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

530-752-8249

Mycobacterium Tuberculosis (TB)

Infected animals with active TB may show no overt signs of disease for weeks or months, during which time they can transmit infection to other colony animals. Animals with latent TB are not infectious and may appear healthy for years, but eventual reactivation of latent TB can result in secondary transmission and outbreaks of disease in established colonies. Reactivation of latent infections that were not detected using traditional screening methods during primary quarantine is emerging as an important factor in the epidemiology of TB in nonhuman primates. 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 tuberculin 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 in vitro assay for Interferon Gamma (IFN-g) response to tuberculin antigens. It represents a refinement of the lymphocyte stimulation assay. This assay uses bovine and avian purified protein derivatives (PPD) as antigens. We have modified the commercial assay to include additional antigens, incubation conditions, and cytokine levels. 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.

Antibody assays are currently under development and validation. Please contact us for specific information.