The data project: a shared approach between stakeholders of the healthcare system in definition of a therapeutic algorithm for inflammatory arthritis

Rheumatic musculoskeletal diseases or RMD [rheumatoid arthritis (RA) and spondyloarthritis (SpA)] are systemic inflammatory diseases for which there are no biomarkers capable of predicting treatments with a higher likelihood of response in naive patients. In addition, the expiration of the anti-TNF blocking drugs' patents has resulted in the availability of anti-TNF biosimilar drugs with the same efficacy and safety than originators but at significantly reduced prices. To guarantee a personalized therapeutic approach to RMD treatment, a board of rheumatologists and stakeholders from the Campania region, Italy, developed a clinically applicable arthritis therapeutic algorithm to guide rheumatologists (DATA project). The general methodology relied on a Delphi technique forecast to produce a set of statements that summarized the experts' consensus. Selected clinical scenarios were discussed in light of the available evidence, and there were two rounds of voting on the therapeutic approaches. Separate discussions were held regarding rheumatoid arthritis, psoriatic arthritis, and ankylosing spondylitis. The decision-making factors for each disease were clinical presentation, demographics, and comorbidities. In this paper, we describe a virtuous process between rheumatologists and healthcare system stakeholders that resulted in the development of a shared therapeutic algorithm for RMD patients naive to bDMARDs.

Genetically encoded Runx3 and CD4+ intestinal epithelial lymphocyte deficiencies link SKG mouse and human predisposition to spondyloarthropathy

Disturbances in immune regulation, intestinal dysbiosis and inflammation characterize ankylosing spondylitis (AS), which is associated with RUNX3 loss-of-function variants. ZAP70^W163C mutant (SKG) mice have reduced ZAP70 signaling, spondyloarthritis and ileitis. In small intestine, Foxp3⁺ regulatory T cells (Treg) and CD4⁺CD8αα⁺TCRαβ⁺ intraepithelial lymphocytes (CD4-IEL) control inflammation. TGF-β and retinoic acid (RA)-producing dendritic cells and MHC-class II⁺ intestinal epithelial cells (IEC) are required for Treg and CD4-IEL differentiation from CD4⁺ conventional or Treg precursors, with upregulation of Runx3 and suppression of ThPOK. We show in SKG mouse ileum, that ZAP70^W163C or ZAP70 inhibition prevented CD4-IEL but not Treg differentiation, dysregulating Runx3 and ThPOK. TGF-β/RA-mediated CD4-IEL development, T-cell IFN-γ production, MHC class-II⁺ IEC, tissue-resident memory T-cell and Runx3-regulated genes were reduced. In AS intestine, CD4-IEL were decreased, while in AS blood CD4⁺CD8⁺ T cells were reduced and Treg increased. Thus, genetically-encoded TCR signaling dysfunction links intestinal T-cell immunodeficiency in mouse and human spondyloarthropathy.

The evaluation of an inorganic-organic poly(carborane-siloxane-arylacetylene) hybrid resin system

The realization of aerospace vehicle technologies demanding extreme service conditions is facilitated by the development of materials with greater oxidative stability at high temperatures. Thermal performance of polymer composites can be increased by incorporating a hybrid (organic-inorganic) resin as a thermal barrier coating. One such resin system, meta-poly (carborane-siloxane-arylacetylene) ( m-PCSAA), developed by the U.S. Naval Research Laboratory, shows potential for such application and is further investigated in this work. The resin has a low viscosity (0.1 Pa s) with large processing window (2.5 h) from 100°C to 230°C. These processing characteristics are advantageous for infusion processes or the inclusion of fillers for coating applications. Curing was accomplished in two stages, corresponding to two exothermic reactions. After the first curing stage, the resin exhibits elastomeric behavior, and after the second curing stage is rigid with a high glass transition temperature (∼330°C). The materials exhibited high char yields (89%) in air at 1000°C and may be useful in space or for attritable technology. No cracks were observed during long-term service at 288°C, but significant degradation and cracking were observed after aging at 316°C. The materials exhibited high coefficients of thermal expansion; 186.9 and 168.6 μm/(m∙°C) after first and second curing stage respectively. Similar to epoxies and polyimides, the resin acquired up to 3% moisture at 70°C and 85% relative humidity.

