Physiologic role of interleukin-1 receptor antagonist

Impact of dual neutralization of TNF-α and IL-1β along with Gentamicin treatment on the functions of blood and splenic neutrophils and its role on improvement of S. aureus induced septic arthritis

Researches of recent past years have emphasized potential of antibiotics to improve septic arthritis but as multi-drug resistant strains like MRSA are emerging fast, new alternative therapeutic advances are high in demand. This study aims to figure out the role of neutrophils in regulating inflammatory responses of S. aureus induced septic arthritis while using TNF-α Ab or IL-1β Ab along with antibiotic gentamicin or both in combination. In this study, role of anti-oxidant enzymes were investigated and correlated with generated ROS level. While expression of TLR2, TNFR2, MMP2, RANKL, SAPK/JNK in the spleen were evaluated through western blot. Serum activity of IL-8, IL-10, IL-12, OPG, OPN, CRP was assessed using ELISA. Flow cytometry study evaluated inflamed neutrophil population. Results have shown TNF-α neutralization along with gentamicin was able to reduce arthritic swelling prominently. While combination therapy effectively reduced blood neutrophil ROS activity, arginase activity, MPO activity along with spleen bacterial burden. Serum OPG, CRP, IL-10 level got reduced while serum OPN, IL-8 and IL-12 level enhanced in treatment groups, showing mitigation of inflammatory damage. Overall, it is a novel work that observed how antibiotic and antibody therapy enhanced neutrophil function positively to combat sepsis. This study may not be fully applicable in clinical trials as it is performed with animal model. Clinical trials include crystalline and inflammatory arthritides, trauma, neoplasm. Interdisciplinary collaboration between radiology, orthopaedic surgery and knowledge of animal system responses may give better idea to find proper therapeutic approach in future research works.

Effect of knife castration on leukocyte cytokine expression and indicators of stress, pain, and inflammation in Korean cattle bull calves

OBJECTIVE

This study investigated the effects of surgical castration on behavior, physiological and inflammatory indicators, and leukocyte cytokine mRNA levels in Korean cattle bull calves.

METHODS

Nineteen Korean cattle bull calves (average body weight, 254.5 kg; average age, 8.2 months) were divided into two treatment groups: control (n = 9) and castration (n = 10). Surgical castration was performed using Newberry knives and a Henderson castrating tool. Blood was obtained just before castration (0 h) and at 0.5 h, 6 h, 1 d, 3 d, 7 d, and 14 d after castration. Plasma cortisol (PC), saliva cortisol (SC), plasma substance P, and plasma haptoglobin concentrations, and the leucocyte mRNA levels of the interleukin-1-alpha (IL1A), interleukin-1-beta (IL1B), interleukin-1 receptor antagonist (IL1RN), and interleukin-6 (IL6) genes were analyzed.

RESULTS

Castration decreased (p<0.01) the average daily gain and gain/feed ratio. Castration reduced the time spent eating (p<0.001) and the eating frequency (p<0.01) and increased (p<0.001) the lying frequency. Castration temporarily increased (p<0.05) circulating PC and SC concentrations at 0.5 h after castration. Castration temporarily increased (p<0.05) plasma substance P concentrations at 1 d after castration. Castration increased (p<0.05) plasma haptoglobin concentrations at 1 and 3 d after castration. Castration increased (p< 0.05) leukocyte mRNA levels of the IL1A, IL1B, IL1RN, and IL6 genes at 6 h after castration.

CONCLUSION

Castration temporarily induced stress and expression of leucocyte inflammatory cytokine genes in Korean cattle bull calves.

Changes in novel anti-infalmmatory cytokine concetration in the bood of endurance and race horses at different levels of training

Several anti-inflammatory cytokines have been proposed as markers for exercise monitoring in humans such as the interleukin 1 receptor agonist (IL-ra), or interleukin 13 (IL-13). Equine athletes may be considered a model for human exercise physiology research, however there is a lack of such studies of this species. Thus, we decided to examine the changes of IL-1ra and IL-13 in serum concentration during aerobic (endurance) and anaerobic (race) exercise in horses of different fitness levels in comparison with the well-known anti-inflammatory cytokine interleukin 10 (IL-10). The group of endurance horses (n = 13) consisted of animals competing over 100 (n = 7) and 120 km (n = 6) rides. The group of racehorses (n = 18) consisted of trained (n = 9) and untrained (n = 9) animals. The blood samples were obtained before and after the exercise. The ELISA test was performed to evaluate the changes of IL-1ra, IL-13 and IL-10 during different types of exercise. In endurance horses there was an increase in IL-13 (p = 0.0012) after the 100 km ride and in IL-1ra (p = 0.0411) after the 120 km ride. In race horses there was a higher IL-13 basal serum concentration in the untrained group, as well as a decrease of IL-13 after exercise (p = 0.0188). In trained racehorses there was an increase in IL-1ra (p < 0.0001) and IL-13 after exercise (p = 0.0028). In conclusion, the reaction of IL-1ra and IL-13 to different types of exercise differ from each other. Thus, in future, they may be helpful in monitoring the fitness of horses, however more research is needed.

Single-cell RNA sequencing analysis revealed cellular and molecular immune profiles in lung squamous cell carcinoma

Although breakthroughs have been made in the treatment of non-small cell lung cancer, there are only a few choices for advanced-stage or recurrent lung squamous cell carcinoma (LUSC) patients. In our study, we identified 7 major cell types in thedepicted the immunolandscape of LUSC microenvironment using single-cell RNA sequencing. We found that an immunosuppressive receptor, T cell immunoglobulin and immunoreceptor tyrosine-based inhibitory motif domain (TIGIT), was highly expressed by regulatory T cells (Tregs) and exhausted CD8⁺T cells, suggesting that upregulation of TIGIT might promote an immunosuppressive microenvironment and inhibit the cytotoxic ability of CD8⁺T cells. We also identified tumor-associated neutrophil (TAN), characterized by CXCR2, CSF3R and CXCL8, in the tumor region, and TANs upregulated the expression of interleukin 1 receptor antagonist (IL1RN) which suggested that TAN might exert an immunosuppressive role via expressing IL1RN. Furthermore, the number of SPP1+ macrophages(SPP1⁺M) significantly increased in tumor microenvirnment, which was correlated with the poor survival of patients. Additionally, regulatory networks based on SPP1⁺M revealed that the disparities of several ligand-receptor pairs existed between tumor and normal tissues. Among these pairs, SPP1-CD44 showed the most interactions between SPP1⁺M and other cell types. Our results provided deep insight into the immune landscape of LUSC and an essential resource for drug discovery in the future.

The past, present, and future of immunotherapy for bladder tumors

Bladder cancer is a prominent cancer worldwide with a relatively low survival rate for patients with increased stage and metastasis. Current treatments are based on surgical removal, bacillus Calmette-Guerin (BCG) Immunotherapy, and platinum-based chemotherapy. However, treatment resistance due to genetic instability of bladder tumors, as well as intolerance to treatment adverse effects leads to the necessity to further treatment options. New advancements in immunotherapy are on the rise for treatment of various cancers and specifically has shown promise in the treatment of bladder cancer. This review summarizes these new advancements in treatment options involving cytokines and cytokine blockade. Such a study might be helpful for urologists to manage patients with bladder cancer more effectively.

Canakinumab for the treatment of autoinflammatory very early onset- inflammatory bowel disease

Introduction

Therapeutic options are critically needed for children with refractory very early onset inflammatory bowel disease (VEO-IBD). Our aim was to evaluate clinical response to canakinumab, an anti-IL-1β monoclonal antibody, in patients with VEO-IBD whose phenotype resembles those with monogenic autoinflammatory disease.

Methods

This is a single center retrospective study of patients with VEO-IBD with autoinflammatory phenotype (AIP) in the absence of identified monogenic disease treated with canakinumab for >6 months. AIP was defined as confirmed IBD with associated signs of systemic inflammation in the absence of infection, including leukocytosis, markedly elevated inflammatory markers, and extraintestinal manifestations (recurrent fevers, oral ulcers, arthritis). Primary outcomes included clinical response in disease activity indices after 6 months of therapy. Secondary outcomes included rate of AIP signs and symptoms, growth, surgery, steroid use, hospitalizations, and adverse events.

