Serological response to HPV 16 in cervical dysplasia and neoplasia: correlation of antibodies to E6 with cervical cancer.

Sera from patients with cervical cancer, cervical intraepithelial neoplasia (CIN) and non-genital cancers, and from healthy individuals, were investigated for antibodies to human papilloma virus (HPV) early proteins E4, E6 and E7 and the major capsid protein LI by Western blot analysis of recombinant HPV proteins. There was a significantly higher prevalence of sera with antibodies to E6 in cervical cancer patients than in healthy individuals or in CIN or non-genital-cancer patients. Antibodies to E7 were detected in 25% of cervical-cancer patients, which is significantly higher than in HPV-associated cervical lesions or in control populations, but not significantly different from the incidence in patients with non-genital cancers. Antibodies to LI were found more frequently in CIN, while antibodies to E4 had a similar prevalence in cervical-cancer, cervical-dysplasia and non-genital-cancer groups, with 24% in the controls. The inability to detect antibodies to E6 and E7 in the majority of cervical-cancer patients limits the application of this methodology to the monitoring of HPV infection and the development of cervical cancer. However, the latter approach may be useful in combination with other assay systems which allow detection of different, including conformational, epitopes of HPV E6 and/or E7 recombinant proteins.