POS0031 FUNCTIONAL GENOMICS INVESTIGATION OF THE ANKYLOSING SPONDYLITIS ASSOCIATED LOCUS RUNX3

Background

Ankylosing Spondylitis (AS), is a highly heritable disease with >100 genomic loci incriminated. Among these, RUNX3, a transcription factor (TF) involved in diverse immunological processes, is robustly (10−15) associated. [1] We have extensively investigated the single nucleotide polymorphism (SNP) rs4648889 located in a 2kb regulatory locus upstream of the RUNX3 promoter. We have demonstrated that the association between AS and this SNP can be explained by allele-specific effects on TF recruitment (including IRF4, IRF5 and the NuRD complex) that alter gene expression, specifically in CD8+ T-cells, and having a crucial role in CD8+ T-cells function. [2, 3]

Further, we have recently shown a clear chromatin looping event between the region encompassing SNP rs4648889 and the RUNX3 promoter confirming the functional role of this genetic variant. [4]

Objectives

The purpose of this work is: (1) to better characterise the chromatin looping landscape of the whole AS-associated RUNX3 genomic locus and (2) to determine the single-cell expression of the RUNX3-related genes identified previously [2, 3] in CD8+ T-cells lymphocytes.

Methods

(1) Chromosome conformation capture (3C) technique followed by qPCR was performed to define the chromatin looping events at the RUNX3 genomic locus in relevant cell lines, including Jurkat T-cells and U937 monocytes-like cells. (2) 10X Chromium single-cell (sc) sequencing was performed to define RUNX3 and RUNX3-related genes expression profile in CD8+ T cells obtained from AS cases.

Results

(1) In addition to the recent results published, [4] 3C-qPCR experiments revealed a high interaction frequency between the distal promoter of RUNX3 and an intronic region (called Int2), overlapping open chromatin and TF binding sites. This was highly reproducible in both cell lines analysed. (2) Four different clusters were identified in CD8+ T-cells obtained from AS peripheral blood via 10x sc-seq based on the expression of RUNX3. Five other genes (TBX21, EOMES, CHD4, IRF5 and IKZF3) previously identified [2] were considered: cluster 1 showed a strong co-expression for RUNX3, IKZF3, CHD4 and EOMES. Further analysis is required to better characterize this subpopulation.

Conclusion

The AS-associated RUNX3 genomic locus has a plausible functional role in AS, probably by regulating gene transcription and DNA looping. These observations are critically important in defining dysregulated pathways and potential therapeutic drug targets.

References

[1]IGAS et al. Nat Genet. 2013 Jul;45(7):730-8.

[2]Vecellio M. et al, Ann Rheum Dis. 2016 Aug;75(8):1534-40.

[3]Vecellio M. et al, Arthritis Rheumatol 2020. doi: 10.1002/art.41628.

[4]Cohen CJ. et al, Front Genet 2022 doi.org/10.3389/fgene.2021.741867.

Disclosure of Interests

Carla Cohen: None declared, Davide Simone: None declared, Carlo Selmi Speakers bureau: Speakers fee (AbbVie, Amgen, Alfa-Wassermann, Biogen, Celgene, Eli-Lilly, Gilead, Janssen, MSD, Novartis, Pfizer, Sanofi-Genzyme), Consultant of: Consulting (AbbVie, Amgen, Alfa-Wassermann, Biogen, Celgene, Eli-Lilly, Gilead, Janssen, MSD, Novartis, Pfizer, Sanofi-Genzyme), Grant/research support from: Research support (AbbVie, Amgen, Janssen, Pfizer), aul Bowness Grant/research support from: Regeneron, Celgene/BMS and GSK, Paul Bryan Wordsworth: None declared, Matteo Vecellio: None declared

