The aims of the current investigation were to determine whether functional polymorphisms in the tumor necrosis factor-alpha (TNF-alpha) gene at position -308; in the transforming growth factor-beta 1 (TGF-beta1) gene at positions -509, +869 (codon 10), and +915 (codon 25); in the interleukin-10 (IL-10) gene at position -1,082, -819 and -592; and in the intron 1 of the interferon-gamma (IFN-gamma) gene at position +874 are associated with silicosis and PTB.
In response to live M. tuberculosis and CFA, significantly increased levels of IL-6, IL-8 and TGF-beta and decreased IFN-gamma, IL-12p40 and IL-10 were seen in PTB patients compared to NHS.
Our findings suggested that IL -10 (-1082 G/A) and IL -12B 3'UTR (Taq I) (A/C) gene polymorphisms were not associated either with susceptibility or resistance to pulmonary tuberculosis in the south Indian population.
We have also uncovered a high incidence of antigen-specific anergy to purified protein derivative among patients with active pulmonary TB and have correlated this with an expansion of immunosuppressive IL-10 producing T cells and other impaired T cell responses to mycobacterial antigens.
Here are reported data on the evaluation of the frequency of the functional polymorphisms at genes coding for TNF-alpha (-308G-->A) and IL-10 (-1082G-->A), analysed by ARMS-PCR, in a group of Sicilian patients affected by chronic lung tuberculosis (TBC) compared to that from a group of healthy individuals living in the same region.
Here, polymorphisms in the natural resistance-associated macrophage protein 1 (NRAMP1), vitamin D receptor, tumor necrosis factor-alpha, interleukin (IL)-1, and IL-10 genes were evaluated in 358 Cambodian patients with pulmonary TB and 106 tuberculin-positive control subjects.
It is possible that Mycobacterium tuberculosis (PPD)-specific IL-10 is expressed preemptively in unvaccinated (BCG scar-negative) individuals with a non-DR2 genetic background by chronic exposure in this area of endemicity and leads to pulmonary tuberculosis of adults.
The basis for this observation was studied by examining the Th1 (interleukin 2 [IL-2] and gamma interferon [IFN-gamma])- and Th2 (IL-10 and IL-4)-type cytokines produced in response to the 30-kDa Ag by peripheral blood mononuclear cells (PBMC) from patients with active pulmonary TB (n = 7) and from HHC who were tuberculin (purified protein derivative) skin test positive (n = 12).