Background: Neurological involvement in rheumatoid arthritis (RA) is understudied despite a high prevalence of depression, cognitive deficits, chronic pain, and fatigue reported in RA patients. Furthermore, there is increasing interest in the role of peripheral and brain-resident innate immune cells in aging and neurodegenerative disease. Systemic immune activation has been shown to activate microglia and affect brain region size in models of RA [1,2], but how chronic inflammation affects the aging human brain has not been previously studied. Objectives: We investigate regional brain volumes in RA patients compared to healthy age- and sex-matched controls and relate differences to neuropsychiatric symptoms and peripheral blood CD14+ monocyte phenotypes. Methods: We included 71 female patients (median age 64 years, range 23-76) with established RA (disease duration 10 years, range 0-45) and 268 healthy women (median age of 54 years (21-82)) who served as controls (C). T1-weighted cranial magnetic resonance images were used to measure 120 brain regions. For analysis of brain region differences in relation to age, RA patients and controls were binned into age intervals of 5 years: 0-45y (RA: n=7, C: n=98), 45-50y (RA: n=4, C: n=15), 50-55y (RA: n=11, C: n=26), 55-60y (RA: n=7, C: n=32), 60-65y (RA: n=13, C: n=41), 65-70y (RA: n=21, C: n=25), older than 70y (RA: n=8, C: n=31). Patient-reported neuropsychiatric symptoms were assessed with the Fibromyalgia Impact Questionnaire (FIQ). Peripheral blood CD14+ monocytes were isolated and analysed with RNA sequencing. Genes and pathways associated with lateral ventricle size was identified by comparing patients with lateral ventricle size smaller and larger than 30 cm3. Results: RA patients over 65 had significantly enlarged lateral ventricles of the brain compared to healthy controls of the same age range (Figure 1). While there were no differences in lateral ventricle size between RA patients and controls in participants under 65 years, the lateral ventricles were enlarged by 25% (p=0.020) in patients 65-70, and 42% (p=0.00020) in patients over 70. Next, we analysed regional brain volumes in the 71 RA patients compared to 71 age-matched controls. We found that 7 limbic and 5 cortical regions were significantly different in both the left and right hemisphere. Of these regions, the thalamus, the middle frontal gyrus and the superior frontal gyrus had strong inverse correlations to the lateral ventricle volume (thalamus: Spearman r=-0.46, p=0.0002; middle frontal gyrus: r=-0.56, p<0.0001; superior frontal gyrus: r=-0.36, p=0.0052). Interestingly, the reduced thalamus size was associated with depression reported in the FIQ questionnaire according to a linear model controlling for the patients age (Beta=-21, p=0.0080). Monocytes share characteristics with microglia and can migrate to the brain. We found that CD14+ monocytes from patients with larger lateral ventricles had several activated pathways related to neuroinflammation, including neuroinflammation signalling and multiple-sclerosis signalling. Upregulated genes included CYBB, MSR1, VEGFA, HLA-DRA, A2M and CD9, which implies neurodegenerative microglia phenotypes [3]. Conclusion: RA patients over the age of 65 had larger lateral cerebral ventricles, indicating brain atrophy possibly caused by accelerated aging or neurodegeneration. Enlarged ventricles were likely a consequence of shrinkage of the thalamus as well as frontal cortical regions and were associated with neuropsychiatric symptoms in RA patients. Monocytes of patients with enlarged lateral ventricles had a phenotype associated with neuroinflammation and disease-associated microglia. A limitation to our study is an insufficient sample size for rigorous statistical testing using a split-sample approach. We therefore present our generated hypotheses along with statistical test results as suggestions for future rigorous testing on independent data. REFERENCES: [1] Anderson & Wasén et al., PNAS 2019 [2] Süß et al., Cell Reports 2020 [3] Butovsky & Weiner, Nature Reviews Neuroscience 2018 Acknowledgements: NIL. Disclosure of Interests: None declared.

