Effectiveness and safety of 12-month certolizumab pegol treatment for axial spondyloarthritis in real-world clinical practice in Europe.

OBJECTIVES: The efficacy and safety of certolizumab pegol (CZP), an Fc-free, PEGylated anti-TNF, in axial spondyloarthritis (axSpA) has been established in clinical trial settings. We report CZP effectiveness and safety in European clinical practice in patients with axSpA, including radiographic (r-) and non-radiographic (nr-) axSpA. METHODS: CIMAX (NCT02354105), a European non-interventional multicentre prospective study, observed CZP treatment response and safety over 12 months in a real-world axSpA cohort. The primary outcome was change from baseline in BASDAI to week 52, with additional outcomes pertaining to effectiveness and safety. Patients who received ≥1 dose CZP were followed up for adverse events, and those with baseline and ≥1 post-baseline BASDAI assessment were included in effectiveness analyses. RESULTS: A total of 672 patients (r-axSpA: 469; nr-axSpA: 201; unconfirmed diagnosis: 2) from 101 sites received ≥1 dose of CZP, of whom 564 (r-axSpA: 384; nr-axSpA: 179; unconfirmed: 1) were included in the effectiveness analyses. The mean baseline BASDAI was 6.1 in the overall axSpA population and r-axSpA and nr-axSpA subpopulations. At week 52, the mean (s.d.) change in BASDAI was -2.9 (2.3; n = 439); for r-axSpA and nr-axSpA, it was -2.9 (2.2; n = 301) and -2.8 (2.4; n = 137), respectively (P <0.0001 for all). Similar improvements were seen across other axSpA disease measures. In total, 37.9% (255/672) patients experienced adverse events, and 1.8% (12/672) experienced ≥1 serious adverse events. CONCLUSION: Improvements observed in signs and symptoms of axSpA following one year of CZP treatment in real-world clinical practice were similar to those from previous randomized clinical trials, with no new safety concerns.

Performance of basophil activation test and specific IgG4 as diagnostic tools in nonspecific lipid transfer protein allergy: Antwerp-Barcelona comparison.

BACKGROUND: Recent studies show that nsLTP sensitization is not limited to the Mediterranean basin and can present diverse clinical phenotypes. It remains challenging to predict clinical outcome when specific IgE antibodies (sIgE) to nsLTPs are present. This study compares both clinical and in vitro allergy characteristics but also diagnostic performance of a basophil activation test (BAT) and sIgG4 in nsLTP-sensitized patients from Antwerp (ANT, Belgium) and Barcelona (BCN, Spain). METHODS: Adult subjects with positive sIgE rPru p 3 and/or rMal d 3 ≥ 0.10 kUA /L (n = 182) and healthy controls (n = 37) were included. NsLTP-sensitized individuals were stratified according to clinical symptoms with peach/apple, respectively. BAT rPru p 3 and rMal d 3 were performed and sIgG4 antibodies to both components quantified. RESULTS: In BCN, only ratios of sIgG4/sIgE rMal d 3 and BAT rMal d 3 (0.001 µg/mL) can identify clinically relevant Mal d 3 sensitization (sensitivity of 60%-63% and a specificity of 75%-67%, respectively). In ANT, only the sIgE/total IgE rPru p 3 ratio shows added value (sensitivity 60% and specificity 83%). Finally, it appears that symptomatic patients in BCN are more sensitive to lower allergen concentrations compared to ANT. In addition, it was shown that ANT patients were more often sensitized to pollen and that specific pollen sources differed between regions. CONCLUSIONS: NsLTP-related allergy profiles and diagnostic performance differ significantly between regions and are component-specific, which makes extrapolation of data difficult to do. In addition, it seems that basophil sensitivity might show geographical differences. Additional research is needed to confirm these findings.

Occupational cannabis exposure and allergy risks.

