Are psoriasis and psoriatic arthritis the same disease? The IL-23/IL-17 axis data

From Psoriasis to Psoriatic Arthritis: Decoding the Impact of Treatment Modalities on the Prevention of Psoriatic Arthritis

INTRODUCTION

Biologic therapies are licensed for both psoriasis (PsO) and psoriatic arthritis (PsA) with some electronic medical record data suggest that IL (Interleukin)-23 blockers might be more protective in PsA prevention than TNF blockers; however, the findings have been inconsistent. Higher Psoriasis Area and Severity Index (PASI) scores have also been linked to an increased PsA risk. To clarify these unresolved issues we investigated biologic agents, methotrexate, phototherapy, and topical therapy for PsA prevention in patients with psoriasis.

METHODS

This retrospective cohort study analyzed data from 58,671 patients with psoriasis from the Israeli Meuhedet Health Services Organization database was evaluated for incident PsA. Patients were categorized on the basis of treatment: group 1, topical therapy; group 2, phototherapy; group 3, conventional disease-modifying antirheumatic drugs (cDMARDs; methotrexate); group 4, biologic DMARDs which was also stratified according to biologic class.

RESULTS

The PsA incidence rate was lower in the biologic agents' group versus the methotrexate group (HR 0.46 [95% CI 0.35-0.62]). The incidence rates per 100 person-years varied across biologic treatment groups, with the anti‑IL‑12/23 or anti‑IL‑23p19 group at 4.57, the anti-IL-17 group at 4.35, and the TNF inhibitor group at 2.55. No differences were found between various biological agents in terms of preventing PsA. The phototherapy group exhibited a higher PsA development rate than the topical therapy group (HR 1.85 [95% CI 1.65-2.07]).

CONCLUSION

Biological agents are more effective than methotrexate in reducing incident PsA in patients with psoriasis. This lower rate of PsA on topical therapy compared to phototherapy supports the importance of psoriasis severity as a risk factor.

Risk of peripheral neuropathy in patients with psoriasis and psoriatic arthritis. A prospective cohort study

INTRODUCTION/AIMS

Laboratory and clinical data suggest a link between neurologically mediated inflammation and psoriasis, but the risk and features of peripheral neuropathy in psoriasis or psoriatic arthritis remain unknown. The aim of this exploratory study was to evaluate the risk and to describe the features of peripheral neuropathy in patients with psoriasis and psoriatic arthritis.

METHODS

One hundred patients with psoriasis and/or psoriatic arthritis and 100 control subjects were consecutively enrolled. Diagnostic confirmation included electrophysiological examination, skin biopsy, and nerve ultrasound for confirmed polyneuropathy.

RESULTS

Nine patients were diagnosed with confirmed polyneuropathy, while none of the control subjects had the condition (relative risk [RR] = 19.00, 95% confidence interval [CI] = 1.12-322.11). Specific relative risks for polyneuropathy were 22.09 (95% CI = 1.17-416.43) in psoriasis patients and 18.75 (95% CI = 1.07-327.62) in psoriatic arthritis patients. The observed polyneuropathy in all nine patients was length-dependent, symmetrical, and predominantly sensory, with minimal or no disability. Comorbidities and exposure to therapies known to increase the risk of polyneuropathy were more frequent in psoriasis and/or psoriatic arthritis patients compared to controls (42% vs. 4%, p = .0001). Analyzing data after excluding possible contributory causes, the risk of polyneuropathy in patients with psoriasis and/or psoriatic arthritis was not significant.

DISCUSSION

Psoriasis and psoriatic arthritis appear to be associated with an increased risk of polyneuropathy. This increased risk seems to be linked to the higher prevalence of contributing factors for polyneuropathy, rather than a direct increase in neuropathy risk specifically related to psoriasis and psoriatic arthritis.

Switching patterns of biological drugs in patients with psoriasis and psoriatic arthritis: insight from the VALORE database network

BACKGROUND

Switch patterns among different biologics and from originators to biosimilars (and vice versa) can be complex in patients with psoriasis (PsO) and psoriatic arthritis (PsA).

OBJECTIVE

The aim of this study was to describe switching patterns of biological drugs in PsO/PsA patients and to explore predictors of multiple switches and switch-back.

RESEARCH DESIGN AND METHODS

A large-scale retrospective cohort study was conducted using the Italian VALORE database. Bio-naïve users treated for PsO/PsA during 2010-2022 were included. Time to switch/swap and predictors of multiple switches and switch-back were analyzed.

RESULTS

Thirty-thousand seven hundred bio-naïve users were included. At 3 and 5 years of follow-up, patients with at least one switch/swap were 37.1% and 47.8%, respectively. The median time to first switch/swap was significantly shorter (p< 0.001) for TNF-α inhibitors (2,068 days) than anti-IL (2,780 days). At 1 year of follow-up patients starting with IL-23 switched/swapped biological therapy less frequently than those with anti-IL-12/23 and anti-IL-17 (4.9% vs. 8.7% and 9.4%, respectively). Patients starting with anti-IL-12/23 reported a significantly lower risk of multiple switches and switch-back (0.74, 95% CI, 0.67-0.83; 0.58, 95% CI, 0.44-0.77, respectively) than those with TNF-α inhibitors.

CONCLUSIONS

Patients with PsO/PsA starting with TNF-α inhibitors switch/swap more rapidly and frequently than those with anti-IL, which are also associated with a reduced risk of multiple switches during follow-up.

Structural cell heterogeneity underlies the differential contribution of IL-17A, IL-17F and IL-23 to joint versus skin chronic inflammation

The current therapeutic strategy used in immune-mediated inflammatory diseases (IMIDs) primarily targets immune cells or associated-pathways. However, recent evidence suggests that the microenvironment modulates immune cell development and responses. During inflammation, structural cells acquire a pathogenetic phenotype and the interactions with immune cells are often greatly modified. Understanding the importance of these tissue-specific interactions may allow to explain why some biologics are effective in some IMIDs but not in others. The differential effects of interleukin (IL)-17 A, IL-17F and IL-23 in joint versus skin inflammation depends on structural cell heterogeneity. In addition, the sometimes opposite effects of immune/structural cell interactions on the production of these cytokines illustrate the importance of these cells in chronic inflammation, using the examples of rheumatoid arthritis, psoriasis and spondyloarthritis. This review describes these concepts, shows their interests through clinical observations, and finally discusses strategies to optimize therapeutic strategies.

Dupilumab-associated inflammatory arthritis: a literature review

Dupilumab is a fully human monoclonal antibody that acts by inhibiting the interleukin (IL)-4 receptor subunit α, and hence the IL-4 and IL-13 signalling pathway. Dupilumab treatment has been linked to the onset of T helper 17-driven inflammatory diseases, including cases of seronegative arthritis and enthesitis. To date, dupilumab-associated inflammatory arthritis (DAIA) represents a relatively unknown adverse event, initially reported in single cases or case series reports. Indeed, the onset of DAIA may not be promptly recognized, and is probably underestimated. Here we have reviewed the available English literature regarding arthritis and enthesitis onset during dupilumab treatment for atopic dermatitis, aiming to improve rapid recognition and thus prompt treatment of these diseases.

Effects of tumor necrosis factor-alpha inhibitors on lipid profiles in patients with psoriasis: a systematic review and meta-analysis

Background

There is no consensus on the effect of tumor necrosis factor-alpha (TNF-alpha) inhibitors on lipid profiles in patients with psoriasis. This study aimed to investigate the effects of TNF-alpha inhibitors on lipid profiles (triglycerides, total cholesterol, low-density lipoprotein, or high-density lipoprotein) in patients with psoriasis.

Methods

We searched PubMed, Embase, and Cochrane Library databases for articles published before October 17, 2023. Four TNF-alpha inhibitors (infliximab, etanercept, adalimumab, and certolizumab) were included in our study. (PROSPERO ID: CRD42023469703).

Results

A total of twenty trials were included. Overall results revealed that TNF-alpha inhibitors elevated high-density lipoprotein levels in patients with psoriasis (WMD = 2.31; 95% CI: 0.96, 3.67; P = 0.001), which was supported by the results of sensitivity analyses excluding the effect of lipid-lowering drugs. Subgroup analyses indicated that high-density lipoprotein levels were significantly increased in the less than or equal to 3 months group (WMD = 2.88; 95% CI: 1.37, 4.4; P < 0.001), the etanercept group (WMD = 3.4; 95% CI = 1.71, 5.09, P < 0.001), and the psoriasis group (WMD = 2.52; 95% CI = 0.57, 4.48, P = 0.011). Triglyceride levels were significantly increased in the 3 to 6-month group (WMD = 4.98; 95% CI = 1.97, 7.99, P = 0.001) and significantly decreased in the 6-month and older group (WMD = -19.84; 95% CI = -23.97, -15.7, P < 0.001). Additionally, Triglyceride levels were significantly increased in the psoriasis group (WMD = 5.22; 95% CI = 2.23, 8.21, P = 0.001).

