Role Of Interferon Research Articles

The role of interferons in preschool wheeze

Recurrent wheeze is a common condition in early childhood years and has a significant effect on children, caregivers, and health-care services. Although most preschool children with recurrent wheeze have no further sequelae, nearly one-third will require regular asthma medications and clinical reviews thereafter. Preschool children with recurrent wheeze and multiple allergies, not just allergic sensitisation, are at higher risk of symptom persistence. Most allergen-sensitised children do not have multiple allergies.

Immune Response to COVID-19: Can We Benefit from the SARS-CoV and MERS-CoV Pandemic Experience?

The global range and high fatality rate of the newest human coronavirus (HCoV) pandemic has made SARS-CoV-2 the focus of the scientific world. Next-generation sequencing of the viral genome and a phylogenetic analysis have shown the high homology of SARS-CoV-2 to other HCoVs that have led to local epidemics in the past. The experience acquired in SARS and MERS epidemics may prove useful in understanding the SARS-CoV-2 pathomechanism and lead to effective treatment and potential vaccine development. This study summarizes the immune response to SARS-CoV, MERS-CoV, and SARS-CoV-2 and focuses on T cell response, humoral immunity, and complement system activation in different stages of HCoVs infections. The study also presents the quantity and frequency of T cell responses, particularly CD4+ and CD8+; the profile of cytokine production and secretion; and its relation to T cell type, disease severity, and utility in prognostics of the course of SARS, MERS, and COVID-19 outbreaks. The role of interferons in the therapy of these infections is also discussed. Moreover, the kinetics of specific antibody production, the correlation between humoral and cellular immune response and the immunogenicity of the structural HCoVs proteins and their utility in the development of a vaccine against SARS, MERS, and COVID-19 has been updated.

Multiple sclerosis, human herpesvirus 4 and thyroid collision tumor: A case report.

The role of interferon β-1b (IFNβ-1b), used for multiple sclerosis (MS) therapy, in cancer occurrence is uncertain. There is evidence supporting the role of human herpesvirus 4 [Epstein-Barr virus (EBV)] in thyroid cancer and MS. Simultaneous occurrence of papillary and medullary carcinomas is rare, and its association with MS in a young woman raises questions. A 46-year-old female patient was diagnosed with relapsing-remitting multiple sclerosis in 2008. In 2018, cervical MRI detected a thyroid nodule with right cervical adenopathy. Her thyroid function was normal, but increased calcitonin levels were found (70.53 pg/ml; normal value: <9.82 pg/ml). EBV serology tested positive. Paraclinical studies ruled out multiple endocrine neoplasia syndrome. Whole thyroid resection with whole cervical lymph node dissection was performed. To our knowledge, this is the first case that describes an association between MS and thyroid collision tumors. Histological examination ascertained both papillary and medullary thyroid cancer. After surgery, the calcitonin level normalized, and the patient received a therapeutic dose of iodine-131. IFNβ-1b therapy was discontinued. The coexistence of thyroid cancers in MS patients could be explained by immune-mediated inflammation. Although EBV is not the only agent responsible for the development of MS or thyroid cancers, it could be considered a contributory factor in our case. Further research on EBV involvement in the occurrence of simultaneous immune pathologies in various organs is needed to confirm these data.

The impact of regional astrocyte interferon-\u03b3 signaling during chronic autoimmunity: a novel role for the immunoproteasome

BackgroundIn early autoimmune neuroinflammation, interferon (IFN)γ and its upregulation of the immunoproteasome (iP) is pathologic. However, during chronic multiple sclerosis (MS), IFNγ has protective properties. Although dysregulation of the iP has been implicated in neurodegeneration, its function remains to be fully elucidated. Here, we demonstrate that IFNγ signaling in regional astrocytes induces the iP and promotes protection of the CNS during chronic autoimmunity.MethodsIn a multiple sclerosis (MS) brain, we evaluated mRNA expression and labeled postmortem MS brainstem and spinal cord for iP subunits and indicators of oxidative stress. Primary regional human astrocytes were analyzed for iP regulation and function by quantitative reverse transcription-polymerase chain reaction (qRT-PCR), Western blot, OxyBlot, and reactive oxygen species and caspase activity detection assays. Following immunization with myelin oligodendrocyte glycoprotein (MOG)35-55, the role of IFNγ signaling and the iP during chronic experimental autoimmune encephalomyelitis (EAE) were assessed using pharmacologic inhibition of the iP and genetic interruption of IFNγ signaling specifically in astrocytes. Central nervous system (CNS) tissues were analyzed by immunohistochemistry (IHC) and immunofluorescence, and cell-specific colocalization was quantified.ResultsIn MS tissue, iP expression was enhanced in the spinal cord compared to brainstem lesions, which correlated with a decrease in oxidative stress. In vitro, IFNγ stimulation enhanced iP expression, reduced reactive oxygen species burden, and decreased oxidatively damaged and poly-ubiquitinated protein accumulation preferentially in human spinal cord astrocytes, which was abrogated with the use of the iP inhibitor, ONX 0914. During the chronic phase of an MS animal model, EAE, ONX 0914 treatment exacerbated the disease and led to increased oxidative stress and poly-ubiquitinated protein buildup. Finally, mice with astrocyte-specific loss of the IFNγ receptor exhibited worsened chronic EAE associated with reduced iP expression, enhanced lesion size and oxidative stress, and poly-ubiquitinated protein accumulation in astrocytes.ConclusionsTaken together, our data reveal a protective role for IFNγ in chronic neuroinflammation and identify a novel function of the iP in astrocytes during CNS autoimmunity.