Background: Rheumatoid arthritis (RA) is an inflammatory joint disease that leads to significant impairment in hand function. Chronic systemic inflammation in RA has been shown to change the activity of specific brain structures [1]. The relationship between brain structure and hand dysfunction in RA is underexplored. Objectives: We investigated structural changes in the brain of RA patients in relation to grip strength (GS), aiming to identify peripheral and brain immune responses associated with these changes. Methods: Based on GS measurement using a dynamometer, we analysed 60 RA patients with an mean age 60 years (range 23-73), disease duration 14 years (range 0-45), and mean GS 197 N (range 29-400). Patients were dichotomized by the median GS to compare the groups with weak GS versus strong GS. A subset of 12 patients underwent hand training consisting of 5 simple exercises performed separately for each hand for 10 minutes daily during 6 months. Instructions were given on an individual basis. Each patient wrote a training diary. Patients reported their functional disability using the Disabilities of the Arm, Shoulder, and Hand (DASH) questionnaire, the Health Assessment Questionnaire (HAQ) and the Fibromyalgia Impact Questionnaire (FIQ). Brain tissue was assessed by T1-weighted magnetic resonance imaging (MRI) at the baseline and after 6 months of hand training for the subset of 12 patients. Volumes of 121 brain regions were analysed using MAPER software with respect to grey matter (GM), white matter (WM), and cerebrospinal fluid (CSF) compartments. Levels of IFNγ in serum and supernatants of CD4+ T cells were determined by ELISA. RNA sequencing was used to analyse the transcriptional profile of peripheral blood CD4+ T cells. Results: RA patients with weak GS had significantly higher functional disability according to DASH and HAQ, and experienced more pain according to FIQ scores (all, p<0.001). There was no significant difference in age, disease duration or disease activity by DAS28 between the weak GS and strong GS patients. We found that the weak-GS patients had significantly increased WM volume in the putamen (L, p=0.002; R, p=0.0046) and caudate nucleus (L, p=0.0082; R, p=0.067) and decreased GM volume in the thalamus (L, p=0.038; R, p=0.028), regions which play a role in planning the execution of movement. Weak-GS patients also had significantly smaller WM volumes of the sensorimotor network, including the precentral gyrus (PG) (L, p=0.025; R, p=0.083), middle frontal gyrus (MFG) (L, p=0.0023; R, p=0.0099) and superior temporal gyrus anterior part (STGAP) (R, p=0.0051). Interestingly, after 6 months of hand training, some of the sensorimotor regions were increased in 12 patients who completed the training (MFG: 0.75% increase, p=0.0024; STGAP: 2.7% increase, p=0.033). Furthermore, weak-GS patients had lower levels of IFNγ in both serum (p=0.0006) and CD4+ T cell supernatants (p=0.0018). In the CD4+ T cells of the weak-GS patients, the downregulated genes were involved in T-cell activation and migration, and IFNγ production and response, while the upregulated genes were related to ribosome biogenesis. Further correlation analysis showed that the IFNγ sensitive genes were significantly correlated with the WM volume of the PG and putamen, and genes involved in ribosome biogenesis were correlated with WM volume of the PG and MFG. Conclusion: Hand GS loss in RA patients is associated with measurable changes in the brain volume of motor cortex and the dorsal striatum. These changes can be mitigated by daily hand training. Regional brain changes were associated with dysregulated immune system and impaired IFNγ production and signalling in CD4+ T cells. This study provides new clues for understanding the interaction between the immune and nervous systems in RA, which should be taken into account during treatment of RA patients. REFERENCES: [1] Schrepf et al. Nature Communications. 2018. Acknowledgements: NIL. Disclosure of Interests: None declared.

IFNG , TBX21 , Eomes , IL2RA , IL2RB , IL12RB2 , TNF , IL18RAP (all, adj. p < 0.05). Conclusion: This study shows that accumulation of Rho-proteins in CD4 + cells results in pro-inflammatory IFN-γ dependent phenotype in mice and human RA. Accumulation of RhoA, Rac1 and Cdc42 proteins trigger the migration of CD4 + cells into joint draining LN and facilitates arthritis. Inhibiting M ø /T cell contact in GLC mice did not suffice to prevent migration of Rho-protein expressing cells

