Anti-inflammatory effects of infliximab and methotrexate on peripheral blood and synovial fluid mononuclear cells: ex vivo study

OBJECTIVE

To investigate the effects of methotrexate (MTX) and the tumour necrosis factor inhibitor infliximab (IFX) on immune cells derived from peripheral blood mononuclear cells (PBMCs) and synovial fluid mononuclear cells (SFMCs) of inflammatory arthritis patients.

METHOD

Phytohaemagglutinin (PHA)-induced proliferation of healthy donors' PBMCs and synovial intermediate monocytes (CD14+CD16+ cells) in SFMCs derived from psoriatic arthritis (PsA) and rheumatoid arthritis (RA) patients was determined by flow cytometry following co-culture with IFX and MTX. PHA-induced interferon-γ (IFN-γ) production in PBMCs was measured by enzyme-linked immunosorbent assay. The drugs' effect on mRNA expression in SFMCs was determined by quantitative polymerase chain reaction.

RESULTS

The combination of IFX 10 μg/mL + MTX 0.1 μg/mL had the strongest inhibitory effect on PBMC proliferation (91%), followed by MTX 0.1 μg/mL (86%) and IFX 10 μg/mL (49%). In PHA-stimulated PBMCs, IFN-γ production was reduced by IFX 10 μg/mL, MTX 0.1 μg/mL, and IFX 10 μg/mL + MTX 0.1 μg/mL by 68%, 90%, and 85%, respectively. In SFMCs, IFX 10 µg/mL significantly reduced CD14+CD16+ cells compared to medium (PsA 54%, p < 0.01; RA 46%, p < 0.05), while MTX had no effect on this population. IFX + MTX led to a similar suppression of CD14+CD16+ cells as achieved by IFX alone. The drugs had different impacts on SFMC gene expression.

CONCLUSION

Both IFX and MTX effectively inhibited PBMC proliferation and IFN-γ production, but only IFX reduced synovial monocytes and pro-inflammatory gene expression in SFMCs, suggesting a differential impact of IFX and MTX on critical inflammatory cell populations ex vivo.

Measuring Psoriasis Severity at Home

Psoriasis plaque severity metrics, such as induration (thickness), erythema (redness), and desquamation (scaliness), are associated with the subsequent development of psoriatic arthritis (PsA) among cutaneous-only psoriasis patients (patients with skin or nail psoriasis but no psoriatic arthritis). These metrics can be used for PsA screening. However, a key challenge in PsA screening is to optimize accessibility and minimize costs for patients, while also reducing the burden on healthcare systems. Therefore, an ideal screening tool consists of questions that patients can answer without a physician's assistance. Although reference images can be used to help a patient self-assess erythema and desquamation severity, a patient would need a tactile induration reference card to self-assess induration severity. This protocol describes how to create an induration reference card, the Psoriasis Thickness Reference Card, as well as how to use it to assess lesion induration severity. Administration of reference images for erythema and desquamation and a Psoriasis Thickness Reference Card for induration to 27 psoriasis patients showed that patients were moderately successful at self-assessing the severity of these three metrics. These findings support the feasibility of a future PsA screening test that patients can complete without the need for physician assistance.

IL-23 induces CLEC5A+ IL-17A+ neutrophils and elicit skin inflammation associated with psoriatic arthritis

IL-23-activation of IL-17 producing T cells is involved in many rheumatic diseases. Herein, we investigate the role of IL-23 in the activation of myeloid cell subsets that contribute to skin inflammation in mice and man. IL-23 gene transfer in WT, IL-23RGFP reporter mice and subsequent analysis with spectral cytometry show that IL-23 regulates early innate immune events by inducing the expansion of a myeloid MDL1+CD11b+Ly6G+ population that dictates epidermal hyperplasia, acanthosis, and parakeratosis; hallmark pathologic features of psoriasis. Genetic ablation of MDL-1, a major PU.1 transcriptional target during myeloid differentiation exclusively expressed in myeloid cells, completely prevents IL-23-pathology. Moreover, we show that IL-23-induced myeloid subsets are also capable of producing IL-17A and IL-23R+MDL1+ cells are present in the involved skin of psoriasis patients and gene expression correlations between IL-23 and MDL-1 have been validated in multiple patient cohorts. Collectively, our data demonstrate a novel role of IL-23 in MDL-1-myelopoiesis that is responsible for skin inflammation and related pathologies. Our data open a new avenue of investigations regarding the role of IL-23 in the activation of myeloid immunoreceptors and their role in autoimmunity.

Nod-like receptors in inflammatory arthritis

Nod-like receptors (NLRs) are innate immune receptors that play a key role in sensing components from pathogens and from damaged cells or organelles. NLRs form signaling complexes that can lead to activation of transcription factors or effector caspases - by means of inflammasome activation -Inflammatory arthritis (IA) culminating in promoting inflammation. An increasing body of research supports the role of NLRs in driving pathogenesis of IA, a collection of diseases that include rheumatoid arthritis (RA), psoriatic arthritis (PsA), ankylosing spondylitis, and pediatric arthritis. In this review, we briefly discuss the main drivers of IA diseases and dive into the evidence for - and against - various NLRs in driving these diseases. We also review the studies examining the use of NLR and inflammasome inhibitors as potential therapies for IA.

Differences in transcriptional changes in psoriasis and psoriatic arthritis skin with immunoglobulin gene enrichment in psoriatic arthritis

OBJECTIVES

Approximately 20% of people with psoriasis develop PsA. Although genetic, clinical and environmental risk factors have been identified, it is not known why some people with psoriasis develop PsA. The skin disease is traditionally considered the same in both. This study compares transcriptional changes in psoriasis and PsA skin for the first time.

METHODS

Skin biopsies were collected from healthy controls (HC), and uninvolved and lesional skin from patients with PsA. Bulk tissue sequencing was performed and analysed using the pipeline Searchlight 2.0. Transcriptional changes in PsA skin were compared with existing sequencing data from participants with psoriasis without PsA (GSE121212). Psoriasis and PsA datasets could not be directly compared as different analysis methods were used. Data from participants with PsA in the GSE121212 dataset were used for validation.

RESULTS

Skin samples from 9 participants with PsA and 9 HC were sequenced, analysed and compared with available transcriptomic data for 16 participants with psoriasis compared with 16 HC. Uninvolved skin in psoriasis shared transcriptional changes with lesional skin in psoriasis, but uninvolved skin in PsA did not. Most transcriptional changes in psoriasis and PsA lesional skin were shared, but immunoglobulin genes were upregulated in PsA lesional skin specifically. The transcription factor POU2F1, which regulates immunoglobulin gene expression, was enriched in PsA lesional skin. This was confirmed in the validation cohort.

CONCLUSIONS

Immunoglobulin genes are upregulated in PsA but not in psoriasis skin lesions. This may have implications for the spread from the cutaneous compartment to other tissues.

Achilles tendon and enthesis assessment using ultrashort echo time magnetic resonance imaging (UTE-MRI) T1 and magnetization transfer (MT) modeling in psoriatic arthritis

The purpose of this study is to investigate the use of ultrashort echo time (UTE) magnetic resonance imaging (MRI) techniques (T1 and magnetization transfer [MT] modeling) for imaging of the Achilles tendons and entheses in patients with psoriatic arthritis (PsA) compared with asymptomatic volunteers. The heels of twenty-six PsA patients (age 59 ± 15 years, 41% female) and twenty-seven asymptomatic volunteers (age 33 ± 11 years, 47% female) were scanned in the sagittal plane with UTE-T1 and UTE-MT modeling sequences on a 3-T clinical scanner. UTE-T1 and macromolecular proton fraction (MMF; the main outcome of MT modeling) were calculated in the tensile portions of the Achilles tendon and at the enthesis (close to the calcaneus bone). Mann-Whitney-U tests were used to examine statistically significant differences between the two cohorts. UTE-T1 in the entheses was significantly higher for the PsA group compared with the asymptomatic group (967 ± 145 vs. 872 ± 133 ms, p < 0.01). UTE-T1 in the tendons was also significantly higher for the PsA group (950 ± 145 vs. 850 ± 138 ms, p < 0.01). MMF in the entheses was significantly lower in the PsA group compared with the asymptomatic group (15% ± 3% vs. 18% ± 3%, p < 0.01). MMF in the tendons was also significantly lower in the PsA group compared with the asymptomatic group (17% ± 4% vs. 20% ± 5%, p < 0.01). Percentage differences in MMF between the asymptomatic and PsA groups (-16.6% and -15.0% for the enthesis and tendon, respectively) were higher than the T1 differences (10.8% and 11.7% for the enthesis and tendon, respectively). The results suggest higher T1 and lower MMF in the Achilles tendons and entheses in PsA patients compared with the asymptomatic group. This study highlights the potential of UTE-T1 and UTE-MT modeling for quantitative evaluation of entheses and tendons in PsA patients.

