PAPILLOMAVIRUS L1 CAPSIDS AGGLUTINATE MOUSE ERYTHROCYTES THROUGH A PROTEINACEOUS RECEPTOR

Virus-like particles (VLPs) composed of L1 derived from bovine papillo mavirus type 1 (BPV-1), several human papillomavirus types, or cottont ail rabbit papillomavirus (CRPV) agglutinated mouse but not human or r at erythrocytes. Treatment of mouse erythrocytes with trypsin prevente d hemagglutination (HA) by BPV-1. Sera from rabbits immunized with nat ive CRPV VLPs, which protect against experimental CRPV infection, exhi bited high titers of antibodies that inhibited CRPV VLP HA activity, w hile sera from rabbits immunized with denatured CRPV VLPs or native BP V VLPs, which do not protect against CRPV infection, were not inhibito ry. Testing for HA inhibition is a rapid and simple method for examini ng the serological relatedness of papillomaviruses and measuring prote ctive antibody titers after VLP vaccination.