Conclusion

Our results revealed that TNF-alpha inhibitors might temporarily increase high-density lipoprotein levels in patients with psoriasis. However, changes in triglycerides were not consistent among the different durations of treatment, with significant increases after 3 to 6 months of treatment. Future prospective trials with long-term follow-up contribute to confirming and extending our findings.

Systematic Review Registration

https://www.crd.york.ac.uk/PROSPERO/, identifier CRD42023469703.

Inflammatory and Immunomodulatory Effects of Tripterygium wilfordii Multiglycoside in Mouse Models of Psoriasis Keratinocytes

OBJECTIVE

To determine the role of Tripterygium wilfordii multiglycoside (TGW) in the treatment of psoriatic dermatitis from a cellular immunological perspective.

METHODS

Mouse models of psoriatic dermatitis were established by imiquimod (IMQ). Twelve male BALB/c mice were assigned to IMQ or IMQ+TGW groups according to a random number table. Histopathological changes in vivo were assessed by hematoxylin and eosin staining. Ratios of immune cells and cytokines in mice, as well as PAM212 cell proliferation in vitro were assessed by flow cytometry. Pro-inflammatory cytokine expression was determined using reverse transcription quantitative polymerase chain reaction.

RESULTS

TGW significantly ameliorated the severity of IMQ-induced psoriasis-like mouse skin lesions and restrained the activation of CD45+ cells, neutrophils and T lymphocytes (all P<0.01). Moreover, TGW significantly attenuated keratinocytes (KCs) proliferation and downregulated the mRNA levels of inflammatory cytokines including interleukin (IL)-17A, IL-23, tumor necrosis factor α, and chemokine (C-X-C motif) ligand 1 (P<0.01 or P<0.05). Furthermore, it reduced the number of γ δ T17 cells in skin lesion of mice and draining lymph nodes (P<0.01).

CONCLUSIONS

TGW improved psoriasis-like inflammation by inhibiting KCs proliferation, as well as the associated immune cells and cytokine expression. It inhibited IL-17 secretion from γ δ T cells, which improved the immune-inflammatory microenvironment of psoriasis.

Comparison and subsets analysis of peripheral CD4+T cells in patients with psoriasis and psoriatic arthritis

Psoriatic arthritis (PsA) is a disease that transformed from psoriasis (PsO), and its underlying mechanisms are still not fully understood. Overactivation of the immune system is a key factor driving inflammatory diseases. Our goal is to define the unbalanced subsets of peripheral blood CD4 +T cells between PsO and PsA patients. Blood samples from 43 patients (23 PsA and 20 PsO) and 36 healthy donors (HD) were studied. Peripheral blood mononuclear cells (PBMC) were separated from blood and underwent fluorescent staining to assess CD4+T cell subsets by flow cytometry. We found that frequencies of various CD4+T cells including Th1, Th2, Th17, and Tfh were higher in the patients with PsO or PsA than those of healthy donors, indicating the general expansion of CD4+T cells in inflammatory conditions. More importantly, we observed the significant imbalance of Th1/Th2 between patients with PsO and PsA. Pearson correlation analysis showed that Th1/Th2 ratio was positively correlated with disease activity in psoriatic arthritis (DAPSA), Tfh/Tfr ratio was positively correlated with DAPSA score and visual analogue scale (VAS) score in PsA patients. Together, our results highlight the CD4+T cell changes in the transition from PsO to PsA, may contribute to early assessment and intervention.

Inflammatory Cytokines in Psoriatic Arthritis: Understanding Pathogenesis and Implications for Treatment

Psoriatic arthritis (PsA) is a persistent, inflammatory disease that affects individuals with psoriasis, arthritis, and enthesitis. Research has demonstrated that inflammatory cytokines such as tumor necrosis factor-alpha (TNF-α), interleukin-23 (IL-23), and interleukin-17 (IL-17) play a pivotal role in both the onset and progression of PsA. These cytokines are generated by activated immune cells and stimulate the attraction of inflammatory cells to the synovium and joint tissues, resulting in the deterioration of cartilage and bone. The blocking of these cytokines has become a successful treatment strategy for PsA, as biological drugs that inhibit TNF-α, IL-23, and IL-17 have demonstrated notable clinical benefits. The association between PsA and other types of inflammatory cytokines or chemokines, excluding TNF-α, IL-23, and IL-17, has been extensively investigated in numerous studies. These findings may provide a chance for the discovery of novel therapeutic agents targeting other molecules, distinct from the currently approved biologics and targeted synthetic disease-modifying anti-rheumatic drugs. In this review, we discuss the current understanding of the role of inflammatory cytokines in PsA pathogenesis and clinical implications of targeting these cytokines for PsA treatment.

IL-17A exacerbates psoriasis in a STAT3 overexpressing mouse model

Background

Psoriasis is an autoimmune skin disease characterized by immunocyte activation, excessive proliferation, and abnormal differentiation of keratinocytes. Signal transducers and activators of transcription 3 (STAT3) play a crucial role in linking activated keratinocytes and immunocytes during psoriasis development. T helper (Th) 17 cells and secreted interleukin (IL)-17A contribute to its pathogenesis. IL-17A treated STAT3 overexpressing mouse model might serve as an animal model for psoriasis.

Methods

In this study, we established a mouse model of psoriasiform dermatitis by intradermal IL-17A injection in STAT3 overexpressing mice. Transcriptome analyses were performed on the skin of wild type (WT), STAT3, and IL-17A treated STAT3 mice. Bioinformatics-based functional enrichment analysis was conducted to predict biological pathways. Meanwhile, the morphological and pathological features of skin lesions were observed, and the DEGs were verified by qPCR.

Results

IL-17A treated STAT3 mice skin lesions displayed the pathological features of hyperkeratosis and parakeratosis. The DEGs between IL-17A treated STAT3 mice and WT mice were highly consistent with those observed in psoriasis patients, including S100A8, S100A9, Sprr2, and LCE. Gene ontology (GO) analysis of the core DEGs revealed a robust immune response, chemotaxis, and cornified envelope, et al. The major KEGG enrichment pathways included IL-17 and Toll-like receptor signaling pathways.

Conclusion

IL-17A exacerbates psoriasis dermatitis in a STAT3 overexpressing mouse.

Psoriatic disease and non-alcoholic fatty liver disease shared pathogenesis review

Psoriatic disease (PD) and non-alcoholic fatty liver disease (NAFLD) potentially share disease pathways given the numerous inflammatory pathways involved in both diseases and a higher prevalence of NAFLD in PD patients.  Metabolic syndrome and obesity are a key link between the two diseases, but even when controlling for this, associations between both diseases are still seen. Therapeutics that impact metabolic or inflammatory pathways may be impactful in both PD and NAFLD. In this review, we describe common inflammatory pathways contributing to both PD and NAFLD and critically review the potential impact of treatments for and on both diseases.

Subclinical high-resolution chest CT scan features in psoriasis

BACKGROUND

Although psoriasis is considered a systemic disease, no clear association has been established between psoriasis and lung diseases. This study aims to detect and describe subclinical pulmonary involvement in psoriasis patients with various degrees of cutaneous manifestations.

METHODS

Adult psoriasis patients with no known active pulmonary disease or respiratory symptoms were screened for subclinical pulmonary manifestations and possible parenchymal changes using high-resolution computed tomography (HRCT) scan of the chest. Patients were classified according to the severity of skin manifestations. The clinical characteristics and radiographic findings of these patients were evaluated.

RESULTS

Fifty-nine patients with psoriasis were included, among which 47 (79.7%) had abnormal HRCT scan features. Micronodules were the most common detected lung lesions (66.1%), followed by nonspecific interstitial changes (32.2%), including pleuro-parenchymal band/atelectasis, scarring, and focal ground-glass opacities. Other HRCT findings included emphysematous changes and calcified granulomas. Abnormal HRCT findings correlated with older age and duration of psoriasis but not with the severity of skin manifestations.

CONCLUSIONS

Micronodules and minor focal nonspecific interstitial changes were the most detected lung alterations in patients with psoriasis. These findings of the pilot study highlight a possible pulmonary involvement in patients with psoriasis. Larger multicenter studies are needed to clarify these findings further.

LIMITATIONS

A major limitation of the study, is the lack of a control group with similar radiologic findings of different conditions done in the same geographical region.

