The cDNAs of turkey and chicken interferon gamma (IFN-gamma) were cloned an
d the functional activity of turkey and chicken IFN-gamma was compared. The
coding region of turkey IFN-gamma gene encodes a predicted mature protein
of 145 amino acids with a molecular weight at 16.8 kDa. Compared with type
I IFN, the IFN-gamma between turkey and chicken also had the same size and
high degree of identity at the nucleotide (96.0%) and amino acid (96.4%) se
quence. Turkey IFN-gamma was cross-reactive with chicken cells. Both turkey
and chicken IFN-gamma could induce production of nitric oxide by turkey or
chicken macrophages. Turkey IFN-gamma also had similar degree of sensitivi
ty to heat and pH 2.0 as chicken IFN-gamma. The functional activity of both
turkey and chicken IFN-gamma could be neutralized by a monoclonal antibody
specific to chicken IFN-gamma to a similar extent. These results indicated
that IFN-gamma protein was cross-reactive between turkey and chicken. (C)
2001 Elsevier Science Inc. All rights reserved.