Paradoxical gastrointestinal effects of interleukin-17 blockers

Intestinal Epithelial Tight Junction Barrier Regulation by Novel Pathways

Intestinal epithelial tight junctions (TJs), a dynamically regulated barrier structure composed of occludin and claudin family of proteins, mediate the interaction between the host and the external environment by allowing selective paracellular permeability between the luminal and serosal compartments of the intestine. TJs are highly dynamic structures and can undergo constant architectural remodeling in response to various external stimuli. This is mediated by an array of intracellular signaling pathways that alters TJ protein expression and localization. Dysfunctional regulation of TJ components compromising the barrier homeostasis is an important pathogenic factor for pathological conditions including inflammatory bowel disease (IBD). Previous studies have elucidated the significance of TJ barrier integrity and key regulatory mechanisms through various in vitro and in vivo models. In recent years, considerable efforts have been made to understand the crosstalk between various signaling pathways that regulate formation and disassembly of TJs. This review provides a comprehensive view on the novel mechanisms that regulate the TJ barrier and permeability. We discuss the latest evidence on how ion transport, cytoskeleton and extracellular matrix proteins, signaling pathways, and cell survival mechanism of autophagy regulate intestinal TJ barrier function. We also provide a perspective on the context-specific outcomes of the TJ barrier modulation. The knowledge on the diverse TJ barrier regulatory mechanisms will provide further insights on the relevance of the TJ barrier defects and potential target molecules/pathways for IBD.

C/EBPδ Mediates Immunity to Renal Autoinflammatory Disorders in a Stage-specific Manner

Kidney disease represents a major medical and economic burden for which improved treatments are urgently needed. Emerging data have implicated Th17 cells and IL-17 signaling in the underlying pathogenesis of autoantibody-induced glomerulonephritis (AGN). However, the downstream transduction pathways mediated by IL-17 in autoimmunity are not well defined. In this article, we show that CCAAT/enhancer-binding protein (C/EBP) δ is elevated in kidney biopsies from multiple manifestations of human AGN. C/EBPδ is similarly upregulated in a mouse model of anti-glomerular basement membrane protein-mediated kidney disease, and Cebpd-/- mice were fully refractory to disease. Although C/EBPδ is expressed in a variety of cell types, C/EBPδ was required only in the radioresistant compartment to drive GN pathology. C/EBPδ induced expression of several IL-17-induced kidney injury markers and cytokines implicated in disease, including Il6 and Lcn2. Because mouse AGN models do not progress to fibrosis, we employed a nephrotoxic injury model using aristolochic acid I to assess the contribution of the IL-17-C/EBPδ pathway to renal fibrotic events. Surprisingly, deficiency of either C/EBPδ or the IL-17 receptor caused kidney fibrosis to be enhanced. Thus, C/EBPδ and IL-17 play divergent and apparently stage-specific roles in the pathogenesis of kidney disease.

Mesenchymal stromal cells restrain the Th17 cell response via L-amino-acid oxidase within lymph nodes

Mesenchymal stromal/stem cells (MSC) have emerged as a promising therapeutic avenue for treating autoimmune diseases, eliciting considerable interest and discussion regarding their underlying mechanisms. This study revealed the distinctive ability of human umbilical cord MSC to aggregate within the lymph nodes of mice afflicted with autoimmune diseases, but this phenomenon was not observed in healthy mice. The specific distribution is driven by the heightened expression of the CCL21-CCR7 axis in mice with autoimmune diseases, facilitating the targeted homing of MSC to the lymph nodes. Within the lymph nodes, MSC exhibit a remarkable capacity to modulate Th17 cell function, exerting a pronounced anti-inflammatory effect. Transplanted MSC stimulates the secretion of L-amino-acid oxidase (LAAO), a response triggered by elevated levels of tumor necrosis factor-α (TNF-α) in mice with autoimmune diseases through the NF-κB pathway. The presence of LAAO is indispensable for the efficacy of MSC, as it significantly contributes to the inhibition of Th17 cells. Furthermore, LAAO-derived indole-3-pyruvic acid (I3P) serves as a potent suppressor of Th17 cells by activating the aryl hydrocarbon receptor (AHR) pathway. These findings advance our understanding of the global immunomodulatory effects exerted by MSC, providing valuable information for optimizing therapeutic outcomes.