Type-I interferon pathway and DNA damage accumulation in peripheral blood of patients with psoriatic arthritis

Objectives

The abnormal DNA damage response is associated with upregulation of the type-1 interferon (IFN-I) pathway in certain rheumatic diseases. We investigated whether such aberrant mechanisms operate in psoriatic arthritis (PsA).

Methods

DNA damage levels were measured by alkaline comet assay in peripheral blood mononuclear cells from 52 PsA patients and age-sex-matched healthy individuals. RNA expression of IFIT1, MX1 and IFI44, which are selectively induced by IFN-I, was quantitated by real-time polymerase chain reaction and their composite normalized expression resulted in IFN-I score calculation. RNA expression of IL1β, IL6, TNF, IL17A and IL23A was also assessed in PsA and control subgroups.

Results

In PsA, DNA damage accumulation was increased by almost two-fold compared to healthy individuals (olive tail moment arbitrary units, mean ± SD; 9.42 ± 2.71 vs 4.88 ± 1.98, p<0.0001). DNA damage levels significantly correlated with serum C-Reactive-protein and IL6 RNA expression in PBMCs. Despite increased DNA damage, the IFN-I score was strikingly lower in PsA patients compared to controls (-0.49 ± 6.99 vs 4.24 ± 4.26; p<0.0001). No correlation was found between IFN-I pathway downregulation and DNA damage. However, the IFN-I score in a PsA subgroup was lower in those patients with higher IL1β expression, as well as in those with higher TNF/IL23A PBMCs expression.

Conclusion

DNA damage in PsA correlates with measures of inflammation but is not associated with the IFN-I pathway induction. The unexpected IFN-I downregulation, albeit reminiscent to findings in experimental models of spondyloarthritis, may be implicated in PsA pathogenesis and explained by operation of other cytokines.

Optimising psoriatic arthritis therapy with immunological methods to increase standard evaluation: the protocol of an open-label multicentre, parallel-group, two-arm randomised controlled study evaluation precision medicine approach in the treatment of psoriatic arthritis

INTRODUCTION

Psoriatic arthritis (PsA) affects around 150 000 people in the UK of whom around 50% require treatment with biologics. The most used biologics for PsA target tumour necrosis factor (TNF) or interleukin-17A (IL-17A). About 50% of patients respond to each, but it is not currently possible to predict response for individual patients, necessitating sequential treatment steps. A recent proof of concept study in PsA suggested that using peripheral immunophenotype to choose therapy could improve time to treatment response.This study will test the hypothesis, within an open-label parallel-group biomarker-stratified multicentre randomised controlled trial, which the baseline proportion of CD4+T cells with an activated type 17 immunophenotype (Th17 levels) predicts response to IL-17A or TNF inhibitors in PsA. Additional analyses will identify if the model can be refined by combining additional clinical and immunophenotypic factors. Statistical modelling will be used to predict the likely effectiveness of these approaches compared with standard care.

METHODS AND ANALYSIS

Patients with PsA eligible to start their first biologic as part of standard care are recruited and baseline blood tests are taken for immunophenotyping. Participants are stratified equally by Th17 levels and randomised 1:1 to receive either TNF (adalimumab) or IL-17A (secukinumab) inhibitors. The primary analysis will establish the interaction between baseline immunophenotype and treatment on the primary outcome (achievement of minimal disease activity criteria at week 24). In secondary analysis, modelling will identify if this prediction model can be optimised further by incorporating clinical phenotypes and additional immunophenotyping techniques.

ETHICS AND DISSEMINATION

Ethical approval for the study was granted by the North West Preston Research Ethics Committee (ref 21/NW/0016). Dissemination will be via conference presentations and peer-reviewed publications, aiming to impact on treatment guidelines.

TRIAL REGISTRATION NUMBER

ISRCTN17228602.

Value of Hands Ultrasonography in the Differential Diagnosis Between Psoriatic Arthritis and Rheumatoid Arthritis

OBJECTIVES

Psoriatic arthritis (PsA) can mimic rheumatoid arthritis (RA) at an early stage, especially when psoriasis is lacking. In the absence of specific radiological and immunological markers, the differential diagnosis between these two diseases can be challenging. We aimed to determine whether hands ultrasonography (US) may be useful in the differential diagnosis between PsA and RA.

METHODS

We conducted a cross-sectional study including patients with PsA and RA. All wrists and small joints of the hands were examined using gray-scale and Power Doppler US. The evaluated US lesions were: synovitis, tenosynovitis of extensor carpi ulnaris, extensor communis and flexor tendons, enthesitis of extensor tendons at distal interphalangeal joints, peritendon inflammation of extensor tendons, and soft tissue edema.

RESULTS

Six hundred joints in 20 PsA patients and 900 joints in 30 RA patients were assessed. Extensor enthesitis was significantly more observed in PsA compared with RA (39.4 vs 26.3%, P = .006) with a significant higher frequency of enthesophytes and calcifications (P = .022 and P = .002, respectively). Peritendon inflammation of extensor digitorum tendons was observed in 13% of metacarpophalangeal joints in PsA patients versus 3% in RA patients with a significant difference (P < .001). Soft tissue edema was exclusively observed in PsA (1.5 vs 0%, P = .033). Power Doppler synovitis was significantly more frequent in RA (9.2 vs 5%, P = .002). Extensor carpi ulnaris tenosynovitis was significantly more frequent in RA (18.3 vs 2.5%, P = .017).

CONCLUSION

Extrasynovial US findings may be helpful to distinguish PsA from RA especially in patients with immunonegative polyarthritis and no evidence of psoriasis.

Investigational monoclonal antibodies in early development for psoriatic arthritis: beyond the biosimilars

INTRODUCTION

Psoriatic Arthritis (PsA) is an inflammatory arthritis that is present in approximately 25% of psoriasis patients. Currently, several targeted therapies are available to manage PsA; however, many patients fail these therapies. Several new therapeutic options, with differing mechanisms of action, are currently being evaluated.

AREAS COVERED

This article reviews available results from phase I to phase III trials of several investigational monoclonal antibodies that the FDA has not yet approved for PsA. The proposed mechanisms of the new therapeutic agents and their relevance to the pathogenesis of PsA will be discussed. The investigational agents' efficacy and safety will be summarized, and their potential clinical applications for managing PsA will be contemplated.

EXPERT OPINION

Due to recent advances in understanding psoriatic arthritis, therapeutic agents are increasingly focused on inhibiting interleukin-17 and interleukin-23 pathways. Various strategies have been used to inhibit these cytokines, demonstrating favorable efficacy and acceptable safety profile.

DeepNAPSI multi-reader nail psoriasis prediction using deep learning

Nail psoriasis occurs in about every second psoriasis patient. Both, finger and toe nails can be affected and also severely destroyed. Furthermore, nail psoriasis is associated with a more severe course of the disease and the development of psoriatic arthritis. User independent quantification of nail psoriasis, however, is challenging due to the heterogeneous involvement of matrix and nail bed. For this purpose, the nail psoriasis severity index (NAPSI) has been developed. Experts grade pathological changes of each nail of the patient leading to a maximum score of 80 for all nails of the hands. Application in clinical practice, however, is not feasible due to the time-intensive manual grading process especially if more nails are involved. In this work we aimed to automatically quantify the modified NAPSI (mNAPSI) of patients using neuronal networks retrospectively. First, we performed photographs of the hands of patients with psoriasis, psoriatic arthritis, and rheumatoid arthritis. In a second step, we collected and annotated the mNAPSI scores of 1154 nail photos. Followingly, we extracted each nail automatically using an automatic key-point-detection system. The agreement among the three readers with a Cronbach's alpha of 94% was very high. With the nail images individually available, we trained a transformer-based neural network (BEiT) to predict the mNAPSI score. The network reached a good performance with an area-under-receiver-operator-curve of 88% and an area-under precision-recall-curve (PR-AUC) of 63%. We could compare the results with the human annotations and achieved a very high positive Pearson correlation of 90% by aggregating the predictions of the network on the test set to the patient-level. Lastly, we provided open access to the whole system enabling the use of the mNAPSI in clinical practice.

What happens under the flexor tendons of the fingers in dactylitis?

AIM

Tenosynovitis is one of the most frequently described inflammatory lesions in psoriatic dactylitis. The aim of the study was to assess by ultrasound the distribution of content within the synovial sheath of the finger flexor tendons in a cadaveric experimental model of tenosynovitis and to describe anatomically the elements of the space between the flexor tendons and the palmar aspect of the proximal phalanx of the fingers.

