The aryl hydrocarbon receptor and interferon gamma generate antiviral states via transcriptional repression

The aryl hydrocarbon receptor (AhR) is a ligand-dependent transcription factor whose activation induces the expression of numerous genes, with many effects on cells. However, AhR activation is not known to affect the replication of viruses. We show that AhR activation in macrophages causes a block to HIV-1 and HSV-1 replication. We find that AhR activation transcriptionally represses cyclin-dependent kinase (CDK)1/2 and their associated cyclins, thereby reducing SAMHD1 phosphorylation, cellular dNTP levels and both HIV-1 and HSV-1 replication. Remarkably, a different antiviral stimulus, interferon gamma (IFN-γ), that induces a largely non-overlapping set of genes, also transcriptionally represses CDK1, CDK2 and their associated cyclins, resulting in similar dNTP depletion and antiviral effects. Concordantly, the SIV Vpx protein provides complete and partial resistance to the antiviral effects of AhR and IFN-γ, respectively. Thus, distinct antiviral signaling pathways converge on CDK/cyclin repression, causing inhibition of viral DNA synthesis and replication.

The Role of Interferon-Gamma in Hematopoietic Stem Cell Development, Homeostasis, and Disease

Purpose of Review

Interferon-gamma (IFN-γ) is a pro-inflammatory cytokine that participates in the regulation of hematopoietic stem cells (HSC) during development and under homeostatic conditions. IFN-γ also plays a key pathogenic role in several diseases that affect hematopoiesis including aplastic anemia, hemophagocytic lymphohistiocytosis, and cirrhosis of the liver.

Recent Findings

Studies have shown that increased IFN-γ negatively affects HSC homeostasis, skewing HSC towards differentiation over self-renewal and eventually causing exhaustion of the HSC compartment.

Summary

Here, we explore the mechanisms by which IFN-γ regulates HSC in both normal and pathological conditions. We focus on the role of IFN-γ signaling in HSC fate decisions, and the transcriptional changes it elicits. Elucidating the mechanisms through which IFN-γ regulates HSCs may lead to new therapeutic options to prevent or treat adverse hematologic effects of the many diseases to which IFN-γ contributes.

An IFNγ/CXCL2 regulatory pathway determines lesion localization during EAE

Background

Myelin oligodendrocyte glycoprotein (MOG)-reactive T-helper (Th)1 cells induce conventional experimental autoimmune encephalomyelitis (cEAE), characterized by ascending paralysis and monocyte-predominant spinal cord infiltrates, in C57BL/6 wildtype (WT) hosts. The same T cells induce an atypical form of EAE (aEAE), characterized by ataxia and neutrophil-predominant brainstem infiltrates, in syngeneic IFNγ receptor (IFNγR)-deficient hosts. Production of ELR+ CXC chemokines within the CNS is required for the development of aEAE, but not cEAE. The cellular source(s) and localization of ELR+ CXC chemokines in the CNS and the IFNγ-dependent pathways that regulate their production remain to be elucidated.

Methods

The spatial distribution of inflammatory lesions and CNS expression of the ELR+ CXC chemokines, CXCL1 and CXCL2, were determined via immunohistochemistry and/or in situ hybridization. Levels of CXCL1 and CXCL2, and their cognate receptor CXCR2, were measured in/on leukocyte subsets by flow cytometric and quantitative PCR (qPCR) analysis. Bone marrow neutrophils and macrophages were cultured with inflammatory stimuli in vitro prior to measurement of CXCL2 and CXCR2 by qPCR or flow cytometry.

Results

CNS-infiltrating neutrophils and monocytes, and resident microglia, are a prominent source of CXCL2 in the brainstem of IFNγRKO adoptive transfer recipients during aEAE. In WT transfer recipients, IFNγ directly suppresses CXCL2 transcription in microglia and myeloid cells, and CXCR2 transcription in CNS-infiltrating neutrophils. Consequently, infiltration of the brainstem parenchyma from the adjacent meninges is blocked during cEAE. CXCL2 directly stimulates its own expression in cultured neutrophils, which is enhanced by IL-1 and suppressed by IFNγ.

Conclusions

We provide evidence for an IFNγ-regulated CXCR2/CXCL2 autocrine/paracrine feedback loop in innate immune cells that determines the location of CNS infiltrates during Th1-mediated EAE. When IFNγ signaling is impaired, myeloid cell production of CXCL2 increases, which promotes brainstem inflammation and results in clinical ataxia. IFNγ, produced within the CNS of WT recipients, suppresses myeloid cell CXCR2 and CXCL2 production, thereby skewing the location of neuroinflammatory infiltrates to the spinal cord and the clinical phenotype to an ascending paralysis. These data reveal a novel mechanism by which IFNγ and CXCL2 interact to direct regional recruitment of leukocytes in the CNS, resulting in distinct clinical presentations.

