scholarly journals Regulation of Interferon-γ receptor (IFN-γR) expression in macrophages during Mycobacterium tuberculosis infection

2020 ◽  
Vol 11 (1) ◽  
pp. 76-85
Author(s):  
Gunjan Kak ◽  
Brijendra K Tiwari ◽  
Yogendra Singh ◽  
Krishnamurthy Natarajan
Keyword(s):  
Mycobacterium Tuberculosis ◽  
Mononuclear Cells ◽  
Second Messengers ◽  
Surface Expression ◽  
Interferon Γ ◽  
Fine Tuning ◽  
Mycobacterium Tuberculosis Infection ◽  
Peripheral Blood Mononuclear ◽  
Negative Role ◽  
Ifn Γ

AbstractInterferon-gamma (IFN-γ) is a key cytokine that mediates immunity to tuberculosis (TB). Mycobacterium tuberculosis (M. tb) is known to downregulate the surface expression of IFN-γ receptor (IFN-γR) on macrophages and peripheral blood mononuclear cells (PBMCs) of patients with active TB disease. Many M. tb antigens also downmodulate IFN-γR levels in macrophages when compared with healthy controls. In the current study, we aimed at deciphering key factors involved in M. tb mediated downregulation of IFN-γR levels on macrophage surface. Our data showed that both M. tb H37Rv and M. bovis BCG infections mediate downmodulation of IFN-γR on human macrophages. This downmodulation is regulated at the level of TLR signaling pathway, second messengers such as calcium and cellular kinases i.e. PKC and ERK-MAPK, indicating that fine tuning of calcium response is critical to maintaining IFN-γR levels on macrophage surface. In addition, genes in the calcium and cysteine protease pathways which were previously identified by us to play a negative role during M. tb infection, also regulated IFN-γR expression. Thus, modulations in IFN-γR levels by utilizing host machinery may be a key immune suppressive strategy adopted by the TB pathogen to ensure its persistence and thwart host defense.

scholarly journals Modulation of Gamma Interferon Receptor 1 by Mycobacterium tuberculosis: a Potential Immune Response Evasive Mechanism

2007 ◽  
Vol 75 (5) ◽  
pp. 2500-2510 ◽  
Author(s):  
Amit Singhal ◽  
Anand Jaiswal ◽  
Virendra K. Arora ◽  
Hanumanthappa K. Prasad
Keyword(s):  
Mycobacterium Tuberculosis ◽  
Mrna Expression ◽  
Mononuclear Cells ◽  
Surface Expression ◽  
Gamma Interferon ◽  
Mobility Shift ◽  
Down Regulation ◽  
Peripheral Blood Mononuclear ◽  
Ifn Γ

ABSTRACT Mycobacterium tuberculosis inhibits gamma interferon (IFN-γ)-mediated antimycobacterial action by adopting diverse mechanisms. IFN-γ binds to its receptor, IFN-γR, in order to initiate proper signaling. We have observed reduced surface expression levels of IFN-γ receptor 1 (IFN-γR1) in untreated pulmonary tuberculosis patients compared to those in healthy individuals (P < 0.01). Following antitubercular therapy, the expression of IFN-γR1 was restored in these patients. To delineate the mechanism by which M. tuberculosis modulates IFN-γR1, in vitro experiments were designed, wherein the down modulation of IFN-γR1 surface expression was observed for CD14+ cells in peripheral blood mononuclear cells (PBMCs) cocultured with live M. tuberculosis compared to that for uninfected cells (P < 0.01). No modulation of IFN-γR1 expression was observed for CD14+ cells in PBMCs infected with Mycobacterium smegmatis. A time-dependent decrease in IFN-γR1 mRNA expression was observed for PBMCs infected with M. tuberculosis. Similar down modulation of IFN-γR1 protein and mRNA expression in phorbol myristate acetate-differentiated THP-1 cells (pdTHP-1) by M. tuberculosis was observed (P < 0.01). Using reporter gene analysis of 5′ deletion constructs of the IFN-γR1 gene (IFNGR1) promoter, the decrease in IFN-γR1 mRNA in M. tuberculosis-infected pdTHP-1 cells was shown to be due to the decreased transcription of IFNGR1. By immunoblotting and electrophoretic mobility shift assays, the down regulation of stimulating protein 1 (Sp1) expression and its recruitment on the phorbol ester-responsive element of the IFNGR1 promoter in M. tuberculosis-infected pdTHP-1 cells was observed. This down regulation of Sp1 in pdTHP-1 cells cocultured with M. tuberculosis may be responsible for the down regulation of IFN-γR1 expression, thereby potentially altering its receptivity to IFN-γ.

