IL-6 In Humans Research Articles

Immuno(T)herapy for age-related diseases.

During the last decade, the stimulation of T-cell function by the blockage of immunosuppressive checkpoints has experienced an outstanding impact in the treatment of cancer. Development of the chimeric antigen receptor T-cell technology has also emerged as a powerful alternative for patients suffering from oncological processes, especially those affected by hematological neoplasms. Recent evidence suggest that the use of immunotherapy could be extended to non-oncological diseases and could be especially relevant for age-associated disorders, opening exciting therapeutic options for a wide range of diseases of the elderly. Here we comment on the emergence of T-cell-based immunotherapies as feasible approaches that could revolutionize the future of GeroScience.

Tocilizumab induced immunosuppression in a case of adult-onset still’s disease: are these newer biologics double edged sword?

Adult-onset still’s disease (AOSD) is a rare multisystemic inflammatory disorder of unknown etiology characterised by high spiking fever, evanescent skin rash, arthralgias, arthritis, neutrophilic leucocytosis. Initial treatment strategy includes use of hands-on drugs like non-steroidal anti-inflammatory drugs, low dose corticosteroids, conventional DMARDs. But as the disease progresses to severe form, targeted and biologic DMARDs could be the option for management. Interleukin-6 being one among the many cytokines involved in the pathogenesis of AOSD, has made itself a target for the treatment of refractory cases. Tocilizumab, a recombinant humanized anti IL-6 monoclonal antibody, is one such biologic drug available in the market that has proven its therapeutic efficacy in several clinical trials. We are presenting a case of 37-year-old female patient, known case of AOSD for 4 years. Patient was initially maintained on low dose corticosteroid and conventional DMARD like hydroxychloroquine and methotrexate. Flare ups of the disease warranted the use of tocilizumab and tofacitinib in this patient. After clinical as well as pathological improvement with tocilizumab 2 years before, signs of immunosuppression were observed when tocilizumab was reintroduced for the treatment. Patient suffered from acute pyelonephritis, septicemia, shock, oropharyngeal candidiasis and bronchitis which could be owned to immunosuppressive action of tocilizumab. One can reduce the chances of infection and other adverse effects by careful periodic monitoring of various laboratory parameters like total W.B.C., total platelet count and liver enzymes. Cautious selection of the patient is needed for the treatment with newer biologic agents.

Abstract CT189: PRTX007, an optimized TLR7 agonist for systemic immunotherapy of cancers: Interim analysis of phase I study in healthy volunteers

Abstract Background. Toll-like receptor 7 (TLR7) agonists have long been recognized as potential systemic anti-cancer immunotherapy agents. However, clinical development has been limited by complex target-mediated pharmacology including those associated with elevated levels of proinflammatory factors, which also limit the ability to combine with immune checkpoint inhibitors (CPI). PRTX007 is an orally administered prodrug of PRX034, a novel TLR7 agonist that elicits IFN-mediated immune induction without inducing inflammation via the NF-κβ pathway. QOD dosing in primates maintains a stable immune response without immune exhaustion or toxicity. Efficacy, safety, and compatibility with immune CPI were demonstrated in a CT26 syngeneic rodent tumor model. Methods. We conducted a phase 1, single-center, prospective, randomized, double-blind placebo-controlled study of 8 single-ascending dose (SAD) and 4 multiple-ascending dose (MAD) cohorts of PRTX007 administered orally to healthy adult participants. Primary objectives were safety and tolerability. Secondary objectives were evaluation of pharmacokinetics (PK) and pharmacodynamics. This interim analysis focuses on the 8 SAD (50-600 mg) and 2 MAD (300-400 mg) cohorts, with 64 of the 84 participants in the study receiving drug. Results. Treatment-related adverse events include non-dose‒related mild headache, and minor dose-related increases in ALT (<2X ULN) that rapidly resolved. The PKs of PRTX007 and PRX034 are well-behaved eg, exposure increasing proportionally with PRTX007 dose. Consistent with studies in human cells in vitro and non-human primates in vivo, oral administration of PRTX007 elicits systemic TLR7-mediated immune induction without engaging NF-κβ─mediated biosynthesis of IL-6, TNFα and IL-1β in humans. A single dose of PRTX007 (300-600 mg) elicits coordinated expression of IFN-stimulated genes (ISGs) in blood without quantifiable increases in circulating IFNs. At 500 and 600 mg doses, IP-10, IL-1RA, MCP-1 and TRAIL but not IL-6, TNFα or IL-1β increase in plasma (maximal response = 4020, 1460, 650 and 360 pg/ml, respectively). When PRTX007 is administered for 2 weeks on a QOD schedule at 400 mg/dose, the degree of ISG expression progressively increases when compared to the first-dose response, (eg, ISG15 increases 2.1-fold [geometric mean] following Dose 1 vs pretreatment baseline, rising to 12.2-fold following Dose 7). This is accompanied by modest activation of circulating NK, B, and CD4+ and CD8+ T cells as measured by cell-surface markers. IL-6, TNFα and IL-1β remain unchanged from pretreatment levels. Conclusion. At the interim analysis, PRTX007 demonstrated a favorable safety profile when administered orally to all tested SAD and MAD cohorts. Dose-dependent systemic exposure was observed, as well as activation of the innate immune response, without production of proinflammatory factors. Citation Format: Charlotte Lemech, Christopher Argent, Curtis Scribner, Richard Daniels, James Richard Appleman. PRTX007, an optimized TLR7 agonist for systemic immunotherapy of cancers: Interim analysis of phase I study in healthy volunteers [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr CT189.