MATERIAL AND METHOD

Silicone was injected under ultrasound guidance into the digital flexor sheath of the index finger of a hand specimen. Ultrasound images of the distribution of the filling of the flexor synovial space with the injected material were obtained. These images were compared with images from patients with psoriatic dactylitis. The palmar regions of the hand and fingers were dissected to check the distribution of the injected silicone in the synovial cavity. Additionally, we dissected the 2nd to 5th fingers of five cadaveric hands, including the one used for the experiment.

RESULTS

During the injection of the substance, we observed an increasing homogeneous hypoechoic band around the flexor tendons that differed from the images of patients. Dissection of the specimen showed the injected silicone distributed throughout the digital flexor sheath to the distal interphalangeal joint. In addition, we provided an illustrated anatomical description of the elements located between the flexor tendons and the palmar aspect of the proximal phalanx, the inflammation of which could simulate flexor tenosynovitis.

CONCLUSION

The observations of this study may contribute to a better understanding of the anatomical structures involved in PsA dactylitis.

Effects of COVID-19 vaccination on disease activity in patients with rheumatoid arthritis and psoriatic arthritis on targeted therapy in the COVIDSER study

OBJECTIVE

To investigate the influence of COVID-19 vaccination on disease activity in rheumatoid arthritis (RA) and psoriatic arthritis (PsA) patients under targeted therapies.

PATIENTS AND METHODS

1765 vaccinated patients COVID-19, 1178 (66.7%) with RA and 587 (33.3%) with PsA from the COVID-19 registry in patients with rheumatic diseases (COVIDSER) project, were included. Demographics, disease characteristics, Disease Activity Score in 28 joints (DAS28) and targeted treatments were collected. DAS28-based flare rates and categorised disease activity distribution prevaccination and post vaccination were analysed by log-linear regression and contingency analyses, respectively. The influence of vaccination on DAS28 variation as a continuous measure was evaluated using a random coefficient model.

RESULTS

The distribution of categorised disease activity and flare rates was not significantly modified by vaccination. Log-linear regression showed no significant changes in the rate of flares in the 6-month period after vaccination compared with the same period prior to vaccination in neither patients with RA nor patients with PsA. When DAS28 variations were analysed using random coefficient models, no significant variations in disease activity were detected after vaccination for both groups of patients. However, patients with RA treated with Janus kinase inhibitors (JAK-i) (1) and interleukin-6 inhibitor (IL-6-i) experienced a worsening of disease activity (1.436±0.531, p=0.007, and 1.201±0.550, p=0.029, respectively) in comparison with those treated with tumour necrosis factor inhibitor (TNF-i). Similarly, patients with PsA treated with interleukin-12/23 inhibitor (IL-12/23-i) showed a worsening of disease activity (4.476±1.906, p=0.019) compared with those treated with TNF-i.

CONCLUSION

COVID-19 vaccination was not associated with increased rate of flares in patients with RA and PsA. However, a potential increase in disease activity in patients with RA treated with JAK-i and IL-6-i and in patients with PsA treated with IL-12/23-i warrants further investigation.

Psoriatic arthritis: Ultrasound peculiarities with particular emphasis on enthesitis

The prevalence of psoriatic arthritis among patients with psoriasis has a marked variability with ethnic and geographic variations. Inflammatory changes associated with psoriatic arthritis include bone erosion, tenosynovitis, and synovial hypertrophy, but enthesitis is considered the hallmark. Both X-ray and magnetic resonance imaging (MRI) are usefull in the diagnosis of psoriatic arthritis, but ultrasonography is the best imaging modality to assess entheses. Ultrasound findings of enthesitis include a loss of the regular fibrillar architecture, hypoechoic thickening, hypervascularization of tendons, ligaments, and joint capsules at their bony attachment, bony changes (including irregularities and erosions). Ultrasound has also proved the ability to detect inflammatory subclinical findings and to be useful in the follow-up of therapies.

Focal Synovial Inflammation Versus Enthesitis Theory in Distal Psoriatic Arthritis: A Pioneer Histopathologic Study

ABSTRACT

The aim of this analysis was to re-examine the classical concept of distal interphalangeal joint (DIP) psoriatic arthritis (PsA) as an entheseal-driven disease. Two cadaveric fingers with severe psoriatic arthritis were analyzed. Our results demonstrate that inflammation of DIP PsA is multifocal without interconnection between entheses and articular cartilage of the DIP. We found a clear association between synovitis and focal loss of articular cartilage at the head of the intermediate phalanx. By contrast, the articular cartilage adjacent to the zone of severe enthesitis did not show notable damage. Fibrocartilaginous destructions of enthesis were characterized by either a multifocal lymphocytic inflammation, accompanied by osteoclastic resorption, beginning on the interface between the uncalcified and calcified fibrocartilage and then extending into the bone or a subchondral bone inflammation which insidiously destroyed first the bone and then the fibrocartilage. Some sections well showed an inflammation either mild or prominent starting at the level of vascular foramina of flexor enthesis, with secondary invading into the interface between bone and enthesis. The different anatomic sites examined showed a slight predominance of CD8+ T cells over CD4+ T cells: 52% up to 63% for CD8+ T cells vs. to 36% up to 48% for CD4+ T cells. Sparse interspersed CD1a+cells and PS100+cells were also seen with a predominance of PS100+ cells on CD1a+ cells. CD20+ B cells, plasmocytes, neutrophils, and mastocytes were absent or rare. CD123 positive cells were not observed. In DIP PsA, 3 findings predominate: (1) cartilage invasion by the thin pannus offers a more rational explanation for the focal joint destruction than does inflammation of the enthesis which is independent from articular cartilage, (2) the thick ventral plate and to a lesser extend the thin dorsal plate constitute a barrier between the inflamed entheses and the articular cartilage, and (3) an unusual form of minute vascular foramen contributes to the early stage of enthesitis. This small study suggests that DIP PsA is a complex disease. It affects anatomical micro sites which, although close, are in fact relatively independent of each other. Further studies are needed to test this hypothesis.

Genetic Variants of the NF-κB Pathway: Unraveling the Genetic Architecture of Psoriatic Disease

Psoriasis is a multifactorial genetic disease for which the genetic factors explain about 70% of disease susceptibility. Up to 30–40% of psoriasis patients develop psoriatic arthritis (PsA). However, PsA can be considered as a “disease within a disease”, since in most cases psoriasis is already present when joint complaints begin. This has made studies that attempt to unravel the genetic basis for both components of psoriatic disease enormously difficult. Psoriatic disease is also accompanied by a high burden of comorbid conditions, mainly of the cardiometabolic type. It is currently unclear whether these comorbidities and psoriatic disease have a shared genetic basis or not. The nuclear factor of kappa light chain enhancer of activated B cells (NF-κB) is a transcription factor that regulates a plethora of genes in response to infection, inflammation, and a wide variety of stimuli on several cell types. This mini-review is focused on recent findings that highlight the importance of this pathway both in the susceptibility and in the determinism of some features of psoriatic disease. We also briefly review the importance of genetic variants of this pathway as biomarkers of pharmacological response. All the above may help to better understand the etiopathogenesis of this complex entity.

Tissue-Resident Memory CD8+ T Cells From Skin Differentiate Psoriatic Arthritis From Psoriasis

OBJECTIVE

To compare immune cell phenotype and function in psoriatic arthritis (PsA) versus psoriasis in order to better understand the pathogenesis of PsA.

METHODS

In-depth immunophenotyping of different T cell and dendritic cell subsets was performed in patients with PsA, psoriasis, or axial spondyloarthritis and healthy controls. Subsequently, we analyzed cells from peripheral blood, synovial fluid (SF), and skin biopsy specimens using flow cytometry, along with high-throughput transcriptome analyses and functional assays on the specific cell populations that appeared to differentiate PsA from psoriasis.

RESULTS

Compared to healthy controls, the peripheral blood of patients with PsA was characterized by an increase in regulatory CD4+ T cells and interleukin-17A (IL-17A) and IL-22 coproducing CD8+ T cells. One population specifically differentiated PsA from psoriasis: i.e., CD8+CCR10+ T cells were enriched in PsA. CD8+CCR10+ T cells expressed high levels of DNAX accessory molecule 1 and were effector memory cells that coexpressed skin-homing receptors CCR4 and cutaneous lymphocyte antigen. CD8+CCR10+ T cells were detected under inflammatory and homeostatic conditions in skin, but were not enriched in SF. Gene profiling further revealed that CD8+CCR10+ T cells expressed GATA3, FOXP3, and core transcriptional signature of tissue-resident memory T cells, including CD103. Specific genes, including RORC, IFNAR1, and ERAP1, were up-regulated in PsA compared to psoriasis. CD8+CCR10+ T cells were endowed with a Tc2/22-like cytokine profile, lacked cytotoxic potential, and displayed overall regulatory function.