Results

Nineteen patients were included: 47% with infantile onset, 58% classified as IBD-U, and 42% classified as CD. At baseline, 37% were biologic naïve, and canakinumab was used as dual therapy in 74% of patients. Clinical response was achieved in 89% with statistically significant improvement in PCDAI and PUCAI. Clinical remission was achieved in 32% of patients. There was significant improvement in the clinical manifestations of AIP and the biochemical markers of disease. Number of hospitalizations (p<0.01) and length of stay (p<0.05) decreased. Growth improved with median weight-for-length Z-score increasing from -1.01 to 1.1 in children less than 2 years old. There were minimal adverse events identified during the study period.

Conclusion

Canakinumab may be an effective and safe treatment for a subset of children with VEO-IBD with AIP, as well as older patients with IBD. This study highlights the importance of a precision medicine approach in children with VEO-IBD.

Interleukin-1 genetic polymorphisms in knee osteoarthritis: What do we know? A meta-analysis and systematic review

PURPOSE

Interleukin-1 is the main proinflammatory cytokine in osteoarthritis (OA). Several single-nucleotide polymorphisms (SNPs) within the IL-1 gene cluster (IL-1β, IL-1R1, and IL-1RN) have been determined, but their associations with knee OA remain poorly understood. The present study aimed to identify the associations between IL-1 SNPs and knee osteoarthritis.

METHODS

This meta-analysis and systematic review included all comparative studies published in the MEDLINE/PubMed, Embase, Google Scholar, and Cochrane Library databases. We performed a systematic search to identify relevant studies on the evaluation of the correlation between the IL-1 gene and knee OA published up to February 2020 that met the eligibility criteria. Nine studies on a total of 2256 knees with OA and 3527 healthy knees met the eligibility criteria. Results associated with IL-1A, IL-1B, IL-1R1, and IL-1RN SNPs were extracted and compared between knees with OA and healthy knees. Methodological quality was assessed using the Newcastle-Ottawa scale (NOS). All studies with fair or good quality were included.

RESULTS

The meta-analysis showed that the risk of knee OA is decreased by the IL-1RN*1 and IL-1RN*1/*1 genotypes and increased by the IL-1RN*2 and I-L1RN*1/*2 genotypes. The systematic review revealed only two studies associating the IL-1RN allele, none associating the IL-1B polymorphism, and only one study associating IL-1A and IL-1R1 polymorphisms with knee OA.

CONCLUSIONS

Several IL-1RN alleles and genotypes play a role in knee OA but other genetic variations in the IL-1 region were still conflicting in its association with knee OA.

Oral Dysbiosis and Inflammation in Parkinson's Disease

Background:

Oral microbiota has largely escaped attention in Parkinson’s disease (PD), despite its pivotal role in maintaining oral and systemic health.

Objective:

The aim of our study was to examine the composition of the oral microbiota and the degree of oral inflammation in PD.

Methods:

Twenty PD patients were compared to 20 healthy controls. Neurological, periodontal and dental examinations were performed as well as dental scaling and gingival crevicular fluid sampling for cytokines measurement (interleukine (IL)-1β, IL-6, IL-1 receptor antagonist (RA), interferon-γ and tumor necrosis factor (TNF)-α). Two months later, oral microbiota was sampled from saliva and subgingival dental plaque. A 16S rRNA gene amplicon sequencing was used to assess bacterial communities.

Results:

PD patients were in the early and mid-stage phases of their disease (Hoehn & Yahr 2–2.5). Dental and periodontal parameters did not differ between groups. The levels of IL-1β and IL-1RA were significantly increased in patients compared to controls with a trend for an increased level of TNF-α in patients. Both saliva and subgingival dental plaque microbiota differed between patients and controls. Streptococcus mutans, Kingella oralis, Actinomyces AFQC_s, Veillonella AFUJ_s, Scardovia, Lactobacillaceae, Negativicutes and Firmicutes were more abundant in patients, whereas Treponema KE332528_s, Lachnospiraceae AM420052_s, and phylum SR1 were less abundant.

Conclusion:

Our findings show that the oral microbiome is altered in early and mid-stage PD. Although PD patients had good dental and periodontal status, local inflammation was already present in the oral cavity. The relationship between oral dysbiosis, inflammation and the pathogenesis of PD requires further study.

Intestinal and enthesis innate immunity in early axial spondyloarthropathy

Axial SpA (axSpA), encompassing AS, is a multifactorial disease that localizes to sites of high spinal biomechanical stress. Much has been written on T cells and adaptive immunity in axSpA, which is understandable given the very strong HLA-B27 disease association. Extra-axial disease characteristically involves the anterior uveal tract, aortic root, lung apex and terminal ileum. Under recent classification, axSpA is classified as an intermediate between autoimmunity and autoinflammatory disease, with the latter term being synonymous with innate immune dysregulation. The purpose of this review is to evaluate the ‘danger signals’ from both the exogenous intestinal microbiotal adjuvants or pathogen-associated molecular patterns that access the circulation and endogenously derived damaged self-tissue or damage-associated molecular patterns derived from entheses and other sites of high biomechanical stress or damage that may serve as key drivers of axSpA onset, evolution, disease flares and eventual outcomes.

RNA-Seq Transcriptome Analysis Reveals Long Terminal Repeat Retrotransposon Modulation in Human Peripheral Blood Mononuclear Cells after In Vivo Lipopolysaccharide Injection

Human endogenous retroviruses (HERVs) and mammalian apparent long terminal repeat (LTR) retrotransposons (MaLRs) are retroviral sequences that integrated into germ line cells millions of years ago. Transcripts of these LTR retrotransposons are present in several tissues, and their expression is modulated in pathological conditions, although their function remains often far from being understood. Here, we focused on the HERV/MaLR expression and modulation in a scenario of immune system activation. We used a public data set of human peripheral blood mononuclear cells (PBMCs) RNA-Seq from 15 healthy participants to a clinical trial before and after exposure to lipopolysaccharide (LPS), for which we established an RNA-Seq workflow for the identification of expressed and modulated cellular genes and LTR retrotransposon elements.IMPORTANCE We described the HERV and MaLR transcriptome in PBMCs, finding that about 8.4% of the LTR retrotransposon loci were expressed and identifying the betaretrovirus-like HERVs as those with the highest percentage of expressed loci. We found 4,607 HERV and MaLR loci that were modulated as a result of in vivo stimulation with LPS. The HERV-H group showed the highest number of differentially expressed most intact proviruses. We characterized the HERV and MaLR loci as differentially expressed, checking their genomic context of insertion and observing a general colocalization with genes that are involved and modulated in the immune response, as a consequence of LPS stimulation. The analyses of HERV and MaLR expression and modulation show that these LTR retrotransposons are expressed in PBMCs and regulated in inflammatory settings. The similar regulation of HERVs/MaLRs and genes after LPS stimulation suggests possible interactions of LTR retrotransposons and the immune host response.

IL-1Rahigh-IL-4low-IL-13low: A Novel Plasma Cytokine Signature Associated with Olfactory Dysfunction in Older US Adults

Inflammation has been implicated in physical frailty, but its role in sensory impairment is unclear. Given that olfactory impairment predicts dementia and mortality, determining the role of the immune system in olfactory dysfunction would provide insights mechanisms of neurosensory decline. We analyzed data from the National Social Life, Health and Aging Project, a representative sample of home-dwelling older US adults. Plasma levels of 18 cytokines were measured using standard protocols (Luminex xMAP). Olfactory function was assessed with validated tools (n-butanol sensitivity and odor identification, each via Sniffin' Sticks). We tested the association between cytokine profiles and olfactory function using multivariate ordinal logistic regression, adjusting for age, gender, race/ethnicity, education level, cognitive function, smoking status, and comorbidity. Older adults with the IL-1Rahigh-IL-4low-IL-13low cytokine profile had worse n-butanol odor sensitivity (odds ratio [OR] = 1.61, 95% confidence interval [CI] 1.19-2.17) and worse odor identification (OR = 1.42, 95% CI 1.11-1.80). Proinflammatory, Th1, or Th2 cytokine profiles were not associated with olfactory function. Moreover, accounting for physical frailty did not alter the main findings. In conclusion, we identified a plasma cytokine signature-IL-1Rahigh-IL-4low-IL-13low-that is associated with olfactory dysfunction in older US adults. These data implicate systemic inflammation in age-related olfactory dysfunction and support a role for immune mechanisms in this process, a concept that warrants additional scrutiny.