Interferon Therapy in Myelofibrosis: Systematic Review and Meta-analysis

BackgroundMyelofibrosis (MF) is a Philadelphia chromosome–negative myeloproliferative neoplasm characterized by progressive bone marrow failure, increased risk of progression to acute myeloid leukemia, and constitutional symptoms. For over 3 decades, various formulations of interferon (IFN) have been used for the treatment of MF, with variable results, and the role of IFN in the treatment of MF is evolving. Patients and MethodsFor this systematic review and meta-analysis, Medline and Embase via Ovid, Scopus, Cochrane Central Register of Controlled Trials (CENTRAL), and Web of Science were searched from inception through March 2019 for studies of pegylated IFN (peg-IFN) and non–peg-IFN in MF patients. The primary outcome of overall response rate was defined as a composite of complete response, partial response, complete hematologic response, and partial hematologic response. Random-effects models were used to pool overall response rate, and metaregression analyses were performed to compare peg-IFN and non-–peg-IFN formulations. ResultsAmong the 10 studies with 141 MF patients included, the overall response rate was 49.9% (95% confidence interval [CI], 30.4-69.3), and there was no statistically significant difference (P = .99) between peg-IFN (50.0%; 95% CI, 26.2-73.9; I2 = 76.9%) and non–peg-IFN (49.6%; 95% CI, 20.5-79.0; I2 = 56.7%). Treatment discontinuation resulting from adverse events was common with non–peg-IFN at 35.8% (95% CI, 3.5-68.1) per year, and less in the one study on peg-IFN (0.5% per year). ConclusionIFN can lead to hematologic improvements in a subset of MF patients, but study quality is limited and heterogenous. Biomarkers predicting response to IFN and formulations with improved tolerability are needed.

Interferon in the CNS

While the role of interferon during systemic disease is well known and its immune modulating functions and its role in antiviral activity were extensively studied, the role of IFN-I in the brain is less clear. Here we summarize the most important literature on IFN in homeostasis of the CNS and induction of an IFN response during viral infection in the brain. Furthermore, we present work on the roles of IFN in the developing brain as well as during inflammation in the brain. Lastly, we aim to enlighten the functions of IFN on the blood-brain barrier as well as circulation and in cognitive and psychological functions and degeneration. In short, CNS astrocytes produce IFN-β, which is of high relevance for homeostasis in the brain. IFN-β regulates phagocytic removal of myelin debris by microglia. IFN-I limits the permeability of the blood-brain barrier. Disruption of the blood-brain barrier facilitates entrance of peripheral lymphocytes and inflammation. Viral infections during vulnerable phases of embryonic development cause severe fetal pathology and debilitating impairments to human infants. The roles of IFN in these scenarios are diverse and include deficits due to overproduction of IFN during the developmental stage of the brain as seems to be the case in pseudo-TORCH2.