scholarly journals Hemodialysis-Related Lymphomononuclear Release of Interleukin-12 in Patients with End-Stage Renal Disease

1999 ◽  
Vol 10 (10) ◽  
pp. 2171-2176 ◽  
Author(s):  
BRUNO MEMOLI ◽  
LUIGI MARZANO ◽  
VINCENZO BISESTI ◽  
MICHELE ANDREUCCI ◽  
BRUNA GUIDA
Keyword(s):  
Mononuclear Cells ◽  
Interferon Γ ◽  
Interleukin 12 ◽  
Control Group ◽  
Peripheral Blood Mononuclear ◽  
Mitogen Stimulation ◽  
Ifn Γ ◽  
Uremic Patients ◽  
Stage Renal Disease ◽  
End Stage

Abstract. Interleukin-12 (IL-12) is a cytokine produced by peripheral blood mononuclear cells (PBMC) that causes interferon-γ (IFN-γ) production and enhancement of cell-mediated cytotoxicity. To clarify the role of hemodialysis biocompatibility on IL-12 production and uremic immunodeficiency, we have studied the IL-12 and IFN-γ release by PBMC harvested from 12 patients dialyzed with cuprophan membrane (CU), eight patients dialyzed with polymethylmethacrylate membrane (PMMA), and eight nondialyzed uremic patients (UR). Ten healthy subjects constituted the control group (CON). PBMC were cultured for 48 h with and without nonspecific mitogen stimulation. In unstimulated conditions, CU showed an IL-12 PBMC production higher than CON, UR, and PMMA (46.67 ± 30.13versus2.56 ± 1.38, 6.16 ± 7.09, and 4.62 ± 4.76 pg/ml, respectively;P< 0.01). IL-12 production was correlated with C3a concentration measured at the outlet of hemodialyzer after 15 min of dialysis (r= 0.69,P< 0.01). IL-12 release in CU remained unchanged under mitogen stimulation (44.34 ± 23.86 pg/ml) and was lower than in CON, UR, and PMMA (66.0 ± 12.41, 68.37 ± 25.78, and 67.75 ± 22.61 pg/ml, respectively;P< 0.05). IFN-γ production was similar, in unstimulated conditions, in all groups. Under stimulation, IFN-γ release was lower in CU (13.42 ± 12.04 IU/ml) than in CON, UR, and PMMA (51.84 ± 30.74, 32.16 ± 13.86, and 32.16 ± 13.86 IU/ml, respectively;P< 0.01). These results demonstrate that hemodialysis with CU induces monocyte activation with an enhanced release of IL-12. On the contrary, stimulated PBMC production of both IL-12 and IFN-γ is lower in these patients than in CON, UR, and PMMA. The altered release of these cytokines could play a role in cell-mediated immunodeficiency of the uremic patients dialyzed with CU.

scholarly journals Spontaneous secretion of interferon γ and interleukin 4 by human intraepithelial and lamina propria gut lymphocytes

Gut ◽  
1998 ◽  
Vol 42 (5) ◽  
pp. 643-649 ◽  
Author(s):  
M Carol ◽  
A Lambrechts ◽  
A Van Gossum ◽  
M Libin ◽  
M Goldman ◽  
...  
Keyword(s):  
Lamina Propria ◽  
Intestinal Mucosa ◽  
Mononuclear Cells ◽  
Critical Role ◽  
Gastrointestinal Diseases ◽  
Interferon Γ ◽  
Interleukin 4 ◽  
Peripheral Blood Mononuclear ◽  
Ifn Γ

