Quantitative comparison of direct and cold-target competition assay in monocyte- and complement-mediated lysis of sensitized erythrocytes.
Differences in the number of the antigenic determinants of A1 and B erythrocytes were exploited to study the influence of the sensitization on antibody-dependent monocyte- and complement-mediated cytotoxicity. Lysis was compared in direct and cold target competition assays. The findings were: (1) Monocyte mediated lysis of both targets was similar; A1 erythrocytes, however, showed stronger competitive inhibition than B cells; (2) the competitive inhibition was influenced by the antiserum concentration in a range where the direct lysis was not; (3) in the presence of optimal concentrations of hyperimmune antisera and complement, A1 erythrocytes were lysed, while B erythrocytes were not; and (4) A1 cells exposed to suboptimal concentrations of complement consumed complement, while B cells did not. It was concluded that the cold target competition assay is more sensitive than the direct cytotoxicity test to detect differences in the sensitization of erythrocytes.
National Institute of Oncology, Budapest, Hungary.
T
T
Bakács
K
K
Tótpál
G
G
Ringwald
E
E
Klein
D000906:Antibodies; D000911:Antibodies, Monoclonal; D003165:Complement System Proteins / Q000276:immunology*; D003602:Cytotoxicity, Immunologic; D004912:Erythrocytes / Q000276:immunology*; D006461:Hemolysis; D006801:Humans; D007700:Kinetics; D009000:Monocytes / Q000276:immunology*
D000906:Antibodies; D000911:Antibodies, Monoclonal; D003165:Complement System Proteins