The Role of Interferon, Inflammation and Infection in Aplastic Anemia

Bone marrow failure (BMF) syndromes are a group of acquired and inherited diseases characterized by failed production of blood and immune cells, and profound bone marrow aplasia. Acquired BMF, including severe aplastic anemia (SAA), has been linked to radiation, chemical exposure, and infection, and the precise mechanisms of disease likely differ on a case-by-case basis. Inflammation and immune-mediated destruction of the marrow is a key driver of SAA, thus disease management centers on immunosuppressive therapy (IST) and, especially in young patients, bone marrow transplantation (BMT). However, not all patients are good transplant candidates and IST responsiveness varies, therefore, more specific treatments are necessary. HSC loss is a key feature of SAA, though it has been unclear if inflammation depletes HSCs directly or does so through the microenvironment. Interferons (IFNs) are proteins produced in response to microbial infections that play key roles in limiting pathogen spread and eradicating infections. While transient inflammatory responses and IFN production are often necessary for appropriate host defense, elevated levels of IFN-gamma (IFNγ) have long been associated with BMF syndromes, and type I IFNs (alpha and beta) are well documented to cause bone marrow aplasia during viral infection 1. In models of infection and inflammation IFNs can activate HSCs to proliferate and differentiate, but can also impair proliferation, and in both cases result in restricting HSC self-renewal 2-5. The precise mechanisms whereby IFNs mediate SAA and whether IFNs act directly on HSCs have remained elusive. In a mouse model of SAA driven by T cell-derived IFNγ we found that IFNγ-dependent HSC loss was associated with reduced marrow stromal cells, but a marked preservation of bone marrow-resident macrophages (MΦs) 6. Our data were consistent with findings from SAA patient marrow that also demonstrates MΦ persistence, despite significant reductions in nearly all other stromal and hematopoietic cell types 7. Moreover, we found that IFNγ was necessary for the maintained pool of MΦs. Depleting MΦs using Clodronate-loaded liposomes, or abrogating IFNγ signaling specifically in MΦs was shown to rescue HSCs and reduce SAA-associated mortality. Targeting MΦs during SAA improved thrombocytopenia, increased BM megakaryocytes, preserved platelet-primed HSCs, and increased the platelet-repopulating capacity of transplanted HSCs 6. During SAA IFNγ and MΦs were required for elevated levels of particular chemokines in the bone marrow, including CCL3, CCL4, and CCL5, which were further identified as downstream targets for mitigating SAA pathogenesis. The identification of MΦ function as a key determinant of IFNγ-dependent HSC loss in SAA furthers our understanding of disease pathogenesis and illustrates an important role for the microenvironment in SAA. These studies may reveal potential therapeutic strategies to complement current treatments for SAA that avoid generalized immunosuppression and potentially improve long-term outcomes. Smith JN, Kanwar VS, MacNamara KC. Hematopoietic Stem Cell Regulation by Type I and II Interferons in the Pathogenesis of Acquired Aplastic Anemia. Frontiers in immunology. 2016;7:330. Baldridge MT, King KY, Boles NC, Weksberg DC, Goodell MA. Quiescent haematopoietic stem cells are activated by IFN-gamma in response to chronic infection. Nature. 2010;465(7299):793-797. de Bruin AM, Demirel O, Hooibrink B, Brandts CH, Nolte MA. Interferon-gamma impairs proliferation of hematopoietic stem cells in mice. Blood. 2013;121(18):3578-3585. MacNamara KC, Jones M, Martin O, Winslow GM. Transient activation of hematopoietic stem and progenitor cells by IFNgamma during acute bacterial infection. PLoS One. 2011;6(12):e28669. Matatall KA, Jeong M, Chen S, et al. Chronic Infection Depletes Hematopoietic Stem Cells through Stress-Induced Terminal Differentiation. Cell reports. 2016;17(10):2584-2595. McCabe A, Smith JNP, Costello A, Maloney J, Katikaneni D, MacNamara KC. Hematopoietic stem cell loss and hematopoietic failure in severe aplastic anemia is driven by macrophages and aberrant podoplanin expression. Haematologica. 2018;103(9):1451-1461. Park M, Park CJ, Jang S, et al. Reduced expression of osteonectin and increased natural killer cells may contribute to the pathophysiology of aplastic anemia. Appl Immunohistochem Mol Morphol. 2015;23(2):139-145. Disclosures No relevant conflicts of interest to declare.

The interferon stimulated gene viperin, restricts Shigella. flexneri in vitro

The role of interferon and interferon stimulated genes (ISG) in limiting bacterial infection is controversial, and the role of individual ISGs in the control of the bacterial life-cycle is limited. Viperin, is a broad acting anti-viral ISGs, which restricts multiple viral pathogens with diverse mechanisms. Viperin is upregulated early in some bacterial infections, and using the intracellular bacterial pathogen, S. flexneri, we have shown for the first time that viperin inhibits the intracellular bacterial life cycle. S. flexneri replication in cultured cells induced a predominantly type I interferon response, with an early increase in viperin expression. Ectopic expression of viperin limited S. flexneri cellular numbers by as much as 80% at 5hrs post invasion, with similar results also obtained for the intracellular pathogen, Listeria monocytogenes. Analysis of viperins functional domains required for anti-bacterial activity revealed the importance of both viperin’s N-terminal, and its radical SAM enzymatic function. Live imaging of S. flexneri revealed impeded entry into viperin expressing cells, which corresponded to a loss of cellular cholesterol. This data further defines viperin’s multi-functional role, to include the ability to limit intracellular bacteria; and highlights the role of ISGs and the type I IFN response in the control of bacterial pathogens.

