scholarly journals Vitamin D Rescues Impaired Mycobacterium tuberculosis-Mediated Tumor Necrosis Factor Release in Macrophages of HIV-Seropositive Individuals through an Enhanced Toll-Like Receptor Signaling PathwayIn Vitro

2012 ◽  
Vol 81 (1) ◽  
pp. 2-10 ◽  
Author(s):  
Asha Anandaiah ◽  
Sanjeev Sinha ◽  
Medhavi Bole ◽  
Surendra K. Sharma ◽  
Narendra Kumar ◽  
...  

Mycobacterium tuberculosisdisease represents an enormous global health problem, with exceptionally high morbidity and mortality in HIV-seropositive (HIV+) persons. Alveolar macrophages from HIV+persons demonstrate specific and targeted impairment of critical host cell responses, including impairedM. tuberculosis-mediated tumor necrosis factor (TNF) release and macrophage apoptosis. Vitamin D may promote anti-M. tuberculosisresponses through upregulation of macrophage NO, NADPH oxidase, cathelicidin, and autophagy mechanisms, but whether vitamin D promotes anti-M. tuberculosismechanisms in HIV+macrophages is not known. In the current study, human macrophages exposed toM. tuberculosisdemonstrated robust release of TNF, IκB degradation, and NF-κB nuclear translocation, and these responses were independent of vitamin D pretreatment. In marked contrast, HIV+U1 human macrophages exposed toM. tuberculosisdemonstrated very low TNF release and no significant IκB degradation or NF-κB nuclear translocation, whereas vitamin D pretreatment restored these critical responses. The vitamin D-mediated restored responses were dependent in part on macrophage CD14 expression. Importantly, similar response patterns were observed with clinically relevant human alveolar macrophages from healthy individuals and asymptomatic HIV+persons at high clinical risk ofM. tuberculosisinfection. Taken together with the observation that local bronchoalveolar lavage fluid (BALF) levels of vitamin D are severely deficient in HIV+persons, the data from this study demonstrate that exogenous vitamin D can selectively rescue impaired critical innate immune responsesin vitroin alveolar macrophages from HIV+persons at risk forM. tuberculosisdisease, supporting a potential role for exogenous vitamin D as a therapeutic adjuvant inM. tuberculosisinfection in HIV+persons.

2017 ◽  
Vol 85 (3) ◽  
Author(s):  
Alvaro Torres-Huerta ◽  
Tomás Villaseñor ◽  
Angel Flores-Alcantar ◽  
Cristina Parada ◽  
Estefanía Alemán-Navarro ◽  
...  

ABSTRACT Mycobacterium tuberculosis is the causal agent of tuberculosis. Tumor necrosis factor alpha (TNF-α), transforming growth factor β (TGF-β), and gamma interferon (IFN-γ) secreted by activated macrophages and lymphocytes are considered essential to contain Mycobacterium tuberculosis infection. The CD43 sialomucin has been reported to act as a receptor for bacilli through its interaction with the chaperonin Cpn60.2, facilitating mycobacterium-macrophage contact. We report here that Cpn60.2 induces both human THP-1 cells and mouse-derived bone marrow-derived macrophages (BMMs) to produce TNF-α and that this production is CD43 dependent. In addition, we present evidence that the signaling pathway leading to TNF-α production upon interaction with Cpn60.2 requires active Src family kinases, phospholipase C-γ (PLC-γ), phosphatidylinositol 3-kinase (PI3K), p38, and Jun N-terminal protein kinase (JNK), both in BMMs and in THP-1 cells. Our data highlight the role of CD43 and Cpn60.2 in TNF-α production and underscore an important role for CD43 in the host-mycobacterium interaction.


2012 ◽  
Vol 80 (11) ◽  
pp. 3858-3868 ◽  
Author(s):  
Jillian M. Richmond ◽  
Elizabeth R. Duffy ◽  
Jinhee Lee ◽  
Kavon Kaboli ◽  
Daniel G. Remick ◽  
...  

ABSTRACTPrimaryMycobacterium tuberculosisinfection results in granuloma formation in lung tissue. A granuloma encapsulates mycobacterium-containing cells, thereby preventing dissemination and further infection. Tumor necrosis factor alpha (TNF-α) is a host-protective cytokine duringM. tuberculosisinfection due to its role in promoting and sustaining granuloma formation. TNF activity is regulated through the production of soluble TNF receptors (sTNFRI and sTNFRII). Therefore, we examined the potential production of endogenous sTNFRs duringM. tuberculosisinfection. Using the murine model of aerosolM. tuberculosisinfection, we determined that levels of sTNFR production were elevated in bronchoalveolar lavage fluid 1 month following infection. An investigation ofM. tuberculosiscell wall components identified that the known virulence factor mannose-capped lipoarabinomannan (ManLAM) was sufficient to induce sTNFR production, with sTNFRII being produced preferentially compared with sTNFRI. ManLAM stimulated the release of sTNFRs without TNF production, which corresponded to an increase in TNF-α-converting enzyme (TACE) activity. To determine the relevance of these findings, serum samples fromM. tuberculosis-infected patients were tested and found to have an increase in the sTNFRII/sTNFRI ratio. These data identify a mechanism by whichM. tuberculosisinfection can promote the neutralization of TNF and furthermore suggest the potential use of the sTNFRII/sTNFRI ratio as an indicator of tuberculosis disease.