Background: The insulin-like growth factor 1 receptor (IGF1R) signalling mediates numerous developmental processes acting through downstream adaptor molecules IRS1/2, which activate Akt and inhibit the family of forkhead box class O (FoxO). Inhibition of IGF1R signalling alleviates rheumatoid arthritis (RA) (Erlandsson et al., 2017), however, the role of IGF1R signalling in the regulation of immune function is poorly understood. Objectives: To investigate the link between IGF1R signalling and antigen presentation in experimental arthritis. Methods: Arthritis was induced by immunising Balb/c mice with methylated bovine serum albumin (mBSA, n=18) and DBA/1 mice with type II collagen (CII, n=18). The mice were treated with a synthetic IGF1R inhibitor NT157 or with short hairpin RNA targeting IGF1R (shIGF1R) from the day prior to immunisation. Controls were treated with cyclodextrine vehicle/ non-targeting (nt)RNA, respectively. Flow cytometry was used for spleen cell phenotype. Antibody levels were measured by ELISA. Immunohistochemistry (IHC) of spleen was performed for assessment of marginal zone (MZ) and location of pS 612 IRS1+ and pS 256 FoxO1+ cells. IHC images were acquired by fluorescent confocal microscopy, and analysed using ZEN2009 and Cell Profiler soft ware. Results: The inhibition of IGF1R resulted in an 80% increase in MZ area in NT157-treated mice compared to controls (p=0.0001). This was supported by a significant increase of CD21+ (p=0.034) and CD23+ cell populations (p=0.00059), both among the CD19+ B cells and antigen-presenting MHCII+CD19- cells, implying that IGF1R expression regulates the populations of MZ and follicular cells. Additionally, there was a strong positive correlation between the decrease of IGF1R+ and ICOSL+ population on CD21+ cells (r=0.70, p=0.0071), which retained them in the MZ and prolonged communication with macrophages. Insufficient feedback from ICOSL- B cells limited expression of CXCR5 on CD4 cells. The IHC analysis displayed that, IGF1R inhibition led to abundance of inactivate pS 612 IRS1+ and pS 256 FoxO1+ cells within the MZ, compared with controls (p=0.0002). Alongside the increase of IgM+ B cell population (p=0.0022), we observed significant increase in number of antigen-presenting F4/80+ cells (p=0.043) and MARCO expression (p=0.043) after IGF1R intervention. Finally, the NT157- treated mice displayed a significant pleiotropic increase in IgM autoantibody production, with anti-CCP IgM (p=0.027), RF-IgM (p=0.0085), anti-DNA IgM (p=0.066) and in total IgM (p=0.027) levels, which correlated positively with pS 256 FoxO1 + cells (r=0.51, p=0.03). Levels of IgG were not changed. Conclusion: We show that IGF1R signalling is important for immune cell communication after antigen challenge. IGF1R controls ICOSL dependent trafficking of B cells through the MZ and facilitates interaction with T cells. Retention of B cells in the MZ tips the balance from T cell to macrophage-dependent processes, which permits the formation of autoantibody producing B cells. References: [1]Erlandsson, M., et.al., 2017. IGF-1R signalling contributes to IL-6 production and T cell dependent inflammation in rheumatoid arthritis. Biochimica et Biophysica Acta (BBA) - Molecular Basis of Disease , 1863(9), pp.2158-2170. Disclosure of Interests: None declared

Mannose is a glucose-associated serum metabolite mainly released by the liver. Recent studies have shown several unexpected pleiotropic effects of mannose including increased regulatory T cells (Tregs). prevention of auto-immune disease and ability to reduce growth of human cancer cells. We have previously shown in large cohorts that elevated serum mannose levels are associated with future development of type 2 diabetes (T2D) and cardiovascular disease. However, potential direct effects of mannose on insulin sensitivity in vivo or in vitro are unknown. We here show that administration of mannose (0.1 g/kg BW twice daily) for one week in man did not elicit negative effects on meal-modified glucose tolerance, markers of inflammation or insulin levels. Tregs number and insulin signaling in human liver cells were unchanged. These data suggest that mannose is a marker, and not a mediator, of insulin resistance. To verify this, we examined serum mannose levels during long-term euglycemic hyperinsulinemic clamps in non-diabetic and T2D individuals. Mannose was reduced by insulin infusion in proportion to whole-body insulin sensitivity. Thus, mannose is a biomarker of insulin resistance which may be useful for the early identification of diabetic individuals with insulin resistance and increased risk of its complications. (C) 2019 Elsevier Inc. All rights reserved.

