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.
Department of Veterinary Microbiology, Swedish University of Agricultural Sciences, Uppsala.
H
H
Diaz de Arce
K
K
Artursson
R
R
L'Haridon
A
A
Perers
C
C
La Bonnardiere
G V
GV
Alm
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