Monoclonal antibodies to cytomegalovirus: rapid identification of clinical isolates and preliminary use in diagnosis of cytomegalovirus pneumonia.

Two monoclonal antibodies which react specifically with cells infected by cytomegalovirus (CMV) are described. One antibody, 6-E3, reacts with a 72,000-dalton protein that appears early in infection and remains localized in the cell nucleus. The other antibody, 6-C5, reacts with an 80,000-dalton protein that appears late in infection and remains localized in cytoplasmic inclusion bodies. Both monoclonal antibodies react with conventional laboratory strains of CMV and can be used in immunofluorescence assays to identify clinical isolates of CMV in culture. Preliminary tests on lung tissues from patients with CMV pneumonia show that only antibody 6-C5 detects CMV infection in primary clinical specimens. A comparison of culture, histological, and immunological methods demonstrates that the monoclonal antibodies possess sufficient specificity and sensitivity to warrant their continued development as immunodiagnostic tools for the detection of CMV infection in both tissue culture and tissues obtained directly from patients.