title: Anti-D prozone and membrane sulfhydryl modification.
abstract: An IgG anti-D prozone is produced by progressive inactivation of the D antigen following red cell exposure to increasing concentrations of thimerosal and phenol present as antibody excess is achieved. Partial inactivation of the D antigen by routinely added thimerosal, an organic mercurial, and phenol is associated with an unstable D antigen-antibody complex resulting in an increased rate of dissociation of anti-D and with a decreased reactivity of the cell-bound anti-D in the antiglobulin reaction. Complete D inactivation occurs with concentrations in excess of 0.43 microM thimerosal. If attributable to inactivation of a surface-exposed sulfhydryl group, it suggests that less than 5 percent of these are involved in D-antigen activity. The data do not exclude the possibility that D inactivation may result from alteration of sulfhydryl groups other than those exposed at the surface.
mesh_terms: D000915:Antibody Affinity / Q000187:drug effects; D001666:Binding Sites, Antibody / Q000187:drug effects; D003298:Coombs Test; D004910:Erythrocyte Membrane / Q000187:drug effects*; D006384:Hemagglutination / Q000187:drug effects*; D006801:Humans; D007136:Immunoglobulins / Q000276:immunology / Q000502:physiology*; D007700:Kinetics; D019800:Phenol; D010636:Phenols / Q000494:pharmacology; D012204:Rh-Hr Blood-Group System / Q000276:immunology*; D018029:Rho(D) Immune Globulin; D013438:Sulfhydryl Compounds / Q000378:metabolism*; D013849:Thimerosal / Q000494:pharmacology
chemical_list: D007136:Immunoglobulins; D010636:Phenols; D012204:Rh-Hr Blood-Group System; D018029:Rho(D) Immune Globulin; D013438:Sulfhydryl Compounds; D013849:Thimerosal; D019800:Phenol