PT - JOURNAL ARTICLE AU - J. P. PERKINS AU - G. HILLMAN AU - D. FISCHER AU - J. R. BERTINO TI - Antibody to Dihydrofolate Reductase from a Methotrexate-Resistant Subline of the L1210 Lymphoma DP - 1969 May 01 TA - Molecular Pharmacology PG - 213--218 VI - 5 IP - 3 4099 - http://molpharm.aspetjournals.org/content/5/3/213.short 4100 - http://molpharm.aspetjournals.org/content/5/3/213.full SO - Mol Pharmacol1969 May 01; 5 AB - An antiserum has been prepared against dihydrofolate reductase (EC 1.5.1.3) from mouse L1210 R tumor cells by injection of the purified enzyme into rabbits. The antiserum both precipitates and inactivates the enzyme; the antigen-antibody interaction fixes complement. The antibody inactivates dihydrofolate reductase from L5178Y, Ehrlich ascites carcinoma, and Sarcoma 180 murine tumors as well as that from the L1210 lymphoma. It partially inactivates enzyme from human bone marrow, but does not inactivate enzyme from Escherichia coli or from mouse, chicken, guinea pig, or rabbit liver. The cofactor NADPH, the substrates dihydrofolate and folate, and the inhibitor methotrexate protect the enzyme from inactivation by the antibody at low concentration.