CONCLUSION

Tissue-resident memory CD8+ T cells derived from the skin are enhanced in the circulation of patients with PsA compared to patients with psoriasis alone. This may indicate that aberrances in cutaneous tissue homeostasis contribute to arthritis development.

IL-23 skin and joint profiling in psoriatic arthritis: novel perspectives in understanding clinical responses to IL-23 inhibitors

OBJECTIVES

To determine the relationship between synovial versus skin transcriptional/histological profiles in patients with active psoriatic arthritis (PsA) and explore mechanistic links between diseased tissue pathology and clinical outcomes.

METHODS

Twenty-seven active PsA patients were enrolled in an observational/open-label study and underwent biopsies of synovium and paired lesional/non-lesional skin before starting anti-tumour necrosis factor (TNF) (if biologic-naïve) or ustekinumab (if anti-TNF inadequate responders). Molecular analysis of 80-inflammation-related genes and protein levels for interleukin (IL)-23p40/IL-23p19/IL-23R were assessed by real-time-PCR and immunohistochemistry, respectively.

RESULTS

At baseline, all patients had persistent active disease as per inclusion criteria. At primary end-point (16-weeks post-treatment), skin responses favoured ustekinumab, while joint responses favoured anti-TNF therapies. Principal component analysis revealed distinct clustering of synovial tissue gene expression away from the matched skin. While IL12B, IL23A and IL23R were homogeneously expressed in lesional skin, their expression was extremely heterogeneous in paired synovial tissues. Here, IL-23 transcriptomic/protein expression was strongly linked to patients with high-grade synovitis who, however, were not distinguishable by conventional clinimetric measures.

CONCLUSIONS

PsA synovial tissue shows a heterogeneous IL-23 axis profile when compared with matched skin. Synovial molecular pathology may help to identify among clinically indistinguishable patients those with a greater probability of responding to IL-23 inhibitors.

Do tender joints in active psoriatic arthritis reflect inflammation assessed by ultrasound and magnetic resonance imaging?

OBJECTIVE

To investigate the association between clinical joint tenderness and intra- and periarticular inflammation as assessed by ultrasound and magnetic resonance imaging (MRI) in patients with active psoriatic arthritis (PsA) and to explore if the associations differ according to patient-reported outcomes (PROs) and structural damage.

METHODS

Forty-one patients with active PsA and hand involvement had 76/78 joints examined for swelling/tenderness and ultrasound and MRI of 24 and 12 finger joints, respectively. Synovitis, tenosynovitis, periarticular inflammation and erosions were assessed using OMERACT definitions and scoring systems. Correlation between imaging inflammation sum-scores (intra-and periarticular) and tender/swollen joint counts were calculated using Spearman's rho, agreement at joint level was examined using prevalence and bias adjusted kappa (PABAK). Subgroup analyses explored the influence of PROs and radiographic erosive disease on these associations.

RESULTS

No significant correlations were found between tender or swollen joint counts and imaging inflammation sum-scores (rho=-0.31-0.38). In patients with higher level of overall pain, disability and lower self-reported mental health, a tendency towards negative correlations were found. At joint level, intra- and periarticular imaging inflammatory lesions had slight agreement with joint tenderness (PABAK=0.02-0.19) and slight to moderate with swelling (PABAK=0.16-0.54). For tender joints, agreement with imaging inflammation was even weaker in patients with either high overall pain scores, high disability scores, and/or non-erosive disease.

CONCLUSION

Joint tenderness had low association with imaging signs of inflammation in PsA patients, particularly in patients with high self-reported pain, disability and low mental health, indicating that tenderness is influenced by other parameters than local inflammation.

Psoriatic arthritis is associated with adverse body composition predictive of greater coronary heart disease and type 2 diabetes propensity - a cross-sectional study

OBJECTIVES

To compare body composition in PsA with metabolic disease free (MDF) controls and type 2 diabetes and assess body-composition predicted propensity for cardiometabolic disease.

METHODS

Detailed MRI body composition profiles of 26 PsA participants from the IMAPA study were compared with 130 age, sex and BMI-matched MDF controls and 454 individuals with type 2 diabetes from UK Biobank. The body-composition predicted propensity for coronary heart disease (CHD) and type 2 diabetes was compared between PsA and matched MDF controls.

RESULTS

PsA participants had a significantly greater visceral adipose tissue (VAT) volume [mean 5.89 l (s.d. 2.10 l)] compared with matched-MDF controls [mean 4.34 l (s.d. 1.83 l)] (P <0.001) and liver fat percentage [median 8.88% (interquartile range 4.42-13.18%)] compared with MDF controls [3.29% (1.98-7.25%)] (P <0.001). These differences remained significant after adjustment for age, sex and BMI. There were no statistically significant differences in VAT, liver fat or muscle fat infiltration (MFI) between PsA and type 2 diabetes. PsA participants had a lower thigh muscle volume than MDF controls and those with type 2 diabetes. Body composition-predicted propensity for CHD and type 2 diabetes was 1.27 and 1.83 times higher, respectively, for PsA compared with matched-MDF controls.

CONCLUSION

Individuals with PsA have an adverse body composition phenotype with greater visceral and ectopic liver fat and lower thigh muscle volume than matched MDF controls. Body fat distribution in PsA is more in keeping with the pattern observed in type 2 diabetes and is associated with greater propensity to cardiometabolic disease. These data support the need for greater emphasis on weight loss in PsA management to lessen CHD and type 2 diabetes risk.

Inhibition of Phosphodiesterase-4 in Psoriatic Arthritis and Inflammatory Bowel Diseases

Phosphodiesterases (PDEs) are a heterogeneous superfamily of enzymes which catalyze the degradation of the intracellular second messengers cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP). Among PDEs, PDE4 is the most widely studied and characterized isoenzyme. PDE4 blocking can lead to increased levels of intracellular cAMP, which results in down-regulation of inflammatory responses by reducing the expression of tumor necrosis factor (TNF), interleukin (IL)-23, IL-17, interferon-γ, while increasing regulatory cytokines, such as IL-10. Therefore, PDE4 has been explored as a therapeutic target for the treatment of different chronic inflammatory conditions such as psoriatic arthritis (PsA) and inflammatory bowel disease (IBD). PsA shares clinical, genetic, and pathogenic features with IBD such as ulcerative colitis (UC) and Crohn’s disease (CD), and enteropathic spondyloarthritis (eSpA) represent a frequent clinical evidence of the overlap between gut and joint diseases. Current therapeutic options in PsA patients and underlying UC are limited to synthetic immunosuppressants and anti-TNF. Apremilast is an oral PDE4 inhibitor approved for the treatment of active PsA patients with inadequate response to synthetic immunosuppressants. The efficacy and a good safety profile observed in randomized clinical trials with apremilast in PsA patients have been confirmed by few studies in a real-life scenario. In addition, apremilast led to significant improvement in clinical and endoscopic features in UC patients in a phase II RCT. By now there are no available data regarding its role in eSpA patients. In view of the above, the use of apremilast in eSpA patients is a route that deserves to be deepened.

Differential Requirement for CCR6 in IL-23-Mediated Skin and Joint Inflammation

CCR6 is important for the trafficking of IL-17A-producing γδ T cells and required for the development of psoriasiform dermatitis in an IL-23 intradermal injection model. The role of CCR6, however, in IL-23-mediated joint inflammation is unclear. We herein hydrodynamically delivered IL-23 minicircle DNA into wild-type and CCR6-deficient (CCR6-knockout) mice to induce overexpression of IL-23 systemically. After IL-23 gene transfer, wild-type mice exhibited concurrent skin and joint changes that recapitulate some features found in human psoriatic skin and joints. CCR6-knockout mice were resistant to IL-23-induced skin inflammation but exhibited no changes in joint inflammation compared with wild-type mice. Depletion of neutrophils protected wild-type mice from skin and joint disease without suppressing T helper type 17 cytokine expression. In contrast, mice lacking γδ T cells showed a partial reduction in neutrophilic recruitment and a significant decrease in IL-17A expression in skin and paw tissue. Thus, in an IL-23-mediated model that allows concurrent assessment of both skin and joint disease, we showed that CCR6 is critical for inflammation in the skin but not in the joint. Furthermore, our data suggest that neutrophils and γδ T cells are key effector cells in IL-23-mediated skin and joint inflammation in mice.