2006 ◽  
Vol 80 (16) ◽  
pp. 8248-8258 ◽  
Author(s):  
Vasile Laza-Stanca ◽  
Luminita A. Stanciu ◽  
Simon D. Message ◽  
Michael R. Edwards ◽  
James E. Gern ◽  
...  

ABSTRACT Rhinoviruses (RV) are the major cause of acute exacerbations of asthma and chronic obstructive pulmonary disease (COPD). Rhinoviruses have been shown to activate macrophages, but rhinovirus replication in macrophages has not been reported. Tumor necrosis factor alpha (TNF-α) is implicated in the pathogenesis of acute exacerbations, but its cellular source and mechanisms of induction by virus infection are unclear. We hypothesized that rhinovirus replication in human macrophages causes activation and nuclear translocation of NF-κB, leading to TNF-α production. Using macrophages derived from the human monocytic cell line THP-1 and from primary human monocytes, we demonstrated that rhinovirus replication was productive in THP-1 macrophages, leading to release of infectious virus into supernatants, but was limited in monocyte-derived macrophages, likely due to type I interferon production, which was robust in monocyte-derived but deficient in THP-1-derived macrophages. Similar to bronchial epithelial cells, only small numbers of cells supported complete virus replication. We demonstrated RV-induced activation of NF-κB and colocalization of p65/NF-κB nuclear translocation with virus replication in both macrophage types. The infection induced TNF-α release in a time- and dose-dependent, RV serotype- and receptor-independent manner and was largely (THP-1 derived) or completely (monocyte derived) dependent upon virus replication. Finally, we established the requirement for NF-κB but not p38 mitogen-activated protein kinase in induction of TNF-α. These data suggest RV infection of macrophages may be an important source of proinflammatory cytokines implicated in the pathogenesis of exacerbations of asthma and COPD. They also confirm inhibition of NF-κB as a promising target for development of new therapeutic intervention strategies.


2007 ◽  
Vol 76 (1) ◽  
pp. 351-360 ◽  
Author(s):  
Deirdre M. Kelly ◽  
Annemieke M. C. ten Bokum ◽  
Seonadh M. O'Leary ◽  
Mary P. O'Sullivan ◽  
Joseph Keane

ABSTRACT Human macrophages infected with Mycobacterium tuberculosis may undergo apoptosis. Macrophage apoptosis contributes to the innate immune response against M. tuberculosis by containing and limiting the growth of mycobacteria and also by depriving the bacillus of its niche cell. Apoptosis of infected macrophages is well documented; however, bystander apoptosis of uninfected macrophages has not been described in the setting of M. tuberculosis. We observed that uninfected human macrophages underwent significant bystander apoptosis 48 and 96 h after they came into contact with macrophages infected with avirulent M. tuberculosis. The bystander apoptosis was significantly greater than the background apoptosis observed in uninfected control cells cultured for the same length of time. There was no evidence of the involvement of tumor necrosis factor alpha, Fas, tumor necrosis factor-related apoptosis-inducing ligand, transforming growth factor β, Toll-like receptor 2, or MyD88 in contact-mediated bystander apoptosis. This newly described phenomenon may further limit the spread of M. tuberculosis by eliminating the niche cells on which the bacillus relies.


2001 ◽  
Vol 21 (12) ◽  
pp. 3986-3994 ◽  
Author(s):  
Anne Devin ◽  
Yong Lin ◽  
Shoji Yamaoka ◽  
Zhiwei Li ◽  
Michael Karin ◽  
...  

ABSTRACT The activation of IκB kinase (IKK) is a key step in the nuclear translocation of the transcription factor NF-κB. IKK is a complex composed of three subunits: IKKα, IKKβ, and IKKγ (also called NEMO). In response to the proinflammatory cytokine tumor necrosis factor (TNF), IKK is activated after being recruited to the TNF receptor 1 (TNF-R1) complex via TNF receptor-associated factor 2 (TRAF2). We found that the IKKα and IKKβ catalytic subunits are required for IKK-TRAF2 interaction. This interaction occurs through the leucine zipper motif common to IKKα, IKKβ, and the RING finger domain of TRAF2, and either IKKα or IKKβ alone is sufficient for the recruitment of IKK to TNF-R1. Importantly, IKKγ is not essential for TNF-induced IKK recruitment to TNF-R1, as this occurs efficiently in IKKγ-deficient cells. Using TRAF2−/− cells, we demonstrated that the TNF-induced interaction between IKKγ and the death domain kinase RIP is TRAF2 dependent and that one possible function of this interaction is to stabilize the IKK complex when it interacts with TRAF2.