OBJECTIVES: Cannabis allergy has mainly been described following recreational use but some cases also point to cannabis sensitisation as a result of occupational exposure. As a consequence, little is known on the prevalence and clinical phenotype of occupational cannabis allergy. Therefore, this study aims to explore the allergy-associated health risks of occupational cannabis exposure in Belgian police force personnel. METHODS: 81 participants, active in the police force, reporting regular occupational cannabis exposure during the past 12 months, were included. History was combined with a standardised questionnaire on allergies and cannabis exposure.Basophil activation tests (BATs) with a crude cannabis extract and rCan s 3 were performed. In addition, specific (s)IgE rCan s 3 as well as sIgE to house dust mite, six pollen and three mould allergens were quantified. RESULTS: Although 42% of the participants reported respiratory and/or cutaneous symptoms on occupational cannabis exposure, all cannabis diagnostics were entirely negative, except one symptomatic case demonstrating a borderline result. Furthermore, there is no significant difference between the groups with and without symptoms on cannabis exposure in terms of allergenic sensitisations. CONCLUSIONS: The origins of the reported respiratory and cutaneous symptoms during cannabis exposure remain elusive but are probably due to non-immune reactions. It should be noted that the study was volunteer-based possibly reflecting an excessive number of symptomatic individuals. Nevertheless, as only one participant reported using fully protective gear, much improvement is needed for reducing the number of symptoms reported on duty, independent of their origin.

Influence of Morphine and Naloxone on Pain Modulation in Rheumatoid Arthritis, Chronic Fatigue Syndrome/Fibromyalgia, and Controls: A Double-Blind, Randomized, Placebo-Controlled, Cross-Over Study.

BACKGROUND: Impaired pain inhibitory and enhanced pain facilitatory mechanisms are repeatedly reported in patients with central sensitization pain. However, the exact effects of frequently prescribed opioids on central pain modulation are still unknown. METHODS: A randomized, double-blind, placebo-controlled cross-over trial was carried out. Ten chronic fatigue syndrome (CFS)/fibromyalgia (FM) patients, 11 rheumatoid arthritis (RA) patients and 20 controls were randomly allocated to the experimental (10 mg morphine or 0.2 mg/mL Naloxone) and placebo (2 mL Aqua) group. Pressure pain thresholds (PPTs) and temporal summation at the Trapezius and Quadriceps were assessed by algometry. Conditioned pain modulation (CPM) efficacy and deep tissue pain pressure were assessed by adding ischemic occlusion at the opposite upper arm. RESULTS: Deep tissue pain pressure was lower and temporal summation higher in CFS/FM (P = 0.002 respectively P = 0.010) and RA patients (P = 0.011 respectively P = 0.047) compared to controls at baseline. Morphine had only a positive effect on PPTs in both patient groups (P time = 0.034). Accordingly, PPTs increased after placebo (P time = 0.015), and no effects on the other pain parameters were objectified. There were no significant effects of naloxone nor nocebo on PPT, deep tissue pain, temporal summation or CPM in the control group. CONCLUSIONS: This study revealed anti-hyperalgesia effects of morphine in CFS/FM and RA patients. Nevertheless, these effects were comparable to placebo. Besides, neither morphine nor naloxone influenced deep tissue pain, temporal summation or CPM. Therefore, these results suggest that the opioid system is not dominant in (enhanced) bottom-up sensitization (temporal summation) or (impaired) endogenous pain inhibition (CPM) in patients with CFS/FM or RA.

CD4+ROR γ t++ and Tregs in a Mouse Model of Diet-Induced Nonalcoholic Steatohepatitis.

BACKGROUND AND AIMS: Inflammatory mediators that cross-talk in different metabolically active organs are thought to play a crucial role in the pathogenesis of Nonalcoholic Steatohepatitis (NASH). This study was aimed at investigating the CD4+RORγt+ T-helper cells and their counterpart, the CD4+CD25+FOXP3+ regulatory T cells in the liver, subcutaneous adipose tissue (SAT), and abdominal adipose tissue (AAT) in a high fat diet (HFD) mouse model. METHODS: C57BL6 mice were fed a HFD or a normal diet (ND). Liver enzymes, metabolic parameters, and liver histology were assessed. The expression of CD4+RORγt+ cells and regulatory T cells in different organs (blood, liver, AAT, and SAT) were analyzed by flow cytometry. Cytokine and adipokine tissue expression were studied by RT-PCR. RESULTS: Mice fed a HFD developed NASH and metabolic alterations compared to normal diet. CD4+RORγt++ cells were significantly increased in the liver and the AAT while an increase of regulatory T cells was observed in the SAT of mice fed HFD compared to ND. Inflammatory cytokines were also upregulated. CONCLUSIONS: CD4+RORγt++ cells and regulatory T cells are altered in NASH with a site-specific pattern and correlate with the severity of the disease. These site-specific differences are associated with increased cytokine expression.