Viral Innate Immune Evasion and the Pathogenesis of Emerging RNA Virus Infections.

Positive-sense single-stranded RNA (+ssRNA) viruses comprise many (re-)emerging human pathogens that pose a public health problem. Our innate immune system and, in particular, the interferon response form the important first line of defence against these viruses. Given their genetic flexibility, these viruses have therefore developed multiple strategies to evade the innate immune response in order to optimize their replication capacity. Already many molecular mechanisms of innate immune evasion by +ssRNA viruses have been identified. However, research addressing the effect of host innate immune evasion on the pathology caused by viral infections is less prevalent in the literature, though very relevant and interesting. Since interferons have been implicated in inflammatory diseases and immunopathology in addition to their protective role in infection, antagonizing the immune response may have an ambiguous effect on the clinical outcome of the viral disease. Therefore, this review discusses what is currently known about the role of interferons and host immune evasion in the pathogenesis of emerging coronaviruses, alphaviruses and flaviviruses.

Role of Interferon (IFN)α in "Cocktails" for the Generation of (Leukemia-derived) Dendritic Cells (DCleu) From Blasts in Blood From Patients (pts) With Acute Myeloid Leukemia (AML) and the Induction of Antileukemic Reactions.

Strategies to stabilize remissions by specific elimination of residual acute myeloid leukemia (AML) blasts are needed. Leukemia-derived dendritic cell (DCleu/DC) generated from myeloid blasts improve antileukemic T-cell reactivity and install T-cell memory. Interferon (IFN)α-DC methods produce DCleu from chronic myeloid leukemia-patients (pts') blood. Various INFα-containing versus other DC methods were studied to produce DCleu (evaluated by flowcytometry) from AML-pts' blast-containing mononuclear (MNC) or whole blood (WB). After DCleu/DC stimulation in mixed lymphocyte cultures, T cells' potential to gain antileukemic cytotoxicity was studied and correlated with different DC methods and DCleu/DC counts. (1) Generation of DCleu/DC: (a) "IFN-GIT" [containing granulocyte macrophage-colony stimulating factor (GM-CSF)+IFNα+ tumor necrosis factor (TNF)-α] produced DC successfully (≥10% DC, ≥5% DCleu/cells) from AML-MNC (WB) in 54 (56%), "MCM-Mimic" in 76 (75%), "Picibanil" in 83 (64%), and "Calcium-ionophore" in 42 (67%) of cases. Proportions of DC subtypes in MNC (WB) were comparable with all DC methods, (b) IFNα combinations containing only GM-CSF+IFNα or only IFNα showed low efficiency to produce DCleu/DC from MNC (WB) compared with "IFN-GIT." (2) Antileukemic functionality: DCleu/DC-stimulated T cells showed improved leukemia cytotoxicity compared with blast cells or unstimulated T cells. The highest blast proliferation (=insufficient T cells) was seen with "IFN-GIT" DC-stimulated T cells. Probability to respond to immunotherapy or to obtain blast lysis of DC-stimulated T cells correlated with high proportions of DCleu/DC after DC culture, independent of DC-generating methods. (3) Cytokine release profiles: levels of interleukin-6, IFN-γ, and interleukin-2 were significantly lower in DC culture supernatants (from MNC/WB) with "IFN-GIT" compared with "MCM," "Pici," and "Ca" DC supernatants. Our data show that (1) WB culture simulates AML-pts' in vivo situation, (2) DC generation is possible from AML-MNC (WB) with IFNα-containing and other DC methods, (3) successful IFNα-DC generation needs GM-CSF+IFNα+TNF-α (IFN-GIT); however, "IFN-GIT" produces less DCleu/DC compared with other (non-IFNα) DC methods, (4) T cells stimulated with "IFN-GIT"-produced DCleu/DC yielded comparable antileukemic cytotoxicity; however, in cases without achieved blast lysis, an increased blast proliferation was observed.

Gene expression analysis delineates the potential roles of multiple interferons in systemic lupus erythematosus

A role for interferon (IFN) in systemic lupus erythematosus (SLE) pathogenesis is inferred from the prominent IFN gene signature (IGS), but the major IFN species and its relationship to disease activity are unknown. A bioinformatic approach employing individual IFN species gene signatures to interrogate SLE microarray datasets demonstrates a putative role for numerous IFN species, with prominent expression of IFNB1 and IFNW signatures. In contrast with other SLE-affected organs, the IGS is less prominent in lupus nephritis. SLE patients with active and inactive disease have readily detectable IGS and the IGS changes synchronously with a monocyte signature but not disease activity, and is significantly related to monocyte transcripts. Monocyte over-expression of three times as many IGS transcripts as T and B cells and IGS retention in monocytes, but not T and B cells from inactive SLE patients contribute to the lack of correlation between the IGS and SLE disease activity.