Quantitative assessment of extracellular IL-1 regulation

IL-1 system is involved in the induction and maintenance of chronic inflammation associated with several autoimmune diseases and cancer, mainly due to its capacity to promote the secretion of inflammatory mediators. For this reason, several intracellular and extracellular mechanisms for this system have been fixed during the evolution. In spite of the large description of molecular interactions between IL-1 ligands and receptors, little is known about the relevance and limits of the extracellular regulatory mechanims in different scenarios. To tackle this problem, we developed and calibrated a mathematical model including all the known interactions between IL-1 ligands and IL-1Rs and calibrate it with experimental data of IL-1 binding to different cells. The model predicts that, independently on the IL-1Rs expression, IL-1α has more ability than IL-1β to induce IL-1 signaling, which suggests that both ligands can be equally relevant for the IL-1 related inflammation. On the other hand, at the cell level, IL-1 signaling is mainly controlled by IL-1R1 and IL-1R3 and not by IL-1R2. Moreover, the soluble form of IL-1R1 and IL-1RA have the highest capacity to prevent IL-1α while IL-1R2 and IL-1R1 and IL-1RA have a similar capacity to prevent IL-1β signaling. The soluble IL-1R3 has the lowest capacity to prevent IL-1 signaling and preferentially inhibits cells with low number of IL-1R3. In general, model predictions suggest several ways in which IL-1 controlling system may fail, developing IL-1 related inflammation.

Proteomic Biomarkers of Retinal Inflammation in Diabetic Retinopathy

Diabetic retinopathy (DR), a sight-threatening neurovasculopathy, is the leading cause of irreversible blindness in the developed world. DR arises as the result of prolonged hyperglycemia and is characterized by leaky retinal vasculature, retinal ischemia, retinal inflammation, angiogenesis, and neovascularization. The number of DR patients is growing with an increase in the elderly population, and therapeutic approaches are limited, therefore, new therapies to prevent retinal injury and enhance repair are a critical unmet need. Besides vascular endothelial growth factor (VEGF)-induced vascular proliferation, several other mechanisms are important in the pathogenesis of diabetic retinopathy, including vascular inflammation. Thus, combining anti-VEGF therapy with other new therapies targeting these pathophysiological pathways of DR may further optimize treatment outcomes. Technological advancements have allowed for high-throughput proteomic studies examining biofluids such as aqueous humor, vitreous humor, tear, and serum. Many DR biomarkers have been identified, especially proteins involved in retinal inflammatory processes. This review attempts to summarize the proteomic biomarkers of DR-associated retinal inflammation identified over the last several years.

Inflammatory cytokines in bladder cancer

The presence of inflammatory cells and their products in the tumor microenvironment plays a crucial role in the pathogenesis of a tumor. Releasing the cytokines from a host in response to infection and inflammation can inhibit tumor growth and progression. However, tumor cells can also respond to the host cytokines with increasing the growth/invasion/metastasis. Bladder cancer (BC) is one of the most common cancers in the world. The microenvironment of a bladder tumor has been indicated to be rich in growth factors/inflammatory cytokines that can induce the tumor growth/progression and also suppress the immune system. On the contrary, modulate of the cancer progression has been shown following upregulation of the cytokines-related pathways that suggested the cytokines as potential therapeutic targets. In this study, we provide a summary of cytokines that are involved in BC formation/regression with both inflammatory and anti-inflammatory properties. A more accurate understanding of tumor microenvironment creates favorable conditions for cytokines targeting to treat BC.

Effects of blood-derived products and sodium hyaluronate on equine synovial fluid cells and on synovial fluid from osteochondrotic joints of horses after arthroscopy and administration of treatment

OBJECTIVE

To compare effects of platelet-rich plasma (PRP), interleukin-1 receptor antagonist protein (IRAP), autologous processed plasma (APP), and sodium hyaluronate treatments on synovial fluid cells in vitro and on synovial fluid obtained from osteochondrotic joints of horses.

SAMPLE

Synovial fluid cells from 8 healthy equine tibiotarsal joints (in vitro experiment) and synovial fluid samples from 40 tibiotarsal joints of 25 horses with osteochondrosis dissecans (in vivo experiment).

PROCEDURES

Effects of various treatments on concentrations of prostaglandin (PG) E₂, interleukin (IL)-1β, tumor necrosis factor-α, IL-10, and IL-1 receptor antagonist (IL-1ra) were analyzed in cell medium supernatant, and production of reactive oxygen species was analyzed by use of flow cytometry. In an in vivo experiment, synovial fluid samples were collected before and 48 hours after arthroscopy and treatment administration (8 joints/treatment) and evaluated to determine concentrations of hyaluronic acid, chondroitin sulfate, PGE₂, tumor necrosis factor-α, IL-1, IL-10, and IL-1ra.

RESULTS

All in vitro treatments reduced reactive oxygen species production, PRP increased PGE₂ concentrations, and PRP, IRAP, and APP increased IL-1ra concentrations. Only IRAP and APP increased IL-1 concentrations. For the in vivo experiment, PRP increased and IRAP decreased PGE₂ concentrations in synovial fluid after arthroscopy. All treatments increased IL-1ra concentrations, but only sodium hyaluronate resulted in a significant increase in concentration, compared with the concentration for untreated joints. Also, IRAP reduced hyaluronic acid breakdown in synovial fluid.

CONCLUSIONS AND CLINICAL RELEVANCE

PRP should be used with caution in the period immediately after arthroscopy and treatment of osteochondrotic joints of horses. All treatments had antioxidant effects. Sodium hyaluronate, APP, and IRAP might help ameliorate joint inflammation.

Pulmonary fibroblasts-secreted CXCL10 polarizes alveolar macrophages under pro-inflammatory stimuli

BACKGROUND

During acute lung injury, lung fibroblasts produce chemokines that assist the activation and migration of resident macrophages. The interactions between pulmonary fibroblasts and alveolar macrophages demonstrate the early event in the recruitment of immune cells, and the production of chemokines appear to be central mediators of the initiation and progression of inflammatory responses. In this study, the aim was to investigate the signaling pathway leading to CXCL10 secretion and the effects of CXCL10 released by activated fibroblasts on regulating macrophage polarization in a pro-inflammatory microenvironment.

METHODS

The expression of chemokines CCL2, CCL5, CXCL10, and CXCL12, and the phosphorylation of signaling molecules STAT3, FAK, GSK3αβ and PKCδ were investigated by real time-PCR, ELISA, or Western blot on TNFα- or IL-1β-activated MRC-5 pulmonary fibroblasts. By collecting conditioned medium from TNFα-activated fibroblasts, the expression of iNOS and arginase I on MH-S alveolar macrophages were examined by real-time PCR. Surface markers CD86 and CD206 expressions on alveolar macrophages were also evaluated by flow cytometry.

RESULTS

We found that CXCL10 production was significantly elevated on MRC-5 fibroblasts under TNFα- or IL-1β treatment. In addition, we revealed that TNFα and IL-1β initiated phosphorylation of STAT3, FAK, GSK3αβ and PKCδ signaling cascade, leading to the elevation of CXCL10 expression. Moreover, conditioned medium collected from TNFα-activated MRC-5 fibroblasts increased iNOS and CD86 expressions and decreased arginase I and CD206 expressions on MH-S alveolar macrophages, and neutralization of CXCL10 abolished these observed phenomena.

CONCLUSION

These results suggest that CXCL10 is crucial in activated fibroblasts-promoted M1 phenotype polarization of alveolar macrophages. In this regard, targeting fibroblasts-released CXCL10 may be promising as anti-inflammatory therapy against acute lung injury.

Upregulation of IL-1 Receptor Antagonist in a Mouse Model of Migraine

Migraine is a disorder characterized by attacks of monolateral headaches, often accompanied by nausea, vomiting, and photophobia. Around 30% of patients also report aura symptoms. The cause of the aura is believed to be related to the cortical spreading depression (CSD), a wave of neuronal and glial depolarization originating in the occipital cortex, followed by temporary neuronal silencing. During a migraine attack, increased expression of inflammatory mediators, along with a decrease in the expression of anti-inflammatory genes, have been observed. The aim of this study was to evaluate the expression of inflammatory genes, in particular that of IL-1 receptor antagonist (IL-1RN), following CSD in a mouse model of familial hemiplegic migraine type 1 (FHM-1). We show here that the expression of IL-1RN was upregulated after the CSD, suggesting a possible attempt to modulate the inflammatory response. This study allows researchers to better understand the development of the disease and aids in the search for new therapeutic strategies in migraine.