Endogenous pain modulation in response to exercise in patients with rheumatoid arthritis, patients with chronic fatigue syndrome and comorbid fibromyalgia, and healthy controls: a double-blind randomized controlled trial.

OBJECTIVE: Temporal summation (TS) of pain, conditioned pain modulation (CPM), and exercise-induced analgesia (EIA) are often investigated in chronic pain populations as an indicator for enhanced pain facilitation and impaired endogenous pain inhibition, respectively, but interactions are not yet clear both in healthy controls and in chronic pain patients. Therefore, the present double-blind randomized placebo-controlled study evaluates pains cores, TS, and CPM in response to exercise in healthy controls, patients with chronic fatigue syndrome and comorbid fibromyalgia (CFS/FM), and patients with rheumatoid arthritis (RA), both under placebo and paracetamol condition. METHODS: Fifty-three female volunteers - of which 19 patients with CFS/FM, 16 patients with RA, and 18 healthy controls - underwent a submaximal exercise test on a bicycle ergometer on 2 different occasions (paracetamol vs. placebo), with an interval of 7 days. Before and after exercise, participants rated pain intensity during TS and CPM. RESULTS: Patients with rheumatoid arthritis showed decreased TS after exercise, both after paracetamol and placebo (P < 0.05). In patients with CFS/FM, results were less univocal. A nonsignificant decrease in TS was only observed after taking paracetamol. CPM responses to exercise are inconclusive, but seem to worsen after exercise. No adverse effects were seen. CONCLUSION: This study evaluates pain scores, TS, and CPM in response to submaximal exercise in 2 different chronic pain populations and healthy controls. In patients with RA, exercise had positive effects on TS, suggesting normal EIA. In patients with CFS/FM, these positive effects were only observed after paracetamol and results were inconsistent.

Cor a 14: missing link in the molecular diagnosis of hazelnut allergy?

BACKGROUND: Hazelnut allergy shows distinct clinical patterns that can be predicted through component-resolved diagnosis. However, identification of sensitization profiles remains incomplete. METHODS: Sera of 75 patients allergic to hazelnuts, 14 infants with atopic dermatitis (AD) sensitized to hazelnuts, 15 hazelnut-tolerant individuals with specific IgE (sIgE) to hazelnuts and 15 healthy control individuals were tested for sIgE reactivity to rCor a 1.04, rCor a 8, nCor a 9, nCor a 11, rCor a 14, rBet v 1, rBet v 2 and cross-reactive carbohydrate determinants (CCDs). RESULTS: Sensitization to Cor a 14 was observed in 18 out of 20 preschool children, 8 out of 10 school-aged children and 2 out of 7 adults with generalized reactions and in 3 out of 14 infants with AD. Only 2 out of 38 patients with an oral allergy syndrome (OAS) were sensitized to Cor a 14. No sensitization to Cor a 14 was observed in the group of hazelnut-tolerant and healthy control individuals. Sensitization to Cor a 1.04 was seen in 36 out of 38 OAS patients and in 14 out of 37 patients with generalized reactions. However, only 3 patients with generalized reactions were monosensitized to Cor a 1.04. Sensitization to Cor a 9 was observed in 26 out of 37 patients with generalized reactions and in 4 out of 14 infants with AD. Sensitization to Cor a 11, Cor a 8, rBet v 2 and CCDs was rare. CONCLUSIONS: Sensitization to Cor a 14 can have early onset and shows age-related variations. Together with Cor a 9, Cor a 14 enables us to correctly identify almost 90% of children with generalized reactions to hazelnut.

Infrapatellar fat pad of patients with end-stage osteoarthritis inhibits catabolic mediators in cartilage.