IL-17 inhibitors in axial spondyloarthritis. An overview

INTRODUCTION

The therapeutic armamentarium for spondyloarthritis has expanded considerably in recent years, and there is growing evidence to support the increasing use of IL-17 inhibitors (IL-17i) in axial spondyloarthritis (axSpA).

AREAS COVERED

This literature review provides an update on the role of IL-17 in the pathogenesis of axSpA, efficacy and safety from clinical trials and real-life studies on the use of IL17i in axSpA. We also review the impact of extra-musculoskeletal manifestations on the decision to treat with IL17i and the efficacy of IL17i on structural progression.

EXPERT OPINION

There are still some unanswered questions concerning the use of IL-17i in axSpA in clinical practice such as their respective place in the management of axSpA compared to TNFα inhibitors (TNFi). Their main differences rely on their specific efficacy in extra-articular manifestations such as psoriasis, uveitis, and inflammatory bowel diseases leading to the choice of the best treatment in a given patient. Regarding their real impact on structural progression, the rate of progression under IL-17i appears to be low and presumably similar to TNFi. One final question is the advantage of blocking the two IL-17 isoforms A and F compared to the single inhibition of IL-17A.

Duodenal transcriptomics demonstrates signatures of tissue inflammation and immune cell infiltration in children with environmental enteric dysfunction across global centers

BACKGROUND

Environmental enteric dysfunction (EED) is an inflammatory condition of the small intestine that is prevalent in children residing in low- and middle-income countries. EED is accompanied by profound histopathologic changes in the small bowel, loss of absorptive capacity, increased intestinal permeability, increased microbial translocation, and nutrient loss.

OBJECTIVES

We sought to identify dysregulated genes and pathways that might underlie pediatric EED.

METHODS

RNA-sequencing libraries were generated from endoscopically obtained duodenal tissue from undernourished children with EED from 3 prospective cohorts of children with EED. The EED transcriptome was defined in comparison to North American children without EED. Weighted gene coexpression network analysis (WGCNA) was tested for gene modules associated with EED and its histologic features.

RESULTS

The 1784 upregulated genes in EED were highly enriched for immune and inflammatory processes, including IL-17 and JAK-STAT signaling, and cytokine-cytokine receptor interactions. The 1388 downregulated genes included genes corresponding to xenobiotic metabolism, detoxification, and antioxidant capacities. A gene coexpression module enriched for antimicrobial responses and chemokine activity was significantly associated with villous blunting, goblet cell depletion, and overall histologic severity of EED.

CONCLUSIONS

The transcriptome signatures of EED include specific innate and adaptive immune responses that are consistently elevated across study centers, coupled with reduced detoxification and antioxidant capacities. These data may have implications for targeted interventions to improve EED outcomes.

Multiplex spatial omics reveals changes in immune-epithelial crosstalk during inflammation and dysplasia development in chronic IBD patients

Patients with long-standing inflammatory bowel disease (IBD) face an increased risk of developing colitis-associated cancer (CAC). Although IBD-induced prolonged inflammation seems to be involved in CAC pathogenesis, the specific molecular changes that contribute remain unknown. Here, we applied digital spatial RNA profiling, RNAscope, and imaging mass cytometry to examine paired uninflamed, inflamed, and early dysplastic mucosa of patients with IBD. We observed robust type 3 (IL-17) responses during inflammation, accompanied by elevated JAK-STAT signaling and phosphorylated STAT3 (P-STAT3) levels, with both inflamed and dysplastic mucosa displaying immune cell activation. Higher stromal P-STAT3 was detected in uninflamed and inflamed mucosa of patients who eventually developed dysplasia. CD8a+ T cells did not infiltrate inflamed or dysplastic epithelial regions in these patients, while control patients showed elevated CD8a in inflamed mucosa. Our study reveals distinct inflammatory patterns throughout CAC development, marked by an activated IL-17 pathway, engaged STAT3, and diminished cytotoxic T cell infiltration.

A Systematic Overview of Contraindications and Special Warnings for Biologic and Targeted Synthetic Disease Modifying Antirheumatic Drugs: Establishing a Framework to Create a "Safety Checklist"

BACKGROUND/AIM

The purpose of this review is to provide an overview of the contraindications, special warnings, and boxed warnings with the aim to establish a framework to create a prescription safety checklist for a class of drugs or disease indication. This study covers biologic disease modifying antirheumatic drugs (bDMARDs) and targeted synthetic DMARDs (tsDMARDs).