Accumulation of Cytoplasmic DNA Due to ATM Deficiency Activates the Microglial Viral Response System with Neurotoxic Consequences

ATM (ataxia-telangiectasia mutated) is a PI3K-like kinase best known for its role in the DNA damage response (DDR), especially after double-strand breaks. Mutations in the ATM gene result in a condition known as ataxia-telangiectasia (A-T) that is characterized by cancer predisposition, radiosensitivity, neurodegeneration, sterility, and acquired immune deficiency. We show here that the innate immune system is not spared in A-T. ATM-deficient microglia adopt an active phenotype that includes the overproduction of proinflammatory cytokines that are toxic to cultured neurons and likely contribute to A-T neurodegeneration. Causatively, ATM dysfunction results in the accumulation of DNA in the cytoplasm of microglia as well as a variety of other cell types. In microglia, cytoplasmic DNA primes an antiviral response via the DNA sensor, STING (stimulator of interferon genes). The importance of this response pathway is supported by our finding that inhibition of STING blocks the overproduction of neurotoxic cytokines. Cytosolic DNA also activates the AIM2 (absent in melanoma 2) containing inflammasome and induces proteolytic processing of cytokine precursors such as pro-IL-1β. Our study furthers our understanding of neurodegeneration in A-T and highlights the role of cytosolic DNA in the innate immune response.SIGNIFICANCE STATEMENT Conventionally, the immune deficiencies found in ataxia-telangiectasia (A-T) patients are viewed as defects of the B and T cells of the acquired immune system. In this study, we demonstrate the microglia of the innate immune system are also affected and uncover the mechanism by which this occurs. Loss of ATM (ataxia-telangiectasia mutated) activity leads to a slowing of DNA repair and an accumulation of cytoplasmic fragments of genomic DNA. This ectopic DNA induces the antivirus response, which triggers the production of neurotoxic cytokines. This expands our understanding of the neurodegeneration found in A-T and offers potentially new therapeutic options.

The Neutrophil’s Role During Health and Disease

Neutrophils have always been considered as uncomplicated front-line troopers of the innate immune system equipped with limited proinflammatory duties. Yet recently, the role of the neutrophil has been undergoing a rejuvenation of sorts. Neutrophils are now considered complex cells capable of a significant array of specialized functions, and as an effector of the innate immune response, they are able to regulate many processes such as acute injury and repair, cancer, autoimmunity, and chronic inflammatory processes. Furthermore, evidence exists to indicate that neutrophils also contribute to adaptive immunity by aiding the development of specific adaptive immune responses or guiding the subsequent adaptive immune response. With this revived interest in neutrophils and their many novel functions, it is prudent to review what is currently known about neutrophils and, even more importantly, understand what information is lacking. We discuss the essential features of the neutrophil, from its origins, lifespan, subsets, margination and sequestration of the neutrophil to the death of the neutrophil. We highlight neutrophil recruitment to both infected and injured tissues and outline differences in recruitment of neutrophils between different tissues. Finally, we examine how neutrophils use different mechanisms to either bolster protective immune responses or negatively cause pathological outcomes at different locations.

Pharmacokinetics and Safety of Recombinant Human Interleukin-1 Receptor Antagonist GR007 in Healthy Chinese Subjects

Background and Objectives

The recombinant human interleukin-1 receptor antagonist (rhIL-1Ra) GR007 is a candidate drug with the potential to prevent the toxicity induced by chemotherapy agents by blocking the IL-1 signaling pathway. The aim of this study was to assess the pharmacokinetics and safety of GR007 in healthy Chinese subjects.

Methods

Thirty subjects received a single intramuscular injection of 30 mg (n = 10), 90 mg (n = 10), or 150 mg (n = 10) GR007. After administration, the pharmacokinetic characteristics and safety were evaluated.

Results

No serious adverse events were reported in this study, and the adverse events reported showed no dose dependency. Pharmacokinetic analysis showed that the median time to maximum concentration (T_max) of GR007 in the three groups was between 2.75 and 4.00 h and the geometric mean elimination half-life (T_1/2) for each group was 2.38, 2.22, and 3.29 h, respectively. The area under the concentration vs time curve (AUC), but not the maximum concentration (C_max), increased in a dose-proportional manner.

Conclusions

The results showed that a single intramuscular injection of 30–150 mg GR007 had good safety and tolerability in healthy Chinese subjects. The results of the evaluation of the safety and pharmacokinetics of GR007 performed in this study support its use as a repeated daily injection in ongoing clinical trials focusing on patients with cancer.

Eosinophils Accelerate Pathogenesis of Psoriasis by Supporting an Inflammatory Milieu that Promotes Neutrophil Infiltration

Eosinophils are proinflammatory granulocytes that are involved in the pathogenesis of various inflammatory reactions. However, their roles in psoriasis remain largely unknown. In this study, by examining the inflammatory features of the eosinophilic cell line EoL-1 and an imiquimod-induced murine model of psoriasis, we show that eosinophils provide inflammatory signals that accelerate the pathogenesis of psoriasis. EoL-1 cells constitutively expressed TLR7, which mediates acute and rapidly developing psoriatic inflammation. The activation of TLR7 on EoL-1 cells using R837 resulted in the secretion of inflammatory mediators that support the migration, activation, and survival of neutrophils. The underlying pathologic role of eosinophils in psoriatic inflammation was further substantiated by markedly decreased psoriasiform inflammation in imiquimod-treated ΔdblGATA mice, which have a systemic eosinophil deficiency. While imiquimod-treated wild-type mice showed a significant increase in the eosinophils in their skin, neutrophils remarkably outnumbered the eosinophils in the skin, lymph nodes, and spleen in wild-type mice after imiquimod application. In addition, lesional skin samples from psoriasis patients also showed up-regulated eosinophil cytotoxic granules, accompanied by marked neutrophil infiltration. Based on these collective data, we propose that eosinophils accelerate psoriatic inflammation by supporting inflammatory microenvironments to favor the activation and infiltration of neutrophils.

A novel and less invasive technique to assess cytokine profile of vitreous in patients of diabetic macular oedema

PurposeA pilot study to validate the collection of vitreous reflux (VR) after intravitreal injection using Schirmers tear strips was carried out. We assessed its efficiency for proteomics studies by estimating the differential expression of 27 cytokines using multiplexed bead array in diabetic macular oedema and proliferative diabetic retinopathy. To set, validate and assess the efficacy of Schirmer tear strips for collecting VR in patients undergoing intravitreal injections for diabetic macular oedema (DME).Patients and methodsVR samples were collected from 11 eyes of DME patients after intravitreal injections using Schirmer tear strips. Undiluted vitrectomy samples were obtained from six eyes of non-diabetic patients with idiopathic macular hole and seven eyes of diabetic patients with high-risk proliferative diabetic retinopathy (Hr-PDR), which were also subsampled on the Schirmer tear strips. Tear sampling was done in a subset of the DME patients. Total protein concentration between VR and vitrectomy samples was compared. Levels of the set of 27 cytokines in Schirmer tear strips samples were measured. Inter-group comparison for cytokines was done using Mann-Whitney U-test.ResultsSimilar protein concentration in VR samples and vitrectomy samples (P<0.05) was obtained. Tear protein contamination was not detected in VR samples. In comparison with no-DR patients, 25 and 20 of the measured 27 cytokines were significantly elevated (P<0.05) in the Hr-PDR and DME patients, respectively. As compared with no-DR patients, vascular endothelial growth factor was only moderately elevated in DME patients (P>0.05), but significantly elevated in Hr-PDR patients (P<0.05). Interleukin 1 receptor antagonist/interleukin 1b (IL1RA/IL1b) ratio was 13 times higher in DME patients as compared with Hr-PDR group.ConclusionWe demonstrated a simple, safe method of VR sampling. This technique provides a pure, albeit small, vitreous sample for proteomics. IL1RA/IL1b ratio was found to be 13-fold higher in the DME group as compared to the Hr-PDR.