Single cell analysis of spondyloarthritis regulatory T cells identifies distinct synovial gene expression patterns and clonal fates

Regulatory T cells (Tregs) play an important role in controlling inflammation and limiting autoimmunity, but their phenotypes at inflammatory sites in human disease are poorly understood. We here analyze the single-cell transcriptome of >16,000 Tregs obtained from peripheral blood and synovial fluid of two patients with HLA-B27+ ankylosing spondylitis and three patients with psoriatic arthritis, closely related forms of inflammatory spondyloarthritis. We identify multiple Treg clusters with distinct transcriptomic profiles, including, among others, a regulatory CD8+ subset expressing cytotoxic markers/genes, and a Th17-like RORC+ Treg subset characterized by IL-10 and LAG-3 expression. Synovial Tregs show upregulation of interferon signature and TNF receptor superfamily genes, and marked clonal expansion, consistent with tissue adaptation and antigen contact respectively. Individual synovial Treg clones map to different clusters indicating cell fate divergence. Finally, we demonstrate that LAG-3 directly inhibits IL-12/23 and TNF secretion by patient-derived monocytes, a mechanism with translational potential in SpA. Our detailed characterization of Tregs at an important inflammatory site illustrates the marked specialization of Treg subpopulations.

ANTINOCICEPTIVE TOLERANCE TO CANNABINOIDS IN ADULT MALE MICE: A PILOT STUDY

Over the past two decades, numerous tools have been developed to study the endocannabinoid system. Studies show the potential effectiveness of endocannabinoids for the relief of pain and neurological disorders. However, global targeting of the endocannabinoid system has also been associated with unwanted outcomes, including deleterious effects on cognitive and emotional functions, the development of tolerance and dependence, and withdrawal symptoms after drug cessation in humans. The main objective of the present study was to determine whether male mice develop tolerance to delta-9-tetrahydro-cannabinol (THC) and cannabinolic acid (CBNA)-induced antinociception with long-term treatment. Using behavioral tests of mechanical and thermal nociception, we found that systemic (intraperitoneal, i.p.) administration of THC and CBNA resulted in strong antinociception on the first day of the experiment. However, over the next four days, the behavior indices of antinociception to mechanical and thermal stimuli gradually decreased, indicating the development of tolerance following systemic administration of these drugs. Thus, the two main components of cannabis, THC and CBNA, are characterized by the development of tolerance in mice as a result of their repeated i.p. administration.

Genetic and Environmental Determinants of T Helper 17 Pathogenicity in Spondyloarthropathies

In Spondyloarthropathies (SpA), a common group of immune-mediated diseases characterised by excessive inflammation of musculo-skeletal structures and extra-articular organs, T helper 17 (Th17) cells are widely considered the main drivers of the disease. Th17 are able to modulate their genes according to the immune environment: upon differentiation, they can adopt either housekeeping, anti-bacterial gene modules or inflammatory, pathogenic functions, and only the latter would mediate immune diseases, such as SpA. Experimental work aimed at characterising Th17 heterogeneity is largely performed on murine cells, for which the in vitro conditions conferring pathogenic potential have been identified and replicated. Interestingly, Th17 recognising different microorganisms are able to acquire specific cytokine signatures. An emerging area of research associates this heterogeneity to the preferential metabolic needs of the cell. In summary, the tissue environment could be determinant for the acquisition of pathogenetic features; this is particularly important at barrier sites, such as the intestine, considered one of the key target organs in SpA, and likely a site of immunological changes that initiate the disease. In this review, we briefly summarise genetic, environmental and metabolic factors that could explain how homeostatic, anti-microbial Th17 could turn into disease-causing cells in Spondyloarthritis.

Real-life efficacy of guselkumab in patients with early psoriatic arthritis

OBJECTIVES

To assess the efficacy of the novel anti-IL-23 monoclonal antibody Guselkumab in a real-life observational cohort of patients with early Psoriatic arthritis (PsA).