Toll-like receptor 9–dependent interferon production prevents group 2 innate lymphoid cell–driven airway hyperreactivity

Group 2 innate lymphoid cells (ILC2s) are important mediators of allergic asthma. Bacterial components, such as unmethylated CpG DNA, a Toll-like receptor (TLR) 9 agonist, are known to possess beneficial immunomodulatory effects in patients with T cell-mediated chronic asthma. However, their roles in regulating ILC2s remain unclear. We sought to determine the role of TLR9 activation in regulating ILC2 function and to evaluate the therapeutic utility of an immunomodulatory microparticle containing natural TLR9 ligand (MIS416). We evaluated the immunomodulatory effects of CpG Ain IL-33-induced airway hyperreactivity (AHR) and airway inflammation. The roles of interferons were examined invivo and invitro by using signal transducer and activator of transcription 1 (Stat1)-/- mice and neutralizing antibodies against IFN-γ and IFN-α/β receptor subunit 1, and their cellular sources were identified. The therapeutic utility of MIS416 was investigated in the Alternaria alternata model of allergic asthma and in humanized NSG mice. We show that TLR9 activation by CpG Asuppresses IL-33-mediated AHR and airway inflammation through inhibition of ILC2s. Activation of TLR9 leads to production of IFN-α, which drives IFN-γ production by natural killer cells. Importantly, IFN-γ is essential for TLR9-driven suppression, and IFN-α cannot compensate for impaired IFN-γ signaling. We further show that IFN-γ directly inhibits ILC2 function through a STAT1-dependent mechanism. Finally, we demonstrate the therapeutic potential of MIS416 in A alternata-induced airway inflammation and validated these findings in human subjects. TLR9 activation alleviates ILC2-driven AHR and airway inflammation through direct suppression of cell function. Microparticle-based delivery of TLR9 ligands might serve as a therapeutic strategy for asthma treatment.

Interferons: pathogenetic rationale for the treatment of external genital endometriosis and clinical efficacy

Hypothesis/aims of study. Endometriosis is the main cause of infertility and social maladjustment in women, caused by the presence of inflammatory endometriotic implants outside the uterus. A number of chemokines, including interferons, compromise the immune response on the development of endometriosis raising the interest to the investigation of interferons in this context. Based on this, the purpose of this review was to study the role of interferons in the pathogenesis of external genital endometriosis and to assess the possibility of their application within comprehensive pathogenesis-based therapy.&#x0D; Study design, materials and methods: literature data of national and international investigations for the period from 1996 to 2018; systematic analysis and evaluation of the literary data.&#x0D; Conclusion. Type I interferons seem to be promising agents for understanding of the pathogenesis of endometriosis, and can be considered as targeted therapy for this disease. The mechanisms of their functions require a further study. Type II interferons may be used in the future as diagnostic markers for the assessment of the disease severity.

Natural killer cells induce neutrophil extracellular trap formation in venous thrombosis

Essentials Neutrophil extracellular traps (NETs) are generated during deep vein thrombosis (DVT). The role of interferon γ (IFNγ) and natural killer (NK) cells in NET formation was studied. IFNγ promote venous thrombosis through NET formation. NK cell depletion reduces DVT. SUMMARY: Background Neutrophils contribute to venous thrombosis through the release of neutrophil extracellular traps (NETs), but the mechanism triggering their formation remains unclear. Invitro data show that interferon (IFN)-γ induces the formation of NETs. Objectives To determine whether IFN-γ and the transcription factor T-box expressed on T cells (Tbet) promote venous thrombosis through neutrophil activation. Methods Venous thrombosis was induced by flow restriction in the inferior vena cava in IFN-γ-/- , Tbet-/- or wild-type (WT) mice. After 48h, thrombus size was measured by the use of high-frequency ultrasound. NET formation was determined by immunofluorescence. Results and Conclusions Thrombus formation was reduced in Tbet-/- and IFN-γ-/- mice, suggesting that Tbet/IFN-γ-expressing cells are required for venous thrombosis. The number of NETs formed during thrombosis was significantly lower in Tbet-/- and IFN-γ-/- mice. NET formation was also decreased in WT mice treated with an IFN-γ-blocking antibody. Injection of recombinant IFN-γ into IFN-γ-/- mice rescued the phenotype. Natural killer (NK) cells were specifically depleted prior to venous thrombosis induction. NK cell depletion results in decreased NET formation and smaller thrombi, suggesting that NK cells are required for thrombus development. In depleted mice, adoptive transfer of WT NK cells induced a similar thrombosis burden as in WT mice. In contrast, adoptive transfer of IFN-γ -/- NK cells resulted in thrombi similar in size to those in depleted mice. Invitro, we showed that WT neutrophils released fewer NETs when they were cocultured with IFN-γ-/- NK cells. This study demonstrates that NK cell-dependent IFN-γ production is crucial for thrombus development by promoting the formation of NETs by neutrophils.

