Lysine conjugate of acrylonitrile as antigenic sites in hemoglobin adducts.
For biomonitoring environmental exposure to acrylonitrile (AN), a monoclonal antibody (mAb) A2D1, was developed to recognize specifically the hemoglobin (Hb) adduct, Hb-AN, but not Hb itself. This appears to be the first example that a small molecule-like AN may introduce new antigenicity into hemoglobin, which already exhibits multiple antigenic determinants. This report addresses the localization of the newly formed antigenic sites in human Hb-AN. As antigenic probes, the AN conjugates of 10 amino acids, six dipeptides, and four tripeptides were prepared as monitored by 1H NMR, and their antigenicity was evaluated by competitive inhibition immunoassay. A Lys-epsilonNH-AN was found essential to inhibiting activity. The potent peptide-AN inhibitors, containing a sequence of His and Lys, showed IC50 at the micromolar concentration, thus implicating human Hbalpha-89,90 and Hbbeta-143,144 in the distal heme pocket region as the new antigenic sites.
Department of Chemistry, University of Louisville, Louisville, KY 40292, USA. jlwong01@louisville.edu
J L
JL
Wong
D Z
DZ
Liu
Y T
YT
Zheng
D000181:Acrylonitrile / Q000737:chemistry / Q000276:immunology* / Q000633:toxicity; D000818:Animals; D000911:Antibodies, Monoclonal / Q000737:chemistry; D000941:Antigens / Q000737:chemistry / Q000276:immunology; D001667:Binding, Competitive / Q000187:drug effects; D004784:Environmental Monitoring; D004797:Enzyme-Linked Immunosorbent Assay; D006454:Hemoglobins / Q000737:chemistry / Q000276:immunology* / Q000378:metabolism; D006801:Humans; D007118:Immunoassay; D008239:Lysine / Q000737:chemistry*; D051379:Mice; D010455:Peptides / Q000737:chemistry / Q000276:immunology / Q000494:pharmacology
D000911:Antibodies, Monoclonal; D000941:Antigens; D006454:Hemoglobins; D010455:Peptides; D008239:Lysine; D000181:Acrylonitrile