Development of a novel antigen capture-ELISA using IgY against porcine interleukin-6 and its application

J Vet Sci. 2004 Dec;5(4):337-43.

Abstract

Interleukin-6 (IL-6) is introduced as a marker of disease. At present, a variety of method may be used to quantify expression of this protein. Antigen capture-ELISA is a sensitive and accurate quantification method previously used with ovine, rat, and human IL-6 proteins. However, it has never been reported to quantify porcine IL-6 protein using capture ELISA. In this study, we generated and characterized a set of IgY and mono-specific polyclonal antibodies to recombinant porcine IL-6 (rpIL-6), and combining these with a sensitive and specific capture-ELISA for a diagnostic purpose. cDNA encoding the mature protein coding region of porcine IL-6 was cloned and expressed with pQE-30UA expression vector. rpIL-6 was then expressed and purified by using Ni-NTA resin. Protein mass of 24 kDa was found with SDS-PAGE and the identity of the protein was confirmed by Western-blot. Production of polyclonal antibodies against rpIL-6 was performed using the purified rpIL-6 in mice and hens. An antigen capture-ELISA was developed with the antibodies after their extraction. To compare the IL-6 level in the different sanitary state of farms, pig sera were randomly collected and concentration of IL-6 in the sera was measured with the antigen capture-ELISA. The capture-ELISA with the optimal concentration of antibodies, in this study, was able to detect about 10 ng/ml of rpIL-6. IL-6 levels determined with the capture-ELISA in pig sera showed positive correlation with the sanitary states of the farms. These results suggested that the developed antigen capture-ELISA could be a good tool for the screening of microbial infection in pig farms.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Biomarkers / blood
  • Blotting, Western / veterinary
  • Chickens
  • Cloning, Molecular
  • DNA, Complementary / genetics
  • DNA, Complementary / isolation & purification
  • Electrophoresis, Polyacrylamide Gel / veterinary
  • Enzyme-Linked Immunosorbent Assay / methods
  • Enzyme-Linked Immunosorbent Assay / veterinary*
  • Female
  • Immunoglobulins / blood*
  • Interleukin-6 / immunology*
  • Mice
  • Mice, Inbred ICR
  • Recombinant Proteins / immunology
  • Swine / immunology*

Substances

  • Biomarkers
  • DNA, Complementary
  • IgY
  • Immunoglobulins
  • Interleukin-6
  • Recombinant Proteins