Background: Depression and cognitive impairment have been frequently reported in rheumatoid arthritis (RA) (1). Studies of the molecular mechanisms behind these phenomena attract increasing attention. We previously reported that signaling through the insulin-like receptor is impaired in RA and has consequences for pain processing (2). Objectives: We investigated the central and peripheral footprint of the major neurotrophin in the central nervous system, brain-derived neurotrophic factor (BDNF), on pain and mood perception of RA patients. Methods: Pain symptomatology was assessed in 216 female RA patients (mean age 52y, mean disease duration 10 years) by a visual analogue scale (VAS), 18 tender points count (TPC), and by pressure-induced pain threshold measurement. The mood was patient-reported based on the Hospital Anxiety and Depression Scale (HADS). Clinical RA activity was assessed by DAS28. Serum levels of BDNF, IL6, IL1b, IL10 and IFN-gamma were measured by ELISA. Transcription of FOXO1 and FOXO3 was measured by RT-PCR in whole-blood RNA. Effect of BDNF signaling in leukocytes was assessed by differentially expressed gene (DEG) analysis in RNAseq of 24 female RA patients (R-studio, Bioconductor). High-resolution brain MRI was performed in a representative selection of 16 patients. Brain volumes were analyzed with MAPER software for accurate measurement of 83 anatomical regions (3) and compared between two groups of patients with high and low serum BDNF, respectively. Results: In RA patients, high serum levels of BDNF were associated with low TPC (4.1 vs 5.3, p=0.04) and higher pain threshold (kPa, 416 vs 382, p=0.09). No connection between BDNF and mood measures was evident. High BDNF was associated with high serum VEGF (p<0,001), IFNg (p=0.0004), IL1b (p=0.036) and serum insulin (p<0,001), but low resistin (p=0.059). No correlation was found between BDNF with either serum IGF1 or inflammation parameters DAS28 and IL6. Serum BDNF was functional, since the RA patients with high BDNF had significantly larger brain volumes in specific regions and significantly lower FOXO1 mRNA in blood leukocytes (p=0.03). Specifically, structures of the limbic system, parahippocampus, lingual gyrus, nucleus accumbens and thalamus, key regions for the transmission of nociceptive information and central modulation of pain, were enlarged. BDNF production was measured in CD4-CD8- PBMC and was inversely related to expression of its high-affinity receptor TrkB in CD4+ PBMC. DEG analysis in CD4 T cells showed that low TrkB was associated with CD28+ transitional memory phenotype. Conclusion: We conclude that high serum BDNF was associated with larger volumes of nociception-related brain regions and lower pain perception, acting independently of IGF1 and systemic inflammation. References: [1] Dougados M, Curr OppRheumatol 2016 [2] Andersson, Wasen, PNAS2017 [3] Heckemann, NeuroImage 2010 Disclosure of Interests: None declared

Introduction In addition to inflammation of the joints, rheumatoid arthritis (RA) has a neurological part consisting of pain, fatigue, depression and cognitive deterioration. These symptoms are critical for the patients’ ability to cope with daily life, but are not alleviated completely with modern antirheumatic drugs. Sufficient IGF1R signalling is important for neurogenesis in the hippocampus. Its misbalance correlates with depression and anxiety. Objectives The aim of this study was to evaluate the pathological changes in the brain during experimental RA and investigate their connexion to IGF1R. Methods Characteristics of pain, depression and anxiety were collected among 214 RA patients and analysed in relation to IGF1R expression in WBC. Experimental RA was induced by immunisation with collagen II. Inhibition of IGF1R was achieved by injection of shRNA-producing lentiviral construct. The behavioural pattern of each mouse was recorded by filming. The hippocampus was analysed morphometrically, and gene and protein expression were analysed by qPCR and immunohistochemistry, respectively. Results The RA patients’ perception of depression and anxiety was associated with high IGF1R expression in WBC. This group of patients was also less physically active. In experimental RA, an enrichment of IBA1 +microglia and high expression of CD68 and IL-1b was found in the hippocampus. This was followed by an increased density of IGF1R+cells in cornu ammoni, and a decreased neurogenesis by limited expression DCX in the subgranular layer of the dentate gyrus. This results in a significant reduction of the hippocampus area. These changes in the brain were associated with immobility in RA mice. Treatment with shRNA targeting IGF1R improved arthritis, but led to increased immobility. Conclusions RA induces remote inflammation in the hippocampus reducing neurogenesis and physical activity. The neurological symptoms in patients and in experimental RA are connected to IGF1R expression and signalling, and further expands our knowledge of neurological processes in RA. Disclosure of interest None declared