Understanding the Pathogenesis of Spondyloarthritis

Spondyloarthritis comprises a group of inflammatory diseases of the joints and spine, with various clinical manifestations. The group includes ankylosing spondylitis, reactive arthritis, psoriatic arthritis, arthritis associated with inflammatory bowel disease, and undifferentiated spondyloarthritis. The exact etiology and pathogenesis of spondyloarthritis are still unknown, but five hypotheses explaining the pathogenesis exist. These hypotheses suggest that spondyloarthritis is caused by arthritogenic peptides, an unfolded protein response, HLA-B*27 homodimer formation, malfunctioning endoplasmic reticulum aminopeptidases, and, last but not least, gut inflammation and dysbiosis. Here we discuss the five hypotheses and the evidence supporting each. In all of these hypotheses, HLA-B*27 plays a central role. It is likely that a combination of these hypotheses, with HLA-B*27 taking center stage, will eventually explain the development of spondyloarthritis in predisposed individuals.

Risk for development of inflammatory bowel disease under inhibition of interleukin 17: A systematic review and meta-analysis

Objective

Cases of inflammatory bowel disease (IBD) during treatment with interleukin (IL)-17 antagonists have been reported from trials in psoriasis, psoriatic arthritis, and ankylosing spondylitis. The aim of this study was to assess the overall risk for development of IBD due to IL-17 inhibition.

Design

Systematic review and meta-analysis of studies conducted 2010–2018 of treatment with IL-17 antagonists in patients with psoriasis, psoriatic arthritis, ankylosing spondylitis, and rheumatoid arthritis. We compared risk of IBD development in anti-IL-17 treated patients compared to placebo treatments. We also computed incident rates of IBD overall. A ‘worst case scenario’ defining subjects ambiguous for prevalent versus incident cases for the latter was also applied.

Results

Sixty-six studies of 14,390 patients exposed to induction and 19,380 patients exposed to induction and/or maintenance treatment were included. During induction, 11 incident cases of IBD were reported, whereas 33 cases were diagnosed during the entire treatment period. There was no difference in the pooled risk of new-onset IBD during induction studies for both the best-case [risk difference (RD) 0.0001 (95% CI: -0.0011, 0.0013)] and worst-case scenario [RD 0.0008 (95% CI: -0.0005, 0.0022)]. The risk of IBD was not different from placebo when including data from maintenance and long-term extension studies [RD 0.0007 (95% CI: -0.0023, 0.0036) and RD 0.0022 (95% CI: -0.0010, 0.0055), respectively].

Conclusions

The risk for development of IBD in patients treated with IL-17 antagonists is not elevated. Prospective surveillance of patients treated with IL-17 antagonists with symptom and biomarker assessments is warranted to assess for onset of IBD in these patients.

Assessment of the many faces of PsA: single and composite measures in PsA clinical trials

PsA is a complex, heterogeneous disease that can place a large burden on patients' psychological and physical well-being. The multifaceted nature of PsA poses a significant assessment challenge, both in randomized control trials and in clinical practice. In recent years, there has been much progress in the development of unidimensional and composite measures of disease activity, as well as of questionnaires that capture the patient's perspective of the condition. Despite these advances, there remains uncertainty around which tools to implement within a research setting. This review aims to summarize the currently available clinical and patient-derived assessment tools, providing a practical and informative resource for the assessment of PsA. This review will also explore recent advancements in digital approaches to the assessment of rheumatological conditions. This will highlight the potential for digitalization in the assessment and monitoring of PsA, outlining innovative means of capturing disease activity and treatment response.

Promotion of macrophage activation by Tie2 in the context of the inflamed synovia of rheumatoid arthritis and psoriatic arthritis patients

OBJECTIVE

To examine the role of Tie2 signalling in macrophage activation within the context of the inflammatory synovial microenvironment present in patients with RA and PsA.

METHODS

Clinical responses and macrophage function were examined in wild-type and Tie2-overexpressing (Tie2-TG) mice in the K/BxN serum transfer model of arthritis. Macrophages derived from peripheral blood monocytes from healthy donors, RA and PsA patients, and RA and PsA synovial tissue explants were stimulated with TNF (10 ng/ml), angiopoietin (Ang)-1 or Ang-2 (200 ng/ml), or incubated with an anti-Ang2 neutralizing antibody. mRNA and protein expression of inflammatory mediators was analysed by quantitative PCR, ELISA and Luminex.

RESULTS

Tie2-TG mice displayed more clinically severe arthritis than wild-type mice, accompanied by enhanced joint expression of IL6, IL12B, NOS2, CCL2 and CXCL10, and activation of bone marrow-derived macrophages in response to Ang-2 stimulation. Ang-1 and Ang-2 significantly enhanced TNF-induced expression of pro-inflammatory cytokines and chemokines in macrophages from healthy donors differentiated with RA and PsA SF and peripheral blood-derived macrophages from RA and PsA patients. Both Ang-1 and Ang-2 induced the production of IL-6, IL-12p40, IL-8 and CCL-3 in synovial tissue explants of RA and PsA patients, and Ang-2 neutralization suppressed the production of IL-6 and IL-8 in the synovial tissue of RA patients.

CONCLUSION

Tie2 signalling enhances TNF-dependent activation of macrophages within the context of ongoing synovial inflammation in RA and PsA, and neutralization of Tie2 ligands might be a promising therapeutic target in the treatment of these diseases.

Psoriatic and psoriatic arthritis patients with and without jet-lag: does it matter for disease severity scores? Insights and implications from a pilot, prospective study

Background: Jet-lag may affect air-travelers crossing at least two time-zones and has several health-care implications. It occurs when the human biological rhythms are out of synch with respect to the day-night cycle at the country destination. Its effect in psoriasis is missing. We aimed to evaluate the effect of Jet-lag in psoriatic patients' management. Methods: This is a prospective observational study that enrolled psoriatic patients that underwent a flight: patients who experienced jet-lag were compared to patients who did not experience jet-lag. Before the flight, a dermatologist recorded clinical and demographical data with particular attention to Psoriasis Area Severity Index (PASI) and Disease Activity in Psoriatic Arthritis (DAPSA). Patients performed Self-Administered Psoriasis Area Severity Index (SAPASI), the Dermatology Life Quality Index (DLQI) and the pruritus Visual Analog Scale (VAS) scores. After the flight, patients completed the SAPASI, DLQI and pruritus-VAS scores. Results: The sample recruited comprised of 70 psoriatic patients aged 42.4 ± 9.7 years (median 42.5 years). Thirty (42.9%) were males, mean BMI was 25.5 ± 2.2 kg/m2. Average disease duration was 15.2 ± 7.1 years, and 20 (28.6%) subjects had developed PsA. Average hours of flight were 5.4 ± 3.5 (median 3.5 h), with 34 (48.6%) subjects reporting jet-lag. At the multivariate regression analysis, the change in the SAPASI score resulted correlated with jet-lag (regression coefficient 1.63, p = .0092), as well the change in the DLQI score (regression coefficient = 1.73, p = .0009), but no change on the pruritus VAS scale was found. Conclusions: The present study suggests that jet-lag may influence disease severity and DLQI scores, but not itch in psoriatic patients.

Differences in Osteoimmunological Biomarkers Predictive of Psoriatic Arthritis among a Large Italian Cohort of Psoriatic Patients

(1) Background: In literature it is reported that 20–30% of psoriatic patients evolve to psoriatic arthritis over time. Currently, no specific biochemical markers can either predict progression to psoriatic arthritis or response to therapies. This study aimed to identify osteoimmunological markers applicable to clinical practice, giving a quantitative tool for evaluating pathological status and, eventually, to provide prognostic support in diagnosis. (2) Methods: Soluble (serum) bone and cartilage markers were quantified in 50 patients with only psoriasis, 50 psoriatic patients with psoriatic arthritis, and 20 healthy controls by means of multiplex and enzyme-linked immunoassays. (3) Results: Differences in the concentrations of matrix metalloproteases (MMPs), tissue inhibitors of metalloproteinases (TIMPs), receptor activator of nuclear factor kappa-B- ligand (RANK-L), procollagen type I N propeptide (PINP), C-terminal telopeptide of type I collagen (CTx-I), dickkopf-related protein 1 (DKK1), and sclerostin (SOST) distinguished healthy controls from psoriasis and psoriatic arthritis patients. We found that MMP2, MMP12, MMP13, TIMP2, and TIMP4 distinguished psoriasis from psoriatic arthritis patients undergoing a systemic treatment, with a good diagnostic accuracy (Area under the ROC Curve (AUC) > 0.7). Then, chitinase-3-like protein 1 (CHI3L1) and MMP10 distinguished psoriasis from psoriatic arthritis not undergoing systemic therapy and, in the presence of onychopathy, MMP8 levels were higher in psoriasis than in psoriatic arthritis. However, in these latter cases, the diagnostic accuracy of the identified biomarkers was low (0.5 < AUC < 0.7). (4) Conclusions. By highlighting never exploited differences, the wide osteoimmunological biomarkers panel provides a novel clue to the development of diagnostic paths in psoriasis and psoriasis-associated arthropathic disease.