METHODS

We identified contraindications, boxed warnings, and special warnings provided by the European Medicines Agency (EMA) and the US Food and Drug Administration (FDA). The study included b/tsDMARDs approved for treating rheumatoid arthritis (RA), psoriatic arthritis (PsA), axial spondyloarthritis (SpA), and juvenile idiopathic arthritis (JIA) within the drug-classes anti-CD20, tumor necrosis factor inhibitors (TNFi), interleukin-1 inhibitors (IL-1i), cytotoxic T-lymphocyte-associated protein (CTLA) 4, interleukin-12/23 inhibitors (IL-12/23i), interleukin 6 receptor inhibitors (IL-6Ri), Janus kinase inhibitors (JAKi), phosphodiesterase 4 inhibitors (PDE4i), interleukin-17 inhibitors (IL-17i), and interleukin-23 inhibitors (IL-23i).

RESULTS

All drug classes, except PDE4i, had contraindications and/or warnings related to infections, including tuberculosis. A warning about herpes zoster was listed for anti-CD20, IL-1i, IL-6Ri, and JAKi, while a warning about hepatitis reactivation was listed for anti-CD20, TNFi, IL-1i, CTLA4-Ig, IL-6Ri, and JAKi. Malignancy risk was mentioned for all drug classes except PDE4i, IL-17i, and IL-23i. Other warnings included demyelinating disease (TNFi, CTLA4-Ig, and IL-6Ri), heart failure (anti-CD20 and TNFi), major adverse cardiac events (JAKi and IL-12/23) and venous thromboembolism (JAKi), hyperlipidemia (IL-6Ri and JAKi), liver impairment (TNFi, IL-1i, IL-6Ri, and JAKi), kidney impairment (IL-1i, JAKi, and PDE4i), inflammatory bowel disease (IL-17i), gastrointestinal perforation (IL-6Ri, JAKi), cytopenia (anti-CD20, TNFi, IL-1i, IL-6Ri, JAKi), and depression (PDE4i). Contraindications and warnings appeared to increase with the passage of time since the drug's approval.

CONCLUSION

This review provides an overview to establish the framework to create an easily accessible and actionable prescription safety checklist from individual medical product prescription information provided by regulatory medical authorities.

Psoriasis Comorbidities and Their Treatment Impact

Psoriasis, a systemic inflammatory disease classically presenting with cutaneous lesions, has significant involvement in other organ systems. This article explores the prevalence, clinical manifestations, screening mechanisms, and laboratory testing by which to evaluate these comorbidities. Treatment approach for these comorbidities must combine patient preference with established treatment algorithms while recognizing innovative therapeutics currently under development.

Sacroiliitis in inflammatory bowel disease

PURPOSE OF REVIEW

This review summarizes the recent evidence regarding the epidemiology of inflammatory bowel disease (IBD) associated sacroiliitis, including the prevalence, pathogenesis, role of imaging, and therapeutic challenges.

RECENT FINDINGS

Sacroiliitis is an underappreciated musculoskeletal manifestation of IBD, a chronic inflammatory condition of the gut affecting the younger population. Untreated sacroiliitis can lead to joint destruction and chronic pain, further adding to morbidity in IBD patients. Recent publications suggest sacroiliitis can be detected on abdominal imaging obtained in IBD patients to study bowel disease, but only a small fraction of these patients were seen by rheumatologists. Early detection of IBD-associated sacroiliitis could be achieved by utilization of clinical screening tools in IBD clinics, careful examination of existing computed tomography and MRI studies, and timely referral to rheumatologist for further evaluation and treatment. Current treatment approaches for IBD and sacroiliitis include several targeted biologic therapies, but IBD-associated sacroiliitis has limited options, as these therapies may not overlap in both conditions.

SUMMARY

With the advances in imaging, sacroiliitis is an increasingly recognized comorbidity in IBD patients. Future studies focusing on this unique patient population will expand our understanding of complex pathophysiology of IBD-associated sacroiliitis and lead to identification of novel targeted therapies for this condition.

