Background: Human papillomavirus type 16 variants have been described and may have different biologic activities: this has implications for the design of HPV vaccines.
Objectives: The aim of this study was to see if the HPV16 variant E-G 131 can be detected in women with preinvasive disease and to consider the histological and immunological implications of such infection.
Design: A prospective observational cross-sectional study on a cohort of women with minor cervical cytological abnormalities was performed.
Methods: Samples were tested for HPV DNA by polymerase chain reaction and restriction enzyme digestion. Blood samples were tested for antibodies to HPV16 virus-like particles (VLP) and to determine class I HLA types. Women found to have abnormal colposcopy were treated by large-loop excision of the transformation zone on a see-and-treat basis.
Results: Two hundred forty-one women were included in the study. Infection with the variant was detected in 20. 9% of cases and was not associated with any specific HLA type. These cases were more likely to have high-grade CIN than those with wild-type HPV16 or no HPV16 (chi2 = 18.85, P < 0.001). There were significant differences in seropositivity to HPV16 virus-like particles between the three groups (chi2 = 32.43, P < 0.001).
Conclusions: The E-G 131 variant may have increased oncogenic potential by evading host immune responses, but its identification is only weakly predictive of high-grade disease in stepwise logistic regression. The lack of seropositivity to HPV16 VLP has implications for the design of prophylactic vaccines based on VLP to HPV16.
Copyright 1999 Academic Press.