METHODS

We conducted an observational study on patients with early PsA followed by the joint dermatology-rheumatology clinics of two Italian centres starting therapy with guselkumab for severe skin involvement. Each patient was evaluated at baseline and every 24 weeks for one year, recording DAPSA, PASI, VAS Pain, VAS Prutitus, Patient's Global Assessment (PtGA) and assessing DAPSA response.

RESULTS

Twenty-four patients were recruited (16 women). The mean duration of skin disease was 12.5 years [CI 8; 17], but all patients had a shorter articular disease duration, 21.29 months [CI 15.9; 26.68]. At baseline, all patients displayed a moderate cutaneous disease with a mean PASI of 15.2 [CI 11.7-18.6] and high disease activity, characterized by mean DAPSA of 26.84 (CI 22.49-31.19). An inflammatory low back pain ware reported by five patients (20%) with a mean BASDAI 5.1 [4,38-5,85] at baseline. The majority of guselkumab-treated patients (N = 18; 75%) reached DAPSA remission or DAPSA low disease activity (LDA) after six months. Seventeen out of 24 patients completed 12 months of treatment, 11 of them (65%) in LDA, 6 (35%) in remission. All patients with axial disease reported improvement of inflammatory low back pain at week 24 with a mean BASDAI 2.98 [2,18- 3,77]. No significant side effects were reported.

CONCLUSIONS

Real-life data on a cohort of early PsA patients confirm the efficacy and safety of Guselkumab on peripheral and axial manifestations.

OP0032 SINGLE CELL ANALYSIS OF SPONDYLOARTHRITIS REGULATORY T CELLS IDENTIFIES DISTINCT SYNOVIAL GENE EXPRESSION PATTERNS AND CLONAL FATES

Background:

Regulatory T cells (Tregs) play an important role in controlling inflammation and limiting autoimmunity, but their phenotypes at inflammatory sites in human disease are poorly understood. Whilst the phenotype and transcriptional profile of Tregs have been studied in some immune mediated conditions, they have been little studied (especially at the single cell level) in synovial fluid in the course of inflammatory arthritis. In Spondyloarthritis (SpA), in particular, where pathogenesis and inflammation is driven by dysregulated effector immunity, the role of the regulatory arm of immunity is largely unknown.

Objectives:

We aimed to draw an atlas of Tregs in the context of SpA joint inflammation using single cell RNA sequencing of blood and SF Tregs of patients with Ankylosing Spondylitis (AS) and Psoriatic Arthritis (PsA). Functionally distinct specialised Treg subtypes, and specific changes in transcriptional profile occurring in synovial fluid Tregs, providing an insight on Treg adaptation during inflammation. Furthermore, by coupling gene expression analysis with TCR sequencing, we aimed to describe clonally expanded and likely antigen-driven Tregs in the SF.

Methods:

Fluorescent activated cell sorting (FACS) was used to isolate 13,400 memory CD3+ CD45RA-ve CD25 + 127low Tregs from the blood and synovial fluid (SF) of 2 patients with HLA-B27+ AS presenting with active knee arthritis. Single-cell RNA sequencing (scRNA-seq) using 5’ V(D)J 10x Genomics technology allowed both transcriptional definition of Tregs, and exploration of their immune TCR repertoire. Findings were compared to >3,000 SF and blood Tregs from 3 patients with olygoarticular PsA 1. Multicolor flow cytometry and in vitro cell-based assays using patient-derived cells were used to confirm and expand, at protein and functional level, the findings that emerged from the gene expression analysis.

Results:

We report a large scRNAseq dataset (approx. 17,000 cells) comparing Tregs from SpA blood and joints. We identify multiple Treg clusters with distinct transcriptomic profiles, including, among others, a regulatory CD8+ subset expressing cytotoxic markers/genes, and a Th17-like RORC+ Treg subset characterized by IL-10 and LAG-3 expression. Synovial Tregs show upregulation of interferon signature and TNF receptor superfamily genes, and marked clonal expansion, consistent with tissue adaptation and antigen contact respectively. Individual synovial Treg clones map to different clusters indicating cell fate divergence. Finally, we demonstrate that LAG-3 directly inhibits IL-12/23 and TNF secretion by patient-derived monocytes, a mechanism with translational potential in SpA.