Advancements in understanding the role of intestinal dysbacteriosis mediated mucosal immunity in IgA nephropathy

IgA nephropathy, presently recognized as the foremost primary glomerular disorder, emerges as a principal contributor to renal failure globally, with its pathogenesis yet to be fully elucidated. Extensive research has highlighted the critical role of gut microbiome in the onset and progression of IgA nephropathy, underscoring its importance in accurately delineating the disease's etiology. For example, gut microbiome dysbacteriosis can lead to the production of nephritogenic IgA1 antibodies, which form immune complexes that deposit in the kidneys, causing inflammation and damage. The gut microbiome, a source of numerous bioactive compounds, interacts with the host and plays a regulatory role in gut-immune axis modulation, earning it the moniker of the "second brain." Recent investigations have particularly emphasized a significant correlation between IgA nephropathy and gut microbiome dysbacteriosis. This article offers a detailed overview of the pathogenic mechanisms of IgA nephropathy, specifically focusing on elucidating how alterations in the gut microbiome are associated with anomalies in the intestinal mucosal system in IgA nephropathy. Additionally, it describes the possible influence of gut microbiome on recurrent IgA nephropathy following kidney transplantation. Furthermore, it compiles potential therapeutic interventions, offering both theoretical and practical foundations for the management of IgA nephropathy. Lastly, the challenges currently faced in the therapeutic approaches to IgA nephropathy are discussed.

IL-23 exerts dominant pathogenic functions in Crohn's disease-ileitis

Crohn's disease (CD), a main form of Inflammatory Bowel Disease (IBD) is a chronic inflammatory disorder, mainly affecting the ileum. Interleukin (IL)-12 and IL-23 are both targeted by Ustekinumab, a commonly used monoclonal antibody for IBD treatment. However, their specific roles in ileitis have not been extensively explored. Here, we utilized the TnfΔΑRE model of CD-ileitis to probe the functions of IL-12 and IL-23 by employing genetically deficient mice for their respective subunits. Our findings highlight that IL-23, rather than IL-12, plays a pivotal role in the progression of ileitis. IL-23 deficiency resulted in reduced immune cell infiltration in the ileum, and decreased expression of effector cytokines downstream of IL-23 signaling. Interestingly, expanding CD14+ neutrophils were highly expressing Il23a in the inflamed ileum. Furthermore, the deletion of IL-12 conferred modest additional protection only in the absence of IL-23, suggesting potential compensatory mechanisms between these cytokines. Furthermore, our study suggests that IL-23 may function independently of IL-17, as Il17a deletion exacerbated murine ileitis, consistent with clinical studies in human CD patients using anti-IL-17 inhibitors. This research underscores the significance of targeting IL-23 in CD-ileitis, while the concurrent targeting of both IL-12 and IL-23 should be also considered as an advantageous therapeutic approach.

Existing and Emerging Targeted Therapies in Juvenile Psoriatic Arthritis: Challenges and Unmet Needs

Juvenile psoriatic arthritis (JPsA) is a heterogeneous type of non-systemic chronic inflammatory arthritis affecting children and young people. This review focuses on highlighting challenges in harmonising recommendations for the use of available therapies in JPsA, according to its distinct clinical phenotypes, and explores the similarities and differences between the disease classification and management across age. We further explore the emerging therapeutic landscape, summarising the recently completed clinical trials in JPsA, and ongoing studies in both JPsA and adults with psoriatic arthritis, highlighting unmet needs and barriers for translational research in JPsA. The novel therapeutic agents in clinical development in JPsA range from monoclonal antibodies targeting interleukin (IL)-17, IL-12/23 and IL-23 blockades to synthetic small molecules targeting Janus kinase and tyrosine kinase and phosphodiesterase-4 inhibition. In addition, there are head-to-head clinical trials comparing tumour necrosis factor-α blockade with both IL-17 and IL-23 inhibition. Most of these new therapies have been tested in adults with psoriatic arthritis and have advanced to the phase III stage of drug development or received license for use, suggesting promising signals for efficacy and potentially acceptable safety and tolerability for JPsA. Further translational research in JPsA is required to improve our understanding of the impact of age at onset on treatment efficacy, as well as to provide opportunities for better management of refractory disease and improved long-term outcomes in JPsA, for ultimate patient benefit.

Belgian Patients of the European Registry for Hidradenitis Suppurativa (ERHS-Be): Data, Scores, and Phenotypes since 2015

INTRODUCTION

Hidradenitis suppurativa (HS) is a chronic inflammatory skin disease, characterized by painful and recurrent lesions in apocrine gland-bearing skin areas. It is a heterogeneous disease, which makes assessment and data collection difficult. Questionnaires with detailed items, such as the Belgian European Registry for Hidradenitis Suppurativa (ERHS-Be), are useful to study HS and its associated comorbidities. The aim of this registry was to uncover new factors associated with HS and understand HS patients' clinical profiles and efficacy of treatments.