Epidermal growth factor receptor (EGFr)-targeted therapy may be used in subgroups of patients with urinary bladder cancer. Here we assessed the role of EGFr in urothelial proliferation and migration in a two- and three-dimensional cell culture system.UROtsa cells derived from normal urothelium and malignant T24 cells were cultured in a Type I collagen gel. Proliferation and migration of urothelial cells, in the absence and presence of the EGFr inhibitor cetuximab, were assessed with a proliferation test (ATCC) and with the Axioplan 2 imaging microscope with a motorized stage (Carl Zeiss), respectively. The expressions of cytokeratin (CK) 17, CK20, EGFr, pEGFr, laminin, occludin and zonula occludens 1 (ZO-1) were assessed with immunohistochemistry and/or western blot.UROtsa spheroids were formed after 7 days in culture, while T24 cells did not form spheroids. UROtsa expressed CK20 but not laminin or CK17 and consequently resembled umbrella cells. In UROtsa and T24, cetuximab inhibited urothelial proliferation, induced cleavage of EGFr and/or pEGFR but did not affect urothelial migration. The tight junction protein occludin was cleaved, and the formation of cellular spheroids was inhibited in UROtsa by the presence of cetuximab.EGFr modulates urothelial proliferation and the formation of the three-dimensional structure of the urothelium possibly by interfering with occludin. The present data also show a cell culture technique enabling phenotypically normal urothelial cells to form epithelial structures in contrast to malignant urothelial cells.

Introduction Ligand to the inducible T cell costimulator (ICOSL) on B cells is essential for the ICOS-dependent follicular recruitment of activated T cells. In patients with Rheumatoid arthritis (RA) the IGF1-IGF1R axis is altered. Inhibition of IGF1R alleviated arthritis by reducing IL-6-dependent formation of Th17 cells. Here we study the role of IGF1R on CD21 +cells in experimental arthritis. Methods Female Balb/c mice were immunised with methylated BSA or with CII. Consequences of the IGF-1R inhibition for arthritis were studied in mBSA and CII-immunised mice treated with NT157 compound promoting degradation of insulin receptor substrates (mBSA) or using shRNA producing construct (mBSA +CII). At termination three sub-populations of CD21 +cells were analysed: follicular dendritic cells (FDc, CD21 +CD19-CXCR5-); marginal zone B cells (MZBc, CD21 +CD19+CXCR5-); follicular B cells (FBc, CD21 +CD19+CXCR5+). Supernatants of LPS-stimulated splenocytes and serum were analysed for production of antigen specific and autoantibodies. Results In spleen of mBSA-immunised mice, ICOSL expression on CD21 +cells correlated to IGF1R (r=0.70). Inhibition of IGF1R induced a 20% reduction in ICOSL expression in all CD21 +subsets followed by an increase in MZBc (p=0.003), while FDc and FBc were unchanged. ICOSL +MZBc were mostly IgMhi, while ICOSL +FBc were mostly IgDhi. Inhibition of IGF1R had no effect on the expression of ICOS +on CD4 T cells and the subset of CXCR5 +follicular T cells. Reduction of the ICOSL +CD21+B cells, reduced production of mBSA-specific IgM and increased production of autoreactive RF-IgM levels. Conclusions The study shows that IGF1R controls expression of ICOSL on CD21 +cells. ICOSL on MZBc is required to balance between antigen-specific response and autoantibody production. Disclosure of interest None declared

Survivin is a protein functionally important for cell division, apoptosis, and possibly, for micro-RNA biogenesis. It is an established marker of malignant cell transformation. In non-malignant conditions, the unique properties of survivin make it indispensable for homeostasis of the immune system. Indeed, it is required for the innate and adaptive immune responses, controlling differentiation and maintenance of CD4+ and CD8+ memory T-cells, and in B cell maturation. Recently, survivin has emerged as an important player in the pathogenesis of autoimmune diseases. Under the conditions of unreserved inflammation, survivin enhances antigen presentation, maintains persistence of autoreactive cells, and supports production of autoantibodies. In this context, survivin takes its place as a diagnostic and prognostic marker in rheumatoid arthritis, psoriasis, systemic sclerosis and pulmonary arterial hypertension, neuropathology and multiple sclerosis, inflammatory bowel diseases and oral lichen planus. In this review, we summarise the knowledge about non-malignant properties of survivin and focus on its engagement in cellular and molecular pathology of autoimmune diseases. The review highlights utility of survivin measures for clinical applications. It provides rational for the survivin inhibiting strategies and presents results of recent reports on survivin inhibition in modern therapies of cancers and autoimmune diseases.