Interferon-alpha 2 but not Interferon-gamma serum levels are associated with intramuscular fat in obese patients with nonalcoholic fatty liver disease

BackgroundIntramuscular triglycerides (IMTGs) represent an important energy supply and a dynamic fat-storage depot that can expand during periods of elevated lipid availability and a fatty acid source. Ultrasonography (US) of human skeletal muscles is a practical and reproducible method to assess both IMTG presence and entity. Although a crosstalk between cytokines in skeletal muscle and adipose tissue has been suggested in obesity, condition leading to hepatic steatosis (HS) or better defined as nonalcoholic fatty liver disease and cancer, there are still questions to be answered about the role of interferons (IFNs), alpha as well as gamma, and IMTG in obesity. We aimed at discovering any correlation between IFNs and IMTG.MethodsWe analysed anthropometric data, metabolic parameters and imaging features of a population of 80 obese subjects with low-prevalence of co-morbidities but HS in relation to IFNs serum levels. A population of 38 healthy subjects (21 males) served as controls. The levels of serum IFNs were detected by a magnetic bead-based multiplex immunoassays.ResultsSerum concentrations of IFN-alpha 2 were increased, while serum levels of IFN-gamma were decreased confronted with those of controls; the severity of IMTG, revealed at US as Heckmatt scores, was inversely predicted by IFN-alpha 2 serum concentrations; IMTG scores were not predicted by serum levels of IFN-gamma; IMTG scores were predicted by HS severity, ascertained at US; HS severity was predicted by visceral adipose tissue, assessed by US, but the latter was not instrumental to IMTG.Discussion and conclusionThis study has added some pieces of observation about the cytokine network regulating the interplay between IMTG and obesity in obese patients with HS.

Single Center Retrospective Study of Essential Thrombocythaemia Diagnosed Patients Treated with Interferon - Benefit and Tolerability

