title: Development and immunogenicity of recombinant GapA(+) Mycoplasma gallisepticum vaccine strain ts-11 expressing infectious bronchitis virus-S1 glycoprotein and chicken interleukin-6.
abstract: Mycoplasma gallisepticum (MG) is a major pathogen of poultry that causes chronic respiratory disease in chickens and infectious sinusitis in turkeys. A live attenuated vaccine, ts-11, has been used for the control of MG in several countries. The efficacy of this vaccine is highly dose dependent and the flock antibody response is weak. To improve the functionality of the vaccine and investigate its potential as a delivery vector for foreign antigens and immunomodulatory proteins, we developed a derivative of ts-11 expressing infectious bronchitis virus-S1 glycoprotein (IBV-S1) and releasing chicken interleukin-6 into the extracellular milieu (MG ts-11 C3 (+CS)) using a transposon-based delivery vector. Following administration of MG ts-11 C3 (+CS) to chickens by eye-drop, an antibody response to MG and IBV-S1, as determined by the rapid serum agglutination test (RSA) and Western blotting, respectively, could be detected. Birds inoculated with the recombinant vaccine had significantly enhanced weight gain and were partially protected against damage by pathogenic IBV. These results indicate that the ChIL-6 released by MG ts-11 C3 (+CS) may have had a non-specific effect on growth rate. They also suggest that ts-11 is a promising vaccine vector, capable of delivering heterologous protective antigens, and may also provide non-specific benefits when engineered to express immunomodulatory proteins. With some improvements in the expression system, it could be used to induce a targeted immune response against specific mucosal pathogens, and co-expression of several antigens would allow development of a novel multivalent vaccine.
authors.affiliation: Asia Pacific Centre for Animal Health, School of Veterinary Science, The University of Melbourne, Parkville, Victoria 3010, Australia.
authors.forename: Pollob K
authors.initials: PK
authors.lastname: Shil
authors.forename: Anna
authors.initials: A
authors.lastname: Kanci
authors.forename: Glenn F
authors.initials: GF
authors.lastname: Browning
authors.forename: Philip F
authors.initials: PF
authors.lastname: Markham
mesh_terms: D018829:Adhesins, Bacterial / Q000235:genetics / Q000276:immunology*; D000372:Agglutination Tests; D000818:Animals; D000907:Antibodies, Bacterial / Q000097:blood; D000914:Antibodies, Viral / Q000097:blood; D001428:Bacterial Vaccines / Q000235:genetics / Q000276:immunology*; D015153:Blotting, Western; D001835:Body Weight; D002645:Chickens; D018352:Coronavirus Infections / Q000276:immunology / Q000473:pathology / Q000517:prevention & control / Q000662:veterinary; D015850:Interleukin-6 / Q000235:genetics / Q000276:immunology*; D008562:Membrane Glycoproteins / Q000235:genetics / Q000276:immunology*; D045686:Mycoplasma gallisepticum / Q000235:genetics / Q000276:immunology*; D011201:Poultry Diseases / Q000276:immunology / Q000473:pathology / Q000517:prevention & control; D064370:Spike Glycoprotein, Coronavirus; D014613:Vaccines, Attenuated / Q000235:genetics / Q000276:immunology; D014614:Vaccines, Synthetic / Q000235:genetics / Q000276:immunology; D014759:Viral Envelope Proteins / Q000235:genetics / Q000276:immunology*; D014765:Viral Vaccines / Q000235:genetics / Q000276:immunology*
chemical_list: D018829:Adhesins, Bacterial; D000907:Antibodies, Bacterial; D000914:Antibodies, Viral; D001428:Bacterial Vaccines; C117938:GapA cytadhesin; D015850:Interleukin-6; D008562:Membrane Glycoproteins; D064370:Spike Glycoprotein, Coronavirus; D014613:Vaccines, Attenuated; D014614:Vaccines, Synthetic; D014759:Viral Envelope Proteins; D014765:Viral Vaccines