Background:Smoking is a risk factor for developing rheumatoid arthritis (RA), but the mechanism remains uncertain. We previously demonstrated that smoking lowers the T cell activation threshold by limiting programmed death protein 1 (PD-1) expression.Aim:To investigate how smoking influence the levels of soluble PD-1 ligand (sPD-L1).Method:Serum levels of sPD-L1 were measured in 246 RA patients and in 168 healthy subjects. The analysis was done with respect to inflammation, smoking, treatments, and autoantibody status. The effect of therapeutic TNF-inhibiting antibodies (TNFi) on sPD-L1 was studied in 16 RA patients at their first infliximab infusion. The expression of Fcγ-receptor (FcγR) subclass IIB and IIIA was analyzed with quantitative polymerase chain reaction in peripheral blood mononuclear cells (PBMCs) from 12 RA patients and 15 healthy controls, and in healthy PBMC exposed to IgG containing antibodies to cyclic citrullinated peptides (aCCP).Results:The negative association between smoking and sPD-L1 in RA patients was established by multiple logistic regression (OR = 0.52, p = 0.038). Other covariates in the regression model were serum levels of IL-1β representing inflammation (OR = 1.6, p = 0.0076) and aCCP positivity (OR = 1.9, p = 0.047). First infliximab infusion repressed sPD-L1 (p = 0.023) in patients, and low levels of sPD-L1 were found in patients with early RA treated with TNFi (p = 0.018). Treatment with TNFi was associated with higher sPD-L1 in patients with long disease duration (p = 0.041) and restored levels in smokers. In vitro exposure to aCCP+ IgG suppressed sPD-L1 (p = 0.036), but aCCP+ patients with long disease duration had higher sPD-L1 (p = 0.016). High ratio of the inhibitory FcγR subclass IIB over the stimulatory IIIA resulted in low sPD-L1 release (p = 0.029). Smoking was associated with a higher FcγR IIB/IIIA ratio (p = 0.00062) and lower levels of sPD-L1 (p = 0.013).Conclusion:In RA, serum sPD-L1 was related to systemic inflammation and aCCP positivity. Smoking altered the expression of FcγRs and limited sPD-L1 in RA patients, permitting inappropriate T cell responses. Differential regulation of sPD-L1 during the early and late RA may indicate transposition from acute to chronic inflammation.

Background Rheumatoid arthritis (RA) has recently been linked to an exhausted state of CD4+ T cells in peripheral blood of patients [1]. Exhaustion of CD4+ T cells limits their proliferation and increases cell death. In CD8+ T cells smoking counteract exhaustion, which may lead to increased cytotoxic activity exemplified by targeting of cells with high expression of the anti-apoptotic protein survivin [2]. Exhaustion of CD4+ T cells coincides with expression of interferon (IFN) response genes [3], referred to as the IFN signature. The development of the IFN signature has been suggested to predate RA [4]. Objectives We investigated how smoking affect the CD4+ T cell population in peripheral blood of RA patients with focus on the exhaustion marker programmed cell death-1 (PD-1). Methods Blood samples were collected from RA patients and healthy women with different smoking status and analysed for PD-1 and survivin expression using flow cytometry and qPCR. Sorted Th17 cells from peripheral blood were analysed for expression of 18 genes up regulated during exhaustion [3], herein referred to as the exhaustion set, and serum levels of survivin were assessed by ELISA. Peripheral blood CD4+ cells were analysed for their expression of seven IFN response genes [4]. The role of survivin in the formation of exhausted CD4+ T cells was studied in collagen-induced arthritis (CIA), where mice were treated with nicotine or vaccinated with survivin peptides. Results High frequency of exhausted PD-1+CD4+ cells was found in smoking RA patients. The numbers of PD1+CD4+ cells correlated inversely with the PD-1 expression by cytotoxic CD8+CD107+ cells (r=-0.62, p=0.01). Additionally, the frequency of PD-1+CD4+ cells increased with reduction of the CD4+ population (r=-0.71, p=0.002). The IFN signature was found exclusively among smoking RA patients. The patients with the IFN signature all had CD4+ cells with low survivin production. Th17 cells from RA patients with high serum survivin were enriched in genes of the exhaustion set. CD4+ cells with high survivin expression were negative for PD-1, while PD-1hi cells had low expression of survivin. In CIA mice the survivinhiPD-1- CD4+ cells were reduced by nicotine treatment (p=0.03) or survivin vaccination (p=0.009). Conclusions Smoking associates with exhaustion of CD4+ T cells in RA by increasing the frequency of PD-1+CD4+ cells and supporting the IFN signature. Balancing T cell exhaustion and preventing the IFN signature are potential future treatment strategies for RA. References Frenz T, et al. J Allergy Clin Immunol 2016. 138(2): 586–589. Wasén C, et al. J Autoimmun 2017. DOI: 10.1016/j.jaut.2016.12.00. Crawford A, et al. Immunity 2014. 40(2): 289–302. Lübbers J, et al. Ann Rheum Dis 2013. 72(5): 776–780. Disclosure of Interest None declared

