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Road 98 & Hutchison
CNPRC – UC Davis
Davis, CA 95616

530-752-8249

GIFN (Gamma-interferon)

In vitro assays for Interferon Gamma (IFN-g) response to tuberculin antigens represent a refinement of the lymphocyte stimulation assay. Within 24 hours of its collection, aliquots of heparinized whole blood are stimulated with control and TB antigens. After 24 hours incubation, the concentration of IFN-g in the supernatant plasma of each aliquot is determined by enzyme immunoassay. In experimental primate infection models, cell mediated immune responses are detectable in vitro 2 to 4 weeks after infection. IFN-g is a critical cytokine in the cell mediated immune response to tubeculin antigens, including the DTH response measured by the TST, and in the host immune response to infections with tuberculous mycobacteria. Primagam (Prionics, USA Inc, La Vista, NE) is a commercial version of this assay using bovine and avian purified protein derivatives (PPD) as antigens.

The minimum sample requirement is 3 ml of heparinized whole blood sent at room temperature to arrive within 24 hours of collection.