens, 6 are interorganic. Only two corneal antigens were not found in epidermis. One of them was found only in CE, retina and lens epithelium. Another antigen is present in considerable quantities only in liver, heart and lung. The synthesis of most tissue specific antigens and antigens immunologically similar with alpha- and beta-crystallins of R. temporaria was shown in CE by immunoautoradiography. The antigenic composition proved to be similar in CE, epidermis and lens epithelium.