DETECTION OF HUMAN PAPILLOMAVIRUS TYPE-16 IN MICROTITRE PLATE BASED IMMUNO-ENZYMATIC ASSAYS - USE TO DETERMINE E5 GENE-EXPRESSION IN CERVICAL CARCINOMAS

Background: E5-based nested polymerase chain reaction (PCR) assays and a PCR-enzyme immunoassay (EIA) to detect human papillomavirus type 16 (HPV-16) DNA have been developed. These assays were designed to detec t small amounts of HPV-16 DNA for epidemiological studies of subclinic al infection. Objectives: The E5 gene of HPV-16 may be lost in some ce ll lines derived from cervical carcinomas. The aim of this study was t o determine if, and how frequently, E5 gene loss occurs in biopsy samp les from patients with cervical lesions. Study design: Sixteen HPV-16 (E7) DNA positive and five HPV-16 DNA negative cervical lesions (ninet een cervical carcinomas, two cervical intraepithelial neoplasias) were investigated by E5 nested PCR and EIA. Results: Overall, 15 of the 16 (93.75%) HPV-16 E7 positive samples were positive for HPV-16 E5 DNA: 14 of 16 (87.5%) were positive by E5 PCR and 15 of 16 (93.75%) were po sitive by E5 PCR, nested PCR and by PCR-EIA. One of 14 HPV-1B (E7) DNA positive cervical carcinomas was negative for E5 DNA in all three ass ays. Conclusion: Loss of the HPV-16 E5 open reading frame (ORF) is a r are event in HPV-16 positive cervical carcinomas and was detected in j ust one of 14 (7.1%) cases.