Background—Cytokines secreted by intestinal T lymphocytes probably play a critical role in regulation of the gut associated immune responses.Aims—To quantify interferon γ (IFN-γ) and interleukin 4 (IL-4) secreting cells (SC) among human intraepithelial (IEL) and lamina propria (LPL) lymphocytes from the duodenum and right colon in non-pathological situations and in the absence of in vitro stimulation.Patients—Duodenal and right colonic biopsy specimens were obtained from patients with no inflammation of the intestinal mucosa.Methods—Intraepithelial and lamina propria cell suspensions were assayed for numbers of cells spontaneously secreting IFN-γ and IL-4 by a two site reverse enzyme linked immunospot technique (ELISPOT).Results—The relatively high proportion of duodenal lymphocytes spontaneously secreting IFN-γ (IEL 3.6%; LPL 1.9%) and IL-4 (IEL 1.3%; LPL 0.7%) contrasted with the very low numbers of spontaneously IFN-γ SC and the absence of spontaneously IL-4 SC among peripheral blood mononuclear cells. In the basal state, both IFN-γ and IL-4 were mainly produced by CD4+ cells. Within the colon, only 0.2% of IEL and LPL secreted IFN-γ in the basal state, and 0.1% secreted IL-4.Conclusions—Compared with peripheral lymphocytes substantial proportions of intestinal epithelial and lamina propria lymphocytes spontaneously secrete IFN-γ and/or IL-4. These cytokines are probably involved in the normal homoeostasis of the human intestinal mucosa. Disturbances in their secretion could play a role in the pathogenesis of gastrointestinal diseases.

Superantigen immune stimulation activates epithelial STAT-1 and PI 3-K: PI 3-K regulation of permeability

2000 ◽  
Vol 279 (5) ◽  
pp. G1094-G1103 ◽  
Author(s):  
Derek M. McKay ◽  
Fernando Botelho ◽  
Peter J. M. Ceponis ◽  
Carl D. Richards
Keyword(s):  
Epithelial Cells ◽  
Conditioned Medium ◽  
Intracellular Signaling ◽  
Mononuclear Cells ◽  
Interferon Γ ◽  
Transepithelial Resistance ◽  
Mobility Shift ◽  
Peripheral Blood Mononuclear ◽  
Ussing Chambers ◽  
Ifn Γ

Signal transducers and activators of transcription (STATs) are critical intracellular signaling molecules for many cytokines. We compared the ability of T84 epithelial cells to activate STATs in response to cytokines [interferon-γ (IFN-γ), interleukin (IL)-4, IL-10, and tumor necrosis factor-α (10 ng/ml)] and conditioned medium from superantigen [ Staphylococcus aureus enterotoxin B (SEB)]-activated peripheral blood mononuclear cells (PBMC) using electrophoretic mobility shift assays (EMSA). Of the cytokines tested, only IFN-γ caused a STAT-1 response. Exposure to SEB-PBMC-conditioned medium resulted in STAT-1 or STAT-1/3 activation, and inclusion of anti-IFN-γ antibodies in the conditioned medium abolished the STAT-1 signal. Cells treated with transcription factor decoys, DNA oligonucleotides bearing the STAT-1 recognition motif, and then SEB-PBMC-conditioned medium displayed a reduced STAT-1 signal on EMSA, yet this treatment did not prevent the drop in transepithelial resistance (measured in Ussing chambers) caused by SEB-PBMC-conditioned medium. In contrast, the phosphatidylinositol 3′-kinase (PI 3-K) inhibitor LY-294002 significantly reduced the drop in transepithelial resistance caused by SEB-PBMC-conditioned medium. Thus data are presented showing STAT-1 (±STAT-3) and PI 3-K activation in epithelial cells in response to immune mediators released by superantigen immune activation. Although the involvement of STAT-1/-3 in the control of barrier function remains a possibility, PI-3K has been identified as a regulator of T84 paracellular permeability.

scholarly journals Interleukin 12 (IL-12) Is Crucial to the Development of Protective Immunity in Mice Intravenously Infected with Mycobacterium tuberculosis

1997 ◽  
Vol 186 (1) ◽  
pp. 39-45 ◽  
Author(s):  
Andrea M. Cooper ◽  
Jeanne Magram ◽  
Jessica Ferrante ◽  
Ian M. Orme
Keyword(s):  
Immune Response ◽  
Mycobacterium Tuberculosis ◽  
T Cell Activation ◽  
Bacterial Growth ◽  
Cell Activation ◽  
Interferon Γ ◽  
Delayed Type Hypersensitivity ◽  
Interleukin 12 ◽  
Mycobacterium Tuberculosis Infection ◽  
Ifn Γ

