conformational epitopes or that a subset of the women with HPV18 or HPV31 infection had been previously infected with HPV16 and remained seropositive.
The development of virus-like particle ELISAs for other HPV types should provide information on the serological relationship between the virions of different HPV types. By using particles from several HPV types, it should be possible to develop an ELISA that recognizes the majority of high-risk HPV infections. The clinical utility of this type of assay remains to be determined, especially since a substantial minority of women with HPV16 infection are negative in the assay. However, these assays should help to determine the extent of antivirion humoral immunity induced during natural genital HPV infections and if there are serological subtypes of HPV16 or other genital HPVs. This information will be important when the components for a multivalent virus-like particle vaccine to prevent genital HPV infection are considered. In addition, the ELISA will be useful to evaluate seroconversion in virus-like particle vaccine trials in animals and, perhaps ultimately, in humans.
Genital human papillomavirus (HPV) infection is a common sexually transmitted disease that at the present time is not effectively controlled or treated. Many infections are inapparent and transient. However, some HPV infections result in persistent lesions that in some cases undergo carcinogenic progression. A subset of genital HPVs, designated high-risk types, are preferentially associated with high-grade dysplasias and carcinomas. About 90% of cervical cancers contain high-risk HPV DNA, most often HPV16. Development of a subunit vaccine against high-risk genital HPVs is a desirable and, it appears, an increasingly feasible long-term goal. The viral E6 and E7 oncoproteins are selectively maintained and expressed in progressed HPV tumors and could potentially be targets for therapeutic vaccines. The L1 major virion structural proteins have recently been shown to self-assemble into virus-like particles when expressed in insect cells. These particles might serve as the basis for a prophylactic vaccine to prevent genital HPV infection.
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2. Brinton, L. A. (1992) in The Epidemiology of Human Papillomavirus and Cervical Cancer, eds. Munoz, N., Bosch, F. X., Shah, K. V. & Meheus, A. (Int. Agency of Res, on Cancer, Lyon, France), pp. 3–23.