2013 ◽  
Vol 87 (23) ◽  
pp. 12935-12948 ◽  
Author(s):  
Jie Zhang ◽  
Kezhen Wang ◽  
Shuai Wang ◽  
Chunfu Zheng

NF-κB plays central roles in regulation of diverse biological processes, including innate and adaptive immunity and inflammation. HSV-1 is the archetypal member of the alphaherpesviruses, with a large genome encoding over 80 viral proteins, many of which are involved in virus-host interactions and show immune modulatory capabilities. In this study, we demonstrated that the HSV-1 ICP0 protein, a viral E3 ubiquitin ligase, was shown to significantly suppress tumor necrosis factor alpha (TNF-α)-mediated NF-κB activation. ICP0 was demonstrated to bind to the NF-κB subunits p65 and p50 by coimmunoprecipitation analysis. ICP0 bound to the Rel homology domain (RHD) of p65. Fluorescence microscopy demonstrated that ICP0 abolished nuclear translocation of p65 upon TNF-α stimulation. Also, ICP0 degraded p50 via its E3 ubiquitin ligase activity. The RING finger (RF) domain mutant ICP0 (ICP0-RF) lost its ability to inhibit TNF-α-mediated NF-κB activation and p65 nuclear translocation and degrade p50. Notably, the RF domain of ICP0 was sufficient to interact with p50 and abolish NF-κB reporter gene activity. Here, it is for the first time shown that HSV-1 ICP0 interacts with p65 and p50, degrades p50 through the ubiquitin-proteasome pathway, and prevents NF-κB-dependent gene expression, which may contribute to immune evasion and pathogenesis of HSV-1.


Immunity ◽  
2015 ◽  
Vol 43 (6) ◽  
pp. 1125-1136 ◽  
Author(s):  
Nelson C. Di Paolo ◽  
Shahin Shafiani ◽  
Tracey Day ◽  
Thalia Papayannopoulou ◽  
David W. Russell ◽  
...  

1997 ◽  
Vol 185 (1) ◽  
pp. 55-64 ◽  
Author(s):  
Andrew D. Badley ◽  
David Dockrell ◽  
Margaret Simpson ◽  
Ron Schut ◽  
David H. Lynch ◽  
...  

Apoptosis of bystander uninfected CD4+ T lymphocytes by neighboring HIV-infected cells is observed in cell culture and in lymphoid tissue of HIV-infected individuals. This study addresses whether antigen-presenting cells such as human macrophages mediate apoptosis of CD4+ T cells from HIV-infected individuals. Uninfected human macrophages, and to a larger degree, HIV-infected macrophages mediate apoptosis of T cells from HIV-infected, but not from uninfected control individuals. This macrophage-dependent killing targets CD4+, but not CD8+ T lymphocytes from HIV-infected individuals, and direct contact between macrophages and lymphocytes is required. Additional analyses indicated that the apoptosis-inducing ligands, FasL and tumor necrosis factor (TNF), mediate this macrophage-induced apoptosis of CD4+ T cells. These results support a role for macrophage-associated FasL and TNF in the selective depletion of CD4+ T cells in HIV-infected individuals.


2001 ◽  
Vol 69 (8) ◽  
pp. 4823-4830 ◽  
Author(s):  
Véronique Jubier-Maurin ◽  
Rose-Anne Boigegrain ◽  
Axel Cloeckaert ◽  
Antoine Gross ◽  
Maria-Teresa Alvarez-Martinez ◽  
...  

ABSTRACT Brucella spp. can establish themselves and cause disease in humans and animals. The mechanisms by whichBrucella spp. evade the antibacterial defenses of their host, however, remain largely unknown. We have previously reported that live brucellae failed to induce tumor necrosis factor alpha (TNF-α) production upon human macrophage infection. This inhibition is associated with a nonidentified protein that is released into culture medium. Outer membrane proteins (OMPs) of gram-negative bacteria have been shown to modulate macrophage functions, including cytokine production. Thus, we have analyzed the effects of two major OMPs (Omp25 and Omp31) of Brucella suis 1330 (wild-type [WT] B. suis) on TNF-α production. For this purpose, omp25and omp31 null mutants of B. suis(Δomp25 B. suis and Δomp31 B. suis, respectively) were constructed and analyzed for the ability to activate human macrophages to secrete TNF-α. We showed that, in contrast to WTB. suis or Δomp31 B. suis, Δomp25 B. suis induced TNF-α production when phagocytosed by human macrophages. The complementation of Δomp25 B. suis with WT omp25 (Δomp25-omp25 B. suis mutant) significantly reversed this effect: Δomp25-omp25 B. suis-infected macrophages secreted significantly less TNF-α than did macrophages infected with the Δomp25 B. suismutant. Furthermore, pretreatment of WT B. suis with an anti-Omp25 monoclonal antibody directed against an epitope exposed at the surface of the bacteria resulted in substancial TNF-α production during macrophage infection. These observations demonstrated that Omp25 of B. suis is involved in the negative regulation of TNF-α production upon infection of human macrophages.


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