scholarly journals Interferon-γ is a master checkpoint regulator of cytokine-induced differentiation

2017 ◽  
Vol 114 (33) ◽  
pp. E6867-E6874 ◽  
Author(s):  
Zhao Zha ◽  
Felicitas Bucher ◽  
Anahita Nejatfard ◽  
Tianqing Zheng ◽  
Hongkai Zhang ◽  
...  

Cytokines are protein mediators that are known to be involved in many biological processes, including cell growth, survival, inflammation, and development. To study their regulation, we generated a library of 209 different cytokines. This was used in a combinatorial format to study the effects of cytokines on each other, with particular reference to the control of differentiation. This study showed that IFN-γ is a master checkpoint regulator for many cytokines. It operates via an autocrine mechanism to elevate STAT1 and induce internalization of gp130, a common component of many heterodimeric cytokine receptors. This targeting of a receptor subunit that is common to all members of an otherwise diverse family solves the problem of how a master regulator can control so many diverse receptors. When one adds an autocrine mechanism, fine control at the level of individual cells is achieved.

Blood ◽  
1999 ◽  
Vol 93 (11) ◽  
pp. 3900-3912 ◽  
Author(s):  
Fuad Bahram ◽  
Siqin Wu ◽  
Fredrik Öberg ◽  
Bernhard Lüscher ◽  
Lars-Gunnar Larsson

The transcription factors of the Myc/Max/Mad network are important regulators of cell growth, differentiation, and apoptosis and are frequently involved in tumor development. Constitutive expression of v-Myc blocks phorbol ester (TPA)-induced differentiation of human U-937 monoblasts. However, costimulation with interferon-γ (IFN-γ) and TPA restores terminal differentiation and G1cell-cycle arrest despite continuous expression of v-Myc. The mechanism by which TPA + IFN-γ counteract v-Myc activity has not been unravelled. Our results show that TPA + IFN-γ treatment led to an inhibition of v-Myc– and c-Myc–dependent transcription, and a specific reduction of v-Myc:Max complexes and associated DNA-binding activity, whereas the steady state level of the v-Myc protein was only marginally affected. In contrast, TPA + IFN-γ costimulation neither increased the expression of Mad1 or other mad/mnt family genes nor altered heterodimerization or DNA-binding activity of Mad1. The reduced amount of v-Myc:Max heterodimers in response to treatment was accompanied by partial dephosphorylation of v-Myc and c-Myc. Phosphatase treatment of Myc:Max complexes lead to their dissociation, thus mimicking the effect of TPA + IFN-γ. In addition to modulation of the expression of Myc/Max/Mad network proteins, posttranslational negative regulation of Myc by external signals may, therefore, be an alternative biologically important level of control with potential therapeutic relevance for hematopoietic and other tumors with deregulated Myc expression.


Blood ◽  
1999 ◽  
Vol 93 (11) ◽  
pp. 3900-3912 ◽  
Author(s):  
Fuad Bahram ◽  
Siqin Wu ◽  
Fredrik Öberg ◽  
Bernhard Lüscher ◽  
Lars-Gunnar Larsson

Abstract The transcription factors of the Myc/Max/Mad network are important regulators of cell growth, differentiation, and apoptosis and are frequently involved in tumor development. Constitutive expression of v-Myc blocks phorbol ester (TPA)-induced differentiation of human U-937 monoblasts. However, costimulation with interferon-γ (IFN-γ) and TPA restores terminal differentiation and G1cell-cycle arrest despite continuous expression of v-Myc. The mechanism by which TPA + IFN-γ counteract v-Myc activity has not been unravelled. Our results show that TPA + IFN-γ treatment led to an inhibition of v-Myc– and c-Myc–dependent transcription, and a specific reduction of v-Myc:Max complexes and associated DNA-binding activity, whereas the steady state level of the v-Myc protein was only marginally affected. In contrast, TPA + IFN-γ costimulation neither increased the expression of Mad1 or other mad/mnt family genes nor altered heterodimerization or DNA-binding activity of Mad1. The reduced amount of v-Myc:Max heterodimers in response to treatment was accompanied by partial dephosphorylation of v-Myc and c-Myc. Phosphatase treatment of Myc:Max complexes lead to their dissociation, thus mimicking the effect of TPA + IFN-γ. In addition to modulation of the expression of Myc/Max/Mad network proteins, posttranslational negative regulation of Myc by external signals may, therefore, be an alternative biologically important level of control with potential therapeutic relevance for hematopoietic and other tumors with deregulated Myc expression.


