Ontained a higher frequency of cells producing another inflammatory cytokine, TNF-a.

September 18, 2017

Ontained a higher frequency of cells producing another inflammatory cytokine, TNF-a. Besides IFN-c, TNF-a is also a key molecule in host immunity to tuberculosis. The lack of this cytokine leads to reduced expression of immune mediators and increased susceptibility to primary infection with M. tuberculosis, and depletion of TNF after infection results in reactivation of latent disease [29,30,31,32]. Despite studies have failed to Title Loaded From File control M. Title Loaded From File tuberculosis in human host cells in vitro, its role in vivo is clearly shown by the reactivation of latent disease upon anti NF treatment [33,34,35]. The high commitment of DN Tcells to cytokines known to be effector mediators in controlling mycobacterium suggests their participation in the immune responses during this disease. Higher frequencies of CD4+ and CD8+ ab T-cells producing the modulatory cytokine IL-10 were found in TB-infected patients. In fact, studies have been demonstrated that newly diagnosed patients, before treatment produce high levels of IL-10 and low amounts of IL-12, while the reverse was true in healthy controls and successfully treated patients [36]. IL-10 suppresses macrophage functions, including killing of intracellular pathogens and TNF and IL-12 production required for Th1 responses [37,38]. Due to its regulatory profile, it is likely that IL-10 induction during tuberculosis will affect the course of disease. IL-10 message is induced during experimental infection with a number of mycobacterial species, and has been correlated with enhanced disease in TB patients [39,40]. Moreover, in an animal model of tuberculosis, the deficiency of IL-10 reduced bacterial load in lungs with decreased dissemination 18297096 to the spleen, which was preceded by an earlier and enhanced Th1-type response [41]. Interestingly, DN ab T-cells from TB-infected patients do not produce more IL-10 than the same subset from healthy donors, in 1531364 opposed to higher frequencies of IFN-c found in DN ab T-cells from these patients. The opposite is observed in CD4+ ab T-cellssubset, where no differences were found in IFN-c production among groups, but IL-10 producing cells were prominent among CD4+ ab T-cells from TB patients, especially those presenting the non-severe form of the disease. This was an interesting finding, and might explain in part the fact that DN ab T-cells are able to maintain for longer their ability to produce inflammatory cytokines in patients presenting the non-severe form of the disease. On the contrary, higher frequencies of IL-10 producing cells were found in cd DN T-cells from TB-infected patients, due to the severe form of tuberculosis, which together with the lower IFN-c production suggest a modulatory role of cd DN T-cells during tuberculosis. Although it has been shown that the cd T-cells are expanded within PBMC from patients presenting this disease upon stimulation in vitro and from health care workers who were tuberculin skin test positive and who had constant contact with patients with active tuberculosis, the precise role of this subpopulation in tuberculosis is still not clear [21,42]. Thus, in TB-infected patients, the inflammatory components that reside within the ab and cd DN T-cell subpopulations are maintained among patients presenting the non-severe form of the disease, while the modulatory component within cd DN T-cells takes place in more advanced forms of tuberculosis. The inflammatory profile in nsTB patients will favor the activity of DN T-cells as inducers of cell-medi.Ontained a higher frequency of cells producing another inflammatory cytokine, TNF-a. Besides IFN-c, TNF-a is also a key molecule in host immunity to tuberculosis. The lack of this cytokine leads to reduced expression of immune mediators and increased susceptibility to primary infection with M. tuberculosis, and depletion of TNF after infection results in reactivation of latent disease [29,30,31,32]. Despite studies have failed to control M. tuberculosis in human host cells in vitro, its role in vivo is clearly shown by the reactivation of latent disease upon anti NF treatment [33,34,35]. The high commitment of DN Tcells to cytokines known to be effector mediators in controlling mycobacterium suggests their participation in the immune responses during this disease. Higher frequencies of CD4+ and CD8+ ab T-cells producing the modulatory cytokine IL-10 were found in TB-infected patients. In fact, studies have been demonstrated that newly diagnosed patients, before treatment produce high levels of IL-10 and low amounts of IL-12, while the reverse was true in healthy controls and successfully treated patients [36]. IL-10 suppresses macrophage functions, including killing of intracellular pathogens and TNF and IL-12 production required for Th1 responses [37,38]. Due to its regulatory profile, it is likely that IL-10 induction during tuberculosis will affect the course of disease. IL-10 message is induced during experimental infection with a number of mycobacterial species, and has been correlated with enhanced disease in TB patients [39,40]. Moreover, in an animal model of tuberculosis, the deficiency of IL-10 reduced bacterial load in lungs with decreased dissemination 18297096 to the spleen, which was preceded by an earlier and enhanced Th1-type response [41]. Interestingly, DN ab T-cells from TB-infected patients do not produce more IL-10 than the same subset from healthy donors, in 1531364 opposed to higher frequencies of IFN-c found in DN ab T-cells from these patients. The opposite is observed in CD4+ ab T-cellssubset, where no differences were found in IFN-c production among groups, but IL-10 producing cells were prominent among CD4+ ab T-cells from TB patients, especially those presenting the non-severe form of the disease. This was an interesting finding, and might explain in part the fact that DN ab T-cells are able to maintain for longer their ability to produce inflammatory cytokines in patients presenting the non-severe form of the disease. On the contrary, higher frequencies of IL-10 producing cells were found in cd DN T-cells from TB-infected patients, due to the severe form of tuberculosis, which together with the lower IFN-c production suggest a modulatory role of cd DN T-cells during tuberculosis. Although it has been shown that the cd T-cells are expanded within PBMC from patients presenting this disease upon stimulation in vitro and from health care workers who were tuberculin skin test positive and who had constant contact with patients with active tuberculosis, the precise role of this subpopulation in tuberculosis is still not clear [21,42]. Thus, in TB-infected patients, the inflammatory components that reside within the ab and cd DN T-cell subpopulations are maintained among patients presenting the non-severe form of the disease, while the modulatory component within cd DN T-cells takes place in more advanced forms of tuberculosis. The inflammatory profile in nsTB patients will favor the activity of DN T-cells as inducers of cell-medi.