Rapid laboratory diagnosis of human cytomegalovirus infection using monoclonal antibody

The monoclonal antibody E. 13, recognized an early nonstructure antigen (68 KD) of human cytomegalovirus (HCMV), was used for early detection of HCMV in cell cultures. The virus antigen could be detected by the indirect immunofluorescence staining (IF) technique 6 hours after inoculation of HCMV AD169 and NTUH871233 strains into human embryonic lung fibroblast (HELF) cells growing in shell vials prepared by low speed centrifugation (700xg) at 25 degrees C for 1 hour. The intensity of fluorescence reached a peak 14 hours after virus inoculation and remained at the same level for 72 hours. The feasibility of application of this technique for rapid detection of HCMV in the clinical virology laboratory was tried. A total of 201 urine specimens requesting HCMV isolation were inoculated into HELF cells using the shell vial culture method. The virus growth in the shell vial cultures was detected by the indirect IF technique with the monoclonal antibody E.13 at 16 to 18 hours postinoculation. The results obtained were compared with those of the conventional tube culture method. The sensitivity and specificity of the test vs the conventional tube culture method for detection of HCMV in clinical specimens were 93.06% and 99.22%, respectively. The average time of virus isolation by the conventional culture method was 10.9 days, whereas final results with the shell vial culture method were obtained in only one day. The above results indicate that detection of HCMV early antigen in infected cells with monoclonal antibody E.13 is a sensitive and reliable method for rapid diagnosis of HCMV infections.