title: Epitope specific immunity elicited by a synthetic streptococcal antigen without carrier or adjuvant.
abstract: A polypeptide fragment of type 24 streptococcal M protein (pep M24) has been shown to raise protective anti-streptococcal antibodies in rabbits and humans when administered with adjuvants. More recently, such protective antibodies were shown to be evoked by a synthesized 35-residue sub-peptide fragment (S-CB7 synthetic cyanogen bromide fragment 7) of pep M24. We now show that the weak pep M24 immunogen induces high titers of long lasting antibodies when associated with murabutide, a synthetic derivative of MDP (NAcMur-L-Ala-D-Gln-n-butyl-ester) which is currently undergoing clinical trials. We demonstrate also that the polymerized synthetic S-CB7 administered without adjuvant or carrier evokes a strong epitope specific, protective immune response in mice primed with the parent pep M24. A booster dose of polymerized S-CB7 induced antibodies directed specifically against the S-CB7 structure whereas a booster dose of pep M24 evoked antibodies recognizing additional determinants of the whole pep M24 molecule.
mesh_terms: D000119:Acetylmuramyl-Alanyl-Isoglutamine / Q000031:analogs & derivatives / Q000276:immunology; D000818:Animals; D000918:Antibody Specificity; D000942:Antigens, Bacterial; D001425:Bacterial Outer Membrane Proteins; D001426:Bacterial Proteins / Q000276:immunology*; D002352:Carrier Proteins; D000939:Epitopes / Q000276:immunology*; D005260:Female; D006801:Humans; D051379:Mice; D010446:Peptide Fragments / Q000138:chemical synthesis / Q000276:immunology*; D010587:Phagocytosis
chemical_list: D000942:Antigens, Bacterial; D001425:Bacterial Outer Membrane Proteins; D001426:Bacterial Proteins; D002352:Carrier Proteins; D000939:Epitopes; D010446:Peptide Fragments; C014689:streptococcal M protein; D000119:Acetylmuramyl-Alanyl-Isoglutamine; C033575:murabutide