Electronic supplementary material

The online version of this article (10.1186/s12974-018-1237-y) contains supplementary material, which is available to authorized users.

Developmental expression profiles and thyroidal regulation of cytokines during metamorphosis in the amphibian Xenopus laevis

Early life-stages of amphibians rely on the innate immune system for defense against pathogens. While thyroid hormones (TH) are critical for metamorphosis and later development of the adaptive immune system, the role of TH in innate immune system development is less clear. An integral part of the innate immune response are pro-inflammatory cytokines - effector molecules that allow communication between components of the immune system. The objective of this study was to characterize the expression of key pro-inflammatory cytokines, tumor necrosis factor-α (TNFα), interleukin-1β (IL-1β) and interferon-γ (IFN-γ), throughout amphibian development and determine the impacts of thyroidal modulation on their expression. Xenopus laevis were sampled at various stages of development encompassing early embryogenesis to late prometamorphosis and cytokine expression was measured by real-time PCR. Expression of TNFα and IL-1β were transient over development, increasing with developmental stage, while IFN-γ remained relatively stable. Functionally athyroid, premetamorphic tadpoles were exposed to thyroxine (0.5 and 2 μg/L) or sodium perchlorate (125 and 500 μg/L) for seven days. Tadpoles demonstrated characteristic responses of advanced development with thyroxine exposure and delayed development (although to a lesser extent) and increased thyroid gland area and follicular cell height with sodium perchlorate exposure. Exposure to thyroxine for two days resulted in decreased expression of IL-1β in tadpole trunks. Sodium perchlorate had negligible effects on cytokine expression. Overall, these results demonstrate that cytokine transcript levels vary with stage of tadpole development but that their ontogenic regulation is not likely exclusively influenced by thyroid status. Understanding the direct and indirect effects of altered hormone status may provide insight into potential mechanisms of altered immune function during amphibian development.

Interferon-γ induces biphasic changes in caldesmon localization as well as adherens junction organization and expression in HUVECs

Endothelial barrier dysfunction leads to increased endothelial permeability and is an early step in the development of vascular inflammatory diseases such as atherosclerosis. Interferon-γ (IFN-γ), a proinflammatory cytokine, is known to cause increased endothelial permeability. However, the mechanisms by which IFN-γ disrupts the endothelial barrier have not been clarified. This study aimed to investigate how IFN-γ impairs the endothelial barrier integrity by specifically examining the roles of caldesmon, adherens junctions (AJs) and p38 mitogen-activated protein (MAP) kinase in IFN-γ-induced endothelial barrier dysfunction. IFN-γ exhibited a biphasic effect on caldesmon localization and both the structural organization and protein expression of AJs. In the early phase (4-8 h), IFN-γ induced the formation of peripheral caldesmon bands and discontinuous AJs, while AJ protein expression was unchanged. Interestingly, IFN-γ also stimulated caldesmon phosphorylation, resulting in actin dissociation from caldesmon at 8 h. Conversely, changes seen in the late phase (16-24 h) included cytoplasmic caldesmon dispersal, AJ linearization and junctional area reduction, which were associated with reduced membrane, cytoskeletal and total AJ protein expression. In addition, IFN-γ enhanced myosin binding to caldesmon at 12 h and persisted up to 24 h. Furthermore, inhibition of p38 MAP kinase by SB203580 did not reverse either the early or late phase changes observed. These data suggest that IFN-γ may activate signaling molecules other than p38 MAP kinase. In conclusion, our findings enhance the current understanding of how IFN-γ disrupts endothelial barrier function and reveal potential therapeutic targets, such as caldesmon and AJs, for the treatment of IFN-γ-associated vascular inflammatory diseases.

Equine mesenchymal stromal cells from different tissue sources display comparable immune-related gene expression profiles in response to interferon gamma (IFN)-γ

Mesenchymal stromal cells (MSC) have the therapeutic potential to decrease inflammation due to their immunomodulatory properties. They can be isolated from various tissue sources such as bone marrow, adipose tissue, and blood, but it is unknown how the tissue source of origin affects the responses of MSC to inflammatory stimuli. Here, we conceptually addressed this question by evaluating the immune-related gene expression profiles of equine MSC from different tissue sources in response to interferon gamma (IFN-γ) stimulation, with the goal to determine if there is a preferable MSC source for clinical application in an inflammatory environment. The salient findings from this initial study were that the baseline expression of all immune related genes analyzed, with the exception of prostaglandin-endoperoxide synthase 2 (PTGS2), was variable in MSC depending on tissue source. Following IFN-γ stimulation, however, gene expression profiles became more similar across all tissue sources, suggesting that MSC from different sources will likely respond similarly in an inflammatory environment when used clinically.