Adenoviral gene transfer of a single-chain IL-23 induces psoriatic arthritis-like symptoms in NOD mice

Previously, we demonstrated that intratumoral delivery of adenoviral vector encoding single-chain (sc)IL-23 (Ad.scIL-23) was able to induce systemic antitumor immunity. Here, we examined the role of IL-23 in diabetes in nonobese diabetic mice. Intravenous delivery of Ad.scIL-23 did not accelerate the onset of hyperglycemia but instead resulted in the development of psoriatic arthritis. Ad.scIL-23-treated mice developed erythema, scales, and thickening of the skin, as well as intervertebral disc degeneration and extensive synovial hypertrophy and loss of articular cartilage in the knees. Immunological analysis revealed activation of conventional T helper type 17 cells and IL-17-producing γδ T cells along with a significant depletion and suppression of T cells in the pancreatic lymph nodes. Furthermore, treatment with anti-IL-17 antibody reduced joint and skin psoriatic arthritis pathologies. Thus, these Ad.scIL-23-treated mice represent a physiologically relevant model of psoriatic arthritis for understanding disease progression and for testing therapeutic approaches.-Flores, R. R., Carbo, L., Kim, E., Van Meter, M., De Padilla, C. M. L., Zhao, J., Colangelo, D., Yousefzadeh, M. J., Angelini, L. A., Zhang, L., Pola, E., Vo, N., Evans, C. H., Gambotto, A., Niedernhofer, L. J., Robbins, P. D. Adenoviral gene transfer of a single-chain IL-23 induces psoriatic arthritis-like symptoms in NOD mice.

[PSORIATIC ARTHRITIS IN CHILDREN: CHARACTERISTICS OF THE CLINICAL PICTURE]

The aim of the study is to establish the features of the clinical course of psoriatic arthritis in children. 83 patients with psoriatic arthritis (PSA) were examined. The terms of formation of articular and skin syndromes in PSA in children, as well as options for the onset and height of the disease and features of the course in childhood were revealed. Based on the results of the study, it should be concluded that, in contrast to the literature data, the majority of patients with PSA disease debut falls on the age of 6.5 years, the disease begins with skin lesions and in the debut of the joint syndrome. 6-7 years later from the onset of the disease in patients have asymmetric oligoarthritis, spondylitis in combination with the lesion of peripheral joints, also revealed mutilatng arthritis, however, were the leaders of the symmetric rheumatoid option. It should be noted that all observed patients expressed periarticular osteoporosis, which is not typical for this pathology.

FEATURES OF MICROBIOTA IN PSORIATIC DISEASE: FROM SKIN AND GUT PERSPECTIVES (REVIEW)

Psoriatic disease is a chronic inflammatory disease characterized by skin lesions. Psoriasis development has been associated both with genetic and environmental factors. Though skin and gut microbiota has been implicated in number of pathologies including atopic dermatitis, inflammatory bowel disease, Crohn's disease, allergy, and obesity, its role has been poorly studied in psoriatic disease, which incorporates both psoriasis and psoriatic arthritis. This literature review summarizes the most recent and major findings on microbiota features in psoriatic disease. Despite conflicting findings, psoriasis patients were frequently found to have distinct microbial composition in both skin and guts especially in the major bacterial phyla, Firmicutes, Bacteroidetes, and genus Akkermansia. Furthermore, bacterial DNA has been found in psoriatic patients both locally and systemically, and altogether suggesting a crucial role of bacteria in psoriatic disease and future studies in this field.

IL-9 receptor: Regulatory role on FLS and pannus formation

OBJECTIVE

Functions of the Th9 cells and its signature cytokine IL-9 in human autoimmune diseases is currently under extensive research. Here we are reporting new functions of IL-9-receptor (IL-9R); its regulatory role on (i) FLS (fibroblast like synoviocyte) biology and (ii) pannus formation in rheumatoid arthritis (RA) and psoriatic arthritis (PsA).

METHODS

RA, PsA, and OA synovial tissue biopsies were obtained; FLS were derived and cultured from these tissues. T quantify protein and messenger RNA levels of IL9-receptor (IL-9R) Western blot and real-time PCR techniques were used. For Pro-growth/survival effect of IL-9 (rIL-9) Annexin-V (apoptosis assay) and MTT assays were used.

RESULTS

Immunoblot and RT-PCR studies demonstrated IL9-R in FLS of RA, PsA, and OA. IL9-R was functionally active. rIL-9 induced significant proliferation of FLS (p < 0.001) and had an inhibitory effect on TNF-α induced apoptosis. Proliferation of FLS induced by rIL-9 could be significantly inhibited (p < 0.001) with an IL-9R antibody. Further we observed, rIL-9 induced increased secretion of IL-6, IL-8 and also unregulated MMP-3 expression in FLS.

CONCLUSIONS

Proliferation of FLS, induction of pro-nflammatory cytokines and upregulation of metaloprotinase (MMP 3) the key pathologic events for pannus formation are regulated by IL-9 and its recptor. Thus the IL-9/IL-9R system is a new contributing factor in the cytokine network of PsA and RA.

Ten years of follow-up data in psoriatic arthritis: results based on standardized monitoring of patients in an ordinary outpatient clinic in southern Norway

BACKGROUND

Over the last decade, a treat-to-target (T2T) strategy has been recommended for psoriatic arthritis (PsA) and new treatment options have become available. There is a lack of data on PsA regarding any changes that may have occurred over these past years. Thus, the main aim of this study was to look for changes in clinical disease status and treatment in a PsA outpatient clinic population monitored over the period 2008 to 2017.

METHODS

Annual data collection included demographic data, laboratory (erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP)) and clinic measures of disease activity (e.g., 28 and 32 joint count Disease Activity Score (DAS28), Clinical Disease Activity Index (CDAI), and modified Disease Activity index for Psoriatic arthritis (DAPSA)), evaluator's global assessment, and patient-reported outcomes (PROs), including for example measures of physical function, pain, and patient global assessment. Disease-modifying antirheumatic drug (DMARD) use was also registered.

RESULTS

In the PsA outpatient clinic population over the 10-year period (annual mean number of patients, 331) the mean (standard deviation) age was 58.4 (12.4) years, disease duration was 9.6 (7.9) years, 49.4% were female, and 17.6% were current smokers. From 2008 to 2017, no statistically significant increase in remission rates was seen for DAPSA (13.5% and 22.0%) or Boolean remission (6.6% and 8.9%), whereas a statistically significant increase was seen for DAS28-ESR (36.8% and 50.6%) and CDAI (20.0% and 29.6%), but not for the last 5 years (DAS28-ESR, 42.3% and 50.6%; CDAI, 27.9% and 29.6%). Furthermore, over the 10-year period no significant improvement for PROs and no significant change in the use of synthetic (annual mean 53.0%) and biologic DMARDs (annual mean 29.9%) was found.

CONCLUSION

Our data suggest that even in the biologic treatment era there is an unmet need for treating PsA patients to target remission. New treatment options and the development of more feasible and valid outcome measures for use in a T2T strategy in ordinary clinical practice may in the future to further improve clinical outcomes in PsA.

Clinical and ultrasonographic predictors for achieving minimal disease activity in patients with psoriatic arthritis: the UPSTREAM (Ultrasound in PSoriatic arthritis TREAtMent) prospective observational study protocol

INTRODUCTION

Psoriatic arthritis (PsA) occurs in 10%-15% of people with psoriasis and accounts for 10%-20% of early arthritis clinics referral. Only a few prognostic factors of therapeutic response in patients with PsA have been identified. In the last years, the role of imaging has grown up and the European League Against Rheumatism recognised that ultrasound (US) has higher sensitivity than clinical examination to detect inflammatory disease activity. The aims of the Ultrasound in PSoriatic arthritis TREAtMent (UPSTREAM) study are to integrate clinic and US in order to inform whether US has provide an added prognostic value in PsA.

METHODS AND ANALYSIS

UPSTREAM is an observational prospective cohort study enrolling patients with PsA having clinically active joint disease and starting a new course of therapy. The primary objective is to evaluate the additional value of US over clinical examination in detecting patients achieving minimal disease activity after 6 months. Data will be obtained at baseline and at standard clinical follow-up visits. Patient's clinical assessment will be performed according to the core set proposed by the Group for Research and Assessment of Psoriasis and Psoriatic Arthritis-Outcome Measures in Rheumatology. Sonographic evaluations will be performed by expert sonographers in 42 joints, 36 tendons, 12 entheses and 2 bursae, according to a score that will be purposely developed for PsA by the US Study Group of the Italian Society for Rheumatology. The UPSTREAM study will identify clinical and US predictors of response to treatment in patients with PsA and active peripheral arthritis starting a new course of therapy.

