Use of monoclonal antibody probes against rat hepatic cytochromes P-450c and P-450d to detect immunochemically related isozymes in liver microsomes from different species.
Nine distinct monoclonal antibodies raised against purified rat liver cytochrome P-450c react with six different epitopes on the antigen, and one of these epitopes is shared by cytochrome P-450d. None of these monoclonal antibodies recognize seven other purified rat liver isozymes (cytochromes P-450a, b, and e-i) or other proteins in the cytochrome P-450 region of "Western blots" of liver microsomes. Each of the monoclonal antibodies was used to probe "Western blots" of liver microsomes from untreated, or 3-methylcholanthrene-, or isosafrole-treated animals to determine if laboratory animals other than rats possess isozymes immunochemically related to cytochromes P-450c and P-450d. Two protein-staining bands immunorelated to cytochromes P-450c and P-450d were observed in all animals treated with 3-methylcholanthrene (rabbit, hamster, guinea pig, and C57BL/6J mouse) except the DBA/2J mouse, where no polypeptide immunorelated to cytochrome P-450c was detected. The conservation of the number of rat cytochrome P-450c epitopes among these species varied from as few as two (guinea pig) to as many as five epitopes (C57BL/6J mouse and rabbit). The relative mobility in sodium dodecyl sulfate-gels of polypeptides immunorelated to cytochromes P-450c and P-450d was similar in all species examined except the guinea pig, where the polypeptide related to cytochrome P-450c had a smaller Mr than cytochrome P-450d. With the use of both monoclonal and polyclonal antibodies, we were able to establish that purified rabbit cytochromes P-450 LM4 and P-450 LM6 are immunorelated to rat cytochromes P-450d and P-450c, respectively.
D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology*; D006224:Cricetinae; D003429:Cross Reactions; D003577:Cytochrome P-450 Enzyme System / Q000276:immunology*; D004591:Electrophoresis, Polyacrylamide Gel; D000939:Epitopes / Q000032:analysis; D006168:Guinea Pigs; D005779:Immunodiffusion; D007527:Isoenzymes / Q000276:immunology*; D008297:Male; D051379:Mice; D008862:Microsomes, Liver / Q000201:enzymology*; D011817:Rabbits; D012451:Safrole / Q000494:pharmacology; D013045:Species Specificity
D000911:Antibodies, Monoclonal; D000939:Epitopes; D007527:Isoenzymes; D003577:Cytochrome P-450 Enzyme System; D012451:Safrole; C015959:isosafrole