Ex vivo cytokine production in psoriatic disease: Towards specific signatures in cutaneous psoriasis and peripheral psoriatic arthritis

Objectives

Psoriatic arthritis (PsA) and cutaneous psoriasis (PsO) are different phenotypes of psoriatic disease (PsD), whose underlying specific mechanisms remain incompletely understood. As cytokines are key elements to induce and tune up immune responses to drive inflammatory diseases, our objective was to assess whether clinical features, disease phenotype and PsA and PsO activity were associated with a particular ex vivo cytokine production profile.

Methods

Forty-eight patients (37 PsA and 11 PsO) and 11 healthy subjects (HS) were studied. Cytokine production by peripheral blood mononuclear cells (PBMC) that were either unstimulated, or stimulated with LPS or anti-CD3/CD28 antibodies, were analysed by multiplex assay in the culture supernatants.

Results

Cytokine signature of PsD includes a high level of TNFα in supernatants of LPS-stimulated PBMC, higher levels of IL-6 and lower levels of IFN-γ and IL-17A after CD3-CD28 stimulation, as well as higher spontaneous IL-1RA and TNFα production compared to HS. High body mass index (BMI) was associated with lower levels of IL-1β, and metabolic syndrome with lower levels of IFN-γ after LPS stimulation. In PsD, dermatological activity was related with higher IL-17A level, while rheumatic activity was linked with lower levels of IFN-γ and TNFα. Comparing each PsD subtype to HS, IL-1β and IL-6 productions are higher when using LPS stimulation in PsO patients with higher levels of IL-1β and IL-1α in peripheral PsA patients after CD3/CD28 stimulation. LPS stimulation induced high levels of IL-17A in peripheral PsA compared to axial PsA. PsA patients with axial PsA share some features with PsO but shows a distinct cytokine pattern compared to peripheral PsA.

Conclusion

PsO and the different PsA subtypes exhibit distinct ex vivo cytokine production profiles and common features of the so-called PsD. Analysis of IL-1 cytokine family and IL-6 seems to be of particular interest to distinguish PsO and peripheral PsA since it depends on monocytes in PsO and T-lymphocytes in peripheral PsA. Peripheral cytokine profiles are influenced by rheumatic and dermatological activity of the disease, and also by metabolic syndrome features. Our results highlight the crucial role of immune cell interactions with different patterns of interaction depending on clinical phenotype.

The regulatory mechanism and potential application of IL-23 in autoimmune diseases

IL-23 is a heterodimeric pro-inflammatory cytokine secreted by dendritic cells and macrophages that belongs to the IL-12 family. It has pro-inflammatory effects and is a key cytokine and upstream regulatory cytokine involved in protective immune responses, stimulating the differentiation and proliferation of downstream effectors such as Th17 cells. It is expressed in various autoimmune diseases such as psoriasis, systemic lupus erythematosus (SLE), rheumatoid arthritis (RA). The IL-23/TH17 axis formed by IL-23 and TH17 has been confirmed to participate in autoimmune diseases pathogenesis. IL-23R is the receptor for IL-23 and plays an activating role. Targeting IL-23 is currently the main strategy for the treatment of various autoimmune diseases. In this review we summarized the mechanism of action and clinical application potential of IL-23 in autoimmune diseases by summarizing the latest research results and reviewing the literature, which would help to further understand IL-23 and provide a theoretical basis for future clinical targeting and drug development.

IL-23 in axial spondyloarthritis and psoriatic arthritis: a good fit for biological treatment?

INTRODUCTION

Interleukin 23 (IL-23) is a pro-inflammatory cytokine that plays a protective role against bacterial and fungal infections. However, the dysregulation of the IL-23/IL-17 axis provides a solid substrate for the development of various inflammatory diseases, such as psoriatic arthritis (PsA) and ankylosing spondylitis (AS).

AREAS COVERED

In different clinical trials, several drugs against IL-23 have shown efficacy and safety towards PsA, with excellent results on skin and joint scores. However, the same drugs did not show the same efficacy in AS, suggesting that IL-23 may not be a relevant driver of the pathobiology and clinical symptoms of active axial spondyloarthritis (axSpA).

EXPERT OPINION

These drugs have shown an excellent efficacy and a good safety profile towards PsA, while in AS the efficacy of the IL-23 blockade is lacking for reasons not yet known. Several hypotheses have been reported, but further studies will be needed for a greater understanding. This suggests the involvement of pathways or mechanisms for the development of SpA that remain unknown. In order to allow a wide use of IL-23 inhibitors, further clinical trials and long-term prospective studies are necessary.

Lipocalin 2 Participates in the Epidermal Differentiation and Inflammatory Processes of Psoriasis

As a multifunctional cytokine, lipocalin 2 is weakly expressed in skin and serum under normal conditions. However, it is over-expressed by neutrophils and keratinocytes in the skin lesions and sera in several skin diseases. Recent studies demonstrated that lipocalin 2 participates in the pathogenesis of psoriasis by exerting versatile effects on skin resident cells and infiltrating immune cells. Lipocalin 2 inhibits the synthesis of keratin, involucrin, and loricrin in keratinocytes, leading to epidermal parakeratosis via the Tcf7l1-lipocalin 2 signaling axis. It also recruits inflammatory cells such as T cells and neutrophils into skin lesions via the IL-23/IL17, p38-MAPK, and ERK-1/2 signaling pathways. Additionally, lipocalin 2 and other cytokines such as IL-17 have the synergetic effects on skin cells. The neutralization of lipocalin 2 or relevant cytokines can alleviate psoriasis, verifying that lipocalin 2 is an effective interfering target for psoriasis. In this review, we summarize the roles of lipocalin 2 in the processes of psoriatic inflammation and the promising therapeutic strategies based on lipocalin 2-related molecules.

Psoriasis to Psoriatic Arthritis: The Application of Proteomics Technologies

Psoriatic disease (PsD) is a spectrum of diseases that affect both skin [cutaneous psoriasis (PsC)] and musculoskeletal features [psoriatic arthritis (PsA)]. A considerable number of patients with PsC have asymptomatic synovio-entheseal inflammations, and approximately one-third of those eventually progress to PsA with an enigmatic mechanism. Published studies have shown that early interventions to the very early-stage PsA would effectively prevent substantial bone destructions or deformities, suggesting an unmet goal for exploring early PsA biomarkers. The emergence of proteomics technologies brings a complete view of all involved proteins in PsA transitions, offers a unique chance to map all potential peptides, and allows a direct head-to-head comparison of interaction pathways in PsC and PsA. This review summarized the latest development of proteomics technologies, highlighted its application in PsA biomarker discovery, and discussed the possible clinical detectable PsA risk factors in patients with PsC.

Delphinidin diminishes in vitro interferon-γ and interleukin-17 producing cells in patients with psoriatic disease

The anthocyanidin delphinidin reduces psoriasiform lesions and inflammatory mediators in human cell culture systems. Its role in psoriatic disease has not yet been investigated. We assessed delphinidin's in vitro immunomodulatory effect on ex vivo stimulated peripheral blood mononuclear cells (PBMCs) from 50 individuals [26 with psoriasis, 10 with psoriatic arthritis (PsA) and 14 healthy controls (HCs)]. Cells were either left untreated or stimulated with PMA plus ionomycin in the presence or absence of delphinidin. Intracellular production of interferon-γ (IFNγ), interleukin-17A (IL-17A), and interleukin-10 (IL-10) was measured flow cytometrically. Delphinidin dose-dependently reduced IFNγ⁺ T cells from patients and HCs. The mean IFNγ decrease in CD4⁺ T subpopulations was 42.5 ± 28% for psoriasis patients, 51.8 ± 21.5% for PsA patients and 49 ± 17% for HCs (p < 0.001 for all). Similarly, IFNγ reduction in CD8⁺ T cells was 34 ± 21.6% for psoriasis patients, 47.1 ± 22.8% for PsA and 44.8 ± 14.3% for HCs (P < 0.001 for all). An inhibitory effect of delphinidin was also noted in IFNγ producing NKs and NKTs from psoriasis individuals. Delphinidin also significantly decreased IL-17⁺ CD4⁺ T cells in all tested subjects, with marginal effect on the increase of IL-10-producing T regulatory subsets. In conclusion, delphinidin exerts a profound in vitro anti-inflammatory effect in psoriasis and psoriatic arthritis by inhibiting IFNγ⁺ innate and adaptive cells and T helper (Th) 17 cells. If this effect is also exerted in vivo, delphinidin may be regarded as a nutraceutical with immunosuppressive potential.

DNA Methylation Patterns in CD8+ T Cells Discern Psoriasis From Psoriatic Arthritis and Correlate With Cutaneous Disease Activity

Background: Psoriasis is a T cell-mediated chronic autoimmune/inflammatory disease. While some patients experience disease limited to the skin (skin psoriasis), others develop joint involvement (psoriatic arthritis; PsA). In the absence of disease- and/or outcome-specific biomarkers, and as arthritis can precede skin manifestations, diagnostic and therapeutic delays are common and contribute to disease burden and damage accrual.