The influence of hypoxia and IFN-γ on the proteome and metabolome of therapeutic mesenchymal stem cells

Over the past 15 years, mesenchymal stem cells (MSCs) have been assessed for their capacity to suppress inflammation and promote tissue repair. Regardless of whether the cells are primed (exposed to instructive cues) before administration, their phenotype will respond to environmental signals present in the pathophysiological setting being treated. Since hypoxia and inflammation coexist in the settings of acute injury and chronic disease we sought to explore how the proteome and metabolome of MSCs changes when cells were exposed to 48 h of 1% oxygen, interferon gamma (IFN-γ), or both cues together. We specifically focused on changes in cell metabolism, immune modulation, extracellular matrix secretion and modification, and survival capacity. IFN-γ promoted expression of anti-pathogenic proteins and induced MSCs to limit inflammation and fibrosis while promoting their own survival. Hypoxia instead led to cell adaptation to low oxygen, including upregulation of proteins involved in anaerobic metabolism, autophagy, angiogenesis, and cell migration. While dual priming resulted in additive effects, we also found many instances of synergy. These data lend insight to how MSCs may behave after administration to a patient and suggest how priming cells beforehand could improve their therapeutic capacity.

Comparative Effect of the I3.1 Probiotic Formula in Two Animal Models of Colitis

Use of probiotic therapy is an active area of investigation to treat intestinal disorders. The clinical benefits of the I3.1 probiotic formula (Lactobacillus plantarum (CECT7484, CECT7485) and P. acidilactici (CECT7483)) were demonstrated in irritable bowel syndrome (IBS) patients in a randomized, double-blind, placebo-controlled clinical trial. The aim of this study was to evaluate the therapeutic effects of I3.1 in two experimental models of colitis, a dextran sulfate sodium (DSS)-induced colitis model and an interleukin (IL)-10-deficient mice model. Colitis was induced in 32 8-week-old Balb/c mice by administering 3% (w/v) DSS in drinking water for 5 days. Probiotics were administered orally (I3.1 or VSL#3, 1 × 10⁹ CFU daily) for 10 days before the administration of DSS. Also, probiotics (I3.1 or VSL#3, 1 × 10⁹ CFU daily) were administered orally to 36 6-week-old C57B6J IL-10(-/-) mice for 10 weeks. Body weight was recorded daily. Colon samples were harvested for histological examination and cytokine measurements. Body weight after DSS administration did not change in the I3.1 group, whereas the VSL#3 group had weight loss. Also, I3.1 normalized IL-6 to levels similar to that of healthy controls and significantly increased the reparative histologic score. In the IL-10-deficient model, both VSL#3 and I3.1 reduced the severity of colitis compared to untreated controls, and I3.1 significantly reduced the levels of IFN-γ compared to the other two groups. In conclusion, I3.1 displays a protective effect on two murine models of experimental colitis. Results suggest that the mechanism of action could be different from VSL#3.

Interferon-γ and CXCL10 responses related to complaints in patients with Q fever fatigue syndrome

Approximately 20% of patients with acute Q fever develop Q fever fatigue syndrome (QFS), a debilitating fatigue syndrome. This study further investigates the role of C. burnetii-specific IFNγ, but also IL-2, CXCL9, CXCL10, and CXLC11 production in QFS patients. C. burnetii-specific IFNy, IL-2, CXCL9, CXCL10, and CXCL11 production were tested in ex vivo stimulated whole blood of QFS patients who recovered from their complaints (n = 8), QFS patients with persisting complaints (n = 27), and asymptomatic Q fever seropositive controls (n = 10). With the exclusion of one outlier, stimulation with C. burnetii revealed significantly higher IFNy and CXCL10 production in QFS patients with persisting complaints (medians 288.0 and 176.0 pg/mL, respectively) than in QFS patients who recovered from their complaints (medians 93.0 and 85.5 pg/mL, respectively) (p = 0.041 and 0.045, respectively). No significant differences between groups were found for C. burnetii-specific IL-2, CXCL9, and CXCL11 production. These findings point towards a difference in cell-mediated immunity in QFS patients with persisting complaints compared to those who recovered from their complaints. Such a difference may aid to eventually diagnose QFS more objectively and might serve as an indicator of its underlying etiology.

