Immunohistochemical study of. GAMMA.-glutamyl transpeptidase with monoclonal antibodies. I Preparation and characteristics of monoclonal antibodies to. GAMMA.-glutamyl transpeptidase

Monoclonal antibodies of the IgG₁ subclass were prepared against rat kidney γ-glutamyl transpeptidase by the hybridoma technique. Eight hybrid clones produced antibodies against the enzyme. Finally two stable clones which produce specific antibodies were obtained. The antibodies specifically recognized a heavy subunit (Mr=51, 000) of the enzyme. Immunohistochemical examination revealed that the reaction was localized in the brush border as well as along the basolateral membrane of the proximal convolution of rat kidney and also in the epididymis and the pancreas of rats. Human kidney showed positive reaction, whereas no reaction was recognized in the kidneys of other species, such as mice, guinea pigs and rabbits.