Objective: Altered epigenetic marks, including DNA methylation, contribute to effector T cell phenotypes and altered cytokine expression in autoimmune/inflammatory diseases. This project aimed at the identification of disease-/outcome-specific DNA methylation signatures in CD8⁺ T cells from patients with psoriasis and PsA as compared to healthy controls.

Method: Peripheral blood CD8⁺ T cells from nine healthy controls, 10 psoriasis, and seven PsA patients were collected to analyze DNA methylation marks using Illumina Human Methylation EPIC BeadChips (>850,000 CpGs per sample). Bioinformatic analysis was performed using R (minfi, limma, ChAMP, and DMRcate packages).

Results: DNA methylation profiles in CD8⁺ T cells differentiate healthy controls from psoriasis patients [397 Differentially Methylated Positions (DMPs); 9 Differentially Methylated Regions (DMRs) when ≥CpGs per DMR were considered; 2 DMRs for ≥10 CpGs]. Furthermore, patients with skin psoriasis can be discriminated from PsA patients [1,861 DMPs, 20 DMRs (≥5 CpGs per region), 4 DMRs (≥10 CpGs per region)]. Gene ontology (GO) analyses considering genes with ≥1 DMP in their promoter delivered methylation defects in skin psoriasis and PsA primarily affecting the BMP signaling pathway and endopeptidase regulator activity, respectively. GO analysis of genes associated with DMRs between skin psoriasis and PsA demonstrated an enrichment of GABAergic neuron and cortex neuron development pathways. Treatment with cytokine blockers associated with DNA methylation changes [2,372 DMPs; 1,907 DMPs within promoters, 7 DMRs (≥5 CpG per regions)] affecting transforming growth factor beta receptor and transmembrane receptor protein serine/threonine kinase signaling pathways. Lastly, a methylation score including TNF and IL-17 pathway associated DMPs inverse correlates with skin disease activity scores (PASI).

Conclusion: Patients with skin psoriasis exhibit DNA methylation patterns in CD8⁺ T cells that allow differentiation from PsA patients and healthy individuals, and reflect clinical activity of skin disease. Thus, DNA methylation profiling promises potential as diagnostic and prognostic tool to be used for molecular patient stratification toward individualized treatment.

Dihydroartemisinin Alleviates Imiquimod-Induced Psoriasis-like Skin Lesion in Mice Involving Modulation of IL-23/Th17 Axis

Background: Psoriasis is a T help 17 (Th17) cell-mediated chronic inflammatory skin disease. Recent studies have shown that dihydroartemisinin (DHA) can significantly reduce experimental autoimmune encephalomyelitis and rheumatoid arthritis by regulating Th17 cells.

Objective: To verify whether DHA can improve the symptoms of psoriasis and to further explore the possible mechanism.

Methods: The efficiency of DHA was preliminary detected on human keratinocytes (HaCaT) cells in psoriatic condition. Then, imiquimod-induced psoriasis-like model in BALB/c mice was established to evaluate the effects of DHA in vivo.

Results: Under the stimulation of tumor necrosis factor-α (TNF-α) and interferon-γ (IFN-γ), DHA inhibited the proliferation of HaCaT cells and significantly affected the mRNA expression levels of IFN-γ, interleukin (IL), IL-17A and IL-23. DHA treatment reduced the severity of psoriasis-like skin and resulted in less infiltration of immune cells in skin lesions. DHA restored the expression of IFN-γ, IL-17A, and IL-23 in skins, as well as a decrease of cytokines and chemokines in skin supernatant. DHA also altered the cellular composition in the spleen, which is the makeup of the T cells, dendritic cells (DCs), and macrophages. DHA recovered Th17-related profile with decreased frequency of IL-17⁺CD4⁺T cells from splenocyte of mice. Furthermore, DHA also inhibited the concentration of IL-17 from Th17 cells and the expression of Th17 cell-related transcription factors retinoid-related orphan receptor-gamma t (ROR-γt) in vitro. In addition, phosphorylation of signal transducer and activator of transcription-3 (STAT3) was significantly reduced in DHA treatment mice, suggesting that the IL-23/Th17 axis plays a pivotal role.

Conclusion: DHA inhibits the progression of psoriasis by regulating IL-23/Th17 axis and is expected to be an effective drug for the treatment of psoriasis.

Volumetric Bone Mineral Density Measured by HR-pQCT in Patients with Psoriasis or Psoriatic Arthritis: A Systematic Review and Meta-Analysis with Trial Sequential Analysis

Bone health in psoriasis and psoriatic arthritis has been emphasized in recent years. Novel imaging modalities allow investigations into volumetric bone mineral density (vBMD) and bone microstructure in psoriatic patients. However, literature regarding vBMD measured by high-resolution peripheral quantitative computed tomography (HR-pQCT) is inconclusive. We conducted a systematic review and meta-analysis to evaluate vBMD in patients with psoriatic disease. We searched PubMed, EMBASE, Web of Science, and Cochrane Library for relevant observational studies. A random-effects meta-analysis with trial sequential analysis (TSA) was performed. The pooled mean difference (MD) and 95% confidence interval (CI) were calculated. Five studies with 780 patients were included. Patients with psoriatic disease showed a lower average vBMD than controls (MD -14.90; 95% CI -22.90 to -6.89; TSA-adjusted CI -23.77 to -6.03; I² = 41%). Trabecular vBMD and cortical vBMD results were inconclusive because of the small sample size. Patients recruited in Asia and those whose vBMD were measured at the distal radius exhibited a lower average vBMD than controls. Further research should clarify the association of psoriasis with bone microstructure and the underlying pathophysiology.

Translational Research Studies Unraveling the Origins of Psoriatic Arthritis: Moving Beyond Skin and Joints

Patients with psoriatic arthritis (PsA) are suffering from a decreased quality of life despite currently available treatments. In the latest years, novel therapies targeting the IL-17/IL-23 and TNF pathways improved clinical outcome. Despite this, remission of disease is not achieved in a considerable group of patients, continuous treatment is very often required to reach clinical remission, and prevention of PsA in patients with psoriasis (PsO) is currently impossible. A better understanding of PsA pathogenesis is required to develop novel treatment strategies that target inflammation and destruction more effectively and at an early stage of the disease, or even before clinically manifest disease. The skin is considered as one of the sites of onset of immune activation, triggering the inflammatory cascade in PsA. PsO develops into PsA in 30% of the PsO patients. Influenced by environmental and genetic factors, the inflammatory process in the skin, entheses, and/or gut may evolve into synovial tissue inflammation, characterized by influx of immune cells. The exact role of the innate and adaptive immune cells in disease pathogenesis is not completely known. The involvement of activated IL-17A+ T cells could implicate early immunomodulatory events generated in lymphoid organs thereby shaping the pathogenic inflammatory response leading to disease. In this perspective article, we provide the reader with an overview of the current literature regarding the immunological changes observed during the earliest stages of PsA. Moreover, we will postulate future areas of translational research aimed at increasing our knowledge on the molecular mechanisms driving disease development, which will aid the identification of novel potential therapeutic targets to limit the progression of PsA.

Depression and Obesity in Patients With Psoriasis and Psoriatic Arthritis: Is IL-17-Mediated Immune Dysregulation the Connecting Link?

Patients with psoriasis are frequently obese and experience anxiety or suffer from depressive disorders. The immunopathogenesis of psoriasis and indeed psoriatic arthritis is largely based on the pivotal role of IL-17/IL-23 axis, to an extent that currently monoclonal antibodies selectively inhibiting IL-17 or IL-23 are routinely used for the treatment of psoriatic diseases. Emerging data, demonstrating a decisive role for IL-17 and IL-17 producing cell subsets, such as Th17 in the induction and progression of obesity and depression has led authors to suggest that psoriatic disease, obesity and anxiety/depression may indeed be interconnected manifestation of a state of immunedysregulation, the linked being IL-17 and its related cells. We discuss this hypothetical link in depth taking into account the beneficial effects anti-IL17 and anti-IL-17 receptor inhibitors in treating psoriatic disease and the on-going debate as to whether these biologics may exert a direct or indirect effect in ameliorating concomitant obesity and depressive disorders, which are frequently noted in the same patient.

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.

Targeting the CCR6/CCL20 axis in entheseal and cutaneous inflammation

OBJECTIVES

To assess the involvement of the CCR6/CCL20 axis in psoriatic arthritis (PsA) and psoriasis (PsO) and to evaluate its potential as a therapeutic target.