Analysis of spontaneous resolution of cytomegalovirus replication after transplantation in CMV-seropositive patients with pretransplant CD8+IFNG+ response

This prospective study evaluates whether CMV-seropositive (R+) transplant patients with pretransplant CD8+IFNG+ T-cell response to cytomegalovirus (CMV) (CD8+IFNG+ response) can spontaneously clear the CMV viral load without requiring treatment. A total of 104 transplant patients (kidney/liver) with pretransplant CD8+IFNG+ response were evaluable. This response was determined using QuantiFERON-CMV assay. The incidence of CMV replication and disease was 45.2% (47/104) and 6.7% (7/104), respectively. Of the total patients, 77.9% (81/104) did not require antiviral treatment, either because they did not have CMV replication (n = 57) or because they had asymptomatic CMV replication that could be spontaneously cleared (n = 24). Both situations are likely related to the presence of CD8+IFNG+ response to CMV, which has a key role in controlling CMV infection. However, 22.1% of the patients (23/104) received antiviral treatment, although only 7 of them did so because they had symptomatic CMV replication. These patients developed symptoms in spite of having pretransplant CD8+IFNG+ response, thus suggesting that other immunological parameters might be involved, such as a dysfunctional CD4⁺ response or that they might have become QFNon-reactive due to the immunosuppression. In conclusion, around 80% of R+ patients with pretransplant CD8+IFNG+ response to CMV did not require antiviral treatment, although this percentage might be underestimated. Nevertheless, other strategies such as performing an additional CD8+IFNG+ response determination at posttransplant time might provide more reliable information regarding the patients who will be able to spontaneously clear the viremia.

Targeted therapy or immunotherapy? Optimal treatment in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the fifth leading cause of cancer mortality in the United States and the second leading cause of cancer mortality worldwide. Sorafenib is the only food and drug administration (FDA) approved as first line systemic treatment in HCC. Regorafenib and nivolumab are the only FDA approved second line treatment after progression on sorafenib. We will discuss all potential first and second line options in HCC. In addition, we also will explore sequencing treatment options in HCC, and examine biomarkers that can potentially predict benefits from treatments such as immune checkpoint inhibitor. This minireview summarizes potential treatments in HCC based on clinical trials that have been published in manuscript or abstract format from 1994-2018.

Reduction of MHC-I expression limits T-lymphocyte-mediated killing of Cancer-initiating cells

Background

It has been proposed that cancer establishment, maintenance, and recurrence may be attributed to a unique population of tumor cells termed cancer-initiating cells (CICs) that may include characteristics of putative cancer stem cell-like cells. Studies in lung cancer have shown that such cells can be enriched and propagated in vitro by culturing tumor cells in serum-free suspension as tumorspheres. CICs have been characterized for their phenotype, stem cell-like qualities, and their role in establishing tumor and maintaining tumor growth. Less is known about the interaction of CICs with the immune system.

Methods

We established CIC-enriched tumorspheres from murine TC-1 lung cancer cells, expressing human papillomavirus 16 (HPV-16) E6/E7 antigens, and evaluated their susceptibility to antitumor immune responses both in vitro and in vivo.

Results

TC-1 CICs demonstrated reduced expression of surface major histocompatibility complex (MHC)-I molecules compared to non-CICs. We similarly determined decreased MHC-I expression in five of six human lung cancer cell lines cultured under conditions enriching for CICs. In vivo, TC-1 cells enriched for CICs were resistant to human papillomavirus 16 E6/E7 peptide vaccine-mediated killing. We found that vaccinated mice challenged with CIC enriched tumorspheres demonstrated shorter survivals and showed significantly fewer CD8⁺ tumor infiltrating lymphocytes compared to CIC non-enriched challenged mice. Furthermore, cultured cytotoxic T lymphocytes (CTLs) from vaccinated mice demonstrated reduced capacity to lyse TC-1 cells enriched for CICs compared to non-enriched TC-1 cells. Following treatment with IFN-γ, both CIC enriched and non-enriched TC-1 cells expressed similar levels of MHC-I, and the increased MHC-I expression on CICs resulted in greater CTL-mediated tumor lysis and improved tumor-free survival in mice.

Conclusions

These results suggest that the attenuated expression of MHC-I molecules by CICs represents a potential strategy of CICs to escape immune recognition, and that the development of successful immunotherapy strategies targeting CICs may decrease their resistance to T cell-mediated immune detection by enhancing CIC MHC-I expression.