MATERIAL AND METHODS

The ERHS-Be registry is based on questionnaires, with sections for sociodemographic data, medical and HS history, clinical examination, and treatment plan. It allows identification of different clinical phenotypes and automatic calculation of severity scores.

RESULTS

At present, 606 patients are included in the ERHS-Be (67% women, 33% men). The mean age at the first visit is 38.5 years. Tobacco use is present in 72.6% of patients. A family history of HS is noted in 42% of patients. Comorbidities are documented in this cohort: depression is present in 43.8% of patients, arthritis in 27.8%, obesity in 31.5%, hypertension in 10.6%, diabetes mellitus in 6.4%, and dyslipidemia in 12.4%. Moreover, 7.7% of patients suffer from IBD and 27.4% have a pilonidal sinus. History of severe acne is found in 32.1% of patients and psoriasis in 9.3%. Thirteen percent of women in our cohort suffer from polycystic ovarian syndrome. Severity of disease is quantified in 533 patients: for instance, Hurley I, II, and III scores proportions are, respectively, 32.3%, 52.7%, and 15%, while the mean IHS4 score is 5.2. This registry also enables determination of relative phenotype proportions in our cohort, according to different classifications.

CONCLUSION

The ERHS-Be questionnaires allow systematic and larger data collection, including detailed comorbidities, phenotypes, and severity of disease. Analysis of this large database will contribute to a better understanding and management of HS, at a time where new therapeutic options are becoming available.

Role of pH-sensing receptors in colitis

Low pH in the gut is associated with severe inflammation, fibrosis, and colorectal cancer (CRC) and is a hallmark of active inflammatory bowel disease (IBD). Subsequently, pH-sensing mechanisms are of interest for the understanding of IBD pathophysiology. Tissue hypoxia and acidosis-two contributing factors to disease pathophysiology-are linked to IBD, and understanding their interplay is highly relevant for the development of new therapeutic options. One member of the proton-sensing G protein-coupled receptor (GPCR) family, GPR65 (T-cell death-associated gene 8, TDAG8), was identified as a susceptibility gene for IBD in a large genome-wide association study. In response to acidic extracellular pH, GPR65 induces an anti-inflammatory response, whereas the two other proton-sensing receptors, GPR4 and GPR68 (ovarian cancer G protein-coupled receptor 1, OGR1), mediate pro-inflammatory responses. Here, we review the current knowledge on the role of these proton-sensing receptors in IBD and IBD-associated fibrosis and cancer, as well as colitis-associated cancer (CAC). We also describe emerging small molecule modulators of these receptors as therapeutic opportunities for the treatment of IBD.

Colitis induced by IL-17A-inhibitors

BACKGROUND

Interleukin (IL)-17A is essential for intestinal mucosal integrity, contributing to the prevention of detrimental immunity such as infectious colitis and inflammatory bowel disease (IBD). Indeed, neutralization of IL-17A has been abandoned as a therapeutic principle in IBD because of increased disease activity. However, it is controversial whether IL-17A inhibitors increase the risk of developing colitis in patients who do not have underlying IBD. Here, we present two cases of different forms of colitis that occurred during treatment with two IL-17A inhibitors, secukinumab and ixekizumab.

CASE PRESENTATIONS

We report the case of a 35-year-old female with SAPHO (synovitis-acne-pustulosis-hyperostosis-osteitis) syndrome who was admitted due to severe colitis with bloody diarrhea, fever, abdominal pain and weight loss after receiving secukinumab for 3 months as well as the case of a 41-year-old male with psoriatic arthritis who presented himself to the outpatient clinic with bloody stools, abdominal pain and nausea 5 months after changing his therapy from secukinumab to ixekizumab. In both patients, treatment with IL-17A-inhibitors was stopped and tumor necrosis factor inhibitors were started. Both patients recovered, are clinically stable and show no more signs of active colitis.

CONCLUSION

The role of IL-17A inhibitors in the pathogenesis of infectious colitis and new-onset IBD is not fully understood and requires further research. Patients receiving IL-17A-inhibitor therapy should be carefully screened and notified of the possible side effects.

Discerning Endoscopic Severity of Inflammatory Bowel Disease by Scoping the Peripheral Blood Transcriptome

Background and Aims

Ulcerative colitis (UC) and Crohn's disease (CD) are chronic inflammatory bowel diseases (IBDs) with an incompletely understood etiology and pathogenesis. Identification of suitable drug targets and assessment of disease severity are crucial for optimal management.