A systematic review and meta-analyses of interleukin-1 receptor associated kinase 3 (IRAK3) action on inflammation in in vivo models for the study of sepsis.

BackgroundInterleukin-1 receptor associated kinase 3 (IRAK3) is a critical modulator of inflammation and is associated with endotoxin tolerance and sepsis. Although IRAK3 is known as a negative regulator of inflammation, several studies have reported opposing functions, and the temporal actions of IRAK3 on inflammation remain unclear. A systematic review and meta-analyses were performed to investigate IRAK3 expression and its effects on inflammatory markers (TNF-α and IL-6) after one- or two-challenge interventions, which mimic the hyperinflammatory and immunosuppression phases of sepsis, respectively, using human or animal in vivo models.MethodsThis systematic review and meta-analyses has been registered in the Open Science Framework (OSF) (Registration DOI: 10.17605/OSF.IO/V39UR). A systematic search was performed to identify in vivo studies reporting outcome measures of expression of IRAK3 and inflammatory markers. Meta-analyses were performed where sufficient data was available.ResultsThe search identified 7778 studies for screening. After screening titles, abstracts and full texts, a total of 49 studies were included in the systematic review. The review identified significant increase of IRAK3 mRNA and protein expression at different times in humans compared to rodents following one-challenge, whereas the increases of IL-6 and TNF-α protein expression in humans were similar to rodent in vivo models. Meta-analyses confirmed the inhibitory effect of IRAK3 on TNF-α mRNA and protein expression after two challenges.ConclusionsA negative correlation between IRAK3 and TNF-α expression in rodents following two challenges demonstrates the association of IRAK3 in the immunosuppression phase of sepsis. Species differences in underlying biology affect the translatability of immune responses of animal models to human, as shown by the dissimilarity in patterns of IRAK3 mRNA and protein expression between humans and rodents following one challenge that are further influenced by variations in experimental procedures.

Interleukin 6 –174 G/C polymorphism: its relation to coronary artery disease and circulating IL-6 levels – a systematic review and meta-analysis