OBJECTIVE: Adipose tissue is known to release inflammatory cytokines and growth factors. In this exploratory study, the authors examined whether the infrapatellar fat pad (IPFP) closely located to cartilage in the knee joint can affect cartilage metabolism. In addition, the authors analysed whether the macrophage types present in IPFP could explain the effect on cartilage. METHODS: IPFP explants obtained during total knee replacement of 29 patients with osteoarthritis (OA) were used to make fat-conditioned medium (FCM). Explants of bovine cartilage were cultured with or without FCM. Nitric oxide (NO) and glycosaminoglycan release and gene expression of matrix-degrading enzymes in cartilage were analysed. To stimulate catabolic processes in the cartilage, the authors added interleukin 1ß, and the effect of six FCMs was evaluated. The presence of different types of macrophages (CD68+, CD86+ and CD206+) in OA IPFPs was compared with subcutaneous adipose tissue samples and IPFP samples from patients with an anterior cruciate ligament rupture. RESULTS: FCM alone reduced NO and glycosaminoglycan release and matrix metalloproteinase (MMP)1 gene expression by the cartilage. Moreover, when catabolic conditions were enhanced with interleukin 1ß, FCM inhibited NO production as well as MMP1 and MMP3 gene expression and increased collagen type II gene expression. Significantly more CD206+ cells were present in OA IPFP samples than in subcutaneous fat or anterior cruciate ligament IPFP samples. CONCLUSION: In contrast to the authors' expectations, medium conditioned by end-stage OA IPFP inhibited catabolic processes in cartilage. CD206+ cells present in the IPFPs used for making the FCM might have contributed to the inhibition of catabolic processes in the cartilage.

Cytokine production by infrapatellar fat pad can be stimulated by interleukin 1ß and inhibited by peroxisome proliferator activated receptor α agonist.

BACKGROUND: Infrapatellar fat pad (IPFP) might be involved in osteoarthritis (OA) by production of cytokines. It was hypothesised that production of cytokines is sensitive to environmental conditions. OBJECTIVES: To evaluate cytokine production by IPFP in response to interleukin (IL)1ß and investigate the ability to modulate this response with an agonist for peroxisome proliferator activated receptor α (PPARα), which is also activated by lipid-lowering drugs such as fibrates. METHODS: Cytokine secretion of IPFP was analysed in the medium of explant cultures of 29 osteoarthritic patients. IPFP (five donors) and synovium (six donors) were cultured with IL-1ß and PPARα agonist Wy14643. Gene expression of IL-1ß, monocyte chemoattractant protein (MCP1), (IL-6, tumour necrosis factor (TNF)α, leptin, vascular endothelial growth factor (VEGF), IL-10, prostaglandin-endoperoxide synthase (PTGS)2 and release of TNFα, MCP1 and prostaglandin E(2) were compared with unstimulated IPFP and synovium explants. RESULTS: IPFP released large amounts of inflammatory cytokines, adipokines and growth factors. IL-1ß increased gene expression of PTGS2, TNFα, IL-1ß, IL-6 and VEGF and increased TNFα release in IPFP. MCP1, leptin, IL-10 gene expression and MCP1, leptin and PGE(2) release did not increase significantly. Synovium responded to IL-1ß similarly to IPFP, except for VEGF gene expression. Wy14643 decreased gene expression of PTGS2, IL-1ß, TNFα, MCP1, VEGF and leptin in IPFP explants and IL-1ß, TNFα, IL-6, IL-10 and VEGF in synovium that responded to IL-1ß. CONCLUSION: IPFP is an active tissue within the joint. IPFP cytokine production is increased by IL-1ß and decreased by a PPARα agonist. The effects were similar to effects seen in synovium. Fibrates may represent a potential disease-modifying drug for OA by modulating inflammatory properties of IPFP and synovium.

In the mind or in the brain? Scientific evidence for central sensitisation in chronic fatigue syndrome.

BACKGROUND: Central sensitisation entails several top-down and bottom-up mechanisms, all contributing to the hyperresponsiveness of the central nervous system to a variety of inputs. In the late nineties, it was first hypothesised that chronic fatigue syndrome (CFS) is characterised by hypersensitivity of the central nervous system (i.e. central sensitisation). Since then, several studies have examined central sensitisation in patients with CFS. This study provides an overview of such studies. MATERIALS AND METHODS: Narrative review. RESULTS: Various studies showed generalised hyperalgesia in CFS for a variety of sensory stimuli, including electrical stimulation, mechanical pressure, heat and histamine. Various tissues are affected by generalised hyperalgesia: the skin, muscle tissue and the lungs. Generalised hyperalgesia in CFS is augmented, rather than decreased, following various types of stressors like exercise and noxious heat pain. Endogenous inhibition is not activated in response to exercise and activation of diffuse noxious inhibitory controls following noxious heat application to the skin is delayed. CONCLUSIONS: The observation of central sensitisation in CFS is in line with our current understanding of CFS. The presence of central sensitisation in CFS corroborates with the presence of several psychological influences on the illness, the presence of infectious agents and immune dysfunctions and the dysfunctional hypothalamus-pituitary-adrenal axis as seen in these severely debilitated patients.

