SEQUENCE CONSERVATION WITHIN THE MAJOR CAPSID PROTEIN OF HUMAN PAPILLOMAVIRUS (HPV) TYPE-18 AND FORMATION OF HPV-18 VIRUS-LIKE PARTICLES INSACCHAROMYCES-CEREVISIAE

The major capsid protein L1 of human papillomaviruses (HPVs) has been identified as a promising candidate antigen for a prophylactic HPV vac cine. Since amino acid sequence heterogeneity has been demonstrated fo r the L1 genes within individual HPV types, nucleotide sequences for L 1 were determined from six HPV-18 clinical isolates and the cervical c arcinoma cell line SW756 and compared to the published HPV-18 prototyp e sequence. The sequences were almost identical between the clinical i solates and SW756 but differed markedly from the published prototype s equence. Resequencing the prototype HPV-18 revealed that these differe nces were due to sequencing artifacts of the prototype HPV-18 sequence archived in GenBank. Thus, the HPV-18 L1 genes seem to display a very high level of sequence conservation. The HPV-18 L1 gene derived from SW756 was expressed in Saccharomyces cerevisiae and self-assembly of t he L1 protein into viruslike particles was demonstrated.