Immunity to Mycobacterium tuberculosis infection is associated with the emergence of protective CD4 T cells that secrete cytokines, resulting in activation of macrophages and the recruitment of monocytes to initiate granuloma formation. The cytokine-mediating macrophage activation is interferon-γ (IFN-γ), which is largely dependent on interleukin-12 (IL-12) for its induction. To address the role of IL-12 in immunity to tuberculosis, IL-12 p40−/− mice were infected with M. tuberculosis and their capacity to control bacterial growth and other characteristics of their immune response were determined. The IL-12 p40−/− mice were unable to control bacterial growth and this appeared to be linked to the absence of both innate and acquired sources of IFN-γ. T cell activation as measured by delayed type hypersensitivity and lymphocyte accumulation at the site of infection were both markedly reduced in the IL-12 p40−/− mice. Therefore, IL-12 is essential to the generation of a protective immune response to M. tuberculosis, with its main functions being the induction of the expression of IFN-γ and the activation of antigen-specific lymphocytes capable of creating a protective granuloma.

scholarly journals Low Induction of Proinflammatory Cytokines Parallels Evolutionary Success of Modern Strains within the Mycobacterium tuberculosis Beijing Genotype

2013 ◽  
Vol 81 (10) ◽  
pp. 3750-3756 ◽  
Author(s):  
Arjan van Laarhoven ◽  
Jornt J. Mandemakers ◽  
Johanneke Kleinnijenhuis ◽  
Mimount Enaimi ◽  
Ekta Lachmandas ◽  
...  
Keyword(s):  
Mycobacterium Tuberculosis ◽  
Mononuclear Cells ◽  
Ex Vivo ◽  
Selective Advantage ◽  
Beijing Genotype ◽  
Peripheral Blood Mononuclear ◽  
Content Type ◽  
Tnf Α ◽  
Evolutionary Success ◽  
Ifn Γ

ABSTRACTOne of the most widespread clades ofMycobacterium tuberculosisworldwide, the Beijing genotype family, consists of ancient (atypical) and modern (typical) strains. Modern Beijing strains outcompete ancient strains in terms of prevalence, while reserving a higher degree of genetic conservation. We hypothesize that their selective advantage lies in eliciting a different host immune response. Bead-disrupted lysates of a collection of differentM. tuberculosisstrains of the modern (n= 7) or ancient (n= 7) Beijing genotype, as well as the Euro-American lineage (n= 6), were used for induction ofex vivocytokine production in peripheral blood mononuclear cells (PBMCs) from 10 healthy individuals. Hierarchical clustering and multivariate regression analyses were used to study possible differences in production of nine cytokines. Modern and ancientM. tuberculosisBeijing genotypes induced different cytokine signatures. Overall induction of interleukin-1β (IL-1β), gamma interferon (IFN-γ), and IL-22 was 38 to 40% lower after stimulation with modern Beijing strains (correctedPvalues of <0.0001, 0.0288, and 0.0002, respectively). Euro-American reactivation strains induced 2-fold more TNF-α production than both types of Beijing strains. The observed differences in cytokine induction point to a reduction in proinflammatory cytokine response as a possible contributing factor to the evolutionary success of modern Beijing strains.

scholarly journals 1-Methyl-tryptophan enantiomers differently affect the cross-talking between mononuclear and tumor cells and interferon-γ production

2019 ◽  
Author(s):  
Maryana Stephany Ferreira Branquinho ◽  
Maysa Braga Barros Silva ◽  
Renan Orsati Clara ◽  
Ariane Rivellis Julio ◽  
Silvya Stuchi Maria Engler ◽  
...  
Keyword(s):  
Tumor Cells ◽  
Mononuclear Cells ◽  
Interferon Γ ◽  
Racemic Mixture ◽  
Peripheral Blood Mononuclear ◽  
Tumoricidal Activity ◽  
Tumor Recognition ◽  
Unknown Reason ◽  
Ifn Γ

