© 1985 Oxford University Press
research-article |
Monoclonal antibodies to 1-aminopyrene-DNA
Cancer Center/Institute of Cancer Research, School of Public Health, Division of Environmental Science and Department of Pharmacology, Columbia University New York, NY 10027, USA
Monoclonal antibodies were obtained after fusion of mouse P3X63-AG.8.653 myeloma cells with spleen cells isolated from BALB/cCr mice immunized with denatured DNA modified by 1-nitrosopyrene reduced with sodium ascorbate (AP-d-DNA) and complexed electrostatically to methylated bovine serum albumin. Ten stable hybridoma lines have been isolated and characterized by enzyme-linked immunosorbent assay (ELISA). They all recognize 1-aminopyrene (1-AP)modified DNA, but not free 1-nitropyrene or 1-aminopyrene. Antibody 11H2 is the most specific for AP-DNA showing no cross-reactivity with unmodified native DNA. It also recognizes 8-nitro-1-AP and 6-nitro-1-AP modified DNA. There was some low cross-reactivity with DNA modified by a benzo[a]pyrene diol epoxide and N-acetoxy-N-2-acetylaminofluorene. Competitive ELISA with antibody 11H2 reliably detected AP-DNA adducts formed when 1-nitropyrene was incubated with Salmonella typhimurium TA1538. By immunological methods, AP-DNA adducts were shown to be unstable to heat denaturation. This suggests that specific monoclonal antibodies to carcinogen-DNA adducts will be useful not only for detecting and quantitating carcinogen-DNA damage but also for probing adduct stability.