Limits...
Stimulation through CD40 and TLR-4 Is an Effective Host Directed Therapy against Mycobacterium tuberculosis

View Article: PubMed Central - PubMed

ABSTRACT

Tuberculosis (TB) is the leading cause of morbidity and mortality among all infectious diseases. Failure of Bacillus Calmette Guerin as a vaccine and serious side-effects and toxicity due to long-term TB drug regime are the major hurdles associated with TB control. The problem is further compounded by the emergence of drug-resistance strains of Mycobacterium tuberculosis (Mtb). Consequently, it demands a serious attempt to explore safer and superior treatment approaches. Recently, an improved understanding of host–pathogen interaction has opened up new avenues for immunotherapy for treating TB. Although, dendritic cells (DCs) show a profound role in generating immunity against Mtb, their immunotherapeutic potential needs to be precisely investigated in controlling TB. Here, we have devised an approach of bolstering DCs efficacy against Mtb by delivering signals through CD40 and TLR-4 molecules. We found that DCs triggered through CD40 and TLR-4 showed increased secretion of IL-12, IL-6, and TNF-α. It also augmented autophagy. Interestingly, CD40 and TLR-4 stimulation along with the suboptimal dose of anti-TB drugs significantly fortified their efficacy to kill Mtb. Importantly, animals treated with the agonists of CD40 and TLR-4 boosted Th1 and Th17 immunity. Furthermore, it amplified the pool of memory CD4 T cells as well as CD8 T cells. Furthermore, substantial reduction in the bacterial burden in the lungs was observed. Notably, this adjunct therapy employing immunomodulators and chemotherapy can reinvigorate host immunity suppressed due to drugs and Mtb. Moreover, it would strengthen the potency of drugs in curing TB.

No MeSH data available.


C40.T4 treatment bolstered the T cells immunity in mice exposed to Mtb. Mtb-infected animals were administered C40.T4. After 50 days, mice were sacrificed and lymphocytes were isolated and cultured with purified protein derivative (6 μg/ml) for 48 h. Later, cells were stained for the expression of (A) CD44/CD69 on CD4 T cells isolated from the lungs; (B) CD44/CD69 on CD8 T cells isolated from the lungs; (C,D) CD44/CD69 on CD4 T cells isolated from the spleens. Number in the histograms indicates the percentage of CD44hi and CD69hi on CD4 and CD8 gated population. Splenocytes stimulated in vitro with PPD were stained for expression of (E) IFN-γ on CD4 T cells; (F) IFN-γ on CD8 T cells; (G) IL-17 on CD4 T cells. The bar diagrams illustrate percent population and results expressed as mean ± SD. DCs isolated from the lungs of Mtb-infected animals treated with C40.T4 were stained for the expression of (H) CD40; (I) CD86 and on CD11c + DCs. Number in the histogram indicates the mean ± SD of CD11c+ DCs expressing CD40 and CD86 population. The data are representative of two independent experiments (n = 4 mice/group). “*,” “**,” and “***” indicate p < 0.05, p < 0.01, and p < 0.001, respectively.
© Copyright Policy
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC5037235&req=5

Figure 7: C40.T4 treatment bolstered the T cells immunity in mice exposed to Mtb. Mtb-infected animals were administered C40.T4. After 50 days, mice were sacrificed and lymphocytes were isolated and cultured with purified protein derivative (6 μg/ml) for 48 h. Later, cells were stained for the expression of (A) CD44/CD69 on CD4 T cells isolated from the lungs; (B) CD44/CD69 on CD8 T cells isolated from the lungs; (C,D) CD44/CD69 on CD4 T cells isolated from the spleens. Number in the histograms indicates the percentage of CD44hi and CD69hi on CD4 and CD8 gated population. Splenocytes stimulated in vitro with PPD were stained for expression of (E) IFN-γ on CD4 T cells; (F) IFN-γ on CD8 T cells; (G) IL-17 on CD4 T cells. The bar diagrams illustrate percent population and results expressed as mean ± SD. DCs isolated from the lungs of Mtb-infected animals treated with C40.T4 were stained for the expression of (H) CD40; (I) CD86 and on CD11c + DCs. Number in the histogram indicates the mean ± SD of CD11c+ DCs expressing CD40 and CD86 population. The data are representative of two independent experiments (n = 4 mice/group). “*,” “**,” and “***” indicate p < 0.05, p < 0.01, and p < 0.001, respectively.

Mentions: Finally, we used this strategy in the experimental model of TB. The animals were aerosol challenged with Mtb and 21 days later inoculated with CD40A and TLR-4L. After 50 days, mice were sacrificed. The cells were isolated from the lungs and spleen and cultured with PPD for 48 h. Later, we monitored the expression of activation markers viz. CD44 and CD69 on CD4 T cells. Interestingly, we observed that animals injected with C40.T4, displayed higher levels of CD44 and CD69 on CD4 T cells (Figures 7A–D). Similar results were noted in the case of CD8 T cells (Figure 7B). Control groups constituting of individually administered CD40A or TLR-4L showed marginal change in the expression of activation markers. It implies the importance of synergism between C40.T4 molecules in reinvigorating immunity during Mtb infection.