Circulating Levels of Interleukin 1-Receptor Antagonist and Risk of Cardiovascular Disease

Objective—

Interleukin (IL)-1β represents a key cytokine in the development of cardiovascular disease (CVD). IL-1β is counter-regulated by IL-1 receptor antagonist (IL-1RA), an endogenous inhibitor. This study aimed to identify population-based studies on circulating IL-1RA and incident CVD in a systematic review, estimate the association between IL-1RA and incident CVD in a meta-analysis, and to test whether the association between IL-1RA and incident CVD is explained by other inflammation-related biomarkers in the MONICA/KORA Augsburg case–cohort study (Multinational Monitoring of Trends and Determinants in Cardiovascular Disease/Cooperative Health Research in the Region of Augsburg).

Approach and Results—

We performed a systematic literature search and identified 5 cohort studies on IL-1RA and incident CVD in addition to the MONICA/KORA Augsburg case–cohort study for a meta-analysis based on a total of 1855 CVD cases and 18 745 noncases with follow-up times between 5 and 16 years. The pooled standardized hazard ratio (95% confidence interval) for incident CVD was 1.11 (1.06–1.17) after adjustment for age, sex, anthropometric, metabolic, and lifestyle factors ( P <0.0001). There was no heterogeneity in effect sizes (I 2 =0%; P =0.88). More detailed analyses in the MONICA/KORA study showed that the excess risk for CVD was attenuated by ≥10% after additional separate adjustment for serum levels of high-sensitivity C-reactive protein, IL-6, myeloperoxidase, soluble E-selectin, or soluble intercellular adhesion molecule-1.

Conclusions—

Serum IL-1RA levels were positively associated with risk of CVD after adjustment for multiple confounders in a meta-analysis of 6 population-based cohorts. This association may at least partially reflect a response to triggers inducing subclinical inflammation, oxidative stress, and endothelial activation.

Cytokine and Growth Factor Concentrations in Canine Autologous Conditioned Serum

OBJECTIVE

To compare cytokine and growth factor concentrations in canine autologous conditioned serum (ACS) to canine plasma.

STUDY DESIGN

Experimental in vivo study.

ANIMALS

Client-owned, adult dogs (n=22).

METHODS

Blood collected from 16 medium to large breed dogs was used to produce ACS (Orthokine(®) vet irap 10 syringes) and citrated plasma (control). Canine-specific ELISA assays were run per manufacturers' instructions for interleukin (IL)-10, IL-4, tumor necrosis factor (TNF)-α, insulin-like growth factor (IGF)-1, fibroblast growth factor (FGF)-2, transforming growth factor (TGF)-β1, IL-1β, and interleukin-1 receptor antagonist (IL-1ra). Serum, in addition to plasma and ACS, was collected from an additional 6 dogs for TNF-α, IL-1β, and IL-1ra analysis (total of 22 dogs). Data were analyzed for differences in each cytokine concentration using pairwise comparisons between ACS, plasma, and serum using Wilcoxon signed-rank tests. Significance was set at P<.05.

RESULTS

There was a large variability in growth factor and cytokine concentrations in ACS and plasma for individual dogs. There were no significant differences in IL-10, TNF-α, IGF-1, FGF-2, and TGF-β1 concentrations between ACS, plasma, and serum. The IL-1β concentrations in ACS (median, range 46.3 pg/mL, 0-828.8) and IL-4 (0.0 pg/mL, 0-244.1) were significantly higher than plasma (36.6 pg/mL, 0-657.1 and 0.0 pg/mL, 0-0, respectively). The IL-1ra concentration in ACS (median, range 3,458.9 pg/mL, 1,243.1-12,089.0) was significantly higher than plasma (692.3 pg/mL, 422.5-1,475.6). The IL-1ra:IL-1β ratio in ACS was significantly higher than plasma (39.9 vs. 7.2).

CONCLUSION

IL-1ra concentrations in canine ACS were comparable to those published for people and horses and pro-inflammatory cytokines remained low in canine ACS.

A novel approach for emerging and antibiotic resistant infections: Innate defense regulators as an agnostic therapy

Innate Defense Regulators (IDRs) are short synthetic peptides that target the host innate immune system via an intracellular adaptor protein which functions at key signaling nodes. In this work, further details of the mechanism of action of IDRs have been discovered. The studies reported here show that the lead clinical IDR, SGX94, has broad-spectrum activity against Gram-negative and Gram-positive bacterial infections caused by intracellular or extracellular bacteria and also complements the actions of standard of care antibiotics. Based on in vivo and primary cell culture studies, this activity is shown to result from the primary action of SGX94 on tissue-resident cells and subsequent secondary signaling to activate myeloid-derived cells, resulting in enhanced bacterial clearance and increased survival. Data from non-clinical and clinical studies also show that SGX94 treatment modulates pro-inflammatory and anti-inflammatory cytokine levels, thereby mitigating the deleterious inflammatory consequences of innate immune activation. Since they act through host pathways to provide both broad-spectrum anti-infective capability as well as control of inflammation, IDRs are unlikely to be impacted by resistance mechanisms and offer potential clinical advantages in the fight against emerging and antibiotic resistant bacterial infections.

Cell-Based Therapy for Silicosis

Silicosis is the most common pneumoconiosis globally, with higher prevalence and incidence in developing countries. To date, there is no effective treatment to halt or reverse the disease progression caused by silica-induced lung injury. Significant advances have to be made in order to reduce morbidity and mortality related to silicosis. In this review, we have highlighted the main mechanisms of action that cause lung damage by silica particles and summarized the data concerning the therapeutic promise of cell-based therapy for silicosis.

[The NLRP3 inflammasome: Physiopathology and therapeutic application]

The innate immune system constitutes the first line of host defense against pathogens. "Nonself", such as exogenous particles or pathogens, triggers an inflammatory response. Inflammasomes are molecular platforms activated upon cellular infection or stress that trigger the maturation of proinflammatory cytokines such as IL-1β. Activation of the NLRP3 inflammasome pathway, the most extensively studied, appears to be the corner stone of many inflammatory diseases, including Crohn's disease, rheumatoid arthritis and gout. Cryopyrine-associated periodic syndromes (CAPS) are NLRP3 inflammasome-associated diseases. Canakinumab (Ilaris(®)) is the only drug approved for CAPS treatment in France. Targeted therapy against NLRP3 inflammasome and IL-1β might be the new anti-inflammatory drugs.

Induction of interleukin-1 beta (IL-1β) is a critical component of lung inflammation during influenza A (H1N1) virus infection

Cytokine storm during influenza virus infection is recognized as a predictor of morbidity and mortality. To verify the cellular effects of influenza-induced cytokines in primary normal lung cells, human pulmonary microvascular endothelial cells (HMVECs) and lung fibroblast cells (MRC-5 cells) were infected with influenza virus H1N1. H1N1 infection induced the transcription of various genes encoding cytokines and chemokines such as interleukin-1 beta (IL-1β), IL-6, IL-8, IL-12A, tumor necrosis factor alpha (TNF-α), and chemokine (C-C motif) ligand 5 (CCL5) in both endothelial cells and lung fibroblasts. Among them, IL-1β induction by influenza infection increased the inflammation of lung cells; conversely, blockade of IL-1β signals with an IL-1β receptor antagonist or a neutralizing antibody alleviated influenza-driven inflammation. In conclusion, these data suggest that secreted IL-1β by the endothelial cells contributes to influenza-induced inflammation, and blockade of IL-1β signals is a potential treatment or therapeutic target for influenza-induced inflammation.

Pregnane X receptor modulates the inflammatory response in primary cultures of hepatocytes

Bacterial sepsis is characterized by a rapid increase in the expression of inflammatory mediators to initiate the acute phase response in liver. Inflammatory mediator release is counterbalanced by the coordinated expression of anti-inflammatory molecules such as interleukin 1 receptor antagonist (IL1-Ra) through time. This study determined whether activation of pregnane X receptor (PXR, NR1I2) alters the lipopolysaccharide (LPS)-inducible gene expression program in primary cultures of hepatocytes (PCHs). Preactivation of PXR for 24 hours in PCHs isolated from wild-type mice suppressed the subsequent LPS-inducible expression of the key inflammatory mediators interleukin 1β (IL-1β), interleukin 6 (IL-6), and tumor necrosis factor α (TNFα) but not in PCHs isolated from Pxr-null (PXR-knockout [KO]) mice. Basal expression of key inflammatory cytokines was elevated in PCHs from PXR-KO mice. Stimulation of PCHs from PXR-KO mice with LPS alone produced enhanced levels of IL-1β when compared with wild-type mice. Experiments performed using PCHs from both humanized-PXR transgenic mice as well as human donors indicate that prolonged activation of PXR produces an increased secretion of IL1-Ra from cells through time. Our data reveal a working model that describes a pivotal role for PXR in both inhibiting as well as in resolving the inflammatory response in hepatocytes. Understanding the molecular details of how PXR is converted from a positive regulator of drug-metabolizing enzymes into a transcriptional suppressor of inflammation in liver will provide new pharmacologic strategies for modulating inflammatory-related diseases in the liver and intestine.

