scholarly journals PM2.5 Mediated Alterations In The In Vitro Human Granuloma Resulting In Reactivation Of Mycobacteria

Author(s):  
Athisankaran Punniyamurthy ◽  
Sumedha Sharma ◽  
Khushpreet Kaur ◽  
Uma Nahar Saikia ◽  
Ravindra Khaiwal ◽  
...  

Abstract Exposure to pollutants diminishes the immune response to mycobacterial antigens relevant to contain the infection in the granuloma, thus leading to reactivation of latent bacilli. Present study was therefore designed based on the hypothesis that exposure to particulate matter pollutant PM2.5 affects the granuloma formation and reactivation of latent mycobacterial bacilli contained in the granuloma. For the extraction of PM2.5, based on initial standardizations, teflon filter was selected over the quartz filter. Two different approaches were used to study the effect of PM2.5 on the human PBMCs granuloma formed by Mycobacterium bovis BCG at MOI 0.1. In the first approach, granuloma formed in the presence of PM2.5 was loosely packed and ill-defined with significant downregulation of dormancy associated mycobacterial genes, upregulation of reactivation associated rpfB gene along with a significant increase in TNFα level without any change in the bacterial load in terms of CFUs. In the second approach, PM2.5 treatment of already established human PBMCs granuloma formed with M. bovis BCG also led to its disruption. Although, in these conditions, downregulation of dormancy associated genes was observed but there was also a decrease in the expression of reactivation associated rpfB gene without any change in the cytokine levels. Therefore, it can be inferred that in the presence of PM2.5, there is poor granuloma formation along with a change in mycobacterial gene expression characteristics of active bacilli and alteration in host immune response without any significant changes following treatment of already established granuloma with the pollutant.

2006 ◽  
Vol 74 (2) ◽  
pp. 1436-1441 ◽  
Author(s):  
Julia A. Tree ◽  
Michael J. Elmore ◽  
Sajid Javed ◽  
Ann Williams ◽  
Philip D. Marsh

ABSTRACT Immune responses in the guinea pig model are understudied because of a lack of commercial reagents. We have developed a custom-made guinea pig oligonucleotide microarray (81 spots) and have examined the gene expression profile of splenocytes restimulated in vitro from Mycobacterium bovis BCG-vaccinated and naive animals. Eleven genes were significantly (P < 0.05) up-regulated following vaccination, indicating a Th1-type response. These results show that microarrays can be used to more fully define immune profiles of guinea pigs.


2018 ◽  
Vol 17 (4) ◽  
pp. 1235-1246 ◽  
Author(s):  
Abdelnaser A. Badawy ◽  
Mohammed A. El-Magd ◽  
Sana A. AlSadrah

Background/Objectives: In the Middle East, people consume camel milk regularly as it is believed to improve immunity against diseases and decrease the risk for cancer. Recently, it was noted that most of the beneficial effects of milk come from their nanoparticles, especially exosomes. Herein, we evaluated the anticancer potential of camel milk and its exosomes on MCF7 breast cancer cells (in vitro and in vivo) and investigated the possible underlying molecular mechanism of action. Methods/Results: Administration of camel milk (orally) and its exosomes (orally and by local injection) decreased breast tumor progression as evident by ( a) higher apoptosis (indicated by higher DNA fragmentation, caspase-3 activity, Bax gene expression, and lower Bcl2 gene expression), ( b) remarkable inhibition of oxidative stress (decrease in MDA levels and iNOS gene expression); ( c) induction of antioxidant status (increased activities of SOD, CAT, and GPX), ( d) notable reduction in expression of inflammation-( IL1b, NFκB), angiogenesis-( VEGF) and metastasis-( MMP9, ICAM1) related genes; and ( e) higher immune response (high number of CD+4, CD+8, NK1.1 T cells in spleen). Conclusions: Overall, administration of camel milk–derived exosomes showed better anticancer effect, but less immune response, than treatment by camel milk. Moreover, local injection of exosomes led to better improvement than oral administration. These findings suggest that camel milk and its exosomes have anticancer effect possibly through induction of apoptosis and inhibition of oxidative stress, inflammation, angiogenesis and metastasis in the tumor microenvironment. Thus, camel milk and its exosomes could be used as an anticancer agent for cancer treatment.