ETHICS AND DISSEMINATION

Ethic approval for this study has been obtained from the institutional review board (IRB)/independent ethics committee (IEC) Comitato Etico Lazio 1 (Prot. N 198 02-02-2017) and then locally from the IRB/IEC of each participating centre. Results will be published in relevant scientific journals and be disseminated in international conferences. Fully anonymised data will be accessible from authors upon request.

TRIAL REGISTRATION NUMBER

NCT03330769; Pre-results.

The pathogenesis of psoriatic arthritis

Psoriatic arthritis is a chronic, immune-mediated, inflammatory arthropathy that presents with inflammation of the joints and entheses, including those of the axial skeleton, and is associated with increased mortality from cardiovascular disease. Diagnosis is primarily based on clinical phenotype because of the diversity of the associated features, which can include skin and nail disease, dactylitis, uveitis, and osteitis. Improved understanding of the pathogenesis of psoriatic arthritis has led to the development of effective biologics and small-molecular drugs targeting specific cytokines and signalling pathways, which can prevent disease progression and improve quality of life. However, at least 40% of patients with psoriatic arthritis have only a partial response or fail to respond to such treatments. Cytokine inhibitors, mainly those specific for tumour necrosis factor and, more recently, the interleukin 23-T-helper-17 cell pathway, have been highly successful in the treatment of disease manifestations in several different tissues, although targeting the interleukin 23-T-helper-17 cell pathway might be more effective in psoriasis than in arthritis. However, the precise mechanisms underlying the pathogenesis of psoriatic arthritis-which include genetics, environmental factors, and immune-mediated inflammation-are complex, and the relationship between disease of the joint and that of other domains is poorly understood. Improving our understanding of psoriatic arthritis pathogenesis could help to establish validated biomarkers for diagnosis, predict therapeutic response and remission, develop precision medicines, and predict which patients will respond to which therapy. We discuss advances in pathogenetic translational research that could inform these issues.

Report of the Skin Research Working Groups from the GRAPPA 2017 Annual Meeting

At the 2017 annual meeting of the Group for Research and Assessment of Psoriasis and Psoriatic Arthritis (GRAPPA), the International Dermatology Outcome Measures (IDEOM) psoriasis working group presented an overview of its cutaneous domain of psoriatic arthritis (PsA) projects. First, the group presented an overview of IDEOM's work to establish psoriasis outcome measures that satisfy the needs of all those involved. Second, the group discussed replacements for the Psoriasis Area and Severity Index (PASI) that can be used in clinical practice, including data that support the use of the physician's global assessment × body surface area measurement score as a PASI surrogate. Third, the group discussed the contribution of skin disease to composite measures of PsA. Last, the group summarized the National Psoriasis Foundation's efforts to establish treat-to-target strategies for psoriasis care.

Ultrasonography of the nail unit reveals quantitative and qualitative alterations in patients with psoriasis and psoriatic arthritis

AIMS

The nail unit is a matter of interest both for dermatologist and rheumatologist. The nail is considered one of the possible targets of assessment, especially when ultrasonography is performed. The aim of the study is to highlight peculiar features and alterations of the nail unit in patients affected by psoriasis and psoriatic arthritis versus healthy controls using ultrasonography.

MATERIALS AND METHODS

The study sample included 82 patients affected by psoriasis and/or psoriatic arthritis and 50 healthy controls. The patients were consecutively enrolled during their routine visit in the outpatient clinic and they performed clinical and ultrasonographic evaluation of the nail. The evaluationof disease activity was done using Disease Activity in Psoriatic Arthritis (DAPSA), Psoriasis Activity Severity Index (PASI), and Nail Psoriasi Severity Index (NAPSI).

RESULTS

Multivariate analysis of variance was performed between groups. Post hoc analysis underlined the differences between healthy and affected regarding nail plate thickness (0.063±0.011 cm for patients with psoriasis, 0.065±0.014 cm for patients with psoriatic arthritis and 0.051±0.006 cm for healthy controls, p<0.05). Elementary lesions of nail plate and nail bed were compared using Pearson's chi square test between patients in psoriasis and psoriatic arthritis groups, with no differences except for a trend for onycholisis and crumbling (p=0.07 and 0.06, respectively) in the psoriatic arthritis group. ROC curves were calculated (AUC = 0.68) obtaining also quantitative cut offs for nail plate andnail bed thickness in the affected vs healthy patients.

CONCLUSIONS

Our study shows that ultrasonography may be a potential advantage in clinical practice. Our results strengthen the information already available in the literature and add quantitative parameters for ultrasonography of the nail.

Mannan-induced Nos2 in macrophages enhances IL-17-driven psoriatic arthritis by innate lymphocytes

Previous identification of the inducible nitric oxide synthase (NOS2) gene as a risk allele for psoriasis (Ps) and psoriatic arthritis (PsA) suggests a possible pathogenic role of nitric oxide (NO). Using a mouse model of mannan-induced Ps and PsA (MIP), where macrophages play a regulatory role by releasing reactive oxygen species (ROS), we found that NO was detectable before disease onset in mice, independent of a functional nicotinamide adenine dinucleotide phosphate oxidase 2 complex. MIP was suppressed by either deletion of Nos2 or inhibition of NO synthases with NG-nitro-l-arginine methyl ester, demonstrating that Nos2-derived NO is pathogenic. NOS2 expression was also up-regulated in lipopolysaccharide- and interferon-γ-stimulated monocyte subsets from patients with PsA compared to healthy controls. Nos2-dependent interleukin-1α (IL-1α) release from skin macrophages was essential for arthritis development by promoting IL-17 production of innate lymphoid cells. We conclude that Nos2-derived NO by tissue macrophages promotes MIP, in contrast to the protective effect by ROS.

Systemic inflammation in asocial BTBR T+ tf/J mice predisposes them to increased psoriatic inflammation

Autistic Spectrum disorder (ASD) is a neurobehavioral disorder characterized by defects in communication skills leading to restricted sociability. ASD has immense dysregulation in immune responses which is thought to affect neuronal system and thus behavior. ASD patients and BTBR T⁺ tf/J (BTBR) autistic mice have increased systemic inflammation due to dysfunction in innate and adaptive immune responses. Recent studies suggest that ASD patients are associated with several co-morbid autoimmune disorders including psoriasis. However underlying mechanisms for this phenomenon have not been explored. In this study, we used imiquimod (IMQ)-induced psoriatic inflammation in social C57BL/6 (C57) mice and asocial BTBR mice to investigate whether systemic inflammation in BTBR is associated with increased susceptibility to psoriatic inflammation. Our data shows that BTBR mice have increased expression of TLR7/IL-6/IL-23 in systemic DCs but not in skin as compared to C57 mice at baseline. This leads to much greater psoriatic inflammation in BTBR mice upon IMQ application than C57 mice. Consequently, BTBR mice also have higher Th17 related immune responses in the skin and systemic compartment. Overall our study suggests that systemic innate (TLR7/IL-23/IL-6 in DCs) and adaptive (Th17 related signaling) immune responses are heightened in BTBR mice at baseline which predisposes them for greater psoriatic inflammation than C57 mice upon IMQ application. This could be one of the reasons for increased psoriatic inflammation in patients with ASD. Therapies that aim to decrease immune activation may not only benefit ASD-associated neurobehavioral abnormalities but also comorbid disorders such as psoriasis.

Patterns of peripheral joint involvement in psoriatic arthritis-Symmetric, ray and/or row?

OBJECTIVE

We sought to examine whether joint involvement in psoriatic arthritis (PsA) follows a symmetric, ray, and/or row pattern using longitudinal data.

METHODS

Data on activity and clinical damage of the joints of the hands and feet were obtained from a PsA cohort. For each analysis (symmetry, ray or row) for each outcome (joint damage and activity) expected values for table cells under the null hypothesis that joints progress independently to damage or activity were calculated based on a logistic regression model with patient level random effects for the probability of involvement developing between clinic visits. To determine the consistency of observed with expected values, goodness-of-fit tests were performed.

RESULTS

Data from 704 patients were available. The 511 (552) patients with no hand (foot) damage at clinic entry were used for analyses of hand (foot) damage. When considering joint damage, there was strong evidence against independence of joint involvement based on evident symmetric patterns. There was little suggestion of ray patterns of joint damage. There was considerable evidence for row pattern of involvement of joints. When considering joint activity, symmetric patterns were also evident but, unlike joint damage, there was evidence of ray patterns, most notably in the hands. There was also evidence for row pattern involvement.

CONCLUSION

Patterns of peripheral joint involvement seen over time in PsA patients, demonstrate consistency with expected ray patterns of disease activity, especially in the hands, but there is also considerable evidence for symmetric and row patterns for both joint damage and activity.