METHODS

First, we quantified CCL20 levels in peripheral blood and synovial fluid of PsA patients and the presence of CCR6⁺ cells in synovial and tendon tissue. Utilizing an IL-23 minicircle DNA (MC) mouse model exhibiting key features of both PsO and PsA, we investigated CCR6 and CCL20 expression and the preventive and therapeutical effect of CCL20 blockade. Healthy tendon stromal cells were stimulated in vitro with IL-1β to assess the production of CCL20 by qPCR and ELISA. The effect of conditioned media from stimulated tenocytes in inducing T cell migration was interrogated with a transwell system.

RESULTS

We observed an upregulation of both CCR6 and CCL20 in the enthesis of IL-23 MC-treated mice, which was confirmed in human biopsies. Specific targeting of the CCR6/CCL20 axis with a CCL20 locked dimer (CCL20LD) blocked entheseal inflammation, leading to profound reductions in clinical and proinflammatory markers in the joints and skin of IL-23 MC-treated mice. The stromal compartment in the tendon was the main source of CCL20 in this model and accordingly, in vitro activated human tendon cells were able to produce this chemokine and to induce CCR6+ T cell migration, the latter of which could be blocked by CCL20LD.

CONCLUSIONS

Our studies highlight the pathogenic role of CCR6-CCL20 axis in enthesitis and raise the prospect of a novel therapeutic approach for treating patients with PsO and PsA.

Downregulation of Cathepsin B Reduces Proliferation and Inflammatory Response and Facilitates Differentiation in Human HaCaT Keratinocytes, Ameliorating IL-17A and SAA-Induced Psoriasis-Like Lesion

Psoriasis is a common inflammatory dermatology disease. Strongly expressed serum amyloid A (SAA) promotes psoriasis exacerbation through inducing IL-17 secretion. What's more, SAA can stimulate the release of cathepsin B. The current work was performed to demonstrate the specific effects of cathepsin B silencing on inflammatory response, proliferation, and differentiation of IL-17A and SAA-induced keratinocytes and to report the precise role of cathepsin B in psoriasis-like lesion. HaCaT keratinocytes received treatment with IL-17A (0, 10, 50, 100 ng/ml) or SAA (0, 1, 5, 10, 20 μg/ml) for 24 h to establish psoriasis-like keratinocytes model. HaCaT keratinocytes were transfected with small interfering RNA (siRNA)-cathepsin B for the functional experiments. Cathepsin B mRNA and protein levels were separately assessed by performing RT-qPCR and Western blot analysis. Then, CCK-8 for detection of cell proliferative capacity and Western blot assay for detection of Ki67 and PCNA expression were adopted to evaluate the influence of silenced cathepsin B on proliferation of IL-17A/SAA-induced HaCaT keratinocytes. Furthermore, IL-6, IL-1β, TNF-α, and p-NF-κB p65 were detected to assess the effects of cathepsin B knockdown on inflammatory response in IL-17A/SAA-induced HaCaT keratinocytes. In addition, assessment of KRT10, FLG, and LOR levels were applied to analyze the function of cathepsin B silencing on differentiation of IL-17A/SAA-induced HaCaT keratinocytes. Cathepsin B expression is distinctly elevated in IL-17A/SAA-induced HaCaT keratinocytes. IL-17A or SAA treatment enhanced proliferation, promoted the release of inflammatory factors, and arrested differentiation in HaCaT keratinocytes. Furthermore, downregulation of cathepsin B reduced proliferation, suppressed inflammatory response, and boosted differentiation in IL-17A/SAA-induced HaCaT keratinocytes. To sum up, cathepsin B silencing rescued excessive proliferation and inflammatory response and scarce differentiation in HaCaT keratinocytes induced by IL-17A and SAA. These findings prompted that cathepsin B might be a promising therapeutic target for psoriasis-like lesion, which helps to develop an anti-psoriatic agent.

JAK inhibitors, psoriatic arthritis, and axial spondyloarthritis: a critical review of clinical trials

INTRODUCTION

Psoriatic arthritis (PsA) and spondyloarthritis (SpA) are inflammatory arthritides associated with progressive damage, deformity and morbidity. Janus kinase (JAK) inhibitors block JAKs, cytoplasmic protein tyrosine kinases important in signal transduction and immune processes that are currently being studied as synthetic disease modifying anti-rheumatic drugs (tsDMARDs) in psoriatic arthritis and spondyloarthritis.

AREAS COVERED

This review evaluates published phase 2 and 3 clinical trial data for JAK kinase inhibitors for psoriatic arthritis and spondyloarthritis. A literature search using PubMed was conducted using the following keywords: 'psoriatic arthritis', 'ankylosing spondylitis', 'axial spondyloarthritis', 'non-radiographic axial spondyloarthritis', 'tofacitinib', 'baricitinib', 'filgotinib' and 'upadacitinib'. Mechanism of action, phase 2 and 3 clinical trial data, including efficacy and safety, are discussed.

EXPERT OPINION

JAK inhibitors are important orally administered agents conferring different degrees of selectivity toward JAK1, JAK2, and JAK3 which may have implications on efficacy and safety in PsA and SpA. Phase 2 and 3 clinical trials in PsA for tofacitinib and upadacitinib and phase 2 for filgotinib confirmed efficacy comparable to biologic DMARDs. In SpA, phase 2 and 2/3 studies confirmed significant efficacy of tofacitinib, filgotinib and upadacitinib compared to placebo. Safety was comparable to clinical trial, long-term extension, and registry data for rheumatoid arthritis.

Anti-IL-23 exerted protective effects on cerebral ischemia-reperfusion injury through JAK2/STAT3 signaling pathway

Ischemia-reperfusion frequently occurs in ischemic cerebral vascular disease, during which the inflammatory signaling plays essential roles. The aim of this study was to discover the efficacy of the antibody to a key immune cytokine IL-23 (anti-IL-23) for the therapy of cerebral ischemia-reperfusion injury. We established the cerebral ischemia-reperfusion injury model by middle cerebral artery occlusion (MCAO). Anti-IL-23 injection attenuated lesions indicated by histology study. RT-PCR and Western blot were employed to detect the mRNA and protein expression of JAK2 and STAT3 after anti-IL-23 treatment. ELISA was utilized to measure the levels of MDA (malondialdehyde) and superoxide dismutase (SOD). Moreover, curcumin and IL-6 were implicated in the endogenous intervention of IL-23 signaling in vivo. Our data demonstrated that the treatment of anti-IL-23 might transcriptionally activate the classic immune pathway in the brain. Anti-IL-23 augmented phosphorylation levels of both JAK2 and STAT3, suggesting the amplification signaling of JAK/STAT after exogenous IL-23 intervention. Anti-IL-23 reduced ROS molecules of STAT downstream in the serum and brain. It also alleviated the injury by bringing down levels of MDA and SOD in the serum. JAK2 inhibitor could abolish the effect of anti-IL-23 whereas JAK3 ameliorated the injury. The combination of anti-IL-23 and JAK3i could reduce infarct volume more effectively. In summary, this study indicated that anti-IL-23 had protective effects against cerebral ischemia-reperfusion injury by targeting the immune specific JAK2-STAT3 in JAK/STAT pathway.

Are biologics combined with methotrexate better than biologics monotherapy in psoriasis and psoriatic arthritis: A meta-analysis of randomized controlled trials

To investigate if the combination of biologics with methotrexate (MTX) would have better performance than biological monotherapy in clinical efficiency and safety for the treatment of psoriasis and psoriatic arthritis (PsA)， a systematic review of randomized controlled trials (RCTs) searched from the Pubmed, Cochrane Library, and Embase was conducted. Psoriasis Area and Severity Index (PASI) responses (including PASI 50, 75, and 90), and proportion of patients with Physician's Global Assessment Scale (sPGA) scored 0 or 1, were used for psoriasis assessment. The American College of Rheumatology (ACR)20/50/70 responder indices were used to assess the efficiency for treating PsA. The incidences of adverse events and antidrug antibodies' development were also recorded. A total of 15 studies with 4221 patients were included in this study. Three of the 15 RCTs were categorized as low risk of bias, nine studies as unclear, and three as high. Significant greater improvement in the combination group than monotherapy group for psoriasis was observed at week 12, week 24, and week 48, with no increased risk of severe adverse events and drug withdrawals due to adverse events. There was no significant difference in the comparison of clinical efficiency for the treatment of PsA at week 24. In conclusion, biologics plus MTX made better performance on improving the clinical efficiency for the treatment of psoriasis when compared with biologic monotherapy, without a difference in tolerability. However, this combination cannot improve the clinical efficiency of PsA treatment and more studies are warranted to elucidate relevant problems.

