Immunological Methods

IMMUNOLOGICAL METHODS

  • Immunological methods include
    • Tube precipitin test
    • Haemagglutination test (HAT)
    • Complement fixation test (CFT)
    • Agar gel immuno diffusion test (AGID)
    • Dry disc immuno diffusion test
    • Enzyme linked immuno sorbent assay (ELISA)

Agar Gel Immuno Diffusion Test (AGID)

  • Based on a simple double diffusion method (Ouchterlony, 1948). Species specific antiserum (antibody) and unidentified meat extract (antigen) are allowed to diffuse towards one another in an agar gel slab. If the antigen and antibody are homologous a precipitin band is formed along the line where the two meet.

Enzyme Linked Immuno Sorbent Assay (ELISA)

  • The technique involves the application of species specific antibodies to the proteins (antigen) coated on the plastic surface of micro-titre plate.
  • The recognition of antigen results in the formation of antigen-antibody complex, which are detected by either enzyme linked immunoglobulin or protein A (antibody detector) producing visible colour reaction with added substrate.
  • The colour intensity is measured objectively at a specific wave length in a micro ELISA reader as absorbance value.

Recent techniques in meat species identification include

  • Production of monoclonal antibodies and application of ELISA.
  • Use of DNA probes and application of DNA hybridization technique.
  • Use of Polymerase Chain Reaction (PCR) in species identification.
Last modified: Saturday, 24 December 2011, 5:21 AM