1997 ◽  
Vol 273 (6) ◽  
pp. C2030-C2036 ◽  
Author(s):  
Sean Meehan ◽  
Ava J. Wu ◽  
Elaine C. Kang ◽  
Takayuki Sakai ◽  
Indu S. Ambudkar

Interferon-γ (IFN-γ) ± tumor necrosis factor-α (TNF-α) induces antiproliferation and intracellular Ca2+ store depletion in a human submandibular ductal cell line (HSG), which can be reversed on cytokine removal [A. J. Wu, G. C. Chen, B. J. Baum, and I. S. Ambudkar. Am. J. Physiol. 270 ( Cell Physiol. 39): C514–C521, 1996]. Here we have examined a possible mechanism for the IFN-γ-induced intracellular Ca2+store depletion. There was a time-dependent decrease in thapsigargin-dependent internal Ca2+ release after exposure of the cells to the cytokines. The intracellular Ca2+ pump [sarco(endo)plasmic reticulum Ca2+-ATPase (SERCA)] protein in lysates and membranes of cells treated with IFN-γ ± TNF-α, but not with TNF-α alone, showed a similar time-dependent decrease (examined using a SERCA2 antibody). Removal of the cytokines, which resulted in recovery of cell growth and refill of internal Ca2+ stores, also increased the level of SERCA protein. The decrease in SERCA is not a result of decreased cell proliferation, since thapsigargin, 2,5-di-( t-butyl)-1,4-hydroquinone, or serum-free growth conditions induced antiproliferative effects on HSG cells without any corresponding decrease in SERCA. We suggest that the IFN-γ-induced decrease in the level of SERCA accounts for the depleted state of internal Ca2+stores in cytokine-treated HSG cells. These data suggest a novel mechanism for the inhibition of HSG cell growth by IFN-γ.


2019 ◽  
Vol 71 (1) ◽  
pp. 53-62 ◽  
Author(s):  
Gloria H Hong ◽  
Ana M Ortega-Villa ◽  
Sally Hunsberger ◽  
Ploenchan Chetchotisakd ◽  
Siriluck Anunnatsiri ◽  
...  

Abstract Background The natural history of anti-interferon-γ (IFN-γ) autoantibody-associated immunodeficiency syndrome is not well understood. Methods Data of 74 patients with anti-IFN-γ autoantibodies at Srinagarind Hospital, Thailand, were collected annually (median follow-up duration, 7.5 years). Annual data for 19 patients and initial data for 4 patients with anti-IFN-γ autoantibodies at the US National Institutes of Health were collected (median follow-up duration, 4.5 years). Anti-IFN-γ autoantibody levels were measured in plasma samples. Results Ninety-one percent of US patients were of Southeast Asian descent; there was a stronger female predominance (91%) in US than Thai (64%) patients. Mycobacterium abscessus (34%) and Mycobacterium avium complex (83%) were the most common nontuberculous mycobacteria in Thailand and the United States, respectively. Skin infections were more common in Thailand (P = .001), whereas bone (P < .0001), lung (P = .002), and central nervous system (P = .03) infections were more common in the United States. Twenty-four percent of Thai patients died, most from infections. None of the 19 US patients with follow-up data died. Anti-IFN-γ autoantibody levels decreased over time in Thailand (P < .001) and the United States (P = .017), with either cyclophosphamide (P = .01) or rituximab therapy (P = .001). Conclusions Patients with anti-IFN-γ autoantibodies in Thailand and the United States had distinct demographic and clinical features. While titers generally decreased with time, anti-IFN-γ autoantibody disease had a chronic clinical course with persistent infections and death. Close long-term surveillance for new infections is recommended.