Role of the IL-23/IL-17 Pathway in Rheumatic Diseases: An Overview

Interleukin-23 (IL-23) is a pro-inflammatory cytokine composed of two subunits, IL-23A (p19) and IL-12/23B (p40), the latter shared with Interleukin-12 (IL-12). IL-23 is mainly produced by macrophages and dendritic cells, in response to exogenous or endogenous signals, and drives the differentiation and activation of T helper 17 (Th17) cells with subsequent production of IL-17A, IL-17F, IL-6, IL-22, and tumor necrosis factor α (TNF-α). Although IL-23 plays a pivotal role in the protective immune response to bacterial and fungal infections, its dysregulation has been shown to exacerbate chronic immune-mediated inflammation. Well-established experimental data support the concept that IL-23/IL-17 axis activation contributes to the development of several inflammatory diseases, such as PsA, Psoriasis, Psoriatic Arthritis; AS, Ankylosing Spondylitis; IBD, Inflammatory Bowel Disease; RA, Rheumatoid Arthritis; SS, Sjogren Syndrome; MS, Multiple Sclerosis. As a result, emerging clinical studies have focused on the blockade of this pathogenic axis as a promising therapeutic target in several autoimmune disorders; nevertheless, a greater understanding of its contribution still requires further investigation. This review aims to elucidate the most recent studies and literature data on the pathogenetic role of IL-23 and Th17 cells in inflammatory rheumatic diseases.

Broad proteomic screen reveals shared serum proteomic signature in patients with psoriatic arthritis and psoriasis without arthritis

OBJECTIVE

To identify novel serum proteins involved in the pathogenesis of PsA as compared with healthy controls, psoriasis (Pso) and AS, and to explore which proteins best correlated to major clinical features of the disease.

METHODS

A high-throughput serum biomarker platform (Olink) was used to assess the level of 951 unique proteins in serum of patients with PsA (n = 20), Pso (n = 18) and AS (n = 19), as well as healthy controls (HC, n = 20). Pso and PsA were matched for Psoriasis Area and Severity Index (PASI) and other clinical parameters.

RESULTS

We found 68 differentially expressed proteins (DEPs) in PsA as compared with HC. Of those DEPs, 48 proteins (71%) were also dysregulated in Pso and/or AS. Strikingly, there were no DEPs when comparing PsA with Pso directly. On the contrary, hierarchical cluster analysis and multidimensional scaling revealed that HC clustered distinctly from all patients, and that PsA and Pso grouped together. The number of swollen joints had the strongest positive correlation to ICAM-1 (r = 0.81, P < 0.001) and CCL18 (0.76, P < 0.001). PASI score was best correlated to PI3 (r = 0.54, P < 0.001) and IL-17 receptor A (r = -0.51, P < 0.01). There were more proteins correlated to PASI score when analysing Pso and PsA patients separately, as compared with analysing Pso and PsA patients pooled together.

CONCLUSION

PsA and Pso patients share a serum proteomic signature, which supports the concept of a single psoriatic spectrum of disease. Future studies should target skin and synovial tissues to uncover differences in local factors driving arthritis development in Pso.

Ixekizumab treatment of biologic-naïve patients with active psoriatic arthritis: 3-year results from a phase III clinical trial (SPIRIT-P1)

OBJECTIVE

The aim was to assess the safety and efficacy of up to 156 weeks of ixekizumab (an IL-17A antagonist) treatment in PsA patients.

METHODS

In a phase III study, patients naïve to biologic treatment were randomized to placebo, adalimumab 40 mg every 2 weeks (ADA; active reference) or ixekizumab 80 mg every 2 weeks (IXEQ2W) or every 4 weeks (IXEQ4W) after an initial dose of 160 mg. At week 24 (week 16 for inadequate responders), ADA (after 8-week washout) and placebo patients were re-randomized to IXEQ2W or IXEQ4W. Outcomes were evaluated using a modified non-responder imputation [linear extrapolation for radiographic progression (modified total Sharp score = 0)] during extended treatment until week 156.

RESULTS

Of 417 patients, 381 entered the extension, and 243 of 381 (63.8%) completed the 156-week study. Incidence rates of treatment-emergent and serious adverse events, respectively, were 38.0 and 5.2 with IXEQ2W (n = 189) and 38.1 and 8.0 with IXEQ4W (n = 197). One death occurred (IXEQ4W). With IXEQ2W and IXEQ4W, respectively, the response rates persisted to week 156 as measured by the ACR response ≥20% (62.5 and 69.8%), ≥50% (56.1 and 51.8%) and ≥70% (43.8 and 33.4%), psoriasis area and severity index (PASI) 75 (69.1 and 63.5%), PASI 90 (64.5 and 51.2%) and PASI 100 (60.5 and 43.6%). Inhibition of radiographic progression also persisted to week 156 in 61% of IXEQ2W and 71% of IXEQ4W patients.

CONCLUSION

In this 156-week study of ixekizumab, the safety profile remained consistent with previous reports, and improvements in signs and symptoms of PsA were observed, including persistent low rates of radiographic progression.

TRIAL REGISTRATION

ClinicalTrials.gov, http://clinicaltrials.gov, NCT01695239, EudraCT 2011-002326-49.

Role of CYR61 in psoriatic lesional and perilesional skin: A clinical and immunohistochemical study

BACKGROUND

Psoriasis is considered as an immune-mediated disorder with significant epidermal hyperplasia and inflammation. Cysteine-rich angiogenic inducer 61 (CYR61), known as CCN family member 1 (CCN1), plays an important role in cell proliferation and neovascularization which may trigger psoriasis development.

AIMS

This study aimed to assess the immunostaining of CYR61 in psoriatic skin (lesional and perilesional) compared to control skin.

PATIENTS/METHODS

This is a case-control study. The Psoriasis Area and Severity Index (PASI) was used to evaluate disease severity. A punch biopsy was taken from psoriatic skin lesions (30), perilesional (30) skin, and matched site of controls (20). The pathological and immunostaining assessments of CYR61 were conducted.

RESULTS

There was a significant gradual progressive overexpression of CYR61 in keratinocytes from control skin to perilesional and lesional psoriatic skin (P = .00). Moreover, lesional psoriatic skin showed overexpression of CYR61 in inflammatory cells in the dermis than controls. CYR61 expression (lesional epidermis) revealed a significant positive correlation with the PASI score (r = .63; P = .00). There was a significant relationship between intensity and H-core of CYR61 in the lesional psoriatic epidermis with joint affection.

CONCLUSION

CYR61 may trigger epidermal hyperplasia and potentiate inflammatory infiltration in psoriasis vulgaris patients, and therapies targeting CYR61 may be effective in the management of psoriasis vulgaris.

Bone Mineral Density, Osteoporosis, and Fracture Risk in Adult Patients with Psoriasis or Psoriatic Arthritis: A Systematic Review and Meta-Analysis of Observational Studies

INTRODUCTION

Awareness of psoriasis-related comorbidities has been established in the current guidelines; however, evidence regarding the association of bone density or bone fragility with psoriatic disease remains inconclusive.

METHODS

We conducted a systematic review and meta-analysis to assess bone mineral density and the risk of osteoporosis and fractures in patients with psoriatic disease, including those with cutaneous psoriasis and psoriatic arthritis. We searched electronic databases for published observational studies. A meta-analysis was performed using the random-effect model. Pooled estimates and their confidence intervals (CIs) were calculated. Small-study effects were examined using the Doi plot and Luis Furuya-Kanamori index.

RESULTS

The analysis of the standardized mean difference in the absolute value of bone mineral density at different measuring sites (lumbar spine, femoral neck, and total hip) revealed no significant difference between patients with psoriatic disease and non-psoriatic controls. The pooled results of the adjusted odds ratios (ORs) demonstrated no increased risk of osteoporosis in patients with psoriatic disease. Notably, patients with psoriatic disease had a higher OR of developing bone fractures (adjusted OR: 1.09; 95% CI: 1.06 to 1.12; I²: 0%).

CONCLUSION

Patients with psoriatic disease may be more likely to develop fractures compared with non-psoriatic controls. This higher risk for fracture may not necessarily be associated with lower bone mineral density nor a higher risk for osteoporosis.