Overexpression of FcεRI on Bone Marrow Mast Cells, but Not MRGPRX2, in Clonal Mast Cell Disorders With Wasp Venom Anaphylaxis.

Background: Uncertainties remain about the molecular mechanisms governing clonal mast cell disorders (CMCD) and anaphylaxis. Objective: This study aims at comparing the burden, phenotype and behavior of mast cells (MCs) and basophils in patients with CMCD with wasp venom anaphylaxis (CMCD/WVA+), CMCD patients without anaphylaxis (CMCD/ANA-), patients with an elevated baseline serum tryptase (EBST), patients with wasp venom anaphylaxis without CMCD (WVA+) and patients with a non-mast cell haematological pathology (NMHP). Methods: This study included 20 patients with CMCD/WVA+, 24 with CMCD/ANA-, 19 with WVA+, 6 with EBST and 5 with NMHP. We immunophenotyped MCs and basophils and compared baseline serum tryptase (bST) and both total and venom specific IgE in the different groups. For basophil studies, 13 healthy controls were also included. Results: Higher levels of bST were found in CMCD patients with wasp venom anaphylaxis, CMCD patients without anaphylaxis and EBST patients. Total IgE levels were highest in patients with wasp venom anaphylaxis with and without CMCD. Bone marrow MCs of patients with CMCD showed lower CD117 expression and higher expression of CD45, CD203c, CD63, CD300a and FcεRI. Within the CMCD population, patients with wasp venom anaphylaxis showed a higher expression of FcεRI as compared to patients without anaphylaxis. Expression of MRGPRX2 on MCs did not differ between the study populations. Basophils are phenotypically and functionally comparable between the different patient populations. Conclusion: Patients with CMCD show an elevated burden of aberrant activated MCs with a significant overexpression of FcεRI in patients with a wasp venom anaphylaxis.

Young infants with atopic dermatitis can display sensitization to Cor a 9, an 11S legumin-like seed-storage protein from hazelnut (Corylus avellana).

Allergy to hazelnut (Corylus avellana) can be severe and occur at young age. Atopic dermatitis (AD) can involve sensitization to various foods. The objective is to investigate the pattern of hazelnut sensitization in infants with AD. Sera of 34 infants all under 1 year of age and suffering from AD were selected according to prior specific IgE results. Twenty-nine infants were sensitized to traditional food allergens, five were not. From the 29 infants with a sensitization to at least one food allergen, 20 demonstrated IgE reactivity to hazelnut. All sera were analyzed with the allergen microarray immunoassay (ImmunoCAP ISAC). Twelve (60%) of the children with IgE reactivity to hazelnut demonstrated sensitization to Cor a 9, the 11S legumin-like seed-storage protein from hazelnut. In these infants, no sensitization to Cor a 1, the homologue of the major birch pollen allergen Bet v 1 (Betula verrucosa), or the lipid transfer protein (Cor a 8) from hazelnut was demonstrable. Half of the children sensitized to Cor a 9 demonstrated IgE reactivity to its homologue in peanut (Arachis hypogaea; Ara h 3) from which five were also sensitized to Gly m 6 from soy (Glycine max). None of the infants with AD without IgE reactivity to hazelnut demonstrated sensitization to Cor a 1, 8, or 9. In conclusion, young infants with atopic dermatitis sensitized to hazelnut can already display IgE reactivity to Cor a 9, a potentially dangerous hazelnut component. The mechanism(s) of this early sensitization and its clinical significance remain elusive.

Culturing cells with mast cell phenotype and function: Comparison of peripheral blood and bone marrow as a source.