Pathogens ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 757
Author(s):  
Sandra Barroso-Arévalo ◽  
Jose A. Barasona ◽  
Estefanía Cadenas-Fernández ◽  
José M. Sánchez-Vizcaíno

African swine fever virus (ASFv) is one of the most challenging pathogens to affect both domestic and wild pigs. The disease has now spread to Europe and Asia, causing great damage to the pig industry. Although no commercial vaccine with which to control the disease is, as yet, available, some potential vaccine candidates have shown good results in terms of protection. However, little is known about the host immune mechanisms underlying that protection, especially in wild boar, which is the main reservoir of the disease in Europe. Here, we study the role played by two cytokines (IL-10 and IFN-γ) in wild boar orally inoculated with the attenuated vaccine candidate Lv17/WB/Rie1 and challenged with a virulent ASFv genotype II isolate. A group of naïve wild boar challenged with the latter isolate was also established as a control group. Our results showed that both cytokines play a key role in protecting the host against the challenge virus. While high levels of IL-10 in serum may trigger an immune system malfunctioning in challenged animals, the provision of stable levels of this cytokine over time may help to control the disease. This, together with high and timely induction of IFN-γ by the vaccine candidate, could help protect animals from fatal outcomes. Further studies should be conducted in order to support these preliminary results and confirm the role of these two cytokines as potential markers of the evolution of ASFV infection.


2020 ◽  
Vol 79 (Suppl 1) ◽  
pp. 238.1-238
Author(s):  
Y. Shimojima ◽  
D. Kishida ◽  
T. Ichikawa ◽  
Y. Sekijima

Background:In the acute phase of adult-onset Still’s disease (AOSD), elevated levels of proinflammatory cytokines including interferon-γ (IFN-γ) are shown. Moreover, IFN-γ impacts on activating macrophages which play a crucial role in the pathogenesis of AOSD. Natural killer (NK) cells and T helper cells are in charge of secreting IFN-γ in the innate and adaptive immune systems of disease, respectively. However, the features of their IFN-γ-producing variation depending on disease activity are still uncertain in AOSD.Objectives:We investigated characteristics of IFN-γ-producing CD4+T cells and NK cells in patients with AOSD.Methods:Twenty-four patients in the acute phase of AOSD (active AOSD), 8 of them after treatment (remission), and 12 healthy controls (HC) were recruited in this study. Peripheral blood mononuclear cells and serum samples were provided from them for the experimental analysis. Flow cytometry was used for analyzing CD4+T cells, CD4+regulatory T cells (Tregs), NK cells, and their intracellular IFN-γ expression levels as well as suppression assay of Tregs. The serum concentration of interleukin-18 (IL-18) was measured using commercially available ELISA kit. Relationship between the analyzed data and clinical findings related to disease activity were statistically evaluated.Results:IFN-γ expression in CD4+T cells was significantly higher in active AOSD than in HC (p < 0.05). Tregs also significantly indicated higher expression of IFN-γ in active AOSD than in HC (p < 0.0001); and moreover, Tregs were significantly impaired in their suppression ability (p < 0.05). In both CD4+T cells and Tregs, expression of IFN-γ was significantly correlated with serum ferritin levels in active AOSD (p < 0.05). IFN-γ expression in CD4+T cells was significantly higher in patients with splenomegaly than those without that (p < 0.05). The proportion of NK cells was significantly lower in active AOSD than in HC (p < 0.005), whereas IFN-γ expression in NK cells was significantly higher in active AOSD than in HC (p < 0.0005). The number of NK cells and IFN-γ-expressing NK cells had inverse relationship with serum ferritin levels in active AOSD (p < 0.05 and p < 0.005, respectively). Increased number of NK cells and their decreased expression of IFN-γ were significantly demonstrated in remission (p < 0.05). In the analyses of NK cell subsets, lower expression of IFN-γ in CD56brightNK cells and higher that in CD56dimNK cells were significantly indicated in active AOSD than HC (p < 0.05). In remission, IFN-γ expression was significantly decreased in CD56dimNK cells (p < 0.05) despite no significant recovery of that in CD56brightNK cells (p = 0.311). Meanwhile, increased expression of IFN-γ in CD56brightNK cells was demonstrated in only patients who were treated with biologics. Although serum levels of IL-18 were significantly higher in active AOSD than in remission and HC; however, they had no significant correlations with any analyzed data.Conclusion:CD4+T cells and NK cells promote IFN-γ expression in the acute phase of AOSD. Meanwhile, increased expression of IFN-γ in CD4+T cells and decreased number of NK cells were correlated with serum ferritin levels, suggesting that they are indicators of disease activity. Furthermore, high disease activity may impact on the alteration of IFN-γ-producing balance in two distinct population of NK cells, and the plasticity of Tregs leading to defect in suppression ability.Disclosure of Interests:None declared