Introduction: Therapeutic approaches for patients (pts) with essential thrombocythaemia (ET) are heterogeneous and the optimal treatment strategy to achieve reduction in risks of thrombosis, hemorrhage and transformation to myelofibrosis or leukemia in the long term remains unclear. Standard first-line therapy choice for ET, supported by data from randomized trials, remains low-dose aspirin with hydroxycarbamide (HC), but the role of interferon (IFN) is increasingly highlighted. Recently conducted randomised studies provide short term information but at present we rely upon long term well annotated patient cohorts to guide appropriate therapy.Objective: Descriptive, single-center, retrospective study of ET pts on IFN treatment to evaluate benefit and tolerability.Methods: Medical record data were collected from 2004 until June 2018. Inclusion criteria: diagnosis of ET (WHO criteria) on treatment with IFN (IFN alpha-2a/b and PEG-IFN alpha-2a/b) with IFN follow-up time of at least 6 months.Results: 53 pts (36 female, median age 44 yrs, range 25-71 yrs), with a median age at diagnosis 37 yrs, range 14-63 yrs, were treated with IFN alpha-2a/b (11 pts) or PEG-IFN 2a/b (42pts). The median duration of IFN therapy was 4.2 yrs and median follow-up 9.0 yrs (range 1.4-27.3 yrs).Intermediate and high-risk ET, according to IPSET score, was identified in 27 pts (~50%), indications for treatment initiation in the low risk population (26 pts) included extreme thrombocytosis (17 pts), a thromboembolic event (TE) (1 pt), age over 60 yrs (1 pt), pregnancy (2 pts), high symptom burden (4 pts) and surgery (1 pt).Concerning driver mutation status, 22 (41.5%) pts had the JAK2 V617F mutation; 22 (41.5%) had CALR type 1/2 mutations, 8 (15%) were Triple negative and molecular information was lacking for 1 pt.Regarding treatment, the median time from diagnosis to first line of treatment was 0.6 yrs and IFN was initiated as first line therapy in 25 pts (~50%). The median number of lines of therapy prior to IFN was 2. The median time to obtain a haematological response (HR) on IFN (plts <400x 109/L) was ~10 months (range 0-45 months). At last follow-up, 40/53 pts were in HR and 13/53 pts in partial response (PR; arbitrarily defined as plts <700 X 109/L). 7 of the latter group remained on IFN treatment with a median plt count of 488 X 109/L (range 424-660 X 109/L) Overall 52.5% of the patients in HR were JAK2 V617F mutated and 71% of the patients who did not achieve HR were CALR positive.A total of 19 TE were reported in 15/53 pts (28%), 4 pts had 2 TE; abdominal thrombosis (2/19), cerebral thrombosis, including CVA, TIA and CVT (8/19), myocardial infarct (2/19), and other (retinal vein 2/19; upper and lower limbs 3/19 and digital ischemia (2/19). Of the cohort with TE, 47% were JAK2 V617F mutated, 20 % were CALR mutated and 33% were Triple Negative. Concerning IPSET score, 80 % were Intermediate (40%) and high-risk (40%) ET. Prior to or at diagnosis, 10 TE occurred and only 4 were diagnosed in patients on cytoreductive therapy. Of these 2/4 affected pts already on treatment had another thromboembolic risk factor: 1 pt with antiphospholipid syndrome had 2 episodes of digital ischemia; 1 pt had a second upper limb thrombosis (first at diagnosis in different localization) after a laparoscopic cholecystectomy, 2/4 did not achieve PR, 1 pt with poor compliance to IFN treatment had a lower limb thrombophlebitis and 1 pt had a TIA on HC; neither of these latter patients achieved a PR. None of the pts had a hemorrhagic complication on IFN.During a medium follow up period of 9 yrs, only 6 pts had to discontinue IFN therapy due to persistent, ≥ grade 3 toxicity: fatigue, depression or thyroiditis. No patient had disease progression.Discussion: In this young cohort of ET pts treatment with IFN was well tolerated with high rates of response and only 6/53 (11%) pts discontinuing. TE on IFN treatment were rare and all reported cases were in pts with an additional risk factor or in those who had not achieved a PR; this highlights important practice points for enhanced vigilance and consideration to therapy escalation or switch. Our data corroborates the previously reported efficacy of IFN in the treatment of ET, with an ability to control plts count and prevent thromboembolic and haemorrhagic events. Due to its efficacy and absence of leukaemogenic effect it should be considered as an option for first line treatment of young ET pts requiring cytoreductive therapy. DisclosuresMcLornan:Novartis: Speakers Bureau; Jazz Pharmaceutical: Speakers Bureau. Radia:Novartis: Speakers Bureau; Blueprint: Consultancy. Harrison:Gilead: Honoraria, Speakers Bureau; Roche: Consultancy, Honoraria; Novartis: Consultancy, Honoraria, Research Funding, Speakers Bureau; Celgene: Consultancy, Honoraria, Speakers Bureau; CTI BioPharma: Consultancy, Honoraria.

Expanding the spectrum of APOL1-related renal disease: de novo collapsing glomerulopathy following kidney transplant

Santoriello etal. report a series of 38 cases of de novo collapsing glomerulopathy following kidney transplant. Associations included acute rejection, viral infection, and APOL1 high-risk genotype (the latter in 9 cases). Risk factors for collapsing glomerulopathy included acute rejection, viral infection, acute vaso-occlusive disease, and an African American donor. The data are suggestive of, but do not directly establish, a role for interferon in these associations.

Species-specific inhibition of capripoxvirus replication by host antiviral protein kinase R.

The role of interferon (IFN)‐induced protein kinase R (PKR) in capripoxvirus (CaPV)‐infected cells remains unknown. In this study, we show that CaPV infection triggered PKR and eukaryotic translation initiation factor 2 alpha (eIF2α) protein phosphorylation in a dose‐dependent manner, and that this leads to decreased CaPV replication. Overexpression of PKR compromised viral gene expression and inhibited sheeppox virus (SPPV) replication. Downregulation of PKR with siRNAs significantly decreased eIF2α phosphorylation and reduced the mRNA level of IFN‐β, which increased virus replication. In luciferase assays, species‐different CaPVs K3L proteins inhibited sheep PKR (sPKR): goatpox virus K3L strongly inhibited sPKR and goat PKR (gPKR), but SPPV K3L only partially inhibited gPKR. These results are the first to show that SPPV infection induces phosphorylation of eIF2α through PKR activation, which then results in restriction of CaPV replication. Furthermore, our data show that CaPV K3L inhibits PKR in a species‐specific manner. The results presented are consistent with the hypothesis that different levels of PKR inhibition by K3L orthologs from various viruses could potentially contribute to the host range function of K3L.

Interferon γ suppresses dentin sialophosphoprotein in oral squamous cell carcinoma cells resulting in antitumor effects, via modulation of the endoplasmic reticulum response.