IL1RN and KRT13 Expression in Bladder Cancer: Association with Pathologic Characteristics and Smoking Status

Purpose. To validate microarray data on cytokeratin 13 (KRT13) and interleukin-1 receptor antagonist (IL1RN) expression in urothelial carcinoma of the urinary bladder (UCB) and to correlate our findings with pathologic characteristics and tobacco smoking. Methods. UCB tissue samples (n = 109) and control samples (n = 14) were obtained from transurethral resection and radical cystectomy specimens. Immunohistochemical staining of KRT13 and IL1RN was performed and semiquantitative expression scores were assessed. Smoking status was evaluated using a standardized questionnaire. Expression scores were correlated with pathologic characteristics (tumor stage and grade) and with smoking status. Results. Loss of KRT13 and IL1RN expression was observed in UCB tissue samples when compared to controls (P = 0.007, P = 0.008) in which KRT13 and IL1RN expression were high. IL1RN expression was significantly reduced in muscle-invasive tumors (P = 0.003). In tissue samples of current smokers, a significant downregulation of IL1RN was found when compared to never smokers (P = 0.013). Conclusion. Decreased expressions of KRT13 and IL1RN are common features of UCB and are associated with aggressive disease. Tobacco smoking may enhance the loss of IL1RN, indicating an overweight of proinflammatory mediators involved in UCB progression. Further validation of the influence of smoking on IL1RN expression is warranted.

Biology of platelet-rich plasma and its clinical application in cartilage repair

Platelet-rich plasma (PRP) is an autologous concentrated cocktail of growth factors and inflammatory mediators, and has been considered to be potentially effective for cartilage repair. In addition, the fibrinogen in PRP may be activated to form a fibrin matrix to fill cartilage lesions, fulfilling the initial requirements of physiological wound healing. The anabolic, anti-inflammatory and scaffolding effects of PRP based on laboratory investigations, animal studies, and clinical trials are reviewed here. In vitro, PRP is found to stimulate cell proliferation and cartilaginous matrix production by chondrocytes and adult mesenchymal stem cells (MSCs), enhance matrix secretion by synoviocytes, mitigate IL-1β-induced inflammation, and provide a favorable substrate for MSCs. In preclinical studies, PRP has been used either as a gel to fill cartilage defects with variable results, or to slow the progression of arthritis in animal models with positive outcomes. Findings from current clinical trials suggest that PRP may have the potential to fill cartilage defects to enhance cartilage repair, attenuate symptoms of osteoarthritis and improve joint function, with an acceptable safety profile. Although current evidence appears to favor PRP over hyaluronan for the treatment of osteoarthritis, the efficacy of PRP therapy remains unpredictable owing to the highly heterogeneous nature of reported studies and the variable composition of the PRP preparations. Future studies are critical to elucidate the functional activity of individual PRP components in modulating specific pathogenic mechanisms.

Role of interleukin-1/interleukin-1 receptor antagonist family of cytokines in long-term continuous glucose monitoring in vivo

BACKGROUND

Glucose-sensor-induced tissue reactions (e.g., inflammation and wound healing) are known to negatively impact sensor function in vivo. The roles of cytokine networks in controlling these tissue reactions (i.e., sensor biofouling) is not understood. In the present study, we investigated the role of interleukin-1 receptor antagonist (IL-1Ra), a key anti-inflammatory antagonist of the proinflammatory interleukin-1 cytokines [i.e. interleukin-1 (IL-1) alpha and IL-1 beta] in controlling continuous glucose monitoring (CGM).

METHODS

To investigate the role of IL-1Ra in long-term CGM in vivo, we compared CGM in transgenic mice that overexpress IL-1Ra [interleukin-1 receptor antagonist overexpresser (IL-1Ra~OE), B6.Cg-Tg(IL1rn)1Dih/J] or are deficient in IL-1Ra [interleukin-1 receptor antagonist knockout (IL-1Ra~KO), B6.129S-IL1rn(tm1Dih)/J] with mice that have normal levels of IL-1Ra (C57BL/6) over a 28-day time period.

RESULTS

Mean absolute relative difference (MARD) analysis of CGM results among the mice of varying IL-1Ra levels demonstrated that during the first 21 days, IL-1~KO mice had the greatest tissue inflammation and the poorest sensor performance (i.e., higher MARD values) when compared with normal or IL-1Ra~OE mice. By 28 days post-sensor implantation, the inflammatory reactions had subsided and were replaced by varying degrees of fibrosis.

CONCLUSIONS

These data support our hypothesis on the importance of the IL-1 family of agonists and antagonists in controlling tissue reactions and sensor function in vivo. These data also suggest that local delivery of IL-1Ra genes or recombinant proteins (anakinra) or other IL-1 antagonists such as antibodies or soluble IL-1 receptors would suppress sensor-induced tissue reactions and likely enhance glucose sensor function by inhibiting inflammation and wound healing at sensor implantation sites.

An epithelial armamentarium to sense the microbiota

Intestinal epithelial cells were once thought to be inert, non-responsive cells that simply acted as a physical barrier that prevents the contents of the intestinal lumen from accessing the underlying tissue. However, it is now clear that these cells express a full repertoire of Toll- and Nod-like receptors, and that their activation by components of the microbiota is vital for the development of a functional epithelium, maintenance of barrier integrity, and defense against pathogenic organisms. Additionally, mounting evidence suggests that epithelial sensing of bacteria plays a significant role in the management of the numbers and types of microbes present in the gut microbiota via the production of antimicrobial peptides and other microbe-modulatory products. This is a critical process, as it is now becoming apparent that alterations in the composition of the microbiota can predispose an individual to a wide variety of chronic diseases. In this review, we will discuss the bacterial pattern recognition receptors that are known to be expressed by the intestinal epithelium, and how each of them individually contributes to these vital protective functions. Moreover, we will review what is known about the communication between epithelial cells and various classes of underlying leukocytes, and discuss how they interact with the microbiota to form a three-part relationship that maintains homeostasis in the gut.

Chondrogenic potential of stem cells derived from adipose tissue: a powerful pharmacological tool

Chondrogenesis has been widely investigated in vitro using bone marrow-derived mesenchymal stromal cells (BM-MSCs) or primary chondrocytes. However, their use raises some issues partially circumvented by the availability of Adipose tissue-derived MSCs. Herein; we characterized the chondrogenic potential of human Multipotent Adipose-Derived Stem (hMADS) cells, and their potential use as pharmacological tool. hMADS cells are able to synthesize matrix proteins including COMP, Aggrecan and type II Collagen. Furthermore, hMADS cells express BMP receptors in a similar manner to BM-MSC, and BMP6 treatment of differentiated cells prevents expression of the hypertrophic marker type X Collagen. We tested whether IL-1β and nicotine could impact chondrocyte differentiation. As expected, IL-1β induced ADAMTS-4 gene expression and modulated negatively chondrogenesis while these effects were reverted in the presence of the IL-1 receptor antagonist. Nicotine, at concentrations similar to those observed in blood of smokers, exhibited a dose dependent increase of Aggrecan expression, suggesting an unexpected protective effect of the drug under these conditions. Therefore, hMADS cells represent a valuable tool for the analysis of in vitro chondrocyte differentiation and to screen for potentially interesting pharmacological drugs.

A phase II, multicenter, open-label study evaluating dosing and preliminary safety and efficacy of canakinumab in systemic juvenile idiopathic arthritis with active systemic features

OBJECTIVE

To assess dosing, preliminary safety, and efficacy of canakinumab, a fully human anti-interleukin-1β (anti-IL-1β) antibody, in children with systemic juvenile idiopathic arthritis (JIA) and active systemic features.

METHODS

In this phase II, multicenter, open-label, dosage-escalation study, children with systemic JIA who were ≥4 years of age, had fever, and were receiving ≤0.4 mg/kg/day of corticosteroids were administered a single subcutaneous dose of canakinumab, 0.5-9 mg/kg of body weight, and were redosed upon relapse. Response to treatment was assessed according to an adaptation of the American College of Rheumatology (ACR) pediatric criteria for improvement.