Bariatric Surgery and the Incidence of Psoriasis and Psoriatic Arthritis in the Swedish Obese Subjects Study

OBJECTIVE

The aim of this study was to assess the effect of bariatric surgery (vertical gastroplasty, gastric banding, or gastric bypass) compared with usual care on the incidence of psoriasis and psoriatic arthritis (PsA) in the Swedish Obese Subjects study.

METHODS

This report includes 1,991 subjects who underwent bariatric surgery and 2,018 controls with obesity from the SOS study; none of them had psoriasis or PsA at baseline. Information about psoriasis and PsA diagnosis was retrieved through the Swedish National Patient Register and questionnaires.

RESULTS

During follow-up for up to 26 years, bariatric surgery was associated with a lower incidence of psoriasis compared with usual care (number of events = 174; hazard ratio 0.65; 95% CI: 0.47-0.89; P = 0.008). Both smoking and a longer duration of obesity were independently associated with a higher risk for psoriasis. No significant difference was detected among the three surgical procedures in terms of lowering the risk of developing psoriasis. The association between bariatric surgery and psoriasis incidence was not influenced by baseline confounders. No significant difference in the risk of developing PsA (number of events = 46) was detected when comparing the surgery and the control groups.

CONCLUSIONS

This study shows that bariatric surgery is associated with a lower risk of developing psoriasis compared with usual care.

Enthesitis of the hands in psoriatic arthritis: an ultrasonographic perspective

Psoriatic arthritis is a systemic inflammatory disease in which enthesitis and dactylitis are two of the main hallmarks of the disease. In the last years, ultrasonography is increasingly playing a key role in the diagnosis of psoriatic arthritis and ultrasonography of the entheses, particularly of the lower limbs, is commonly used to assess patients with that disease. New advancements in ultrasound equipment using high frequencies probes allowed us also to identify and characterize the involvementof the entheses of the hand in psoriatic arthritis, confirming the results of the experimental models of the disease and the theory of the sinovial-entheseal complex, even in small joints.

Peripheral blood CD8+ T-cell profiles in patients with psoriatic arthritis: a cross-sectional case-control study

OBJECTIVE

While CD4+ T-cells are traditionally regarded as the main pathogenic T-cell subpopulation in psoriatic arthritis (PsA), the role of circulating CD8+ T-cells remains poorly characterized. We evaluated the differential representation of CD8+ T-cell subpopulations in peripheral blood (PB) of PsA patients.

PATIENTS AND METHODS

CD8+IL-17+, CD8+IFNγ+ and CD8+IL-17-IL-22+ T-cells were evaluated by flow-cytometry in 25 consecutive PsA patients, 7 rheumatoid arthritis (RA) patients, 16 patients with psoriasis, and 26 healthy controls (HC).

RESULTS

We observed a significant expansion of circulating IFN-γ producing CD8+ T-cells in PsA when compared to psoriasis [21.2 (6.9-55.8)% vs. 3.8 (0.7-11.8)%, p < 0.0001] and HC samples [21.2 (6.9-55.8)% vs. 4.05 (0.44-19.8)%, p < 0.0001]. A frequency of circulating IFN-γ producing CD8+T-cells ≥ 9% distinguished PsA from psoriasis patients with a specificity of 84% and a sensitivity of 87.5% [AUC = 0.9 (0.80-0.99), p < 0.0001]. In addition, we found a significant expansion of circulating IL-17 producing CD8+ T cells in RA patients when compared to PsA, psoriasis and HC samples. By contrast, there were no significant between-group differences in the prevalence of circulating IL-22 producing CD8+ T-cells. In PsA patients there was a significant correlation between number of swollen joints and frequency of circulating IFN-γ producing CD8+ T-cells, and between extent and severity of psoriasis and frequency of circulating IL-17 producing CD8+ T-cells.

CONCLUSIONS

Circulating IFNγ-producing CD8+ T-cells are raised in PsA when compared to psoriasis, suggesting a potential pathogenetic involvement of CD8+ T-cells and IFNγ production in chronic joint inflammation and damage. The significant enrichment of circulating IL-17 producing CD8+ T-cells in RA when compared to PsA warrants functional characterization and confirmation in larger studies. We found no significant enrichment of circulating IL-22 producing CD8+ T-cells in PsA, RA and psoriasis.

Residual disease activity and treatment adjustments in psoriatic arthritis in current clinical practice

BACKGROUND

With expanding therapeutic possibilities for treatment of psoriatic arthritis (PsA) it will be increasingly important to determine residual disease and define when to adjust treatment. The rationale behind treatment decisions in current daily clinical practice and the relationship with residual disease activity has not been investigated. The aim of this study was to assess current clinical practice on defining residual disease and subsequent treatment decisions made in PsA patients.

METHODS

This cross-sectional study scored disease activity and treatment decisions prospectively in 142 consecutive PsA patients visiting the outpatient clinic for routine follow up. Disease activity parameters were scored by patient and the treating rheumatologist; the rheumatologist additionally registered his opinion on the presence of remaining disease activity despite current treatment (further mentioned as remaining disease) and subsequent treatment decisions.

RESULTS

Two thirds (90/142) of patients had remaining disease activity according to the treating rheumatologist. Almost half (46%) of these patients had moderate to high disease activity according to the clinical Disease Activity Index for Psoriatic Arthritis (cDAPSA). Residual disease activity was determined by joint disease and pain rather than by active psoriasis. Demographic and clinical features were similar between groups with or without residual disease. Among patients with remaining disease activity, 74% were treated with either a conventional synthetic disease-modifying anti-rheumatic drug (csDMARD) only or a first TNF-inhibiting biological agent, suggesting opportunities for treatment modification. However, treatment adjustment was initiated in only 21 (23%) of the 90 patients with residual disease. When comparing patients with remaining disease activity with and without treatment adjustment, we found no differences in objective disease activity measures, such as joint counts and patient scores. These data suggest that treatment is not adjusted in a large majority of patients with residual disease activity, although options for treatment changes are available.

CONCLUSIONS

Remaining disease activity is present in almost two thirds of patients with PsA when scored by the treating rheumatologist, but triggers treatment adjustment in only a minority. Further research to understand why disease activity does not lead to treatment adjustment is required to enable implementation of treatment strategies in clinical practice.

[What‘s the appearance of psoriasis]

Psoriatic disorders are a visual diagnosis. Aside from several subtypes of skin psoriasis, skin appendages such nails are often affected. The burden of disease is defined by the disease activity (extent of affliction of skin) as well as restriction of quality of life. Validated scores are a good tool for the evaluation.

[Osteopecilia associated with psoriatic arthritis]

Osteopecilia is a benign and rare condensing osteopathy. Its association with inflammatory rheumatism is very rare. We here report the case of a 25-year old patient with skin psoriasis, presenting with groin pain of inflammatory origin. Physical examination showed limitation of hip motions, lower limb-length inequality and pain on right sacroiliac mobilization. Laboratory tests showed inflammatory syndrome and negative immunological assessment. The radiograph of the pelvis revealed osteopecilia associated with destructive coxitis. CT scan of the pelvis showed coxitis and osteopecilia associated with bilateral sacroiliitis. The diagnosis of psoriatic arthritis associated with osteopecilia was retained. The patient was treated with methotrexate and NSAIDS. Osteopecilia usually is unexpectedly detected. Diagnostic radiology is essential to avoid unnecessary explorations and treatments.

Role and Function of A2A and A₃ Adenosine Receptors in Patients with Ankylosing Spondylitis, Psoriatic Arthritis and Rheumatoid Arthritis

Rheumatoid arthritis (RA), ankylosing spondylitis (AS) and psoriatic arthritis (PsA) are chronic inflammatory rheumatic diseases that affect joints, causing debilitating pain and disability. Adenosine receptors (ARs) play a key role in the mechanism of inflammation, and the activation of A_2A and A₃AR subtypes is often associated with a reduction of the inflammatory status. The aim of this study was to investigate the involvement of ARs in patients suffering from early-RA (ERA), RA, AS and PsA. Messenger RNA (mRNA) analysis and saturation binding experiments indicated an upregulation of A_2A and A₃ARs in lymphocytes obtained from patients when compared with healthy subjects. A_2A and A₃AR agonists inhibited nuclear factor κ-light-chain-enhancer of activated B cells (NF-κB) activation and reduced inflammatory cytokines release, such as tumor necrosis factor-α (TNF-α), interleukin (IL)-1β and IL-6. Moreover, A_2A and A₃AR activation mediated a reduction of metalloproteinases (MMP)-1 and MMP-3. The effect of the agonists was abrogated by selective antagonists demonstrating the direct involvement of these receptor subtypes. Taken together, these data confirmed the involvement of ARs in chronic autoimmune rheumatic diseases highlighting the possibility to exploit A_2A and A₃ARs as therapeutic targets, with the aim to limit the inflammatory responses usually associated with RA, AS and PsA.