Abstract Introduction Circulating IL-6 levels and at least one polymorphic form of IL6 gene (IL6 –174 G/C, rs1800795) have been found to be independently associated with coronary artery disease (CAD). However, the association status of this polymorphism with CAD remains unclear. Purpose We conducted a systematic review and updated meta-analysis to comprehensively ascertain the association status of IL6 –174 G/C with CAD and its effect on the levels of circulating IL-6 in humans. Methods Comprehensive online search was undertaken to find relevant case-control/cohort studies investigating the association of IL6 –174 G/C with CAD. The association status of –174 G/C with CAD amongst pooled sample as well as separately amongst different ancestral populations was assessed. Association of –174 G/C with circulating IL-6 levels was also assessed amongst pooled sample as well as separately for CAD cases and CAD-free controls. Study-level odds ratios (OR) and 95% confidence intervals (CI) were pooled by Mantel-Haenszel fixed-effects models. Results Quantitative synthesis for assessing the role of this polymorphic variant in CAD was performed using 55 separate qualifying studies with a collective sample size of 51,213 (19,160 cases / 32,053 controls). The pooled association of –174 G/C with CAD was found to be statistically significant through dominant (OR= 1.15, 95% CI= 1.05–1.25, p=0.002) as well as allelic genetic model comparisons (OR= 1.13, 95% CI= 1.06–1.21, p=0.0003). Asian and Asian-Indian ancestral subgroups showed significant association with CAD in both genetic model comparisons (OR range= 1.29 to 1.53, p value range ≤0.02). Other ancestral subgroups did not show any meaningful association. Circulating IL-6 levels were found to be significantly higher amongst the “C” allele carriers in the pooled sample (Standard mean difference, SMD= 0.31, 95% CI= 0.01–0.22 pg/ml, p=0.009) as well as the CAD-free control subgroup (SMD= 0.10, 95% CI= 0.02–0.17 pg/ml, p=0.009). CAD case subgroup did not show any significant association (p=0.12). Conclusions The present systematic review and meta-analysis confirms an association between IL6 –174 G/C polymorphism residing in the IL6 gene and CAD, especially amongst Asian and Asian-Indian ancestral groups. Upregulation of plasma IL-6 levels in the “C” allele carriers seem to be at least partly responsible for the observed association. Further investigations with large structured case-control studies amongst these ancestral groups are warranted. Funding Acknowledgement Type of funding sources: None.

1040O Phase II trial of ipilimumab, nivolumab and tocilizumab for unresectable metastatic melanoma

Immunotherapy with ipilimumab and nivolumab has response rates of 45-55%, but 50% of patients (pts) suffer grade 3-5 immune-related adverse events. High serum IL-6 is associated with a poor outcome with checkpoint inhibition and with short survival in many cancers. Tocilizumab is a humanized IL-6 receptor blocking antibody approved for several arthritides and cytokine release syndrome. In anecdotal cases it reverses steroid-resistant colitis and other immune toxicities. To assess if tocilizumab could reduce toxicity and/or augment efficacy of checkpoint inhibition, a phase II trial of ipilimumab, nivolumab and tocilizumab was performed.

Specific inhibition of IL-6 receptor attenuates inflammatory bone loss in experimental periodontitis.

Periodontal pathogenesis takes into consideration that disease results from a complex inflammatory immune response. Among the major cytokines related to periodontal damage, interleukin (IL)-6 enhances a cascade of tissue destruction. Tocilizumab (TCZ) is a humanized monoclonal anti-human IL-6 receptor that inhibits IL-6-mediated proinflammatory activity. This study aimed to elucidate whether TCZ inhibits the deleterious effect of ligature-induced periodontitis. Experimental ligature-induced periodontitis was treated with systemic administration of TCZ intraperitoneally in three different concentration dosages (2mg/kg, 4mg/kg, and 8mg/kg. Euthanasia occurred at 7 and 14 days after the initiation of the study. Local changes in the alveolar bone were measured by bone volume, the ratio of bone volume, and trabecular thickness using microcomputed tomography. Attachment loss and inflammatory infiltrate were evaluated by histology. Immune response was analyzed focusing on the Th17 pattern. TCZ inhibited alveolar bone resorption and attachment loss in 7 and 14 days for all dosage groups in comparison to controls (P < 0.05). Besides, TCZ induced lower expression of inflammatory infiltrate (P<0.05) and less production of Th17-related cytokines (P<0.05) and RANKL (P<0.05). The inhibition of IL-6-mediated proinflammatory activity by IL-6R blocking reduced alveolar bone resorption and attachment loss supported by the modulation of the Th17 periodontal response. Considering the inflammatory status, modulatory therapy may be a promising approach to periodontal disease.

