PPIB and hepatitis A virus infection: Though our prior work demonstrated that the presence of endotoxin does not increase the immunogenicity of human hepatitis B VLPs in mice [43], and we have not seen any evidence for endotoxin increasing the immunogenicity of WHc VLPs in rabbits (unpublished), we evaluated whether the reduction of endotoxin in the purified VLP148 would reduce the immunogenicity in rabbits.