title: Construction of Recombinant HVT Expressing PmpD, and Immunological Evaluation against Chlamydia psittaci and Marek's Disease Virus.
abstract: Chlamydia psittaci (C. psittaci) is an obligate intracellular zoonotic pathogen that can be transmitted to humans from birds. No efficacious commercial vaccine is available for clearing chlamydial infection due to lack of potential vaccine candidates and effective delivery vehicles. Herpesvirus of turkeys (HVT) is an efficacious commercially available vaccine against Marek's Disease virus (MDV). In this study, a recombinant HVT-delivered vaccine against C. psittaci and Marek's disease was developed and examined. The 5'-terminus of pmpD gene (pmpD-N) encoding the N-terminal fragment of polymorphic membrane protein D of C. psittaci was inserted into a nonessential region of HVT genome using reverse genetics based on an infectious bacterial artificial chromosome (BAC) clone of HVT. The recombinant virus (rHVT-pmpD-N) was recovered from primary chicken embryo fibroblast (CEF) cells by transfection of modified HVT BAC DNA containing the pmpD-N gene. The rHVT-pmpD-N construct was confirmed to express PmpD-N by immunoblot and immunofluorescence. The rHVT-pmpD-N was stable during 20 passages in vitro. The growth kinetics of rHVT-pmpD-N was comparable to that of parental HVT in vitro and in vivo. One-day-old SPF chickens inoculated subcutaneously with rHVT-pmpD-N displayed increased PmpD-specific antibody levels and a vigorous PmpD-specific lymphocyte proliferation response using HVT vector or CEF cells as control. Furthermore, the percentage of CD4+ cells was significantly elevated in rHVT-pmpD-N-immunized birds as compared to the parental HVT. All chickens vaccinated with rHVT-pmpD-N or parental HVT were protected completely against challenge with a very virulent strain of Marek's Disease virus (MDV) RB-1B. Post challenge with C. psittaci CB7 strain, a significant decrease in respiratory distress, lesions and Chlamydia load was found in the rHVT-pmpD-N-vaccinated group compared to the parental HVT. In conclusion, our study suggests that the rHVT-pmpD-N live vaccine may be viable as a candidate dual vaccine that provides protection against both very virulent MDV and C. psittaci.
authors.affiliation: Key Lab of Animal Epidemiology and Zoonosis of Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University,Beijing 100193, China; Institute of Animal Husbandry and Veterinary Medicine, Beijing Academy of Agricultural and Forestry Sciences, Beijing 100097, China.
authors.forename: Shanshan
authors.initials: S
authors.lastname: Liu
authors.affiliation: Institute of Animal Husbandry and Veterinary Medicine, Beijing Academy of Agricultural and Forestry Sciences, Beijing 100097, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Sun
authors.affiliation: Key Lab of Animal Epidemiology and Zoonosis of Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University,Beijing 100193, China.
authors.forename: Jun
authors.initials: J
authors.lastname: Chu
authors.affiliation: Institute of Animal Husbandry and Veterinary Medicine, Beijing Academy of Agricultural and Forestry Sciences, Beijing 100097, China.
authors.forename: Xiufen
authors.initials: X
authors.lastname: Huang
authors.affiliation: Key Lab of Animal Epidemiology and Zoonosis of Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University,Beijing 100193, China.
authors.forename: Zongxue
authors.initials: Z
authors.lastname: Wu
authors.affiliation: Institute of Animal Husbandry and Veterinary Medicine, Beijing Academy of Agricultural and Forestry Sciences, Beijing 100097, China.
authors.forename: Minxin
authors.initials: M
authors.lastname: Yan
authors.affiliation: Key Lab of Animal Epidemiology and Zoonosis of Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University,Beijing 100193, China.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Zhang
authors.affiliation: Key Lab of Animal Epidemiology and Zoonosis of Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University,Beijing 100193, China.
authors.forename: Peng
authors.initials: P
authors.lastname: Zhao
authors.affiliation: National Center for Emerging and Zoonotic Infectious Diseases, CDC, Atlanta, Georgia, 30333, United States of America.
authors.forename: Joseph U
authors.initials: JU
authors.lastname: Igietseme
authors.affiliation: National Center for Emerging and Zoonotic Infectious Diseases, CDC, Atlanta, Georgia, 30333, United States of America.
authors.forename: Carolyn M
authors.initials: CM
authors.lastname: Black
authors.affiliation: Key Lab of Animal Epidemiology and Zoonosis of Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University,Beijing 100193, China.
authors.forename: Cheng
authors.initials: C
authors.lastname: He
authors.affiliation: Institute of Animal Husbandry and Veterinary Medicine, Beijing Academy of Agricultural and Forestry Sciences, Beijing 100097, China.
authors.forename: Yongqing
authors.initials: Y
authors.lastname: Li
mesh_terms: D000818:Animals; D001426:Bacterial Proteins / Q000737:chemistry*; D001428:Bacterial Vaccines / Q000235:genetics / Q000276:immunology*; D049109:Cell Proliferation; D002645:Chickens; D002691:Chlamydophila psittaci; D022202:Chromosomes, Artificial, Bacterial; D005822:Genetic Vectors; D000882:Haplorhini; D008381:Herpesvirus 2, Gallid; D056724:Immunity, Humoral; D008380:Marek Disease / Q000517:prevention & control; D008565:Membrane Proteins / Q000737:chemistry*; D008856:Microscopy, Fluorescence; D011201:Poultry Diseases / Q000382:microbiology / Q000517:prevention & control* / Q000821:virology; D009956:Psittacosis / Q000517:prevention & control; D011994:Recombinant Proteins / Q000737:chemistry; D014765:Viral Vaccines / Q000235:genetics / Q000276:immunology*
chemical_list: D001426:Bacterial Proteins; D001428:Bacterial Vaccines; D008565:Membrane Proteins; D011994:Recombinant Proteins; D014765:Viral Vaccines