From correlation to causality: the case of Subdoligranulum

ABSTRACT Gut microbes are considered as major factors contributing to human health. Nowadays, the vast majority of the data available in the literature are mostly exhibiting negative or positive correlations between specific bacteria and metabolic parameters. From these observations, putative detrimental or beneficial effects are then inferred. Akkermansia muciniphila is one of the unique examples for which the correlations with health benefits have been causally validated in vivo in rodents and humans. In this study, based on available metagenomic data in overweight/obese population and clinical variables that we obtained from two cohorts of individuals (n = 108) we identified several metagenomic species (MGS) strongly associated with A. muciniphila with one standing out: Subdoligranulum. By analyzing both qPCR and shotgun metagenomic data, we discovered that the abundance of Subdoligranulum was correlated positively with microbial richness and HDL-cholesterol levels and negatively correlated with fat mass, adipocyte diameter, insulin resistance, levels of leptin, insulin, CRP, and IL6 in humans. Therefore, to further explore whether these strong correlations could be translated into causation, we investigated the effects of the unique cultivated strain of Subdoligranulum (Subdoligranulum variabile DSM 15176 T) in obese and diabetic mice as a proof-of-concept. Strikingly, there were no significant difference in any of the hallmarks of obesity and diabetes measured (e.g., body weight gain, fat mass gain, glucose tolerance, liver weight, plasma lipids) at the end of the 8 weeks of treatment. Therefore, the absence of effect following the supplementation with S. variabile indicates that increasing the intestinal abundance of this bacterium is not translated into beneficial effects in mice. In conclusion, we demonstrated that despite the fact that numerous strong correlations exist between a given bacteria and health, proof-of-concept experiments are required to be further validated or not in vivo. Hence, an urgent need for causality studies is warranted to move from human observations to preclinical validations.

IL-1β-MyD88-mTOR Axis Promotes Immune-Protective IL-17A+Foxp3+ Cells During Mucosal Infection and Is Dysregulated With Aging

CD4+Foxp3+Tregs maintain immune homeostasis, but distinct mechanisms underlying their functional heterogeneity during infections are driven by specific cytokine milieu. Here we show that MyD88 deletion in Foxp3+ cells altered their function and resulted in increased fungal burden and immunopathology during oral Candida albicans (CA) challenge. Excessive inflammation due to the absence of MyD88 in Tregs coincided with a reduction of the unique population of IL-17A expressing Foxp3+ cells (Treg17) and an increase in dysfunctional IFN-γ+/Foxp3+ cells (TregIFN-γ) in infected mice. Failure of MyD88-/- Tregs to regulate effector CD4+ T cell functions correlated with heightened levels of IFN-γ in CD4+ T cells, as well as increased infiltration of inflammatory monocytes and neutrophils in oral mucosa in vivo. Mechanistically, IL-1β/MyD88 signaling was required for the activation of IRAK-4, Akt, and mTOR, which led to the induction and proliferation of Treg17 cells. In the absence of IL-1 receptor signaling, Treg17 cells were reduced, but IL-6-driven expansion of TregIFN-γ cells was increased. This mechanism was physiologically relevant during Candida infection in aged mice, as they exhibited IL-1 receptor/MyD88 defect in Foxp3+ cells, loss of p-mTORhighTreg17 cells and reduced levels of IL-1β in oral mucosa, which coincided with persistent tongue inflammation. Concurrent with Treg dysfunction, aging was associated with increased CD4+ T cell hyperactivation and heightened levels of IL-6 in mice and humans in oral mucosa in vivo. Taken together, our data identify IL-1β/MyD88/Treg axis as a new component that modulates inflammatory responses in oral mucosa. Also, dysregulation of this axis in an aging immune system may skew host defense towards an immunopathological response in mucosal compartments.

Topical applications of an emollient reduce circulating pro-inflammatory cytokine levels in chronically aged humans: a pilot clinical study.

While increased levels of circulating inflammatory cytokines in chronologically aged humans have been linked to the development of ageing-associated chronic disorders (e.g., cardiovascular disease, type II diabetes, osteoporosis and Alzheimer's disease), approaches that reduce circulating cytokines are not yet available. In chronologically aged mice, we recently demonstrated that epidermal dysfunction largely accounts for age-associated elevations in circulating cytokine levels, and that improving epidermal function reduced circulating cytokine levels. We performed a pilot study to determine whether improving epidermal function reduces circulating pro-inflammatory cytokine levels in aged humans. Thirty-three aged humans were topically treated twice-daily for 30days, with≈3mL of an emollient, previously shown to improve epidermal function, while untreated, aged humans and a cohort of young volunteers served as controls. Changes in epidermal function and levels of three key, age-related, plasma cytokines (IL-1β, IL-6 and TNFα) were measured at baseline and after treatment, using Luminex 200™ system. We also found significantly higher baseline levels of IL-1β, IL-6 and TNFα in aged vs. young humans (P<0.001), as previously reported. Topical applications of the barrier repair emollient significantly enhanced epidermal permeability barrier function (P<0.01) and stratum corneum hydration (P<0.05). In parallel, circulating levels of IL-1β and IL-6 normalized, while TNFα levels declined substantially. The results of this preliminary study suggest that a larger clinical trial should be performed to confirm whether improving epidermal function also can reduce circulating pro-inflammatory cytokine levels in aged humans, while also possibly attenuating the downstream development of chronic inflammatory disorders in the aged humans.