RESULTS

A total of 23 children ages 4-19 years with active disease were enrolled. Of these, 1 patient was excluded from analysis, and 3 of the reenrolled patients were included twice in the efficacy analysis. By day 15 of the first treatment cycle, 15 of 25 patients (60%) had achieved an adapted ACR Pediatric 50 response, with 4 of them achieving inactive disease status. Response was sustained over time, with 11 of 13 patients able to maintain their response throughout the study. In 8 of the 11 responders who had been receiving steroids at baseline, the steroid dosage was decreased from a mean of 0.38 mg/kg/day to 0.13 mg/kg/day over the first 5 months, and 4 of them were able to discontinue steroids. At a dose of 4 mg/kg of canakinumab given subcutaneously every 4 weeks, the median percentage of patients predicted to relapse within 4 weeks was estimated to be 6% (95% confidence interval 1-21). Therapy was generally well tolerated and few patients experienced injection-site reactions.

CONCLUSION

Canakinumab has a promising preliminary safety and efficacy profile in this limited cohort. Based on the findings of this trial, further studies in a larger population of children with systemic JIA are warranted.

Matrilin-3 induction of IL-1 receptor antagonist is required for up-regulating collagen II and aggrecan and down-regulating ADAMTS-5 gene expression

Introduction

Deletion or mutation of the gene encoding the cartilage extracellular matrix (ECM) protein matrilin-3 (MATN3) results in the early onset of osteoarthritis (OA), suggesting chondroprotective properties of MATN3. To understand the mechanisms underlying these properties, we determined the effects of MATN3 protein on the expression of several key anabolic and catabolic genes involved in chondrocyte homeostasis, and the dependence of such regulation on the anti-inflammatory cytokine: IL-1 receptor antagonist (IL-1Ra).

Methods

The effects of recombinant human (rh) MATN3 protein were examined in C28/I2 immortalized human chondrocytes, primary human chondrocytes (PHCs), and primary mouse chondrocytes (PMCs). Messenger RNA levels of IL-1Ra, COL2A1, ACAN, MMP-13, and ADAMTS-4 and -5 were determined using real-time RT-PCR. Knocking down IL-1Ra was achieved by siRNA gene silencing. IL-1Ra protein levels were quantified by ELISA and the Bio-Plex Suspension Array System. COL2A1 protein level was quantified using Western blot analysis. Statistic analysis was done using the two-tailed t-test or one-way ANOVA.

Results

rhMATN3 protein induced gene expression of IL-1Ra in C28/I2 cells, PHCs, and PMCs in a dose- and time-dependent manner. Treatment of C28/I2 cells and PHCs with MATN3 protein stimulated gene expression of COL2A1 and ACAN. Conversely, mRNA levels of COL2A1 and ACAN were decreased in MATN3 KO mice. MATN3 protein treatment inhibited IL-1β-induced MMP-13, ADAMTS-4 and ADAMTS-5 in C28/I2 cells and PHCs. Knocking down IL-1Ra abolished the MATN3-mediated stimulation of COL2A1 and ACAN and inhibition of ADAMTS-5, but had no effect on MATN3 inhibition of MMP-13 mRNA.

Conclusion

Our findings point to a novel regulatory role of MATN3 in cartilage homeostasis due to its capacity to induce IL-1Ra, to upregulate gene expression of the major cartilage matrix components, and to downregulate the expression of OA-associated matrix-degrading proteinases in chondrocytes. The chondroprotective properties of endogenous MATN3 depend partly on its induction of IL-1Ra. Our findings raise a possibility to use rhMATN3 protein for anti-inflammatory and chondroprotective therapy.

Injection-site reactions upon Kineret (anakinra) administration: experiences and explanations

Anakinra (Kineret), a recombinant form of human interleukin-1 (IL-1) receptor antagonist, is approved for the treatment of rheumatoid arthritis (RA) in combination with methotrexate. Kineret is self-administered by daily subcutaneous injections in patients with active RA. The mechanism of action of anakinra is to competitively inhibit the local inflammatory effects of IL-1. Kineret is generally safe and well tolerated and the only major treatment-related side effects that appear are skin reactions at the injection site. Due to the relatively short half-life of anakinra, daily injection of the drug is required. This, in combination with the comparably high rates of injection-site reactions (ISRs) associated with the drug, can become a problem for the patient. The present review summarises published data concerning ISRs associated with Kineret and provides some explanations as to their cause. The objective is also to present some clinical experiences of how the ISRs can be managed.

MSK1 regulates the transcription of IL-1ra in response to TLR activation in macrophages

The activity of the pro-inflammatory cytokine IL (interleukin)-1 is closely regulated in vivo via a variety of mechanisms, including both the control of IL-1 production and secretion as well as naturally occurring inhibitors of IL-1 function, such as IL-1ra (IL-1 receptor antagonist). IL-1ra is homologous with IL-1, and is able to bind but not activate the IL-1 receptor. IL-1ra can be produced by a variety of cell types, and its production is stimulated by inflammatory signals. In the present study, we show that in macrophages the TLR (Toll-like receptor)-mediated induction of IL-1ra from both its proximal and distal promoters involves the p38 and ERK1/2 (extracellular-signal-regulated kinase 1/2) MAPK (mitogen-activated protein kinase) cascades. In addition, we show that MSK1 and 2 (mitogen- and stress-activated kinase 1 and 2), kinases activated by either ERK1/2 or p38 in vivo, are required for the induction of both IL-1ra mRNA and protein. MSKs regulate IL-1ra transcription via both IL-10-dependent and -independent mechanisms in cells. Consistent with this, knockout of MSK in mice was found to result in a decrease in IL-1ra production following LPS (lipopolysaccharide) injection. MSKs therefore act as important negative regulators of inflammation following TLR activation.

Intra-articular gene delivery and expression of interleukin-1Ra mediated by self-complementary adeno-associated virus

BACKGROUND

The adeno-associated virus (AAV) has many safety features that favor its use in the treatment of arthritic conditions; however, the conventional, single-stranded vector is inefficient for gene delivery to fibroblastic cells that primarily populate articular tissues. This has been attributed to the inability of these cells to convert the vector to a double-stranded form. To overcome this, we evaluated double-stranded self-complementary (sc) AAV as a vehicle for intra-articular gene delivery.

METHODS

Conventional and scAAV vectors were used to infect lapine articular fibroblasts in culture to determine transduction efficiency, transgene expression levels, and nuclear trafficking. scAAV containing the cDNA for interleukin (IL)-1 receptor antagonist (Ra) was delivered to the joints of naïve rabbits and those with IL-1beta-induced arthritis. From lavage of the joint space, levels of transgenic expression and persistence were measured by enzyme-linked immunosorbent assay. Infiltrating leukocytes were quantified using a hemocytometer.

RESULTS

Transgene expression from scAAV had an earlier onset and was approximately 25-fold greater than conventional AAV despite the presence of similar numbers of viral genomes in the nuclei of infected cells. Fibroblasts transduced with scAAV produced amounts of IL1-Ra comparable to those transduced with adenoviral and lentiviral vectors. IL1-Ra was present in lavage fluid of most animals for 2 weeks in sufficient quantities to inhibit inflammation of the IL-1beta-driven model. Once lost, neither subsequent inflammatory events, nor re-administration of the virus could re-establish transgene expression.

CONCLUSIONS

scAAV-mediated intra-articular gene transfer is robust and similarly efficient in both normal and inflamed joints; the resulting transgenic expression is sufficient to achieve biological relevance in joints of human proportion.