The expression of proinflammatory cytokines in various malignant neoplasms is widely considered to represent the host immune response to tumor development. The role of interferon (IFN)γ in head and neck squamous cell carcinoma, and its association with endoplasmic reticulum (ER) stress pathways, remains a subject of ongoing investigation. Dentin sialophosphoprotein (DSPP), which is a member of the small integrin-binding N-linked glycoproteins family, has been implicated in malignant transformation and invasion of oral squamous cell carcinoma (OSCC). Recent studies have established matrix metalloproteinase (MMP)20 as the cognate MMP partner of DSPP. The present study examined the effects of IFNγ treatment on DSPP and MMP20 expression, ER stress, the unfolded protein response (UPR), and calcium (Ca) homeostasis regulatory mechanisms in OSCC cells. The OSC2 OSCC cell line was treated with IFNγ at specific time-points. At each time-point, the mRNA expression levels of DSPP and MMP20, and those of ER-stress-, UPR- and Ca homeostasis-associated proteins [78-kDa glucose-regulated protein (GRP78), sarco/endoplasmic reticulum Ca2+-ATPase (SERCA2b), inositol 1,4,5-trisphosphate receptor (IP3r), protein kinase R-like ER kinase (PERK) and inositol-requiring enzyme 1 (IRE1)], were assessed by reverse transcription-quantitative polymerase chain reaction. The protein expression levels of B-cell lymphoma 2 (Bcl-2), Bcl-2-associated X protein (Bax), proliferating cell nuclear antigen (PCNA) and cytochrome c were analyzed by western blotting. Cell viability, apoptosis and migration were evaluated by MTT, Annexin V-fluorescein isothiocyanate flow cytometry and wound-healing assays, respectively. IFNγ treatment significantly downregulated the mRNA expression levels of the major ER stress regulator GRP78 and, to a lesser extent, the UPR-associated molecule IRE1; however, IFNγ had no significant effect on PERK. With regards to ER Ca homeostasis molecules, treatment with IFNγ downregulated the mRNA expression levels of SERCA2b and upregulated those of IP3r. Furthermore, DSPP and MMP20 mRNA expression levels were significantly reduced following IFNγ treatment. Notably, treatment with IFNγ hampered OSC2 migration, reduced cell viability and PCNA protein expression, enhanced apoptosis, downregulated Bcl-2, and upregulated Bax and cytochrome c. Overall, IFNγ inhibited OSCC cell viability and migration, and increased apoptosis, possibly by regulating ER stress and UPR mechanisms. In addition, IFNγ-induced DSPP and MMP20 downregulation may correspond with alteration in ER Ca homeostasis.

Murine host response to Neisseria gonorrhoeae upper genital tract infection reveals a common transcriptional signature, plus distinct inflammatory responses that vary between reproductive cycle phases

BackgroundThe emergence of fully antimicrobial resistant Neisseria gonorrhoeae has led global public health agencies to identify a critical need for next generation anti-gonococcal pharmaceuticals. The development and success of these compounds will rely upon valid pre-clinical models of gonorrhoeae infection. We recently developed and reported the first model of upper genital tract gonococcal infection. During initial characterization, we observed significant reproductive cycle-based variation in infection outcome. When uterine infection occurred in the diestrus phase, there was significantly greater pathology than during estrus phase. The aim of this study was to evaluate transcriptional profiles of infected uterine tissue from mice in either estrus or diestrus phase in order to elucidate possible mechanisms for these differences.ResultsGenes and biological pathways with phase-independent induction during infection showed a chemokine dominant cytokine response to Neisseria gonorrhoeae. Despite general induction being phase-independent, this common anti-gonococcal response demonstrated greater induction during diestrus phase infection. Greater activity of granulocyte adhesion and diapedesis regulators during diestrus infection, particularly in chemokines and diapedesis regulators, was also shown. In addition to a greater induction of the common anti-gonococcal response, Gene Set Enrichment Analysis identified a diestrus-specific induction of type-1 interferon signaling pathways.ConclusionsThis transcriptional analysis of murine uterine gonococcal infection during distinct points in the natural reproductive cycle provided evidence for a common anti-gonococcal response characterized by significant induction of granulocyte chemokine expression and high proinflammatory mediators. The basic biology of this host response to N. gonorrhoeae in estrus and diestrus is similar at the pathway level but varies drastically in magnitude. Overlaying this, we observed type-1 interferon induction specifically in diestrus infection where greater pathology is observed. This supports recent work suggesting this pathway has a significant, possibly host-detrimental, function in gonococcal infection. Together these findings lay the groundwork for further examination of the role of interferons in gonococcal infection. Additionally, this work enables the implementation of the diestrus uterine infection model using the newly characterized host response as a marker of pathology and its prevention as a correlate of candidate vaccine efficacy and ability to protect against the devastating consequences of N. gonorrhoeae-associated sequelae.