Differential Expression of Gamma Interferon mRNA Induced by Attenuated and VirulentMycobacterium tuberculosisin Guinea Pig Cells afterMycobacterium bovisBCG Vaccination

Abstract

To determine whether

Effect ofMycobacterium bovisBCG Vaccinationon Mycobacterium-Specific Cellular Proliferation and TumorNecrosis Factor Alpha Production from Distinct Guinea PigLeukocytePopulations

“…In either case, TNF-␣ induction in primary macrophages appears to be highly dependent on the experimental protocol and the origin of cells and bacterial strains under investigation. Our findings that TNF-␣ production positively correlates with the virulence of the mycobacterial strain employed demonstrates that, in guinea pigs, virulent mycobacteria may not effect a broad immunological "silence" implicated from previous studies in our laboratory (15,16,19). Instead, it is conceivable that M. tuberculosis H37Rv elevates host phagocyte TNF-␣ levels to facilitate its own survival by interfering with the production of IL-12 (20) and possibly increasing its availability to iron (10).…”

“…Previous work in this laboratory demonstrated that BCG vaccination in guinea pigs enhances both chemokine (RAN-TES and IL-8) and cytokine (IL-1-␤ and IFN-␥) mRNA responses from various cell cultures (i.e., alveolar macrophages, adherence-purified peritoneal exudate cells, and whole splenocytes [SPC]) (15,16,19). This vaccination effect was observed in response to different multiplicities of infection (MOIs) with various attenuated and virulent mycobacterial strains.…”

Recombinant Guinea Pig Tumor Necrosis Factor Alpha Stimulates the Expression of Interleukin-12 and the Inhibition ofMycobacterium tuberculosisGrowth in Macrophages

“…The isolation of resident macrophages was based on established protocols (26,36). Euthanasia was carried out by intramuscular injection with 100 mg of sodium pentobarbital (Sleepaway; Fort Dodge Laboratories, Inc., Fort Dodge, Iowa)/kg of body weight.…”

Newly Designed Primer Sets Available for Evaluating Various Cytokines and iNOS mRNA Expression in Guinea Pig Lung Tissues by RT-PCR

“…Antibodies against guinea pig cytokines are not available for setting up guinea pig cytokine ELISA. So far, guinea pig IFN-γ, TNF-α, IL-1β, IL-2, IL-10, IL-12p40, GM-CSF, TGF-β and iNOS mRNA have been sequenced and their accession numbers are readily available [7,15,20], but RT-PCR has not been available for examining the expression of these mRNAs. Thus, our study is useful because our RT-PCR detects immunological changes in M. tuberculosis-infected guinea pig tissues at the mRNA level over time.…”

“…Bioassays for IFN-γ and TNF-α and northern blot analysis with limited cDNA probes have been used to examine the development of guinea pig TB [6,7,9,12]. Although real-time RT-PCR has been used recently to examine gene expression quantitatively [1,2,8,10], conventional RT-PCR is a more convenient method and uses cheaper reagents and devices [16-19, 22, 23].…”