A Hepatitis B Surface Antigen Mutant That Lacks the Antigenic Loop Region Can Self-Assemble and Interact with the Large Hepatitis Delta Antigen

A novel hepatitis B virus surface antigen mutant harboring a deletion of most of the major antigenic loop region was competent for self-assembly and secretion. Although the mutant protein was competent for interaction with and incorporation of free large hepatitis delta antigen, it was partially defective in hepatitis delta virus RNP incorporation.