Obesity Promotes Breast Cancer Radioresistance Through Obesity-Altered Adipose Stem Cells in Preclinical Models

Adipose stem cells (ASCs) are mesenchymal stem cells resident in adipose tissue. They are known to be recruited to sites of inflammation to secrete factors that promote wound healing and regeneration. In inflammatory environments ASCs modulate the environment through adipokines, cytokines and growth factors to promote cell growth and regeneration. Obesity results in chronic low-grade inflammation of adipose tissue which alters the biology of resident ASCs. ASCs from obese individuals (obASCs) have been shown to promote proliferation and metastasis of breast cancer in comparison to lean ASCs (lnASCS) in vitro and in vivo. The pro-survival secretome secreted by ASCs led us to investigate the role of lnASCs and obASCs in breast cancer radioresistance. The 5.0 x104 estrogen receptor positive (ER+) breast cancer cell line MCF7 were cocultured for 96 hours in a transwell system with 5.0 x 104 pooled donors (n=3) of lnASCs or obASCs, or were cultured without ASCs. A cesium irradiator was used to irradiate breast cancer cells after 96 hours of co-culture at doses of 0, 2, 5, 10 Gy and further incubated 24 hours. Cell survival after irradiation was determined by colony forming unit assay. Total cellular RNA was extracted from MCF7 cells using RNeasy Mini Kit. One μg of RNA was converted to cDNA with. Quantitative real-time PCR was performed using EXPRESS SYBR GreenER. Breast cancer cells were treated with 40 mg/ml humanized recombinant IL-6 and experiments were repeated. Finally, MCF7 were cocultured with obASCs and Il-6 neutralizing antibody to determine the effects of IL-6 on cell survival and radioresistance promoted by obASCs. The ER+ breast cancer cell line, MCF7, has an increased survival fraction and are better protected from therapeutic doses of ionizing radiation when cocultured with obASCs. IL-6 has been reported to play a protective role in resistance to radiation and thus was a prime candidate for the mediator for the radioresistance conferred by obASCs. We saw a significant increase in IL-6 expression in ER+ breast cancer co-cultured with ASCs. We repeated the experiments treating MCF7 with recombinant humanized IL-6 at physiological doses and saw similar survival enhancing effects, as would be expected from the literature. Finally, we cocultured MCF7 with obASCs and an IL-6 neutralizing antibody and found that neutralizing Il-6 abrogated the effects. Obesity is an important risk factor for breast cancer. Obesity not only increases the incidence of breast cancer, but also the mortality rate. Obesity has been shown to promote metastasis and drug resistance of breast cancer. Here we demonstrate obASCs enhancing survival of ER+ breast cancer after exposure to radiation. This study sheds new light on ASCs promotion of breast cancer, which has important clinical implications on the increased mortality rates of obese women with breast cancer.

Effects of Olive Oil on TNF-α and IL-6 in Humans: Implication in Obesity and Frailty.

Tumor necrosis factor-alpha (TNF)-α and interleukin (IL)-6 are important mediators of chronic low-grade systemic inflammation. The latter plays a central role in several obesity-related pathologies, such as diabetes, metabolic syndrome and cardiovascular diseases. Besides, these cytokines have been also implicated in geriatric and cancer-induced anorexia, cachexia, sarcopenia and frailty. Potential interventions for both obesity and frailty include dietary advice and nutraceuticals. In this context, the consumption of olive oil (OO) has been associated with the health effects of the Mediterranean diet (Med-diet). This review is aimed to discuss the OO-mediated modulation of TNF- α and IL-6 in human studies and the potential implication in obesity and frailty. The reviewed studies suggest that the improvement of postprandial TNF-α and IL-6 observed with OO consumption is affected by body mass index (BMI). The effects on TNF-α and IL-6 after medium and long-term consumptions involved many factors and the cross-talk between adipose tissue, liver, skeletal muscle and brain. Major anti-inflammatory effects were observed when OO was consumed with Med-diet, which is associated with healthy behaviors. In this context, the role of microbioma- polyphenols, diet-gene and exercise-gene interactions in the effects of OO on immune-mediated inflammatory responses involved in obesity and frailty deserves further investigation. Further studies are needed to clarify the effect of OO net of possible synergistic effects with other dietary and lifestyle factors of Mediterranean area.

