title: H9N2 influenza whole inactivated virus combined with polyethyleneimine strongly enhances mucosal and systemic immunity after intranasal immunization in mice.
abstract: Influenza whole inactivated virus (WIV) is more immunogenic and induces protective antibody responses compared with other formulations, like split virus or subunit vaccines, after intranasal mucosal delivery. Polyethyleneimine (PEI), an organic polycation, is widely used as a reagent for gene transfection and DNA vaccine delivery. Although PEI recently has demonstrated potent mucosal adjuvant activity for viral subunit glycoprotein antigens, its immune activity with H9N2 WIV is not well demonstrated. Here, mice were immunized intranasally with H9N2 WIV combined with PEI, and the levels of local respiratory tract and systemic immune responses were measured. Compared to H9N2 WIV alone, antigen-specific IgA levels in the local nasal cavity, trachea, and lung, as well as levels of IgG and its subtypes (IgG1 and IgG2a) in the serum, were strongly enhanced with the combination. Similarly, the activation and proliferation of splenocytes were markedly increased. In addition, PEI is superior as an H9N2 WIV delivery system due to its ability to greatly increase the viral adhesion to mucosal epithelial cells and to enhance the cellular uptake and endosomal escape of antigens in dendritic cells (DCs) and further significantly activate DCs to mature. Taken together, these results provided more insights that PEI has potential as an adjuvant for H9N2 particle antigen intranasal vaccination.
authors: Key Lab of Animal Physiology and Biochemistry of China's Department of Agriculture, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, People's Republic of China.
authors: Tao
authors: T
authors: Qin
authors: Key Lab of Animal Physiology and Biochemistry of China's Department of Agriculture, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, People's Republic of China.
authors: Yinyan
authors: Y
authors: Yin
authors: Key Lab of Animal Physiology and Biochemistry of China's Department of Agriculture, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, People's Republic of China.
authors: Lulu
authors: L
authors: Huang
authors: Key Lab of Animal Physiology and Biochemistry of China's Department of Agriculture, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, People's Republic of China.
authors: Qinghua
authors: Q
authors: Yu
authors: Key Lab of Animal Physiology and Biochemistry of China's Department of Agriculture, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, People's Republic of China zxbyq@njau.edu.cn.
authors: Qian
authors: Q
authors: Yang
mesh_terms: D000276:Adjuvants, Immunologic / Q000008:administration & dosage*; D000281:Administration, Intranasal; D000818:Animals; D000914:Antibodies, Viral / Q000032:analysis / Q000097:blood; D018928:Immunity, Mucosal; D007070:Immunoglobulin A / Q000032:analysis; D007074:Immunoglobulin G / Q000097:blood; D053127:Influenza A Virus, H9N2 Subtype / Q000276:immunology*; D007252:Influenza Vaccines / Q000008:administration & dosage* / Q000276:immunology*; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D011094:Polyethyleneimine / Q000008:administration & dosage*; D012137:Respiratory System / Q000276:immunology; D014611:Vaccination / Q000379:methods*; D015164:Vaccines, Inactivated / Q000008:administration & dosage / Q000276:immunology
chemical_list: D000276:Adjuvants, Immunologic; D000914:Antibodies, Viral; D007070:Immunoglobulin A; D007074:Immunoglobulin G; D007252:Influenza Vaccines; D015164:Vaccines, Inactivated; D011094:Polyethyleneimine