Conclusion:

Our detailed characterization of Tregs at an important inflammatory site illustrates the marked specialization of Treg subpopulations and identifies a broad transcriptional profile upregulated across all synovial regulatory cells. Our TCR analysis provides evidence of Treg clonal expansion, which may be driven by antigen, and confirms functional specialisation of individual clones. We also propose a new insight into a Treg functional mechanism through LAG-3 that suggests a novel therapeutic approach to immune-driven diseases.

References:

[1]Penkava et al., Nature Communications, 2020

Disclosure of Interests:

Davide Simone: None declared, Frank Penkava: None declared, Anna Ridley: None declared, Stephen Sansom: None declared, Hussein Al Mossawi Employee of: UCB, Paul Bowness Grant/research support from: Regeneron, Celgene/BMS and GSK

Novel immune cell phenotypes in spondyloarthritis pathogenesis

Spondyloarthritis (SpA) is a heterogeneous group of chronic inflammatory diseases of unknown etiology. Over time, the plethora of cellular elements involved in its pathogenesis has progressively enriched together with the definition of specific cytokine pathways. Recent evidence suggests the involvement of new cellular mediators of inflammation in the pathogenesis of SpA or new subgroups of known cellular mediators. The research in this sense is ongoing, and it is clear that this challenge aimed at identifying new cellular actors involved in the perpetuation of the inflammatory process in AxSpA is not a mere academic exercise but rather aims to define a clear cellular hierarchy. Such a definition could pave the way for new targeted therapies, which could interfere with the inflammatory process and specific pathways that trigger immune system dysregulation and stromal cell activity, ultimately leading to significant control of the inflammation and new bone formation in a significant number of patients. In this review, we will describe the recent advances in terms of new cellular actors involved in the pathogenesis of SpA, focusing our attention on stromal cells and innate and adaptive immunity cells.

Single-cell sequencing reveals clonal expansions of pro-inflammatory synovial CD8 T cells expressing tissue-homing receptors in psoriatic arthritis

Psoriatic arthritis (PsA) is a debilitating immune-mediated inflammatory arthritis of unknown pathogenesis commonly affecting patients with skin psoriasis. Here we use complementary single-cell approaches to study leukocytes from PsA joints. Mass cytometry demonstrates a 3-fold expansion of memory CD8 T cells in the joints of PsA patients compared to peripheral blood. Meanwhile, droplet-based and plate-based single-cell RNA sequencing of paired T cell receptor alpha and beta chain sequences show pronounced CD8 T cell clonal expansions within the joints. Transcriptome analyses find these expanded synovial CD8 T cells to express cycling, activation, tissue-homing and tissue residency markers. T cell receptor sequence comparison between patients identifies clonal convergence. Finally, chemokine receptor CXCR3 is upregulated in the expanded synovial CD8 T cells, while two CXCR3 ligands, CXCL9 and CXCL10, are elevated in PsA synovial fluid. Our data thus provide a quantitative molecular insight into the cellular immune landscape of psoriatic arthritis.

Progress in our understanding of the pathogenesis of ankylosing spondylitis

AS is a common rheumatic condition characterized by inflammation and new bone formation. The pathogenesis of AS is likely multifactorial and has not been fully elucidated to date. A major genetic role has been demonstrated. The strongest genetic association is with HLA B27. Numerous other associated genetic polymorphisms have been identified, including those affecting the type 17 immune pathway, although the precise link between genetics and pathogenesis remains unexplained. Several immunological alterations, together with recent therapeutic advances, support a central role for IL-23- and IL-17-producing immune cells in disease pathogenesis. Recently, perturbations of gut microbiota of AS patients have further catalysed research and offer potential for future therapeutic intervention. In this review we outline the genetic basis of AS and describe the current hypotheses for disease pathogenesis. We synthesize recent experimental research data and clinical studies to support a central role for the type 17/23 immune axis in AS.

