Abstract
Using immune electron microscopy (IEM), low-level cross-reactions could be demonstrated between the surface antigens of hepatitis B and woodchuck hepatitis. However, immune complex formation was greatly enhanced by pre-exposure of the antigens to 0.5% deoxycholate. Cross-reaction between the core antigens and e antigens of both viruses was also confirmed by IEM as well as radioimmunassay. It appears that the woodchuck sera used in this study may well contain an anti-immunoglobulin akin to rheumatoid factor.