ABSTRACT
Nine everlapping peptides covering the entire sequence of early protein E7 of human papillomavirus type 18 (HPV-18) were synthesized and tested as antigens with pools of selected human sera in ELISA. Peptides denoted 18/E7-2, 18/E7-3, and 18/E7-5 (amino acid positions 11-33, 21-40, and 41-60, respectively) were reactive with pooled sera originating from HPV-18 DNA-positive cervical cancer patients but not with sera from HPV-16 DNA-positive cervical cancer patients or from condyloma acuminata patients. This suggested that the epitopes contained in these peptides were HPV-18 type-specific, relative to HPV types 16, 11, and 6. On the other hand, 18/E7-1 (aa 1-23) and 18/E7-6 (aa 51-70) peptides were cross-reactive. The prevalence of antibodies reactive with 18/E7-2, 18/E7-3, and 18/E7-5 peptides in cervical carcinoma patients was very low. Thus, the utilization of these peptides for monitoring HPV-18 infection seems to be rather limited.