Electronic supplementary material

The online version of this article (10.1186/s12885-018-4389-3) contains supplementary material, which is available to authorized users.

Quantification of NK cell activity using whole blood: Methodological aspects of a new test

Natural Killer (NK) cells are essential in the biological fight against cancer and intracellular pathogens, and their level of activity has in many settings been used as a biomarker for a functional immune response. Currently, NK cell activity is measured using either ⁵¹Cr-release assays or flow cytometry based assays revealing the cells´ cytotoxic capacity or by stimulating them to produce cytokines. Although very effective, these are cumbersome techniques not suitable for high volume clinical laboratories. Recently, an assay has been introduced to measure NK cell activity in a simple and standardized manner. Following stimulation of NK cells in whole blood with a recombinant protein, it utilizes the concentration of IFNγ released to the plasma as a surrogate marker for NK cell activity. However, whole blood holds several sources of IFNγ which may blur the results and hamper the interpretation of the test. Therefore, the present study aimed at analyzing how specifically the test is measuring the activity of NK cells. Intracellular flow cytometry showed that NK cells, T cells, and Natural Killer T (NKT) cells were producing IFNγ in the assay, however when analyzing the distribution of lymphocytes in the IFNγ-expressing subset, the proportion of NK cells far exceeded the percentage of T-, and NKT cells (p < .0001). Hence, our data indicate that the readout of the test was indicative of the NK cells´ ability to mount a response and thus the results may pave the way for the assay to become applicable in the clinical setting as an estimate of NK cell activity for both diagnostic and prognostic purposes.

The tolerogenic role of IFN-γ

Due to its extremely pleiotropic nature, the complex effects of IFN-γ exerted both on immune and non-immune cell types still remain only partially understood. The longstanding view of IFN-γ as being a predominantly inflammatory cytokine is constantly challenged by increasing demonstrations of its direct or indirect regulatory roles. Interferon-γ can exert tolerogenic effects on both innate and adaptive immune cell types, promoting tolerance of various antigen-presenting cells, and augmenting function and differentiation of regulatory T cells, respectively. Its capacity to induce IDO-competence is not limited to immune cells but extends to other cell types such as mesenchymal stem cells, epithelial cells, and tumors. The pro-inflammatory role of IFN-γ in tumor immune surveillance can backfire by directly inducing inhibitory molecule expression, such as PDL-1, on tumor cells. With increasing knowledge regarding the role of different helper T cell subsets in certain autoimmune diseases, the once contradictory observations of disease attenuation by IFN-γ can now be explained by its opposing interplay with other effector cytokines, particularly IL-17. The paradoxically immunosuppressive role of IFN-γ is also becoming evident in the transplantation setting, and graft-versus-host-disease. In the present review, we will discuss the latest findings that help to elucidate this dual role of IFN-γ at a cellular level, and in various pathophysiological states.

Autoimmune hepatitis association with single nucleotide polymorphism of interleukin-2, but not interferon-gamma

BACKGROUND

Autoimmune hepatitis (AIH) is a chronic inflammation in hepatocellular tissues associated with circulating autoantibodies. Imbalance in T-cells population and dysregulation in several cytokine profiles has been implicated in pathogenesis of AIH. This study was performed to assess potential association of AIH with interleukin-2 (IL-2) and interferon-gamma (IFN-γ) genes single nucleotide polymorphisms (SNPs).

METHODS

Fifty-six patients with AIH and 139 healthy individuals were enrolled in this study. IL-2 and IFN-γ typing was performed, using polymerase chain reaction with sequence-specific primers (PCR-SSP) assay. The frequencies of alleles, genotypes and haplotypes in AIH patients were compared to healthy controls.

RESULTS

IL-2 T allele at position +166 (rs2069763) showed significant higher frequency in AIH group (36%), compared to the controls (21%) (OR=2.06; 95% CI, 1.24-3.43, P-value<0.01). The frequency of IL-2 TT genotype at +166 position was also associated with AIH (OR=18.68, 95% CI 3.74-126.04, P-value<0.01). G/T alleles of IL-2 at -330 (rs2069762) and A/T alleles on UTR +5644 position at IFN-γ and their subsequent haplotypes, did not show significant association with AIH.

CONCLUSIONS

This study identified IL-2T allele at +166 position and TT genotype as susceptibility gene in AIH which would provide better understandings into the mechanisms of AIH and potential immune modulation therapies.