Methods

Using RNA sequencing, we investigated differential gene expression in peripheral blood samples from IBD patients and non-inflamed controls, analyzed pathway enrichment, and identified genes whose expression correlated with endoscopic disease severity.

Results

Neutrophil degranulation emerged as the most significant pathway across all IBD sample types. Signaling by interleukins was prominent in patients with active intestinal inflammation but also enriched in CD and UC patients without intestinal inflammation. Nevertheless, genes correlated to endoscopic disease severity implicated the primary cilium in CD patients and translation and focal adhesion in UC patients. Moreover, several of these genes were located in genome-wide associated loci linked to IBD, cholesterol levels, blood cell counts, and levels of markers assessing liver and kidney function. These genes also suggested connections to intestinal epithelial barrier dysfunction, contemporary IBD drug treatment, and new actionable drug targets. A large number of genes associated with endoscopic disease severity corresponded to noncoding RNAs.

Conclusion

This study revealed biological pathways associated with IBD disease state and endoscopic disease severity, thus providing insights into the underlying mechanisms of IBD pathogenesis as well as identifying potential biomarkers and therapies. Peripheral blood might constitute a suitable noninvasive diagnostic sample type, in which gene expression profiles might serve as indicators of ongoing mucosal inflammation, and thus guide personalized treatment decisions.

Serum biomarkers and their relationship to axial spondyloarthritis associated with inflammatory bowel diseases

Spondyloarthritis (SpA) constitute a group of chronic inflammatory immune-mediated rheumatic diseases characterized by genetic, clinical, and radiological features. Recent efforts have concentrated on identifying biomarkers linked to axial SpA associated with inflammatory bowel disease (IBD), offering predictive insights into disease onset, activity, and progression. Genetically, the significance of the HLA-B27 antigen is notably diminished in ankylosing spondylitis (AS) associated with IBD, but is heightened in concurrent sacroiliitis. Similarly, certain polymorphisms of endoplasmic reticulum aminopeptidase (ERAP-1) appear to be involved. Carriage of variant NOD2/CARD15 polymorphisms has been demonstrated to correlate with the risk of subclinical intestinal inflammation in AS. Biomarkers indicative of pro-inflammatory activity, including C-reactive protein (CRP) along with erythrocyte sedimentation rate (ESR), are among the consistent predictive biomarkers of disease progression. Nevertheless, these markers are not without limitations and exhibit relatively low sensitivity. Other promising markers encompass IL-6, serum calprotectin (s-CLP), serum amyloid (SAA), as well as biomarkers regulating bone formation such as metalloproteinase-3 (MMP-3) and Dickkopf-related protein 1 (DKK-1). Additional candidate indicators of structural changes in SpA patients include matrix metalloproteinase-3 (MMP-3), vascular endothelial growth factor (VEGF), tenascin C (TNC), and CD74 IgG. Fecal caprotein (f-CLP) levels over long-term follow-up of AS patients have demonstrated predictive value in anticipating the development of IBD. Serologic antibodies characteristic of IBD (ASCA, ANCA) have also been compared; however, results exhibit variability. In this review, we will focus on biomarkers associated with both axial SpA and idiopathic intestinal inflammation, notably enteropathic spondyloarthritis.

Is the use of secukinumab after anti-TNF therapy greater than expected for the risk of developing inflammatory bowel disease?

OBJECTIVE

In this study, our objective was to present real-life data on the incidence of inflammatory bowel disease (IBD) among patients receiving secukinumab treatment.

METHODS

The study consisted of 209 patients who had prior exposure to anti-tumor necrosis factor (TNF) or were biologically naive. Patients with a pre-existing history of IBD were excluded from the study.

RESULTS

Of the 209 patients in the study, 176 (84.3%) had ankylosing spondylitis, while 33 (15.7%) had psoriatic arthritis. 112 (53.6%) patients had prior exposure to at least one anti-TNF treatment before initiating secukinumab. IBD developed in 10 (4.8%) of the 209 patients. The incidence of IBD among patients who initiated secukinumab as their first biologic agent was 1%. For patients who had previously received any anti-TNF treatment and subsequently transitioned to secukinumab, the incidence of IBD was 8% (p=0.018, odds ratio (OR): 8.38, 95% CI: 1.04-67.45). A mean of 3.67 months (±4.3) after anti-TNF use, whereas IBD symptoms developed in the biologically naive patient after 15 months.