BACKGROUND: Studies on the mechanisms that govern mast cell (MC) functions are hindered by the difficulties in isolating sufficient numbers of these tissue-resident cells. Therefore, many research groups use cultured human MCs obtained out of progenitor cells. However, these culture methods significantly differ regarding primary source material, culture durations and conditions. Consequently, the finally obtained cells are likely to exhibit morphological, phenotypical and/or functional heterogeneity. OBJECTIVE: To compare the phenotype and functionality of cells cultured from peripheral blood and bone marrow progenitor cells from patients with suspected clonal MC disease. These cells are designated as PBCMCs and BMCMCs, respectively. METHODS: Twenty paired PBCMCs and BMCMCs cultures starting from CD34+ progenitor cells were compared. Cells were cultured for 4 weeks. Phenotyping included Giemsa and CD117 staining and flow cytometric staining for CD117, CD203c, FcεRI, MRGPRX2, CD300a, CD32, CD63 and CD25. Functional assessment included measurement of the up-regulation of CD63 after cross-linking of the high affinity receptor for IgE (FcεRI) with anti-FcεRI and ligation of MRGPRX2 with substance P. RESULTS: PBCMCs and BMCMCs are phenotypically comparable. Functionally, after activation with anti-FcεRI and substance P, PBCMCs and BMCMCs show similar up-regulation of the lysosomal degranulation marker CD63. However, the yield of PBCMCs is higher than BMCMs and peripheral blood cultures are purer than bone marrow cultures. CONCLUSION: PBCMCs are an attractive alternative to the more difficult to obtain BMCMCs for the exploration of the complex mechanisms that govern IgE- and MRGPRX2-dependent MC activation and degranulation. Unlike BMCMCs, PBCMCs are easily accessible and enable repetitive analyses.

Increased IL-17 production by peripheral T helper cells after tumour necrosis factor blockade in rheumatoid arthritis is accompanied by inhibition of migration-associated chemokine receptor expression.

OBJECTIVES: The contribution of IL-17-producing Th17 cells to the pathogenesis of T-cell-mediated inflammatory disorders such as RA and atopic dermatitis (AD) has to be viewed in relation to the role of Th1/Th2 cells and long-recognized key cytokines like TNF. We aimed to study the frequency and migration-associated phenotype of peripheral Th17, Th1 and Th2 cells in healthy individuals, RA and AD patients, and to study the influence of anti-TNF therapy in RA. METHODS: Intracellular IL-17, IFN-γ and IL-4 production and CC-chemokine receptor CCR4 and CCR6 expression were analysed flow cytometrically in peripheral memory Th cells from healthy individuals, AD and RA patients. The latter were grouped by disease activity and presence or absence of adalimumab therapy. In RA patients initiating anti-TNF therapy, cytokine production by in vitro-stimulated peripheral mononuclear cells was measured by cytometric bead array. RESULTS: The peripheral Th17 cell frequency is elevated in AD but not in RA. In RA, Th17 cells and IL-17 production increase after anti-TNF therapy, irrespective of disease activity. Th1 cells and IFN-γ production are elevated in remission and under anti-TNF therapy. CCR6 expression is up-regulated in Th17 cells, but RA patients in remission under anti-TNF therapy have significantly lower expression than those with active disease. CONCLUSIONS: The increase in peripheral Th17 cells in RA patients after anti-TNF therapy is accompanied by a decrease in Th17-specific CCR6 expression, which might prevent homing of these potentially pro-inflammatory cells to the synovium.

Flow Cytometric Allergy Diagnosis: Basophil Activation Techniques.

The basis of flow cytometric allergy diagnosis is the quantification of changes in the expression of basophilic surface membrane markers (Ebo et al., Clin Exp Allergy 34: 332-339, 2004). Upon encountering specific allergens recognized by surface receptor FcεRI-bound IgE, basophils not only secrete and generate quantifiable bioactive mediators but also upregulate the expression of different markers (e.g., CD63, CD203c) which can be detected by multicolor flow cytometry using specific monoclonal antibodies (Ebo et al., Cytometry B Clin Cytom 74: 201-210, 2008). Here, we describe two flow cytometry-based protocols which allow the detection of surface marker activation (Method 1) and changes in intragranular histamine (Method 2), both reflecting different facets of basophil activation.