Activation of CD4 and CD8 T cell receptors and regulatory T cells in response to human proteins

This study assessed in detail the influence of four different human proteins on the activation of CD4+ and CD8+ T lymphocytes and on the formation of regulatory T cells. Human whole-blood samples were incubated with four different human proteins. The effects of these proteins on the downstream immune-system response, on the expression of extracellular activation markers on and intracellular cytokines in T lymphocytes, and on the number of regulatory T cells (T-reg cells) were investigated via flow cytometry. Incubation with β-actin or glyceraldehyde 3-phosphate dehydrogenase (GAPDH), which are cytoplasmic proteins, increased the expression of both extracellular activation markers (CD69 and HLA-DR) and intracellular cytokines but did not significantly affect the number of T-reg cells. In contrast, incubation with human albumin or insulin, which are serum proteins, reduced both extracellular activation markers and intracellular cytokine expression and subsequently increased the number of T-reg cells. These findings may help to explain the etiological basis of autoimmune diseases.

Interferon-gamma induces autophagy-associated apoptosis through induction of cPLA2-dependent mitochondrial ROS generation in colorectal cancer cells

Colorectal cancer (CRC) is the second most commonly diagnosed cancer in females and the third in males. In this work, we aim to investigate the possible anti-cancer effects of interferon-gamma (IFN-γ) in CRC cells. We observed that IFN-γ induced mitochondria-derived reactive oxygen species (ROS) production in a time-dependent manner in SW480 and HCT116 cell lines. The IFN-γ-induced mitochondrial ROS generation was dependent on the activation of cytosolic phospholipase A2 (cPLA2). In addition, a mitochondria-targeted antioxidant SS31 and/or cPLA2 inhibitor AACOCF3 abolished the IFN-γ-induced ROS production and subsequent autophagy and apoptosis. Moreover, suppression of autophagy by CQ was able to reduce IFN-γ-induced cell apoptosis. Beclin-1 gene silencing resulted in caspase-3 inactivation, decreased Bax/Bcl-2 ratio and less population of apoptotic cells. Collectively, our results suggested that IFN-γ induces autophagy-associated apoptosis in CRC cells via inducing cPLA2-dependent mitochondrial ROS production.

Type I interferon and proinflammatory cytokine levels in cerebrospinal fluid of newborns with rotavirus-associated leukoencephalopathy

OBJECTIVE

The purpose of this study was to identify whether there is an increase in type I interferon and proinflammatory cytokine levels in the cerebrospinal fluid of newborns with rotavirus-associated leukoencephalopathy.

METHODS

Levels of type I interferons (interferon-alpha and interferon-beta) and proinflammatory cytokines (interleukin-6 and interferon-gamma) were measured in the cerebrospinal fluid of 23 newborns with rotavirus-associated leukoencephalopathy (patient group) and 39 infants under 90 days-of-age (control group).

RESULTS

Cerebrospinal fluid pleocytosis was not observed in either group. Cerebrospinal fluid interleukin-6 levels were significantly higher in the patient group (7.02 ± 5.88 pg/mL) than in the control group (1.14 ± 1.90 pg/mL) (p < .0001). The mean cerebrospinal fluid interferon-gamma levels of the patient group (24.43 ± 40.16 pg/mL) were also significantly higher than those of the controls group (0.0 ± 0.0 pg/mL) (p < .0001). Cerebrospinal fluid interferon-alpha was not detected in any patient (0%) from the patient group, but was detected in four (10.3%) of the controls. Interferon-beta was detected in only two patients (8.7%) from the patient group and in one (2.6%) of the controls. Cerebrospinal fluid interleukin-6 levels correlated positively with the extent of white matter lesions on diffusion-weighted magnetic resonance imaging (r = 0.607, p = .002).

CONCLUSIONS

Significant increases in proinflammatory cytokine levels accompanied by very low detection rates of type I interferon in cerebrospinal fluid indicate that rotavirus-associated leukoencephalopathy in newborns can be correlated with central nervous system inflammatory processes without direct virus invasion into the central nervous system.