CONCLUSION

Our study observed IBD incidence in 4.8% of patients using secukinumab. Patients who initiated secukinumab after previous anti-TNF treatment exhibited a significantly higher rate and risk of developing IBD. The onset of IBD occurred earlier in these patients (mean 3.67 months), whereas a single case of IBD showed a longer duration (15 months). Further studies with larger patient numbers are warranted to provide a more comprehensive understanding of our findings.

Sequential administration of paricalcitol followed by IL-17 blockade for progressive refractory IgA nephropathy patients

There is no established treatment for progressive IgA nephropathy refractory to steroids and immunosuppressant drugs (r-IgAN). Interleukin 17 (IL-17) blockade has garnered interest in immune-mediated diseases involving the gut-kidney axis. However, single IL-17A inhibition induced paradoxical effects in patients with Crohn's disease and some cases of de novo glomerulonephritis, possibly due to the complete Th1 cell response, along with the concomitant downregulation of regulatory T cells (Tregs). Seven r-IgAN patients were treated with at least six months of oral paricalcitol, followed by the addition of subcutaneous anti-IL-17A (secukinumab). After a mean follow-up of 28 months, proteinuria decreased by 71% (95% CI: 56-87), P < 0.001. One patient started dialysis, while the annual eGFR decline in the remaining patients [mean (95% CI)] was reduced by 4.9 mL/min/1.73 m2 (95% CI: 0.1-9.7), P = 0.046. Circulating Th1, Th17, and Treg cells remained stable, but Th2 cells decreased, modifying the Th1/Th2 ratio. Intriguingly, accumulation of circulating Th17.1 cells was observed. This novel sequential therapy appears to optimize renal advantages in patients with r-IgAN and elicit alterations in potentially pathogenic T helper cells.

Ustekinumab as a Treatment for Ixekizumab-Associated New-Onset Crohn's Disease in a Patient with Psoriasis

Interleukin-17 inhibitors are effective treatments for plaque psoriasis. However, these medications have been linked to the development of new-onset inflammatory bowel disease (IBD) and the worsening of existing IBD in some patients. This case report describes a patient with plaque psoriasis who developed new-onset Crohn's disease after treatment with ixekizumab, an interleukin-17A inhibitor. He was then transitioned to ustekinumab, which resulted in successful remission of both psoriasis and Crohn's disease. This case highlights the potential for ustekinumab to be an effective rescue treatment for psoriasis patients with new-onset IBD triggered by medications.

Cosentyx alleviates psoriasis-induced podocyte injury by inhibiting the tlr/nf-κb signaling pathway

BACKGROUND

Pathological studies have shown an association between psoriasis and renal podocyte injury, and the specific mechanism of podocyte injury in psoriasis remains unclear, with no effective treatments currently available. This study aimed to investigate the underlying mechanisms of podocyte and epidermal cell injury in psoriasis and evaluate the therapeutic effect of Cosentyx.

MATERIALS AND METHODS

A psoriasis-like mouse model was established using BALB/C mice, and Cosentyx treatment was administered via intraperitoneal injection. Various parameters, including skin lesions, urinary protein, kidney/serum inflammatory cytokines, kidney function, podocyte membrane proteins, and Toll-like receptors/nuclear factor kappa-b (TLR/NF-κB) pathway-associated proteins, were analyzed to explore the mechanisms of podocyte and epidermal cell injury in psoriasis and the potential ameliorative effects of Cosentyx.

RESULT

Treatment with Cosentyx significantly reduced the increased levels of urinary protein, creatinine, and blood urea nitrogen caused by psoriasis. Cosentyx inhibited the upregulation of kidney/serum inflammatory factors (IL-17, IL-1β, IL-6, TNF-α, and IL-22) and TLR/NF-κB-related proteins (TLR2, TLR4, MyD88, and NF-κBp65) in both psoriatic skin and kidney tissues, while also reducing the accumulation of oxidative products. Moreover, Cosentyx treatment suppressed podocyte apoptosis and promoted epidermal cell apoptosis. The experimental data demonstrated that psoriasis-like inflammation impaired renal podocytes through the TLR/NF-κB signaling pathway.

CONCLUSION

Cosentyx treatment effectively inhibited the expression of TLR/NF-κB-related proteins, providing a therapeutic effect for psoriasis-induced kidney and skin injuries.

