title: An evaluation under code of new techniques for the detection of cytomegalovirus antibodies: sensitivity of assays and importance of immune complexes.
abstract: Given the morbidity and occasional mortality associated with cytomegalovirus infection and the requirement for good seroepidemiologic tools, assays of high sensitivity and reliability are needed for detection of cytomegalovirus-specific antibody. We report the successful application of two sensitive techniques, antibody-dependent cellular cytotoxicity (ADCC) and the enzyme-linked immunosorbent assay (ELISA) for the measurement of these antibodies and document their favorable comparison with conventional techniques, complement fixation (CF) and indirect hemagglutination (IHA). A coded panel of 48 sera from patients with culture-proven cytomegalovirus infection and disease controls was tested in a controlled fashion by all four procedures. Among 18 CF-positive sera, specific antibody was detected by IHA, ADCC and ELISA in dilutions 100 to 1000-fold higher than measurable by the CF test. Ten of 15 sera, seronegative by CF, were nevertheless found to be cytomegalovirus antibody-positive when assessed by the other procedures. Further, the importance of circulating antigen-antibody complexes upon ADCC test results was documented. Eight sera, known to be antibody-positive by other techniques but with an unexpectedly low (or negligible) capacity to induced ADCC, were found to be immune complex-positive by the Raji cell assay. Ultracentrifugation, useful in precipitating antigen-antibody complexes, enhanced ADCC activity in five of six sera known to be complex-positive. It is suggested that the simultaneous application of multiple antibody detection systems, particularly the newly-developed ones (ADCC, ELISA) will provide both earlier diagnostic information as well as a more comprehensive understanding of the human host's immune response to infection with cytomegalovirus.
mesh_terms: D000914:Antibodies, Viral / Q000032:analysis*; D000920:Antibody-Dependent Cell Cytotoxicity; D000936:Antigen-Antibody Complex; D003168:Complement Fixation Tests; D003587:Cytomegalovirus / Q000276:immunology*; D004797:Enzyme-Linked Immunosorbent Assay; D005069:Evaluation Studies as Topic; D006386:Hemagglutination Tests; D006801:Humans; D007118:Immunoassay / Q000379:methods*
chemical_list: D000914:Antibodies, Viral; D000936:Antigen-Antibody Complex