Author(s):  
Hyun Soo Lee ◽  
Sehyun Han ◽  
Jeong-Won Seo ◽  
Ki-Joon Jeon

Ambient particulate matter (PM), a major component of air pollution, aggravates ocular discomfort and inflammation, similarly to dry eye disease (DED) or allergies. However, the mechanism(s) by which PM induces the ocular inflammatory response is unknown. This study investigated the immunological response of traffic-related fine particulate matter (PM2.5) on the ocular surface in a murine model. C57BL/6 mice were exposed by topical application to PM2.5 or vehicle for 14 days to induce experimental environmental ocular disease. Corneal fluorescein staining and the number of ocular inflammatory cells were assessed in both groups. The expression of IL-1β, IL-6, tumor necrosis factor (TNF)-α, and mucin 5AC (MUC5AC) in the ocular surface were evaluated by real-time PCR. An immunohistochemical assay evaluated apoptosis and goblet cell density. ELISA was used to determine the levels of serum IgE and cytokines of Type 1 helper (Th1) and Type 2 helper (Th2) cells after in vitro stimulation of T cells in the draining lymph nodes (LNs). Exposure to traffic-related PM2.5 significantly increased corneal fluorescein staining and cellular toxicity in the corneal epithelium compared with the vehicle control. A significant increase in the number of CD11b+ cells on the central cornea and mast cells in the conjunctiva was observed in the PM2.5 group. Exposure to PM2.5 was associated with a significant increase in the corneal or conjunctival expression of IL-1β, IL-6, TNF, and MUC5AC compared to the vehicle, and increased maturation of dendric cells (DCs) (MHC-IIhighCD11c+) in draining LNs. In addition, PM2.5 exposure increased the level of serum IgE and Th2 cytokine production in draining LNs on day 14. In conclusion, exposure to traffic-related PM2.5 caused ocular surface damage and inflammation, which induced DC maturation and the Th2-cell-dominant allergic immune response in draining LNs.


Computation ◽  
2018 ◽  
Vol 6 (4) ◽  
pp. 58 ◽  
Author(s):  
Simeone Marino ◽  
Caitlin Hult ◽  
Paul Wolberg ◽  
Jennifer Linderman ◽  
Denise Kirschner

Within the first 2–3 months of a Mycobacterium tuberculosis (Mtb) infection, 2–4 mm spherical structures called granulomas develop in the lungs of the infected hosts. These are the hallmark of tuberculosis (TB) infection in humans and non-human primates. A cascade of immunological events occurs in the first 3 months of granuloma formation that likely shapes the outcome of the infection. Understanding the main mechanisms driving granuloma development and function is key to generating treatments and vaccines. In vitro, in vivo, and in silico studies have been performed in the past decades to address the complexity of granuloma dynamics. This study builds on our previous 2D spatio-temporal hybrid computational model of granuloma formation in TB (GranSim) and presents for the first time a more realistic 3D implementation. We use uncertainty and sensitivity analysis techniques to calibrate the new 3D resolution to non-human primate (NHP) experimental data on bacterial levels per granuloma during the first 100 days post infection. Due to the large computational cost associated with running a 3D agent-based model, our major goal is to assess to what extent 2D and 3D simulations differ in predictions for TB granulomas and what can be learned in the context of 3D that is missed in 2D. Our findings suggest that in terms of major mechanisms driving bacterial burden, 2D and 3D models return very similar results. For example, Mtb growth rates and molecular regulation mechanisms are very important both in 2D and 3D, as are cellular movement and modulation of cell recruitment. The main difference we found was that the 3D model is less affected by crowding when cellular recruitment and movement of cells are increased. Overall, we conclude that the use of a 2D resolution in GranSim is warranted when large scale pilot runs are to be performed and if the goal is to determine major mechanisms driving infection outcome (e.g., bacterial load). To comprehensively compare the roles of model dimensionality, further tests and experimental data will be needed to expand our conclusions to molecular scale dynamics and multi-scale resolutions.


Cells ◽  
2019 ◽  
Vol 8 (5) ◽  
pp. 415 ◽  
Author(s):  
Naveed Sabir ◽  
Tariq Hussain ◽  
Yi Liao ◽  
Jie Wang ◽  
Yinjuan Song ◽  
...  