Stimulation through CD40 and TLR-4 Is an Effective Host Directed Therapy against Mycobacterium tuberculosis
C40.T4 treatment bolstered the T cells immunity in mice exposed to Mtb. Mtb-infected animals were administered C40.T4. After 50 days, mice were sacrificed and lymphocytes were isolated and cultured with purified protein derivative (6 μg/ml) for 48 h. Later, cells were stained for the expression of (A) CD44/CD69 on CD4 T cells isolated from the lungs; (B) CD44/CD69 on CD8 T cells isolated from the lungs; (C,D) CD44/CD69 on CD4 T cells isolated from the spleens. Number in the histograms indicates the percentage of CD44hi and CD69hi on CD4 and CD8 gated population. Splenocytes stimulated in vitro with PPD were stained for expression of (E) IFN-γ on CD4 T cells; (F) IFN-γ on CD8 T cells; (G) IL-17 on CD4 T cells. The bar diagrams illustrate percent population and results expressed as mean ± SD. DCs isolated from the lungs of Mtb-infected animals treated with C40.T4 were stained for the expression of (H) CD40; (I) CD86 and on CD11c + DCs. Number in the histogram indicates the mean ± SD of CD11c+ DCs expressing CD40 and CD86 population. The data are representative of two independent experiments (n = 4 mice/group). “*,” “**,” and “***” indicate p < 0.05, p < 0.01, and p < 0.001, respectively.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC5037235&req=5

Figure 7: C40.T4 treatment bolstered the T cells immunity in mice exposed to Mtb. Mtb-infected animals were administered C40.T4. After 50 days, mice were sacrificed and lymphocytes were isolated and cultured with purified protein derivative (6 μg/ml) for 48 h. Later, cells were stained for the expression of (A) CD44/CD69 on CD4 T cells isolated from the lungs; (B) CD44/CD69 on CD8 T cells isolated from the lungs; (C,D) CD44/CD69 on CD4 T cells isolated from the spleens. Number in the histograms indicates the percentage of CD44hi and CD69hi on CD4 and CD8 gated population. Splenocytes stimulated in vitro with PPD were stained for expression of (E) IFN-γ on CD4 T cells; (F) IFN-γ on CD8 T cells; (G) IL-17 on CD4 T cells. The bar diagrams illustrate percent population and results expressed as mean ± SD. DCs isolated from the lungs of Mtb-infected animals treated with C40.T4 were stained for the expression of (H) CD40; (I) CD86 and on CD11c + DCs. Number in the histogram indicates the mean ± SD of CD11c+ DCs expressing CD40 and CD86 population. The data are representative of two independent experiments (n = 4 mice/group). “*,” “**,” and “***” indicate p < 0.05, p < 0.01, and p < 0.001, respectively.
Mentions: Finally, we used this strategy in the experimental model of TB. The animals were aerosol challenged with Mtb and 21 days later inoculated with CD40A and TLR-4L. After 50 days, mice were sacrificed. The cells were isolated from the lungs and spleen and cultured with PPD for 48 h. Later, we monitored the expression of activation markers viz. CD44 and CD69 on CD4 T cells. Interestingly, we observed that animals injected with C40.T4, displayed higher levels of CD44 and CD69 on CD4 T cells (Figures 7A–D). Similar results were noted in the case of CD8 T cells (Figure 7B). Control groups constituting of individually administered CD40A or TLR-4L showed marginal change in the expression of activation markers. It implies the importance of synergism between C40.T4 molecules in reinvigorating immunity during Mtb infection.

View Article: PubMed Central - PubMed

ABSTRACT

Tuberculosis (TB) is the leading cause of morbidity and mortality among all infectious diseases. Failure of Bacillus Calmette Guerin as a vaccine and serious side-effects and toxicity due to long-term TB drug regime are the major hurdles associated with TB control. The problem is further compounded by the emergence of drug-resistance strains of Mycobacterium tuberculosis (Mtb). Consequently, it demands a serious attempt to explore safer and superior treatment approaches. Recently, an improved understanding of host&ndash;pathogen interaction has opened up new avenues for immunotherapy for treating TB. Although, dendritic cells (DCs) show a profound role in generating immunity against Mtb, their immunotherapeutic potential needs to be precisely investigated in controlling TB. Here, we have devised an approach of bolstering DCs efficacy against Mtb by delivering signals through CD40 and TLR-4 molecules. We found that DCs triggered through CD40 and TLR-4 showed increased secretion of IL-12, IL-6, and TNF-&alpha;. It also augmented autophagy. Interestingly, CD40 and TLR-4 stimulation along with the suboptimal dose of anti-TB drugs significantly fortified their efficacy to kill Mtb. Importantly, animals treated with the agonists of CD40 and TLR-4 boosted Th1 and Th17 immunity. Furthermore, it amplified the pool of memory CD4 T cells as well as CD8 T cells. Furthermore, substantial reduction in the bacterial burden in the lungs was observed. Notably, this adjunct therapy employing immunomodulators and chemotherapy can reinvigorate host immunity suppressed due to drugs and Mtb. Moreover, it would strengthen the potency of drugs in curing TB.

No MeSH data available.