The enzyme IMPDH catalyzes the formation of xanthine monophosphate from inosine monophosphate and is the rate limiting enzyme in de novo guanine nucleotide biosynthesis. Because IMPDH is essential for providing the necessary precursors of DNA and RNA biosynthesis, cells with increased proliferation, such as cancer cells, generally exhibit increased IMPDH activity. In fact, studies have shown that IMPDH is highly upregulated in most hematological cancers and many solid tumors and inhibition of this enzyme represents a potentially important new approach to the treatment of cancer. Antibody Class – Mouse IgG1 Hybridoma Production: Full length IMPDH was purified from a Chinese hamster V79 cell variant which overproduces the enzyme. Purified IMPDH was used to immunize mice and hybridomas were produced and screened using standard methods. Hamster IMPDH differs from human IMPDH by only 4-6 amino acids (out of 514 total residues). References: Glesne, D., F. Collart and E. Huberman (1991) “Regulation of IMP Dehydrogenase gene expression by its end products, guanine nucleotides” Mol Cell Biol 11(11):5417 Hager, P., F. Collart, E. Huberman and B. Mitchell (1994) “Recombinant human inosine monophosphate dehydrogenase type I and type II proteins” Biochemical Pharmacol 49(9):1323

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