GENOMIC AND FUNCTIONAL ANALYSIS OF THE MUCOSAL IMMUNE RESPONSE AND ITS ROLE IN PROTECTION AGAINST RESPIRATORY PATHOGENS IN POULTRY
Location: Exotic and Emerging Avian Viral Diseases Research Unit
Title: Cross reactive cytotoxic T lymphocytes from MHC-defined birds against homologous and heterologous avian influenza subtypes
Submitted to: International Symposium on Animal Genomics for Animal Health
Publication Type: Abstract Only
Publication Acceptance Date: April 2, 2010
Publication Date: May 31, 2010
Citation: Kapczynski, D.R., Liljebjelke, K.A., Kulkarni, G., Hunt, H.D., Jiang, H., Petkov, D. 2010. Cross reactive cytotoxic T lymphocytes from MHC-defined birds against homologous and heterologous avian influenza subtypes [abstract]. International Symposium on Animal Genomics for Animal Health, May 31-June 2, 2010, Paris, France. p. 18.
Numerous reports have implicated a role of the major-histocompatibility complex (MHC) in genetic resistance of chickens to bacterial infection and viral diseases. However, little is known about the role of MHC in generating protective immunity following avian influenza (AI) infection. Because vaccines for use in commercial poultry against AI are mainly inactivated and delivered parenterally, our knowledge of protective immunity of poultry against AI is largely based on the induction of serum-neutralizing antibodies produced against a specific hemagglutinin (HA) protein subtype. In contrast, cytotoxic T-lymphocyte (CTL) responses against influenza A viruses have been shown to cross react with different subtypes of influenza isolates, and have been reported as critical for clearance of virus from infected animals. In these studies, MHC-defined (B2/B2) chickens were infected with a recent H9N2 AI isolate, and antibody and CTL cross reactivity against homologous (H9N2) and heterosubtypic (H6N2 and H5N9) AI viruses were determined ex vivo. Results indicate antibodies produced against H9N2 AI displayed better cross reactivity to the H6N2 isolate than the H5N9 isolate. Additionally, splenic lymphocytes from H9N2-infected chickens displayed cross reactive lysis of B2/B2 lung target cells infected with any of the isolates tested here. Removal of the CD8+ population, but not CD4+ T cells, abrogated specific lysis of target cells. Taken together, these studies provide insight into the cross reactive nature of avian CTL’s against homologous and heterosubtypic AI viruses.