Inhibiting ex-vivo Th17 responses in Ankylosing Spondylitis by targeting Janus kinases

Treatment options for Ankylosing Spondylitis (AS) are still limited. The T helper cell 17 (Th17) pathway has emerged as a major driver of disease pathogenesis and a good treatment target. Janus kinases (JAK) are key transducers of cytokine signals in Th17 cells and therefore promising targets for the treatment of AS. Here we investigate the therapeutic potential of four different JAK inhibitors on cells derived from AS patients and healthy controls, cultured in-vitro under Th17-promoting conditions. Levels of IL-17A, IL-17F, IL-22, GM-CSF and IFNγ were assessed by ELISA and inhibitory effects were investigated with Phosphoflow. JAK1/2/3 and TYK2 were silenced in CD4+ T cells with siRNA and effects analyzed by ELISA (IL-17A, IL-17F and IL-22), Western Blot, qPCR and Phosphoflow. In-vitro inhibition of CD4+ T lymphocyte production of multiple Th17 cytokines (IL-17A, IL-17F and IL-22) was achieved with JAK inhibitors of differing specificity, as well as by silencing of JAK1-3 and Tyk2, without impacting on cell viability or proliferation. Our preclinical data suggest JAK inhibitors as promising candidates for therapeutic trials in AS, since they can inhibit multiple Th17 cytokines simultaneously. Improved targeting of TYK2 or other JAK isoforms may confer tailored effects on Th17 responses in AS.

Search for Cosmic-Ray Electron and Positron Anisotropies with Seven Years of Fermi Large Area Telescope Data

The Large Area Telescope on board the Fermi Gamma-ray Space Telescope has collected the largest ever sample of high-energy cosmic-ray electron and positron events since the beginning of its operation. Potential anisotropies in the arrival directions of cosmic-ray electrons or positrons could be a signature of the presence of nearby sources. We use almost seven years of data with energies above 42 GeV processed with the Pass 8 reconstruction. The present data sample can probe dipole anisotropies down to a level of 10^{-3}. We take into account systematic effects that could mimic true anisotropies at this level. We present a detailed study of the event selection optimization of the cosmic-ray electrons and positrons to be used for anisotropy searches. Since no significant anisotropies have been detected on any angular scale, we present upper limits on the dipole anisotropy. The present constraints are among the strongest to date probing the presence of nearby young and middle-aged sources.

miR-10b-5p is a novel Th17 regulator present in Th17 cells from ankylosing spondylitis

OBJECTIVE

To determine the microRNA (miR) signature in ankylosing spondylitis (AS) T helper (Th)17 cells.

METHODS

Interleukin (IL)-17A-producing CD4+ T cells from patients with AS and healthy controls were FACS-sorted for miR sequencing and qPCR validation. miR-10b function was determined by miR mimic expression followed by cytokine measurement, transcriptome analysis, qPCR and luciferase assays.

RESULTS

AS Th17 cells exhibited a miR signature characterised by upregulation of miR-155-5p, miR-210-3p and miR-10b. miR-10b has not been described previously in Th17 cells and was selected for further characterisation. miR-10b is transiently induced in in vitro differentiated Th17 cells. Transcriptome, qPCR and luciferase assays suggest that MAP3K7 is targeted by miR-10b. Both miR-10b overexpression and MAP3K7 silencing inhibited production of IL-17A by both total CD4 and differentiating Th17 cells.

CONCLUSIONS

AS Th17 cells have a specific miR signature and upregulate miR-10b in vitro. Our data suggest that miR-10b is upregulated by proinflammatory cytokines and may act as a feedback loop to suppress IL-17A by targeting MAP3K7. miR-10b is a potential therapeutic candidate to suppress pathogenic Th17 cell function in patients with AS.

