title: Salmonella flagellin is a potent carrier-adjuvant for peptide conjugate to induce peptide-specific antibody response in mice.
abstract: As an agonist to innate immune system, Salmonella flagellin has been proven to be a potent adjuvant either admixed or genetically fused with antigens and applied to a variety of vaccines against infectious diseases. However, relatively little is known about its carrier-adjuvant effect for conjugate vaccine. Conjugation is an effective approach often used to make haptens such as some peptides and polysaccharides immunogenic and in some cases used to make poor immunogens more immunogenic. In the current study, Salmonella flagellin was tested for its carrier-adjuvant effect in a peptide conjugation. The recombinant Salmonella flagellin (rFliC) purified from Escherichia coli was firstly modified by maleimide groups, then coupled with a synthetic peptide (EXP153:CDNNLVSGP) that is a B-cell epitope derived from Plasmodium falciparum exported protein-1 to generate the conjugate of EXP153-rFliC. Bioactivity assay showed that both chemical modification and conjugation did not apparently impair the TLR5-ligand activity of rFliC. EXP153-rFliC was used to immunize BALB/c mice via subcutaneous route, and the sera obtained from immunized mice were examined by ELISA and IFA. While no detectable antibody responses were induced by the peptide admixed with rFliC, the robust peptide-specific antibody responses were observed in mice immunized with the peptide conjugated to rFliC in the absence of any additional adjuvant. The immune sera induced by the conjugate recognized the native protein of malaria parasite. The data obtained from this study demonstrate the carrier-adjuvant activity of Salmonella flagellin in peptide conjugate immunization and indicate its promising application for conjugate vaccine research and development.
authors.affiliation: Department of Rheumatology and Immunology, Shanghai Changzheng Hospital, Second Military Medical University, Shanghai 200003, China. Electronic address: fqian_cn@hotmail.com.
authors.forename: Feng
authors.initials: F
authors.lastname: Qian
authors.affiliation: Department of Rheumatology and Immunology, Shanghai Changzheng Hospital, Second Military Medical University, Shanghai 200003, China.
authors.forename: Aihua
authors.initials: A
authors.lastname: Guo
authors.affiliation: Department of Rheumatology and Immunology, Shanghai Changzheng Hospital, Second Military Medical University, Shanghai 200003, China.
authors.forename: Mengmeng
authors.initials: M
authors.lastname: Li
authors.affiliation: Department of Rheumatology and Immunology, Shanghai Changzheng Hospital, Second Military Medical University, Shanghai 200003, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Liu
authors.affiliation: Jiangsu Key Lab of Zoonosis/Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou 225009, China.
authors.forename: Zhiming
authors.initials: Z
authors.lastname: Pan
authors.affiliation: Department of Rheumatology and Immunology, Shanghai Changzheng Hospital, Second Military Medical University, Shanghai 200003, China.
authors.forename: Lei
authors.initials: L
authors.lastname: Jiang
authors.affiliation: Department of Rheumatology and Immunology, Shanghai Changzheng Hospital, Second Military Medical University, Shanghai 200003, China.
authors.forename: Xin
authors.initials: X
authors.lastname: Wu
authors.affiliation: Department of Rheumatology and Immunology, Shanghai Changzheng Hospital, Second Military Medical University, Shanghai 200003, China. Electronic address: xuhuji@smmu.edu.cn.
authors.forename: Huji
authors.initials: H
authors.lastname: Xu
mesh_terms: D000276:Adjuvants, Immunologic; D000818:Animals; D000913:Antibodies, Protozoan / Q000097:blood; D000953:Antigens, Protozoan / Q000276:immunology*; D004797:Enzyme-Linked Immunosorbent Assay; D018985:Epitopes, B-Lymphocyte / Q000276:immunology; D004926:Escherichia coli / Q000235:genetics; D005408:Flagellin / Q000008:administration & dosage / Q000276:immunology*; D007106:Immune Sera; D017780:Malaria Vaccines / Q000276:immunology*; D051379:Mice; D008807:Mice, Inbred BALB C; D010446:Peptide Fragments / Q000276:immunology*; D010963:Plasmodium falciparum / Q000276:immunology*; D011993:Recombinant Fusion Proteins / Q000276:immunology; D012475:Salmonella; D018074:Vaccines, Conjugate / Q000008:administration & dosage / Q000276:immunology*
chemical_list: D000276:Adjuvants, Immunologic; D000913:Antibodies, Protozoan; D000953:Antigens, Protozoan; D018985:Epitopes, B-Lymphocyte; D007106:Immune Sera; D017780:Malaria Vaccines; D010446:Peptide Fragments; C063362:QF116 antigen, Plasmodium falciparum; D011993:Recombinant Fusion Proteins; D018074:Vaccines, Conjugate; D005408:Flagellin
keywords: Adjuvant; Carrier; Conjugation; Peptide; Salmonella flagellin