1985 ◽  
Vol 7 (3) ◽  
pp. 327
Author(s):  
F. Velotti ◽  
A. Santoni ◽  
F. Cofano ◽  
S. Landolfo ◽  
M. Piccoli ◽  
...  

2013 ◽  
Vol 34 (6) ◽  
pp. 619-624 ◽  
Author(s):  
Antonino Catanzaro ◽  
Charles Daley

Studies over the past several decades have dramatically increased our understanding of the immune response to Mycobacterium tuberculosis infection, and advances in proteomics and genomics have led to a new class of immune-diagnostic tests, termed interferon-γ (IFN-γ) release assays (IGRAs), which appear to obviate many of the problems encountered with the tuberculin skin test (TST). Worldwide, 2 IGRAs are currently commercially available. QuantiFERON-TB Gold In-Tube (Cellestis) is a third-generation product that uses an enzyme-linked immunosorbent assay to measure IFN-γ generated in whole blood stimulated with M. tuberculosis–specific antigens. T-Spot-TB (Oxford Immunotec) employs enzyme-linked immunosorbent spot technology to enumerate the number of purified lymphocytes that respond to M. tuberculosis–specific antigens by producing IFN-γ. These in vitro tests measure the host immune response to M. tuberculosis–specific antigens, which virtually eliminates false-positive cross reactions caused by bacillus Calmette-Guérin vaccination and/or exposure to environmental nontuberculous mycobacteria that plague the interpretation and accuracy of the tuberculin skin test (TST). The high specificity of IGRAs, together with sensitivity commensurate with or better than that of the TST, promises an accurate diagnosis and the ability to focus tuberculosis-control activities on those who are actually infected with M. tuberculosis. The Third Global Symposium was held over a 3-day period and was presented by the University of California, San Diego, Continuing Medical Education department; slides and sound recordings of each presentation are available at http://cme.ucsd.edu/igras/syllabus.html. A moderated discussion is also available at http://cme.ucsd.edu/igrasvideo. This document provides a summary of the key findings of the meeting, specifically focusing on the use of IGRAs in screening healthcare worker populations.


2003 ◽  
Vol 197 (2) ◽  
pp. 169-179 ◽  
Author(s):  
Courtney Beers ◽  
Karen Honey ◽  
Susan Fink ◽  
Katherine Forbush ◽  
Alexander Rudensky

Cathepsin S (catS) and cathepsin L (catL) mediate late stages of invariant chain (Ii) degradation in discrete antigen-presenting cell types. Macrophages (Mϕs) are unique in that they express both proteases and here we sought to determine the relative contribution of each enzyme. We observe that catL plays no significant role in Ii cleavage in interferon (IFN)-γ–stimulated Mϕs. In addition, our studies show that the level of catL activity is significantly decreased in Mϕs cultured in the presence of IFN-γ whereas catS activity increases. The decrease in catL activity upon cytokine treatment occurs despite the persistence of high levels of mature catL protein, suggesting that a specific inhibitor of the enzyme is up-regulated in IFN-γ–stimulated peritoneal Mϕs. Similar inhibition of activity is observed in dendritic cells engineered to overexpress catL. Such enzymatic inhibition in Mϕs exhibits only partial dependence upon Ii and therefore, other mechanisms of catL inhibition are regulated by IFN-γ. Thus, during a T helper cell type 1 immune response catL inhibition in Mϕs results in preferential usage of catS, such that major histocompatibility complex class II presentation by all bone marrow–derived antigen-presenting cell is regulated by catS.


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