The pathophysiology behind radiation cystitis is poorly understood. Here we investigated whether bladder irradiation affects the immune system of the rat urinary bladder. Female rats were sedated and exposed to one single radiation dose of 20 Gy or only sedated (controls) and killed 16 h to 14 days later. Rats were placed in a metabolic cage at 16 h, 3 days, 7 days and 14 days following bladder irradiation. The urinary bladders were harvested and analysed with qPCR, immunohistochemistry and/or Western blot for the expression of interferon (IFN)-γ, interleukin (IL)-1β, IL-2, IL-4, IL-5, IL-6, IL-10, IL-13, nitric oxide synthases (eNOS, iNOS and nNOS), tumour necrosis factor (TNF)-α and toll-like receptor 4 (TLR4). Urine was collected and analysed for IL-6 and nitrite (reflecting nitric oxide activity) with ELISA and the Griess reaction, respectively. Irradiation increased bladder frequency and decreased voiding volumes 14 days following bladder irradiation. Bladder irradiation increased the expression of IL-10 and collagen in the bladder, while TLR4 and IL-6 expressions were decreased in the urothelium concomitantly with a decrease in mast cells in the submucosa and urine levels of IL-6 and nitrite. The present findings show that bladder irradiation leads to urodynamic changes in the bladder and may suppress important immunoregulatory pathways in the urinary bladder.

We wanted to assess whether β-adrenoceptors mediate proliferation in the normal and malignant urothelial cell lines UROtsa and T24, respectively. Urothelial cells were cultured for 24 h in the presence of the β-adrenoceptor agonists isoprenaline (β1/2/3 ), dobutamine (β1 ), salbutamol (β2 ), BRL 37344 (β3 ), CGP 12177 (a partial β-agonist) or β-adrenoceptor antagonists (metoprolol; β1 , propranolol; β1/2 ). Phosphorylation of kinases was screened with a Human Phospho-Kinase Array Kit (R&D systems). Intracellular pathways activated by proliferation of urothelial cells were characterized by incubating cells with the MEK1/2 inhibitor PD 98,059, the p38 kinase inhibitor losmapimod or with the Akt 1/2 kinase inhibitor. Proliferation was assessed with the MTT proliferation assay (ATCC). Western blot and immunocytochemistry were used for detection of the β1 -adrenoceptor. Isoprenaline and dobutamine induced proliferation, while salbutamol and BRL 37344 did not. Dobutamine-induced proliferation was not affected by metoprolol or propranolol but was instead antagonized by CGP 12177 in T24 but not in UROtsa. In response to stimulation with dobutamine, Akt1/2/3 was phosphorylated in UROtsa, while ERK1/2 and p38 were phosphorylated in T24. MEK1/2 inhibition blocked basal and dobutamine-induced proliferation in T24 but only basal proliferation in UROtsa. Losmapimod slightly inhibited basal proliferation in T24 but not dobutamine-induced proliferation. Akt 1/2 inhibitor blocked basal and dobutamine-induced proliferation in UROtsa. Immunocytochemistry and Western blot revealed expression of β1 -adrenoceptors in both urothelial cell lines. The present data show that the urothelium expresses atypical β1-adrenoceptors that activate intracellular kinases inducing urothelial proliferation.