Regulation of catecholamine release and tyrosine hydroxylase in human adrenal chromaffin cells by interleukin-1beta: role of neuropeptide Y and nitric oxide

Adrenal chromaffin cells synthesize and secrete catecholamines and neuropeptides that may regulate hormonal and paracrine signaling in stress and also during inflammation. The aim of our work was to study the role of the cytokine interleukin-1beta (IL-1beta) on catecholamine release and synthesis from primary cell cultures of human adrenal chromaffin cells. The effect of IL-1beta on neuropeptide Y (NPY) release and the intracellular pathways involved in catecholamine release evoked by IL-1beta and NPY were also investigated. We observed that IL-1beta increases the release of NPY, norepinephrine (NE), and epinephrine (EP) from human chromaffin cells. Moreover, the immunoneutralization of released NPY inhibits catecholamine release evoked by IL-1beta. Moreover, IL-1beta regulates catecholamine synthesis as the inhibition of tyrosine hydroxylase decreases IL-1beta-evoked catecholamine release and the cytokine induces tyrosine hydroxylase Ser40 phosphorylation. Moreover, IL-1beta induces catecholamine release by a mitogen-activated protein kinase (MAPK)-dependent mechanism, and by nitric oxide synthase activation. Furthermore, MAPK, protein kinase C (PKC), protein kinase A (PKA), and nitric oxide (NO) production are involved in catecholamine release evoked by NPY. Using human chromaffin cells, our data suggest that IL-1beta, NPY, and nitric oxide (NO) may contribute to a regulatory loop between the immune and the adrenal systems, and this is relevant in pathological conditions such as infection, trauma, stress, or in hypertension.

Is interleukin-1 a good or bad 'guy' in tumor immunobiology and immunotherapy?

The interleukin-1 (IL-1) family consists of two major agonistic proteins, IL-1alpha and IL-1beta, which are pleiotropic and affect mainly inflammation, immunity, and hemopoiesis. The IL-1 receptor antagonist (IL-1Ra) is a physiological inhibitor of pre-formed IL-1. In their secreted form, IL-1alpha and IL-1beta bind to the same receptors and induce the same biological functions. However, the IL-1 molecules differ in their compartmentalization within the producing cell or the microenvironment. Thus, IL-1beta is solely active in its secreted form, whereas IL-1alpha is mainly active in cell-associated forms (intracellular precursor and membrane-bound IL-1) and only rarely as a secreted cytokine, mainly by macrophages/monocytes. IL-1 is abundant at tumor sites, being produced by cellular elements of the tumor microenvironment or by the malignant cells, and it affects not only various phases of the malignant process, such as carcinogenesis, tumor growth, and invasiveness, but also patterns of interactions between malignant cells and the host's immune system. Hence, the effects of the IL-1 molecules on the malignant process are complex and are often of an opposing nature. Comparative studies on the differential roles of malignant cell- or host-derived IL-1alpha and IL-1beta in different stages of the malignant process can subsequently open new avenues for manipulation of IL-1 expression and function in cancer immunotherapy.

Type I IFN induced IL1-Ra expression in hepatocytes is mediated by activating STAT6 through the formation of STAT2: STAT6 heterodimer

The biological activities of type I interferons (IFNs) are mediated by their binding to a heterodimer receptor complex (IFNAR1 and IFNAR2), resulting in the activation of the JAK (JAK1 and TYK2)-STAT (1, 2, 3, 5 isotypes) signalling pathway. Although several studies have indicated that IFN-alpha and IFN-beta can activate complexes containing STAT6, the biological role of this activation is still unknown. We found that exposure of hepatoma cells (HuH7 and Hep3B) to IFN-alpha or IFN-beta led to the activation of STAT6. Activated STAT6 in turn induced the formation of STAT2: STAT6 complexes, which led to the secretion of IL-1Ra. The activation of STAT6 by type I IFN in hepatocytes was mediated by JAK1 and Tyk2. In addition, IFN-alpha or IFN-beta significantly enhanced the stimulatory effect of IL-1beta on production of IL-1Ra. The present study suggests a novel function of IFN-alpha and IFN-beta signalling in human hepatocytes. Our results provide evidence for the mechanism how IFN-alpha and IFN-beta modulate inflammatory responses through activation of STAT6 and production of secreted IL-1Ra.

Levels of adiponectin, C-reactive protein and interleukin-1 receptor antagonist are associated with insulin sensitivity: a population-based study

BACKGROUND

We evaluated the relationship of insulin sensitivity (assessed with the quantitative insulin sensitivity check index, QUICKI) to adiponectin and pro-inflammatory markers, levels of high-sensitivity C-reactive protein (hs-CRP) and interleukin-1 receptor antagonist (IL-1 Ra).

METHODS

Cross-sectional study. Study population (N=923, i.e 411 men and 512 women) included five different population-based age groups (born in 1942, 1947, 1952, 1957 and 1962), [mean age 46 years and mean body mass index (BMI) 26 kg/m(2)]. Study protocol included an interview and measurements of anthropometric parameters and glucose, insulin, adiponectin, hs-CRP and IL-1 Ra.

RESULTS

Correlation (r) between QUICKI and adiponectin level was 0.334 [95% confidence intervals (CI), 0.275-0.392] and partial correlation adjusted for gender, BMI, smoking status, physical activity and age was 0.247 (95% CI, 0.185-0.308). There was negative correlation between QUICKI and IL-1 Ra (r= -0.385; 95% CI, -0.440 to -0.328) which remained statistically significant after the adjustment for confounding factors (r= -0.178; 95% CI, -0.240 to -0.113). Similarly, QUICKI was negatively correlated with hs-CRP (r= -0.241; 95% CI, -0.302 to -0.178), but after the adjustment it lost its statistical significance. There was a statistically significant gender difference (p=0.018) in correlation between QUICKI and IL-1 Ra levels (men: r= -0.348; 95% CI, -0.436 to - 0.261; women r= -0.500; 95% CI, -0.537 to -0.398).

CONCLUSIONS

Our results show that adiponectin level and markers of low-grade inflammation are related to insulin sensitivity. Adiponectin and IL-1 Ra levels might be better markers of the risk of obesity and type 2 diabetes than hs-CRP.

Resistin in serum is associated with higher levels of IL-1Ra in post-menopausal women with rheumatoid arthritis

OBJECTIVES

The aim of this study was to investigate associations between serum levels of resistin, an adipokine and markers of inflammation, bone metabolism, plasma lipids and kidney function in post-menopausal RA patients and to evaluate if HRT during 2 yrs affected resistin levels.

METHODS

Eighty-eight women were randomly allocated to receive HRT, vitamin D(3) and calcium or vitamin D(3) and calcium alone. Serum levels of resistin, IL-1beta, IL-1 receptor antagonist (IL-1Ra), IL-6, IL-6 soluble receptor, TNF-alpha were measured by ELISA, markers of bone metabolism, carboxyterminal cross-linked telopeptide of type I collagen (ICTP) and carboxyterminal propeptide of type I procollagen by RIA, ESR, CRP, Hb, creatinine and lipids by standard laboratory techniques, BMD and total lean mass (TLM) by DXA and joint destruction by Larsen score. Resistin was also measured in 42 healthy control women.

RESULTS

There was no difference in resistin concentration between patients and healthy controls. Resistin was significantly correlated with IL-1Ra, CRP, TNF-alpha, ICTP, glucocorticosteroids and Larsen score and inversely with BMD, hip and with TLM. In multiple regression analysis, IL-1Ra, TLM and use of corticosteroids remained determinants of resistin. Patients treated with HRT displayed significant increase in resistin compared with controls in the first but not the second year.

CONCLUSIONS

Resistin was associated with increased inflammation, particularly by the acute-phase reactant IL-1Ra antagonizing IL-1beta, joint destruction, glucocorticosteroids and with reduced BMD and TLM. These findings suggest resistin being a significant mediator in the inflammatory process in RA. Further studies examining the mechanisms behind the relation between resistin and IL-1Ra are encouraged. HRT does not seem to have important long-term effect on resistin.

Association of C-reactive protein, interleukin-1 receptor antagonist and adiponectin with the metabolic syndrome

This Finnish population-based study, mean age 46 years, evaluates the association of high-sensitivity C-reactive protein (hs-CRP), interleukin-1 receptor antagonist (IL-1Ra), and adiponectin with the NCEP and IDF definitions of metabolic syndrome (MetS). Adiponectin levels were higher, hs-CRP and IL-1Ra levels lower in subjects without MetS compared to subjects with MetS. If MetS was present according to both IDF and NCEP criteria, BMI, waist, triglycerides, hs-CRP, and IL-1Ra were significantly higher compared to subjects who had MetS according to either only IDF or only NCEP criteria. The hs-CRP, IL-1Ra, and adiponectin linearly correlated with the number of the components of MetS according to both definitions. Decreased levels of adiponectin and increased levels of hs-CRP and IL-1Ra are tightly associated with the components of MetS. Individuals who had MetS according to both criteria had the most adverse changes in cardiovascular risk factors.