DİABET HASTALIĞININ SİTOKİNLERLE İLİŞKİSİ

In this study, the relationship of diabetes mellitus with cytokines was revealed. Diabetes is the rising of blood sugar level in the body. The Diabetes occurs when the blood sugar level rises above 120 and generally known as hyperglycemia. Diabetes mellitus has a close relationship with obesity. Obesity is a low gradient inflammatory disease. In obesity, there are studies in which resistin, adiponectin, ghrelin, leptin, C-reactive protein, interleukin-6, TNF-α and fibrinogen-like some biochemical parameters have been correlated with the insulin resistance and cardiovascular risk factors. Cytokine production and the insulin resistance relating the obesity have a relationship that explained as increased secretion by fat adipose tissue. There is an enormous relationship between plasma IL-6 level and insulin sensitivity and there is a clear inverse ratio between them. Generally, CRP is produced as a result of IL-6, IL-1 and TNF-α balance in humans. Some studies indicate the proportional relationship between CRP levels and fat tissues in the body. In a literature study, it’s indicated that IL-6, CRP and fibrinogen levels in type-2 diabetes patients particularly IL-6 and fibrinogen level have been increased. In another study, plasma fibrinogen and d-dimer levels of patients with fasting sugar were higher than type-2 diabetes and normal groups. Also, studies have suggested that there may be an indirect relationship between CRP levels and an increase in the serum concentrations of cytokines such as IL-6 and TNF-α. As a result, cytokines can affect the pathogenesis of patient diabetes.

Safety of tocilizumab in the treatment of juvenile idiopathic arthritis

ABSTRACTIntroduction: Tocilizumab (TCZ) is a recombinant humanized monoclonal antibody and IL-6 receptor antagonist, currently approved for the treatment of systemic juvenile idiopathic arthritis (sJIA) and polyarticular juvenile idiopathic arthritis (pJIA) in children aged 2 years or older refractory to conventional treatment. The most common adverse events in patients treated with TCZ were infections, especially in the respiratory tract. The most frequent laboratory abnormalities were altered liver function, neutropenia and elevated cholesterol levels.Areas covered: The safety of TCZ in the treatment of children with JIA was determined based on a review of published clinical trials, including two multicenter studies of patients with sJIA and pJIA (the TENDER and CHERISH trials, respectively). The frequency of adverse events (AEs), serious adverse events (SAEs) and deaths reported in these studies was analyzed and discussed.Expert opinion: TCZ was effective and well tolerated in the treatment of severe forms of sJIA and pJIA, and can be considered a treatment of choice for these conditions. The risk of infections and laboratory abnormalities, such as neutropenia, should be constantly monitored. There is still a need for comparative studies of the risks and benefits of biological agents in patients with refractory JIA.

In situ analysis of interleukin-6 expression at different sites of zygapophyseal joints from patients with ankylosing spondylitis in comparison to controls

Objectives: Analysis of interleukin (IL)-6 serum levels in patients with ankylosing spondylitis (AS) has indicated that IL-6 might be a pro-inflammatory cytokine involved in AS. However, two placebo-controlled trials with monoclonal antibodies directed against the IL-6 receptor have failed to demonstrate the efficacy of the monoclonal humanized anti-human IL-6 receptor antibody over placebo for the treatment of symptoms of AS. In this study we conducted an in situ analysis of IL-6 expression at different sites of inflammation in zygapophyseal joints of patients with AS in comparison to osteoarthritis autopsy controls (CO).Method: Our immunohistochemical analysis involved 14 patients with AS, 12 autopsy controls (CO), and 11 patients with osteoarthritis (OA). Immunohistochemistry was performed to detect IL-6+ cells at five different sites: within subchondral bone marrow, fibrous tissue replacing subchondral bone marrow, hyaline cartilage, and the subchondral bone plate, and at entheseal sites.Results: Apart from changes in subchondral bone marrow, no significant differences were observed at the sites analysed when comparing AS patients and controls. A significantly lower frequency of IL-6+ cells was evident in AS patients compared to controls (p = 0.0043). In addition, AS patients tended to have even lower percentages of IL-6+ cells than controls at subchondral bone plates and entheseal sites. A significantly lower number of IL-6 expressing cells was also seen within the fibrous tissue of AS compared to OA patients (p = 0.0237).Conclusions: This in situ analysis confirms that IL-6 is not a key player in the pathogenesis of inflammatory processes in spondyloarthritides (SpA). The relevance of pro-inflammatory agents in axial SpA might be studied better in situ in bony specimens at the primary site of inflammation.

