title: Immunogenicity of low-pH treated whole viral influenza vaccine.
abstract: Low pH treatment of influenza virus hemagglutinin (HA) exposes its relatively conserved stalk domain, suggesting a potential immunogen with capability to induce broader immune responses. Here, we describe characterization, immunogenicity, antigenicity, and protective immunity induced by low pH treated inactivated whole viral vaccine in comparison with the untreated vaccine. The acidic pH treated viral vaccine showed high susceptibility to proteolytic cleavage and low hemagglutination activity indicating conformational changes. Immunization of mice with low pH treated viral vaccine induced lower levels of homologous or heterologous virus-specific binding and neutralizing antibodies compared to the untreated vaccine. Also, low pH treated influenza viral antigen showed lower antigenicity compared to the untreated influenza viral antigen. Lower efficacy of cross-protection against heterosubtypic virus was observed in the low-pH treated vaccine group. The results provide evidence that there is a correlation between protective efficacy and the stability of vaccines.
authors: Department of Microbiology and Immunology, Emory University School of Medicine, Atlanta, GA 30322, USA.
authors: Fu-Shi
authors: FS
authors: Quan
authors: Zhu-Nan
authors: ZN
authors: Li
authors: Min-Chul
authors: MC
authors: Kim
authors: Dan
authors: D
authors: Yang
authors: Richard W
authors: RW
authors: Compans
authors: David A
authors: DA
authors: Steinhauer
authors: Sang-Moo
authors: SM
authors: Kang
mesh_terms: D000818:Animals; D000914:Antibodies, Viral / Q000097:blood*; D000918:Antibody Specificity; D002460:Cell Line; D003429:Cross Reactions; D004285:Dogs; D005260:Female; D006388:Hemagglutinins / Q000737:chemistry / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D007252:Influenza Vaccines / Q000276:immunology*; D051379:Mice; D008807:Mice, Inbred BALB C; D008958:Models, Molecular; D009976:Orthomyxoviridae Infections / Q000517:prevention & control*; D011487:Protein Conformation; D015164:Vaccines, Inactivated
chemical_list: D000914:Antibodies, Viral; D006388:Hemagglutinins; D007252:Influenza Vaccines; D015164:Vaccines, Inactivated