Mycobacterium bovisBCG Vaccination Augments Interleukin-8 mRNA Expression and Protein Production in Guinea Pig Alveolar Macrophages Infected withMycobacterium tuberculosis

Abstract

Despite the existence of the Mycobacterium bovis BCG vaccine, the death toll from tuberculosis (TB) exceeds 3 million individuals annually, making TB the leading infectious killer of adults worldwide (13). BCG is the only vaccine available at this time for the control of TB. Due to variations in the ability of BCG to protect uniformly against adult TB, new candidate vaccines are being tested in murine and guinea pig models (5, 47). The search for a better TB vaccine would be greatly facilitated by a clearer understanding of the mechanisms involved in vaccine-induced resistance in the guinea pig model of tuberculosis (27,28,29).There are several indications that chemokines participate in the host defense of the lung against bacterial pathogens during which the effective response is characterized by recruitment and activation of inflammatory cells, such as granuloma formation during infection with Mycobacterium tuberculosis (8,19,21,45,55). Alveolar macrophages are the first cell type to encounter M. tuberculosis in a pulmonary infection, and these resident macrophages are known to produce cytokines and chemokines as a result of stimulation by M. tuberculosis (42,49,55). This production first causes an influx of proinflammatory neutrophils, which is then followed by an infiltration of monocytes and T lymphocytes.

Production and Characterization of Guinea Pig Recombinant Gamma Interferon and Its Effect on Macrophage Activation

“…9). This is consistent with our earlier findings that macrophages from BCG-vaccinated animals had enhanced IL-1␤, RANTES, IL-8, and TNF-␣ mRNA levels compared to cells from nonvaccinated animals following stimulation with PMA and LPS or infection with virulent or attenuated M. tuberculosis (20,28,31). Interestingly, increased MHC class II expression, production of H 2 O 2 , and an increased ability to control intracellular survival of M. tuberculosis even when rgpIFN-␥ was added after infection were observed only in macrophages from BCG-vaccinated animals, which further confirms that these macrophages are more activated or more susceptible to activation than cells from naive guinea pigs.…”

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

“…Real-time primers for gpTNF-␣, IL-12 p40, and hypoxanthine phosphoribosyltransferase (HPRT) were designed using Primer Express software and are described in Table 1. Quantitative real-time PCR was performed using SYBR Green PCR Supermix and the ABI Prism 7700 sequence detector from Applied Biosystems according to our previously published protocol (38). Fold induction levels of mRNA were obtained by analyzing cycle threshold (Ct) levels normalized to HPRT Ct values.…”

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

“…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. Recently, a highly quantitative mRNA detection system, real-time PCR, has been introduced to the field of TB investigation [1,2,8,10].…”

“…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]. In this study, new RT-PCR primer sets were developed for the detection of mRNA of several cytokines and other effector molecules in guinea pigs.…”