Detection of HPV-16 in cell lines and cervical lavage specimens by a polymerase chain reaction-enzyme immunoassay assay.

A gene amplification method that combines the polymerase chain reaction with detection of amplified DNA in a solution hybridization/enzyme immunoassay (PCR-EIA) was developed for HPV-16 DNA. Samples were amplified with primers for the E7-E1 region of HPV-16. Amplified DNA products were identified and quantitated by hybridization in solution with a biotinylated RNA probe. Labeled DNA/RNA hybrids were measured semiquantitatively in an enzyme immunoassay using solid phase anti-biotin antibody and liquid phase B-d-galactosidase labeled monoclonal antibody against DNA-RNA hybrids. Enzyme bound to the solid phase was quantitated with a fluorogenic substrate. The assay was linear over 2 log10 dilutions of SiHa cells and the detection limit was three copies of HPV-16 genome. The sensitivity of PCR-EIA for detection of PCR amplified products compared favorably with slot and Southern blots using a 32P-labeled RNA probe. The assay was used to assess HPV-16 infection of uterine cervix in women attending a clinic for sexually transmitted diseases. Twenty-one of the 81 specimens (25.9%), obtained by cervicovaginal lavage, were positive for HPV-16 by PCR-EIA. The assay provides a convenient means to objectively measure HPV DNA amplified with PCR.