Prognostic value of interferon-gamma, interleukin-6, and tumor necrosis factor-alpha in the radiation response of patients diagnosed with locally advanced non-small-cell lung cancer and glioblastoma multiforme

Background/aim: This study aimed to investigate the effect of chemoradiotherapy (CRT) on interferon-gamma (IFN-γ), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-α), which are critical markers of the clinical radiation response of patients with locally advanced non-small-cell lung cancer (NSCLC) and glioblastoma multiforme (GBM). Materials and methods: Thirty patients who were treated with CRT and 20 healthy controls were prospectively evaluated. Circulating levels of cytokines were measured by enzyme-linked immunosorbent assay procedure. Post-CRT and pre-CRT levels were compared. Results: Post-CRT, TNF-α and IFN-γ levels were significantly lower than pre-CRT levels in the NSCLC and GBM groups, respectively. The statistical analysis did not show any significant difference between the post- and pre-CRT IL-6 levels. However, the pre-CRT IL-6 levels in the GBM group and post-CRT IL-6 levels in the NSCLC group were significantly higher than those of the control group. Conclusion: CRT affected TNF-α levels in NSCLC and IFN-γ levels in GBM, with the levels of both decreasing significantly. The IL-6 levels of the post-CRT NSCLC group were higher than those of the post-CRT GBM group. Irradiation-induced IL-6 may be responsible for tumor regrowth. Therefore, treatment with IL-6 inhibitors could be a potential therapeutic strategy for sensitizing NSCLC to irradiation in the clinic.

[Experimental study on the effect of Yiqi Wenyang Decoction on nasal mucosa infiltration of NK cells in mice with allergic rhinitis]

Objective: To observe the effect of Yiqi Wenyang Decoction on the infiltration and activation of NK cells in nasal mucosa of mouse model with allergic rhinitis (AR), and to explore the potential mechanism for effective intervention of AR with Yiqi Wenyang Decoction. Methods: Fourty-eight mice were randomly divided into blank group, model group, low, medium and high dose of Yiqi Wenyang Decoction group and Cetirizine group, with 8 rats in each group. After modeling of AR, the model group was filled with 0.9% sodium chloride solution. Yiqi Wenyang Decoction groups of each dose were given different concentrations of Yiqi Wenyang Decoction water extract, while the Cetirizine group was given aqueous solution of Cetirizine. The behavior, morphological changes of nasal mucosa and infiltration of NK cells in nasal mucosa were observed. The levels of IL-4 and INF-γ in nasal lavage fluid were measured. Besides, the drug safety was observed by acute toxicity test. Results: In the respect of behavioral scoring, middle and high dose of Yiqi Wenyang Decoction group were superior to the model group (number of sneezing: q value was 7.189, 8.748, respectively; number of scratching nose: q value was 12.074, 14.560, respectively; all P<0.05). In middle and high dose of Yiqi Wenyang Decoction group, the infiltration of NK cells and nasal lavage fluid IL-4 levels were lower than those in model group (IOD: q value was 10.073, 12.322, respectively; IOD/Area: q value was 10.954, 14.073, respectively; IL-4: q value was 4.705, 6.801, respectively; all P<0.05). There was no significant difference in nasal lavage fluid of INF-γ among each group (Fv=1.166, P>0.05). In acute toxicity test, no obvious poisoning symptoms and death occurred in mice. Conclusion: Yiqi Wenyang Decoction can control the nasal symptom, reduce the local NK cell infiltration of nasal mucosa and inhibit the expression of the 2-type cytokines released by NK cells, which may be related with the potential mechanism of effective intervention of AR with Yiqi Wenyang Decoction.

Expression levels of interferon-ɣ and type 2 deiodinase in patients diagnosed with recurrent depressive disorders

BACKGROUND

Thyroid hormones (TH) are involved in modulation of the immune system and inflammation. TH dysregulation is associated with depressive disorders. The iodothyronine deiodinases (DIOs), the key enzymes for TH synthesis, can be affected and induced by pro-inflammatory cytokines. We aimed to investigate the levels of and correlation between type 2 DIO (DIO2) and interferon-gamma (IFN-ɣ) in patients with recurrent depressive disorders (rDD).

METHODS

Data from 91 rDD patients and 105 healthy controls were analyzed. The diagnoses are based on the ICD-10 criteria (F33.0-F33.8). Expression levels of DIO2 and IFN-ɣ were estimated using the method based on the polymerase chain reaction and the enzyme-linked immunosorbent assay (ELISA).

RESULTS

The DIO2 expression on mRNA/protein levels in rDD patients (both female and males) was reduced as compared with the control subjects. No correlation between DIO2 and IFN-ɣ expression was observed.

CONCLUSION

This is the first study to reveal that one may cautiously suggest that DIO2 may be involved in the development and/or progression of rDD. The mechanisms of TH regulation on depression, however, need further investigation.

Diagnostic accuracy of interferon-gamma in pericardial effusions for tuberculous pericarditis: a meta-analysis

Background

Several studies have investigated the diagnostic accuracy of tests of pericardial effusion interferon-gamma for tuberculous pericarditis in patients with pericardial effusion, but the results have varied. The aim of this study was to investigate the diagnostic accuracy of interferon-gamma for tuberculous pericarditis using meta-analysis.