IL-17 promotes proliferation, inflammation and inhibits apoptosis of HaCaT cells via interacting with the TRAF3 interacting protein 2

The present study aimed to investigate the effects of interleukin-17 (IL-17) on the function of keratinocytes and to further investigate its associated mechanism. Human immortalized epidermal cells (HaCaT) were divided into sham control group (Sham), TRAF3 interacting protein 2 (TRAF3IP2)-knockdown with lentivirus group (si-TRAF3IP2), sham control+IL-17 group (Sham+IL-17) and TRAF3IP2-knockdown with lentivirus+IL-17 group (si-TRAF3IP2+IL-17). MTT and flow cytometry assays demonstrated that IL-17 promoted proliferation and inhibited apoptosis of HaCaT cells, while this effect was reversed following knockdown of TRAF3IP2 with lentiviral vectors. In addition, a marked increase in the levels of IL-6, IL-8, IL-23, TNF-α and VEGF was observed in the Sham+IL-17 group compared with that noted in the Sham group (P<0.05). Furthermore, reverse transcription-quantitative polymerase chain reaction and western blotting indicated that the mRNA and protein expression levels of caspase-3 in the si-TRAF3IP2+IL-17 group were significantly increased compared with those of the Sham+IL-17 group (P<0.05). Taken together, the results indicated that IL-17 promoted proliferation and inflammation and inhibited apoptosis of HaCaT cells by interacting with the TRAF3IP2 adaptor protein, while knockdown of the expression of TRAF3IP2 reduced the effects of IL-17 in HaCaT cells.

Crohn's disease exacerbated by IL-17 inhibitors in patients with psoriasis: a case report

BACKGROUND

Previous studied revealed that psoriasis and Inflammatory bowel disease (IBD) have highly overlapping epidemiological characteristics, genetic susceptibility loci, disease risk factors, immune mechanisms, and comorbidities. More and more biologics have been used to treat psoriasis and IBD. Interleukin (IL)-17 inhibitors played an important role in the treatment of psoriasis, but induced and aggravated inflammatory bowel disease in some patients. IL-23 inhibitors have shown to be effective to both psoriasis and CD.

CASE PRESENTATION

Forty-one year old Chinese male patient who came to the hospital for psoriasis, developed severe gastrointestinal symptoms after using an IL-17 inhibitor, and was diagnosed with Crohn's disease (CD). The patient eventually used an IL-23 inhibitor to relieve both psoriasis and CD.

CONCLUSION

IBD patients and psoriasis patients have increased probability of suffering from the other disease. The case that patients had suffered from psoriasis and CD before the use of IL-17 inhibitor is quite rare. This case suggests that physicians need to be careful when treating patients with psoriasis and CD with biologics, and it is necessary to evaluate the gastrointestinal tract.

Autoantibodies against specific nuclear antigens are present in psoriatic disease and are diminished by secukinumab

Anti-nuclear antibodies (ANA) are frequently detected in patients with psoriasis (Ps) and psoriatic arthritis (PsA), but their target autoantigens remain unknown. We assessed antibody (ab) reactivity against 23 known nuclear antigens in patients with Ps and PsA and assess the effects of secukinumab (anti-IL17A) treatment on ANA levels. A total of 201 patients, 101 with Ps and 100 with PsA, and 50 ANA-negative healthy controls (HCs) were tested for ANAs by a line immunoassay testing reactivity to 23 nuclear antigens. Ab reactivity to at least 1 antigen was found in 20.4% psoriatic disease patients (25.7% Ps and 15% PsA) compared to 8% HCs (p = ns), the most frequent being against dense fine speckled 70 (DFS70) (6.5%). In Ps and PsA patients with secukinumab-induced remission, anti-DFS70 and other antigen-specific autoantibodies were diminished over time. No decline was noted for IgG abs against antigens from pathogens such as cytomegalovirus, Epstein-Barr virus and Helicobacter pylori. Autoantibody decrease was associated with significant reduction of plasmablasts, follicular B and follicular T cells. In conclusion, one third of antigen-specific ANA patients with psoriatic disease recognize DFS70. Secukinumab decreases nuclear antigen autoreactivity, plasmablasts, follicular B and follicular T cells, highlighting a new mechanism of its action.

The Role of Gut Microbiome in Psoriasis: Oral Administration of Staphylococcus aureus and Streptococcus danieliae Exacerbates Skin Inflammation of Imiquimod-Induced Psoriasis-Like Dermatitis

Psoriasis is one of the common chronic inflammatory skin diseases in which inflammatory cytokines such as IL-17 and TNF-α play critical roles. Skin microbiome of psoriasis patients is reported to have elevated Staphylococcus and Streptococcus genus. There are controversial reports about gut microbiome of psoriasis patients, and whether the diversity of bacteria in genus level is decreased or not is still unclear. Moreover, it is not yet known if these gut bacteria would be the cause of the inflammation or the result of the inflammation. We analyzed the gut microbiome of the inflammatory skin model mouse (keratinocyte-specific caspase-1 transgenic (Kcasp1Tg) mouse), by analyzing the 16S rRNA gene. Staphylocuccus aureus and Streptococcus danieliae were abundant in Kcasp1Tg mouse fecal microbiome. These dominant bacteria as well as recessive control bacteria were orally administrated to antibiotic-treated wild type mice, and set up imiquimod-induced psoriasis-like skin inflammation model. The skin inflammation including ear thickness and histopathological findings was analyzed. The exacerbated skin lesions with the elevated levels of TNF-α, IL-17A, IL-17F, and IL-22 were observed in Staphylocuccus aureus and Streptococcus danieliae administrated groups. Our finding suggests that there is affinity between skin inflammation severity and certain gut bacteria leading to a vicious cycle: skin inflammation populates certain gut bacteria which itself worsens the skin inflammation. This is the first report on Staphylocuccus aureus and Streptococcuus danieliae effects in vivo. Not only treating the skin lesion but also treating the gut microbiome could be the future key treatment for inflammatory skin disease such as psoriasis.

Recent genetic advances in innate immunity of psoriatic arthritis

Psoriatic arthritis (PsA) is a heterogeneous disease that affects multiple organ systems including the peripheral and axial joints, entheses and nails. PsA is associated with significant comorbidities including cardiovascular, metabolic, and psychiatric diseases. The pathogenesis of PsA is complex and involves genetic, immunologic and environmental factors. Recent evidence suggests the heritability for PsA to be stronger and distinct from that of PsC. Prominent genes identified via GWAS for PsA include HLA-B/C, HLAB, IL12B, IL23R, TNP1, TRAF3IP3, and REL. We review the genetics of psoriatic arthritis and discuss the role of the innate immune system as important in the pathogenesis of PsA by focusing on key signaling pathways and cellular makeup. Understanding the candidate genes identified in PsA highlights pathways of critical importance to the pathogenesis of psoriatic disease including the key role of the innate immune response, mediated through IL-23/IL-17 axis, RANK and NFκB signaling pathways.

Association of cytokine patterns and clinical/laboratory parameters, medication and periodontal burden in patients with rheumatoid arthritis (RA)

To evaluate serum levels of the following cytokines in rheumatoid arthritis subjects with periodontal disease: Interleukin-6, -10, -17, and -23. Patients with rheumatoid arthritis frequently suffer from periodontal disease. Both diseases partly result from a dysregulated immune response. The current study aimed to quantify Interleukin-6, -10, -17, and -23 levels in rheumatoid arthritis. It should be investigated if the periodontal disease would have additional modifying effects. A total of 157 patients were included. Serum levels of IL-6, -10, -17, and -23 were measured by ELISA. Serum IL-10 increased with longer duration of morning stiffness and with higher rheumatoid factor and anti-cyclic citrullinated peptide titres. IL-10 was also elevated with longer duration of prednisolone (< 5 mg daily) and leflunomide therapy. Subjects with lower erythrocyte sedimentation rate/longer leflunomide therapy displayed more missing teeth/more clinical attachment loss. IL-17 was higher in subjects with fewer missing teeth if the following criteria were fulfilled: shorter prednisolone (< 5 mg) and methotrexate therapy, more swollen joints, longer morning stiffness. IL-23 finally was increased in subjects with higher rheumatoid factor and in those with higher periodontal probing depth/clinical attachment loss in the following situations: lower rheumatoid factor and shorter leflunomide therapy. Subjects suffering from dental/periodontal burden show an aberrant systemic cytokine availability of serum IL-6, IL-10, IL-17 and IL-23 related to disease activity and medication. This examination underlines the complexity of potential interactions between disease activity and medication related to periodontal burden.

Apremilast increases IL-10-producing regulatory B cells and decreases proinflammatory T cells and innate cells in psoriatic arthritis and psoriasis

OBJECTIVES

Psoriatic arthritis (PsA) and psoriasis are immune-mediated inflammatory diseases sharing common immunological mechanisms. Regulatory B cells (Breg cells) producing IL-10 (B10 cells), a critical anti-inflammatory B-cell subset, were found to be decreased in both PsA and psoriasis. Apremilast, a phosphodiesterase-4(PDE4) inhibitor, increases IL-10 and therefore, we examined the effect of apremilast on Breg cells.

METHODS

Fifty patients, including 20 with PsA and 30 with psoriasis, were included in the study. The effect of apremilast on Breg cells at 3, 6 and 12 months post-treatment, was examined by flow cytometry in ODN2006 (TLR9)-stimulated peripheral blood mononuclear cells and magnetically-isolated cells. Th1 cells, Th17 cells and NKT were also measured.

