Serologically Cross-reactive Polypeptides in Vaccinia, Cowpox and Shope Fibroma Viruses

SUMMARY An immunoprecipitation method coupled with SDS-polyacrylamide gel electrophoresis (SDS-PAGE) was used to identify the serologically cross-reactive polypeptides in Orthopoxvirus (vaccinia and cowpox viruses) and Leporipoxvirus (Shope fibroma virus). Two early and four late polypeptides in cells infected with vaccinia or cowpox virus were specifically immunoprecipitated with antiserum against Shope fibroma virus. Two early and two late polypeptides in cells infected with Shope fibroma virus cross-reacted with both antiserum against vaccinia virus and antiserum against cowpox virus. The possibility of the common polypeptides being related to nucleoprotein antigen in these cross-reactive polypeptides was discussed.