Mycobacterium bovis (M. bovis) is a member of the Mycobacterium tuberculosis (Mtb) complex causing bovine tuberculosis (TB) and imposing a high zoonotic threat to human health. Kallikreins (KLKs) belong to a subgroup of secreted serine proteases. As their role is established in various physiological and pathological processes, it is likely that KLKs expression may mediate a host immune response against the M. bovis infection. In the current study, we report in vivo and in vitro upregulation of KLK12 in the M. bovis infection. To define the role of KLK12 in immune response regulation of murine macrophages, we produced KLK12 knockdown bone marrow derived macrophages (BMDMs) by using siRNA transfection. Interestingly, the knockdown of KLK12 resulted in a significant downregulation of autophagy and apoptosis in M. bovis infected BMDMs. Furthermore, we demonstrated that this KLK12 mediated regulation of autophagy and apoptosis involves mTOR/AMPK/TSC2 and BAX/Bcl-2/Cytochrome c/Caspase 3 pathways, respectively. Similarly, inflammatory cytokines IL-1β, IL-6, IL-12 and TNF-α were significantly downregulated in KLK12 knockdown macrophages but the difference in IL-10 and IFN-β expression was non-significant. Taken together, these findings suggest that upregulation of KLK12 in M. bovis infected murine macrophages plays a substantial role in the protective immune response regulation by modulating autophagy, apoptosis and pro-inflammatory pathways. To our knowledge, this is the first report on expression and the role of KLK12 in the M. bovis infection and the data may contribute to a new paradigm for diagnosis and treatment of bovine TB.


2008 ◽  
Vol 76 (5) ◽  
pp. 2227-2234 ◽  
Author(s):  
Debbie M. Hunt ◽  
José W. Saldanha ◽  
John F. Brennan ◽  
Pearline Benjamin ◽  
Molly Strom ◽  
...  

ABSTRACT Single nucleotide polymorphisms (SNPs) are present in the global transcriptional regulator cyclic AMP (cAMP) receptor protein (CRP) of the attenuated vaccine strain Mycobacterium bovis, bacillus Calmette-Guérin (BCG). We have found that these SNPs resulted in small but significant changes in the expression of a number of genes in M. tuberculosis when a deletion of the Rv3676 CRP was complemented by the BCG allele, compared to complementation by the M. tuberculosis allele. We can explain these changes in gene expression by modeling the structure of the mycobacterial protein on the known structure of CRP from Escherichia coli. Thus, the SNP change in the DNA-binding domain, Lys178, is predicted to form a hydrogen bond with the phosphate backbone of the DNA, as does the equivalent residue in E. coli, whereas Glu178 in M. tuberculosis/M. bovis does not, thus explaining the stronger binding reported for CRP of BCG to CRP-binding sites in mycobacterial DNA. In contrast, the SNP change in the nucleotide binding domain (Leu47Pro) is predicted to result in the loss of one hydrogen bond, which is accommodated by the structure, and would not therefore be expected to cause any change in function relating to cAMP binding. The BCG allele fully complemented the growth defect caused by the deletion of the Rv3676 protein in M. tuberculosis, both in vitro and in macrophage and mouse infections, suggesting that these SNPs do not play any role in the attenuation of BCG. However, they may have allowed BCG to grow better under the in vitro-selective conditions used in its derivation from the M. bovis wild type.


Nature ◽  
1984 ◽  
Vol 307 (5949) ◽  
pp. 381-382 ◽  
Author(s):  
Masataka Nakamura ◽  
Tim Manser ◽  
Gregory D. N. Pearson ◽  
Michael J. Daley ◽  
Malcolm L. Gefter

1995 ◽  
Vol 112 (1-6) ◽  
pp. 391-400 ◽  
Author(s):  
M. Zanotti Casati ◽  
M. Longeri ◽  
M. Polli ◽  
G. Ceriotti ◽  
G. Poli

2017 ◽  
Vol 2017 ◽  
pp. 1-9 ◽  
Author(s):  
Sultan Alsuhaibani ◽  
Masood A. Khan

The present study was aimed at determining the activity of aqueous and methanolic extracts of Tinospora cordifolia (AETC and METC) against Salmonella typhimurium. In vitro anti-Salmonella activity of T. cordifolia was determined through the broth dilution and agar well diffusion assays. The immune-stimulating potential of AETC or METC was determined by measuring the cytokine levels in the culture supernatants of treated murine J774 macrophages. Antibacterial activity of AETC or METC was determined by treating S. typhimurium-infected macrophages and BALB/C mice. The toxicity of AETC or METC was determined by measuring the levels of liver inflammation markers aspartate transaminase (AST) and alanine transaminase (ALT) and antioxidant enzymes. Macrophages treated with AETC or METC secreted greater levels of IFN-γ, TNF-α, and IL-1β. METC showed greater activity against S. typhimurium infection in macrophages and mice as well. Treatment with METC resulted in increased survival and reduced bacterial load in S. typhimurium-infected mice. Moreover, METC or AETC treatment reduced the liver inflammation and rescued the levels of antioxidant enzymes in S. typhimurium-infected mice. The results of the present study suggest that the use of T. cordifolia may act as a double-edged sword in combating salmonellosis.


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