Lyme disease, Borrelia burgdorferi-caused infection, if not recognized and appropriately treated by antibiotics, may lead to chronic complications, thus stressing the need for protective vaccine development. The immune protection is mediated by phagocytic cells and by Borrelia-specific complement-activating antibodies, associated with the Th1 immune response. Surface antigen OspC is involved in Borrelia spreading through the host body. Previously we reported that recombinant histidine tagged (His-tag) OspC (rOspC) could be attached onto liposome surfaces by metallochelation. Here we report that levels of OspC-specific antibodies vary substantially depending upon whether rOspC possesses an N' or C' terminal His-tag. This is the case in mice immunized: (a) with rOspC proteoliposomes containing adjuvants MPLA or non-pyrogenic MDP analogue MT06; (b) with free rOspC and Montanide PET GEL A; (c) with free rOspC and alum; or (d) with adjuvant-free rOspC. Stronger responses are noted with all N'-terminal His-tag rOspC formulations. OspC-specific Th1-type antibodies predominate post-immunization with rOspC proteoliposomes formulated with MPLA or MT06 adjuvants. Further analyses confirmed that the structural features of soluble N' and C' terminal His-tag rOspC and respective rOspC proteoliposomes are similar including their thermal stabilities at physiological temperatures. On the other hand, a change in the position of the rOspC His-tag from N' to C' terminal appears to affect substantially the immunogenicity of rOspC arguably due to steric hindrance of OspC epitopes by the C' terminal His-tag itself and not due to differences in overall conformations induced by changes in the His-tag position in rOspC variants.

• MeSH
• Adjuvants, Immunologic * MeSH
• Antigens, Bacterial administration & dosage   chemistry   immunology   MeSH
• Borrelia burgdorferi immunology   MeSH
• Enzyme-Linked Immunosorbent Assay MeSH
• Immunization MeSH
• Lyme Disease immunology   MeSH
• Models, Animal MeSH
• Mice MeSH
• Bacterial Outer Membrane Proteins administration & dosage   chemistry   immunology   MeSH
• Proteolipids MeSH
• Antibodies, Bacterial immunology   MeSH
• Recombinant Fusion Proteins administration & dosage   chemistry   immunology   isolation & purification   MeSH
• Protein Structure, Secondary MeSH
• Antibody Specificity immunology   MeSH
• Protein Stability MeSH
• Antibody Formation immunology   MeSH
• Animals MeSH
• Check Tag
• Mice MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Names of Substances
• Adjuvants, Immunologic * MeSH
• Antigens, Bacterial MeSH
• OspC protein MeSH Browser
• Bacterial Outer Membrane Proteins MeSH
• Proteolipids MeSH
• proteoliposomes MeSH Browser
• Antibodies, Bacterial MeSH
• Recombinant Fusion Proteins MeSH