Methods

The PubMed and EMBASE databases were searched to identify studies investigating the diagnostic accuracy of tests for interferon-gamma in pericardial effusion for tuberculous pericarditis. The quality of eligible studies was assessed by the revised Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2), and the sensitivities and specificities of interferon-gamma across eligible studies were pooled by a bivariate model.

Results

A total of four studies encompassing 488 subjects were included. The pooled sensitivity, specificity, positive and negative likelihood ratios (NLRs) were 0.97 [95% confidence interval (CI): 0.87-0.99], 0.99 (95% CI: 0.74-1.00), 187 (95% CI: 3-12,542) and 0.03 (95% CI: 0.01-0.14), respectively.

Conclusion

Testing for interferon-gamma in cases of pericardial effusion is adequate for identifying or ruling out tuberculous pericarditis.

Interleukin-2 and Interferon-Gamma Single Nucleotide Polymorphisms in Iranian Patients with Chronic Heart Failure

BACKGROUND

Inflammatory cytokines have been known to be associated with Chronic Heart Failure (CHF). Given the importance of cytokines in the context of the failing heart, the prevalence of Interleukin-2 (IL-2) and Interferon-gamma (IFN-γ) polymorphisms was studied in patients with CHF due to ischemic heart disease in a case-control study.

METHODS

Fifty-six Iranian patients with CHF were enrolled in this study as the case group and compared with 139 healthy subjects, using polymerase chain reaction with sequence-specific primers method, so as to determine the frequency of alleles, genotypes and haplotypes of IFN-γ (+874 A/T) and IL-2 (-330 G/T, +166 G/T) SNPs.

RESULTS

The GG genotype at IL-2 -330 in patients with CHF was significantly over-represented in comparison with the control group (p=0.013). Such a positive genotypic association was also observed for IL-2 +166/TT (p=0.022). Meanwhile, the GT genotype frequency at IL-2 -330/GT in the patient group was significantly lower than the one in healthy controls (p=0.049). No significant association was detected between the IFN-γ gene polymorphisms and individuals' susceptibility to CHF.

CONCLUSION

Certain genotypes in IL-2 gene were overrepresented in patients with CHF, which could render individuals more vulnerable to this disease.

The neonatal anti-viral response fails to control measles virus spread in neurons despite interferon-gamma expression and a Th1-like cytokine profile

Neonates are highly susceptible to viral infections in the periphery, potentially due to deviant cytokine responses. Here, we investigated the role of interferon-gamma (IFNγ), a key anti-viral in the neonatal brain. We found that (i) IFNγ, which is critical for viral control and survival in adults, delays mortality in neonates, (ii) IFNγ limits infiltration of macrophages, neutrophils, and T cells in the neonatal brain, (iii) neonates and adults differentially express pathogen recognition receptors and Type I interferons in response to the infection, (iv) both neonates and adults express IFNγ and other Th1-related factors, but expression of many cytokines/chemokines and IFNγ-responsive genes is age-dependent, and (v) administration of IFNγ extends survival and reduces CD4 T cell infiltration in the neonatal brain. Our findings suggest age-dependent expression of cytokine/chemokine profiles in the brain and distinct dynamic interplays between lymphocyte populations and cytokines/chemokines in MV-infected neonates.

•

The role of the anti-viral cytokine interferon-gamma (IFNγ) is investigated during a neonatal viral infection in CNS neurons.

•

IFNγ did not prevent mortality in neonates, but it slowed disease progression.

•

IFNγ reduced infiltration of neutrophils, macrophages, and T cells in the neonatal CNS.

•

Both adult and neonatal mice expressed Th1-like cytokines, including IFNγ and some IFNγ-stimulated genes, during infection.

•

Despite a Th1-like cytokine profile in the neonatal CNS, the cytokine milieu is ineffective at controlling viral spread.

Assessment of NK Cell Metabolism

There has been increasing recognition of the importance of metabolism on immune cell differentiation, homeostasis, and function. Recently, our lab and others have begun to investigate the metabolic requirements for NK cell differentiation and activation. Here, we describe approaches for the in vitro assessment of NK cell metabolism. We present methods for using inhibitors to alter cellular metabolism, measurement of intracellular ATP in NK cells, assessment of real-time glycolysis and oxidative phosphorylation by an extracellular flux assay from Seahorse Biosciences, and some basic protocols for stimulation of NK cells via cytokines and receptors.