RESULTS

Ex vivo stimulated cell analysis identified that post-apremilast (IL-10+CD19+) B10 cells were increased in all PsA and psoriasis patients and correlated with psoriatic skin and joint clinical improvement. Apremilast decreased IFNγ(+) T and NKT cells and IL-17(+)NKT cells. B10 cells also inversely correlated with Th1 cells, and IFNγ(+)NKT cells.

CONCLUSION

These results suggest that Breg cells are a major target of apremilast in PsA and psoriasis and that apremilast-induced increase of Breg cells is associated with a decrease of Th1 cells, IFNγ-producing NKT cells and IL-17-producing NKT cells.

Biologic therapy and spinal radiographic progression in patients with axial spondyloarthritis: A structured literature review

We aimed to perform a structured literature review of spinal radiographic progression, as assessed by the modified Stoke Ankylosing Spondylitis Spine Score (mSASSS), in patients with ankylosing spondylitis (AS) or nonradiographic axial spondyloarthritis (nr-axSpA) treated with biologic therapy. Searches were limited to English language manuscripts published in the 11 years prior to 9 July 2019. Randomized controlled trials, open-label extensions (OLEs) and observational studies reporting mSASSS progression in patients with AS or nr-axSpA treated with biologics were eligible for inclusion. Bias was assessed using the methodological index for nonrandomized studies (MINORS) tool. Among the 322 studies identified in the literature search, 23 (11 OLEs and 12 cohort studies) met the eligibility criteria and were selected for inclusion. Most studies reported mSASSS progression in patients with AS receiving tumor necrosis factor inhibitor (TNFi) treatment. One study reported mSASSS progression in patients with AS treated with secukinumab, an interleukin-17A inhibitor. The mean (range) MINORS score was 11.3 (7-15) for the 15 noncomparative studies and 15 (12-22) for the 8 comparative studies. Although results of the individual studies were variable, mSASSS progression in patients with AS was generally minimal and slow with long-term TNFi therapy. Moreover, odds ratios for the likelihood of mSASSS progression with/without TNFi favoured TNFi therapy in several of the cohort studies. The rate of mSASSS progression following continuous secukinumab treatment was low and remained stable over 4 years. Of two studies reporting progression in patients with nr-axSpA treated with TNFis, one showed no mSASSS progression; however, the lack of control limited comparative conclusions.

Exposure-response analyses demonstrate no evidence of interleukin 17A contribution to efficacy of ABT-122 in rheumatoid or psoriatic arthritis

Objectives

ABT-122 is a dual-variable-domain immunoglobulin that neutralizes both TNF-α and IL-17A. The objective of this work was to characterize exposure-response relationships for ABT-122 relative to adalimumab (TNF-α inhibitor) using ABT-122 phase 2 trials in patients with RA or PsA.

Methods

Patients received subcutaneous doses of ABT-122 ranging from 60 mg every other week (EOW) to 240 mg every week, adalimumab 40 mg EOW, or placebo (PsA patients only) for 12 weeks. Relationships between ABT-122 or adalimumab serum concentrations and time course of ACR20, ACR50 and ACR70 and PASI50, PASI75 and PASI90 responses were characterized using a non-linear mixed-effects Markov modelling approach.

Results

A total of 221 RA patients and 240 PsA patients were included in the analyses. At comparable molar exposures, there was no differentiation of efficacy between ABT-122 and adalimumab and there were no consistent differences between ABT-122 and adalimumab in the potency estimates for different efficacy endpoints based on the Markov models. Plateau of ABT-122 efficacy was achieved at exposures associated with the 120 mg EOW dose in patients with RA, which were comparable to molar exposures of adalimumab 40 mg EOW, and at the lowest dose of 120 mg every week in patients with PsA.

Conclusion

The exposure-response relationships for ABT-122 were not distinguishably different from those of adalimumab in patients with RA or PsA. Overall, there was no clear evidence that inhibition of the IL-17 pathway provided incremental benefit in the presence of TNF-α inhibition.

Trial registration

ClinicalTrials.gov, NCT02433340, NCT02349451.

Pharmacodynamics OF TNF α inhibitors for the treatment of psoriasis

Introduction: The treatment of psoriasis with conventional topical therapies and disease-modifying anti-rheumatic drugs (DMARDs) is often linked to unsatisfactory outcomes and the risk of serious adverse events. Over the last decades, research advances in understanding the role of tumor necrosis factor alpha (TNF α) and other cytokines in the pathogenesis of psoriasis have driven the introduction of biologic agents targeting specific immune mediators in everyday clinical practice. TNF α inhibitors are a consolidated treatment option for patients with moderate-to-severe disease with remarkable efficacy and a reassuring safety profile.Areas covered: The PubMed database was searched using combinations of the following keywords: psoriasis, TNF α inhibitors, biologic therapy, pharmacodynamics, adalimumab, etanercept, infliximab, certolizumab pegol, golimumab, adverse effects. The aim of this review is to describe the pharmacodynamic profile of anti-TNF α inhibitors, currently approved by the European Medicines Agency (EMA) for the treatment of psoriasis, focusing on related clinical implications, also in comparison to the new generation biological therapies targeting the interleukin 23/interleukin 17 axis.Expert opinion: Pharmacodynamics of TNF α inhibitors should be fully considered in planning patient's therapy strategies, especially in case of secondary failures, poor adherence to treatment, instable psoriasis, high risk of infection, pregnant or lactating women, metabolic comorbidities, coexistence of other immune-mediated inflammatory diseases.

Evaluation of expression pattern of selected genes associated with IL12/23 signaling paths in psoriatic patients during cyclosporine A therapy

Molecular analysis is key to a better understanding of drug resistance during therapy. The aim of this study was to evaluate changes in the expression of tumor necrosis factor α (TNF-α), interleukin (IL)-IL12A, IL12B, IL23A, interferon gamma (IFN-γ) in psoriatic patients during 84 days of treatment and TNF-α on the protein level. The study group consisted of 32 psoriatic patients during cyclosporine A therapy. The molecular analysis was made by using real-time reverse transcription polymerase chain assay (RTqPCR) and MALDI ToF mass spectroscopy three times: after 0, 42, 84 days of treatment. Statistically significant differences (p < .05) in transcriptional activity were observed for genes: TNF-α (0 vs. 42nd days p = .006; 0 vs. 84th days p = .005), IL23A (0 vs. 42nd days p = .041), IFN-γ (0 vs. 42th days p = .040; 0 vs. 84th days p = .041), IL17 (0 vs. 42nd p = .000003 0 vs. 84th p = .001650), IL12A (0 vs. 42nd p = .0047 vs. 84th p = .0063). The expression of TNF-α was downregulated during therapy, IL23A was upregulated during CsA treatment, while the expression of IFN-γ and IL17 were higher after 42 days and lower after 84 days compared to 0 days of CsA treatment. It seems that TNF-α, IL12A, IL23A, IFN-γ, and IL17 can be useful complementary molecular markers to assess the efficacy of psoriasis treatment.

Serum IFI16 and anti-IFI16 antibodies in psoriatic arthritis

Nuclear interferon-inducible protein 16 (IFI16) and anti-IFI16 antibodies have been detected in subjects with several rheumatic diseases, often correlating with disease severity, and in this study we investigated their prevalence and clinical associations in psoriatic arthritis (PsA) compared to psoriasis (Pso). We tested sera and synovial fluids of patients with PsA for IFI16 protein levels by capture enzyme-linked immunosorbent assay (ELISA) and for anti-IFI16 immunoglobulin (Ig)G and IgA by ELISA, protein radio-immunoprecipitation and immunoprecipitation-Western blot of IgG. Sera from patients with Pso and healthy subjects were used as controls, and in a subgroup of patients with PsA we also studied sera after treatment with etanercept. IFI16 was detectable in the sera of 66% of patients with Pso, 46% with PsA and 19% of controls. Among PsA cases, 51% of IFI16-positive cases had elevated levels of C-reactive protein (CRP) compared to 31% of patients with undetectable IFI16. Anti-IFI16 of both IgG and IgA isoforms were detected with significantly higher frequency in PsA and Pso compared to healthy controls, with higher IgG titres in patients with elevated C-reactive protein (CRP) (P = 0·015). Immunoprecipitation confirmed the presence of anti-IFI16 IgG antibodies and these preferentially recognized epitopes outside the N-terminus of the protein. Lastly, IFI16 was detected in one of seven and anti-IFI16 in three of seven synovial fluids from patients with PsA. Therefore, IFI16 and anti-IFI16 are detectable in serum and synovial fluid of PsA patients, especially in cases of elevated CRP.