AbstractThe inhibition of the enzyme indoleamine-2,3-dioxygenase (IDO), that catalyzes the oxidation of the amino acid tryptophan to kynurenine (KYN), is considered a good target for immunoadjuvants in antineoplastic therapy. 1-Methyl-tryptophan (1-MT) is the most studied molecule for this purpose. Although L-1-MT is better than D-1-MT in inhibiting IDO, for an unknown reason the D-enantiomer has higher clinical efficacy. Here we took advantage of co-cultures of tumor cells (SK-Mel 19 melanoma line; 1×105 cells/well) with peripheral blood mononuclear cells (PBMC; 5×106 cells/well) to verify the effect of 1-MT enantiomers on cytokine production and tumoricidal activity. At a concentration that did not affect KYN production, 1-MT (50 µM) affected the production of TNF-α, IL-10, and IFN-γ measured in co-cultures supernatants. Stereospecificity was only observed for IFN-γ production. D-1-MT inhibited more than 30% of IFN-γ production, while L-1-MT had no effect. Stereospecific effect was also seen in PBMC tumoricidal activity, estimated by tumor cell viability (Trypan assay). The racemic mixture DL- and D-1-MT almost doubled the tumoricidal activity of PBMCs, while L-1-MT had no effect. These are previous unknown off-target effects of D-1-MT. Our data suggest the modulation of IFN-γ and the activation of tumor recognition and killing processes by immune cells as important features for the in vivo effects of the D-1-MT. These findings should be considered in future studies of immunoadjuvants for cancer treatment.

scholarly journals Alloimmune Monitoring after Islet Transplantation: A Prospective Multicenter Assessment of 25 Recipients

2016 ◽  
Vol 25 (12) ◽  
pp. 2259-2268 ◽  
Author(s):  
Vaihere Delaune ◽  
Christian Toso ◽  
Pierre-Yves Benhamou ◽  
Anne Wojtusciszyn ◽  
Laurence Kessler ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
Islet Transplantation ◽  
Mononuclear Cells ◽  
Interleukin 2 ◽  
Graft Function ◽  
Area Under The Curve ◽  
Interferon Γ ◽  
Ki 67 ◽  
Peripheral Blood Mononuclear ◽  
Ifn Γ

Islet transplantation is an effective treatment for selected patients with type 1 diabetes. However, an accurate test still lacks for the early detection of graft rejection. Blood samples were prospectively collected in four university centers (Geneva, Grenoble, Montpellier, and Strasbourg). Peripheral blood mononuclear cells were stimulated with donor splenocytes in the presence of interleukin-2. After 24 h of incubation, interferon-γ (IFN-γ) ELISpot analysis was performed. After a total of 5 days of incubation, cell proliferation was assessed by fluorescence-activated cell sorting (FACS) analysis for Ki-67. Immunological events were correlated with adverse metabolic events determined by loss of ≥1 point of β-score and/or an increased insulin intake ≥10%. Twenty-five patients were analyzed; 14 were recipients of islets alone, and 11 combined with kidney. Overall, 76% (19/25) reached insulin independence at one point during a mean follow-up of 30.7 months. IFN-γ ELISpot showed no detectable correlation with adverse metabolic events [area under the curve (AUC) = 0.57]. Similarly, cell proliferation analysis showed no detectable correlation with adverse metabolic events (CD3+/ CD4+ AUC = 0.54; CD3+/CD8+ AUC = 0.55; CD3-/CD56+ AUC = 0.50). CD3-/CD56+ cell proliferation was significantly higher in patients with combined kidney transplantation versus islet alone (6 months, p = 0.010; 12 months, p = 0.016; and 24 months, p = 0.018). Donor antigen-stimulated IFN-γ production and cell proliferation do not predict adverse metabolic events after islet transplantation. This suggests that the volume of transplanted islets is too small to produce a detectable systemic immune response and/or that alloimmune rejection is not the sole reason for the loss of islet graft function.

CD49d provides access to “untouched” human Foxp3+ Treg free of contaminating effector cells

Blood ◽  
2009 ◽  
Vol 113 (4) ◽  
pp. 827-836 ◽  
Author(s):  
Markus Kleinewietfeld ◽  
Mireille Starke ◽  
Diletta Di Mitri ◽  
Giovanna Borsellino ◽  
Luca Battistini ◽  
...  
Keyword(s):  
Mononuclear Cells ◽  
Treg Cells ◽  
Interferon Γ ◽  
Clinical Applications ◽  
Interleukin 17 ◽  
Peripheral Blood Mononuclear ◽  
Effector Cells ◽  
Ifn Γ