Evidence-based algorithm for diagnosis and assessment in psoriatic arthritis: results by Italian DElphi in psoriatic Arthritis (IDEA)

Psoriatic arthritis (PsA) is a chronic inflammatory disease involving skin, peripheral joints, entheses, and axial skeleton. The disease is frequently associated with extrarticular manifestations (EAMs) and comorbidities. In order to create a protocol for PsA diagnosis and global assessment of patients with an algorithm based on anamnestic, clinical, laboratory and imaging procedures, we established a DElphi study on a national scale, named Italian DElphi in psoriatic Arthritis (IDEA). After a literature search, a Delphi poll, involving 52 rheumatologists, was performed. On the basis of the literature search, 202 potential items were identified. The steering committee planned at least two Delphi rounds. In the first Delphi round, the experts judged each of the 202 items using a score ranging from 1 to 9 based on its increasing clinical relevance. The questions posed to experts were How relevant is this procedure/observation/sign/symptom for assessment of a psoriatic arthritis patient? Proposals of additional items, not included in the questionnaire, were also encouraged. The results of the poll were discussed by the Steering Committee, which evaluated the necessity for removing selected procedures or adding additional ones, according to criteria of clinical appropriateness and sustainability. A total of 43 recommended diagnosis and assessment procedures, recognized as items, were derived by combination of the Delphi survey and two National Expert Meetings, and grouped in different areas. Favourable opinion was reached in 100% of cases for several aspects covering the following areas: medical (familial and personal) history, physical evaluation, imaging tool, second level laboratory tests, disease activity measurement and extrarticular manifestations. After performing PsA diagnosis, identification of specific disease activity scores and clinimetric approaches were suggested for assessing the different clinical subsets. Further, results showed the need for investigation on the presence of several EAMs and risk factors. In the context of any area, a rank was assigned for each item by Expert Committee members, in order to create the logical sequence of the algorithm. The final list of recommended diagnosis and assessment procedures, by the Delphi survey and the two National Expert Meetings, was also reported as an algorithm. This study shows results obtained by the combination of a DElphi survey of a group of Italian rheumatologists and two National Expert Meetings, created with the aim of establishing a clinical procedure and algorithm for the diagnosis and the assessment of PsA patients. In order to find accurate and practical diagnostic and assessment items in clinical practice, we have focused our attention on evaluating the different PsA domains. Hence, we conceived the IDEA algorithm in order to address PsA diagnosis and assessment in the context of daily clinical practice. The IDEA algorithm might eventually lead to a multidimensional approach and could represent a useful and practical tool for addressing diagnosis and for assessing the disease appropriately. However, the elaborated algorithm needs to be further investigated in daily practice, for evidencing and proving its eventual efficacy in detecting and staging PsA and its heterogeneous spectrum appropriately.

Disease-modifying Antirheumatic Drugs (DMARD) and Combination Therapy of Conventional DMARD in Patients with Spondyloarthritis and Psoriatic Arthritis with Axial Involvement

Treatment with nonsteroidal antiinflammatory drugs (NSAID) is the recommended first-line therapy in patients with axial spondyloarthritis (axSpA); and for those patients who have persistently active disease, the introduction of tumor necrosis factor-α (TNF-α) inhibitors is indicated. Conventional nonbiological disease-modifying antirheumatic drugs (DMARD), although effective and used in clinical practice for peripheral arthritis, are not recommended. Few studies have been conducted with the aim of evaluating the effect of conventional DMARD, either alone or in combination, in axSpA. As for psoriatic arthritis (PsA), DMARD are widely used, but few trials are available about their effects on axial involvement, which is not often assessed as a primary outcome in clinical trials. In rheumatoid arthritis, combination therapy of 2 or more conventional DMARD appears to confer better response than methotrexate monotherapy, and may even be a viable alternative to TNF-α inhibitors. In peripheral PsA, combination therapy can be used after treatment failure with 1 DMARD, but few studies have been conducted. However, available evidence for the combination of conventional DMARD indicates a lack of any significant benefit on axial symptoms; thus this treatment approach does not represent an effective alternative to anti-TNF-α therapy.