FRI0559 Tocilizumab in the Treatment of Refractory Uveitis in Children

BackgroundChildren with refractory uveitis present a unique therapeutic challenge as 50% - 75% of these children will develop significant visual impairment and treatment options are limited. Tocilizumab is a recombinant...

Inhibition of IL-6 signaling by zinc leads to repression of the Th17 response (IRM11P.763)

Abstract Zinc is an essential trace element that plays pivotal roles in multiple facets of the immune system. Besides its catalytic and structural roles, zinc also functions as an intracellular signaling molecule, and changes in zinc levels can cause both direct and indirect modulation of immune responses. Further, cytoplasmic levels of bioavailable zinc in immune cells are largely influenced by many extracellular stimuli. Here we provide evidence that zinc alters the cytokine production profile of human CD4 T cells by functioning as an intracellular signaling molecule during T-cell responses. In vitro zinc treatment of T cells in the presence of activated monocytes inhibited IFN-γ and IL-17 producing cells, but not IL-4 producing cells. Of note, production of IL-17+ CD4 T cells, which is significantly upregulated by LPS-stimulated monocytes, was preferentially repressed by zinc. Increased cytoplasmic zinc in T cells suppressed IL-6 signaling via repression of phosphorylation of Stat3, thus leading to an inhibitory effect on Th17 responses facilitated by monocyte-derived IL-6 in humans. These finding suggest that therapeutic manipulation of zinc bioavailability may be a good means by which to modulate CD4 T-cell responses.

FRI0020 Preclinical development of sarilumab, the first fully human monoclonal antibody (MAB) against IL-6r alpha: utilization and value of double humanized animal model

BackgroundInterleukin-6 (IL-6) is a mediator of inflammation. Preclinical study of human IL biology in mouse models is limited by species-restricted signaling reactivity. Genetically modified mice are used with targeted human...

THU0343 No Upregulation of IL-6 at Different Sites in Facet Joints of Patients with Ankylosing Spondylitis Compared to Controls

BackgroundThe analysis of interleukin-6 serum levels in patients with ankylosing spondylitis (AS) have indicated that IL-6 might be a proinflammatory cytokine in AS patients. However, a placebo-controlled trail using Tocilizumab...

Vitamin D status is not associated with inflammatory cytokine levels during experimental human endotoxaemia

Vitamin D has been shown to modulate innate immune responses in vitro and ex vivo; however, human in-vivo data are lacking. At high latitudes, seasonal vitamin D deficiency is common due to alternating ultraviolet (UV)-B radiation exposure. In the present study, we investigated whether levels of 25 hydroxyvitamin D(3) [25(OH)D(3) ] and its active metabolite 1,25 dihydroxyvitamin D(3) [1,25(OH)(2) D(3) ] are subject to seasonal variation and whether plasma levels of these vitamin D metabolites correlate with the in-vivo cytokine response during experimental human endotoxaemia [administration of lipopolysaccharide (LPS) in healthy volunteers]. Plasma levels of 25(OH)D(3) and 1,25(OH)(2) D(3) were determined in samples obtained just prior to administration of an intravenous bolus of 2 ng/kg LPS (derived from Escherichia coli O:113) in 112 healthy male volunteers. In the same subjects, plasma levels of the inflammatory cytokines tumour necrosis factor (TNF)-α, interleukin (IL)-6 and IL-10 were analysed serially after endotoxin administration. Plasma levels of 1,25(OH)(2) D(3) , but not 25(OH)D(3) , were subject to significant seasonal variation, with lower levels in autumn and winter. 25(OH)D(3) and 1,25(OH)(2) D(3) levels did not correlate with plasma cytokine responses. Furthermore, 25(OH)D(3) deficient subjects (< 50 nmol/l) displayed an identical cytokine response compared with sufficient subjects. In conclusion, plasma levels of vitamin D are not correlated with the LPS-induced TNF, IL-6 and IL-10 cytokine response in humans in vivo. These findings question the direct role of vitamin D in modulation of the innate immune response.