A sensitive immunoassay for porcine interferon-alpha.
Two murine monoclonal antibodies (mAbs) directed against different epitopes on recombinant porcine interferon-alpha (IFN-alpha) were selected and used to construct a two-site ELISA. This ELISA, when performed in a one-step version, detected about 0.5 units ml-1 of IFN-alpha and showed similar sensitivity but better precision than a cytopathic effect inhibition bioassay. Estimates of IFN-alpha in tissue culture medium by the two assays correlated well. In contrast, one or several factors in porcine serum reduced the sensitivity of the ELISA. Measurements of IFN-alpha in porcine serum was, however, possible in a two-step version of the ELISA, with a sensitivity of about 1 unit IFN-alpha ml-1. Results of ELISA and bioassay agreed, except that the ELISA possibly produced false positive results in two out of a total of 91 sera negative in the bioassay. In addition, one of 23 sera positive in the bioassay was negative in the ELISA.
Diaz de Arce
H
H
Department of Veterinary Microbiology, Swedish University of Agricultural Sciences, Uppsala.
Artursson
K
K
L'Haridon
R
R
Perers
A
A
La Bonnardiere
C
C
Alm
G V
GV
D000818:Animals; D000911:Antibodies, Monoclonal / Q000096:biosynthesis / Q000276:immunology; D001681:Biological Assay; D003470:Culture Media; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods*; D000939:Epitopes / Q000276:immunology; D007370:Interferon Type I / Q000276:immunology; D016898:Interferon-alpha / Q000097:blood*; D051379:Mice; D011994:Recombinant Proteins; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013552:Swine
D000911:Antibodies, Monoclonal; D003470:Culture Media; D000939:Epitopes; D007370:Interferon Type I; D016898:Interferon-alpha; D011994:Recombinant Proteins