Search for Spectral Irregularities due to Photon-Axionlike-Particle Oscillations with the Fermi Large Area Telescope

We report on the search for spectral irregularities induced by oscillations between photons and axionlike-particles (ALPs) in the γ-ray spectrum of NGC 1275, the central galaxy of the Perseus cluster. Using 6 years of Fermi Large Area Telescope data, we find no evidence for ALPs and exclude couplings above 5×10^{-12}  GeV^{-1} for ALP masses 0.5≲m_{a}≲5  neV at 95% confidence. The limits are competitive with the sensitivity of planned laboratory experiments, and, together with other bounds, strongly constrain the possibility that ALPs can reduce the γ-ray opacity of the Universe.

Resolving the Extragalactic γ-Ray Background above 50 GeV with the Fermi Large Area Telescope

The Fermi Large Area Telescope (LAT) Collaboration has recently released a catalog of 360 sources detected above 50 GeV (2FHL). This catalog was obtained using 80 months of data re-processed with Pass 8, the newest event-level analysis, which significantly improves the acceptance and angular resolution of the instrument. Most of the 2FHL sources at high Galactic latitude are blazars. Using detailed Monte Carlo simulations, we measure, for the first time, the source count distribution, dN/dS, of extragalactic γ-ray sources at E>50  GeV and find that it is compatible with a Euclidean distribution down to the lowest measured source flux in the 2FHL (∼8×10^{-12}  ph cm^{-2} s^{-1}). We employ a one-point photon fluctuation analysis to constrain the behavior of dN/dS below the source detection threshold. Overall, the source count distribution is constrained over three decades in flux and found compatible with a broken power law with a break flux, S_{b}, in the range [8×10^{-12},1.5×10^{-11}]  ph cm^{-2} s^{-1} and power-law indices below and above the break of α_{2}∈[1.60,1.75] and α_{1}=2.49±0.12, respectively. Integration of dN/dS shows that point sources account for at least 86_{-14}^{+16}% of the total extragalactic γ-ray background. The simple form of the derived source count distribution is consistent with a single population (i.e., blazars) dominating the source counts to the minimum flux explored by this analysis. We estimate the density of sources detectable in blind surveys that will be performed in the coming years by the Cherenkov Telescope Array.

Progesterone metabolite allopregnanolone in women with premenstrual syndrome

OBJECTIVE

To evaluate the anxiolytic 3alpha-5alpha-reduced progesterone metabolite allopregnanolone in the luteal phase of the menstrual cycle in women with premenstrual syndrome (PMS) and controls.

METHODS

Thirty-five women with prospectively documented PMS and 36 controls were evaluated. Serum progesterone and allopregnanolone levels were measured on days 19 and 26 of the cycle as determined by urinary LH detection kits. Analysis of variance and Student t tests were used to analyze the data.

RESULTS

Allopregnanolone levels were significantly lower on day 26 in the PMS group than in controls (3.6 +/- 0.8 versus 7.5 +/- 1.3 ng/mL; P < .04). Significant differences in the ratio of the metabolite to progesterone also were noted, with a smaller ratio in the PMS subjects (0.9 +/- 0.3 versus 3.2 +/- 1.3 ng/mL; P < .05). There were no significant differences between the PMS and control groups with respect to serum progesterone levels.

CONCLUSION

Subjects with PMS manifested lower levels of the anxiolytic metabolite allopregnanolone in the luteal phase when compared with controls. Diminished concentrations of allopregnanolone in women with PMS may lead to an inability to enhance gamma aminobutyric acid-mediated inhibition during states of altered central nervous system excitability, such as ovulation or physiologic or psychological stress. The lowered metabolite levels could contribute to the genesis of various mood symptoms of the disorder, such as anxiety, tension, and depression.