ENHANCEMENT OF THE IMMUNOGENICITY OF A SYNTHETIC PEPTIDE BEARING A VP3 EPITOPE OF HEPATITIS-A VIRUS

The immune responses elicited in mice by different forms of the VP3(11 0-121) B-epitope of the hepatitis A virus (HAV) were studied. Differen t forms of incorporation in liposomes were tested, encapsulation, rath er than surface exposure, being the best antigenic preparation, Three larger peptides of fire VP3 epitope, two of them containing a hepatiti s B virus T-epitope, and a third containing a putative T-epitope of HA V (VP3(102-121)) were assayed, While this latter T-epitope induced an enhancement of the response against the VP3 B-epitope, the artificiall y coupled T-epitopes failed to induce a significant increase, The admi nistration of two multiple antigenic peptide (MAP) constructs, the fir st containing the VP3(110-121) and VP1(11-25) HAV sequences and the se cond only the VP1(11-25) sequence, also suggested the presence of a T- epitope, since the response against the VP1 peptide was increased in t he first construct, (C) 1998 Federation of European Biochemical Societ ies.