Abstract The adoptive transfer of regulatory Foxp3+ T (Treg) cells has been shown in various animal models to prevent inflammatory immune and autoimmune diseases. Translation into therapeutic applications, however, is hindered by the lack of suitable techniques and markers. CD25, commonly used to isolate Treg cells from mice, has only limited value in humans as it is also present on proinflammatory CD4+ effector cells. Here we show that clean populations of human Foxp3+ Treg cells can be obtained with antibodies directed against CD49d. The marker is present on proinflammatory peripheral blood mononuclear cells but is absent on immune-suppressive Treg cells. Depletion with α-CD49d removes contaminating interferon-γ (IFN-γ)– and interleukin-17 (IL-17)–secreting cells from Treg preparations of CD4+CD25high cells. More importantly, in combination with α-CD127 it allows the isolation of “untouched” Foxp3+ Treg (ie, cells that have not been targeted by an antibody during purification). The removal of CD49d+/CD127+ cells leaves a population of Foxp3+ Treg virtually free of contaminating CD25+ effector cells. The cells can be expanded in vitro and are effective suppressors both in vitro and in vivo. Thus, CD49d provides access to highly pure populations of untouched Foxp3+ Treg cells conferring maximal safety for future clinical applications.

scholarly journals Differential Live Mycobacterium tuberculosis-, M. bovis BCG-, Recombinant ESAT6-, and Culture Filtrate Protein 10-Induced Immunity in Tuberculosis

2009 ◽  
Vol 16 (7) ◽  
pp. 991-998 ◽  
Author(s):  
Zahra Hasan ◽  
Bushra Jamil ◽  
Mussarat Ashraf ◽  
Muniba Islam ◽  
Maqboola Dojki ◽  
...  
Keyword(s):  
Mycobacterium Tuberculosis ◽  
Culture Filtrate ◽  
Mononuclear Cells ◽  
Interleukin 10 ◽  
Peripheral Blood Mononuclear ◽  
High Prevalence ◽  
Ifn Γ ◽  
Mycobacterial Antigens ◽  
Induced Immunity ◽  
Culture Filtrate Protein

ABSTRACT The high prevalence of Mycobacterium tuberculosis makes it imperative that immune responses to evaluate could be predictive of infection. We investigated live Mycobacterium- and recombinant antigen-induced cytokine and chemokine responses in patients with active tuberculosis (TB) compared with those of healthy controls from an area where TB is endemic (ECs). M. tuberculosis-, M. bovis BCG-, ESAT6-, and culture filtrate protein 10 (CFP10)-induced responses were determined in peripheral blood mononuclear cells from patients with pulmonary TB (n = 38) and ECs (n = 39). The levels of the cytokines gamma interferon (IFN-γ) and interleukin-10 (IL-10) and the chemokines CCL2, CCL3, and CXCL9 were measured. The levels of M. tuberculosis- and BCG-induced IFN-γ secretion were significantly reduced (P = 0.002 and P < 0.01, respectively), while the amount of IL-10 induced by both virulent (P < 0.01) and avirulent (P = 0.002) mycobacteria was increased in patients with TB. The ESAT6-induced IFN-γ responses were increased in the patients with TB (P = 0.013) compared with those in the EC group. When tuberculin skin test (TST)-negative (TST−; induration, <10 mm) and TST-positive (TST+) donors were studied separately, both TST− and TST+ individuals showed increased IFN-γ responses to M. tuberculosis compared with the responses of the patients with TB (P = 0.037 and P = 0.006, respectively). However, only TST+ ECs showed reduced IFN-γ responses to ESAT6 (P = 0.008) compared with the responses of the patients with TB. The levels of M. tuberculosis-induced CCL2 (P = 0.006) and CXCL9 (P = 0.017) were greater in the patients with TB. The levels of CCL3 secretion in response to Mycobacterium and antigen stimulation were comparable between the two groups. While the levels of ESAT6-induced chemokines did not differ between the patients with TB and the ECs, the levels of CFP10-induced CCL2 (P = 0.01) and CXCL9 (P = 0.001) were increased in the patients. These data indicate differential host IFN-γ, CXCL9, and CCL2 responses to live mycobacteria and mycobacterial antigens and have implications for the identification of potential biomarkers of infection which could be used for the diagnosis of TB.

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