The Interferon-α Genes from Three Chicken Lines and Its Effects on H9N2 Influenza Viruses

Abstract

The interferon-alpha genes from three chicken lines were cloned by a direct PCR technique, and the effects of recombinant protein expressed in a prokaryotic system on highly pathogenic H9N2 influenza viruses were investigated. The cloned ChIFN-alpha gene encoded a protein of 193 amino acids with a signal sequence of 31 amino acids and mature peptides of 162 amino acids. Comparison of ChIFN-alpha sequences, detected six amino acids substitutions at positions 50, 58, 65, 81, 181, and 183. Homology analysis indicated that ChIFN-alpha genes could be subdivided into two lineages, SH-ChIFN-alpha and WJ-ChIFN-alpha. In addition, both SH-ChIFN-alpha and WJ-ChIFN-alpha were expressed with the N-terminal 6 consecutive histidine residues in a high-level prokaryotic expression system. Recombinant chicken interferon-alpha (rChIFN-alpha) protein has anti-VSV activity of more than 1 x 10(8) U/mg. Moreover, High concentration (10,000U) of rSH-ChIFN-alpha resulted in over 40% inhibition of the H9N2 virus infection in chicken embryos (Ovo), and 100% inhibition from one day-old to five day-old chickens (Vivo). The results suggested that rChIFN-alpha is a potential agent against many Chicken viral strains.

Avian Interferons and Their Antiviral Effectors

“…Several recent studies have mapped the expression dynamics of chicken type I IFNs triggered by different stimuli ( 60 – 63 ). Collectively, type I IFNs (especially IFN-α) are potent antiviral agents and can ameliorate viral infections including Marek’s disease virus (MDV), infectious bursal disease virus (IBDV), infectious bronchitis virus (IBV), and HPAIV in different avian species ( 43 – 47 ). These antiviral properties of type I IFNs are identified not only in vitro but also in ovo and in vivo ( 43 , 47 ).…”

Low-Pathogenicity Influenza Virus

“…All strains of chickens tested, including those in the People’s Republic of China, have proved to be sensitive to the action of rChIFN-α ( 14 ). Genetically engineered production of rChIFN-α ( 15 ), treatment with it optimized for dose and duration, and its long half-life in water may make it economically feasible to convert many birds in a flock to super-sentinel status.…”

A study on cloning, expressing and investigating biological activity of recombinant chicken interferon produced from yeast Pichia pastoris

“…ChIFNs đã được chứng minh có hoạt tính kháng virus mạnh. Các protein này có khả năng kìm hãm sự nhân lên của các virus như Rous Sarcoma Virus (RSV) [13], Marek's Disease Virus (MDV) [7], Newcastle Disease Virus (NDV) [10], Avian Influenza Virus (AIV) [16,20], Vesicular Stomatitis Virus (VSV), Semliki Forest Virus (SFV) [15], và Infectious Bronchitis Virus (IBV) [12].…”