Human intestinal organoids: Modeling gastrointestinal physiology and immunopathology - current applications and limitations

Human intestinal organoids are an ideal model system for studying gastrointestinal physiology and immunopathology. Altered physiology and mucosal immune response are hallmarks of numerous intestinal functional and inflammatory diseases, including inflammatory bowel disease (IBD), coeliac disease, irritable bowel syndrome (IBS), and obesity. These conditions impact the normal epithelial functions of the intestine, such as absorption, barrier function, secretion, and host-microbiome communication. They are accompanied by characteristic intestinal symptoms and have significant societal, economic, and healthcare burdens. To develop new treatment options, cutting-edge research is required to investigate their etiology and pathology. Human intestinal organoids derived from patient tissue recapitulate the key physiological and immunopathological aspects of these conditions, providing a promising platform for elucidating disease mechanisms. This review will summarize recent reports on patient-derived human small intestinal and colonic organoids and highlight how these models have been used to study intestinal epithelial functions in the context of inflammation, altered physiology, and immune response. Furthermore, it will elaborate on the various organoid systems in use and the techniques/assays currently available to study epithelial functions. Finally, it will conclude by discussing the limitations and future perspectives of organoid technology.

Assessment of safety profile of secukinumab in real-world scenario using United States food and drug administration adverse event reporting system database

Secukinumab is an anti-IL-17 monoclonal antibody approved for treating psoriasis and various arthritides. A comprehensive evaluation of its safety, especially in a real-world setting, is necessary. This study aimed to describe the adverse events (AE) associated with secukinumab use using the United States Food and Drug Administration Adverse Event Reporting System (FAERS) database. FAERS data files containing AE reports from 2015 to 2021 were downloaded for data mining. Primary or secondary suspect medications indicated for psoriasis were identified and analyzed. Medical dictionary for regulatory activities (MedDRA version 24.1) was used to analyze the AE terms. To detect potential safety signals of AE from secukinumab use, disproportionality analysis was used. A total of 365,590 adverse event reports were identified; of these, 44,761 reports involved the use of secukinumab. Safety signals were identified for ocular infections and gastrointestinal adverse events at the standardised MedDRA query level. Safety signals for oral candidiasis, oral herpes, conjunctivitis, eye infections, and ulcerative colitis were identified at the preferred term level. The findings of our study are consistent with those of earlier studies, such as the increased risk of infections and inflammatory bowel disease. However, our study also identified additional safety signals that need to be further evaluated.

Effect of Oral Chondroitin Sulfate Supplementation on Acute Brain Injury in a Murine Necrotizing Enterocolitis Model

BACKGROUND

Necrotizing enterocolitis (NEC) is a devastating condition where inflammatory changes and necrosis in the gut results in activation of brain microglia and subsequent neurodevelopmental impairment. Chondroitin sulfate (CS) is a glycosaminoglycan in human breast milk that is absent in conventional formulas. We hypothesized that oral formula supplementation with CS during a murine model of experimental NEC would not only attenuate intestinal injury, but also brain injury.

STUDY DESIGN

NEC was induced in mouse pups on postnatal days (PNDs) 5 to 8. Three conditions were studied: (1) breastfed controls, (2) NEC, and (3) NEC+enteral CS (formula+200 mg/kg/d of CS). Pups were euthanized on PND 9 or reunited with dams by the evening of PND 8. Intestinal segments were H&E stained, and immunohistochemistry was performed on brain tissue for Iba-1 to assess for microglial morphology and cortical changes. Neurodevelopmental assays were performed on mice reunited with foster dams on PND 9. Single-cell RNA-sequencing analysis was performed on human intestinal epithelial cells exposed to (1) nothing, (2) hydrogen peroxide (H 2 O 2 ) alone, or (3) H 2 O 2 + CS to look at the differential gene expression between groups. Groups were compared with ANOVA or Kruskal-Wallis tests as appropriate with p < 0.05 considered significant.

RESULTS

Compared with NEC, mice treated with oral CS showed improved clinical outcomes, decreased intestinal injury, and attenuated microglial activation and deleterious cortical change. Mice with CS performed better on early neurodevelopmental assays when compared with NEC alone. Single-cell analysis of HIEC-6 cells demonstrated that CS treatment down regulated several inflammatory pathways including nuclear factor κB-suggesting an explanation for the improved Th17 intestinal cytokine profile.

CONCLUSIONS

Oral CS supplementation improved both physiological, clinical, and developmental outcomes. These data suggest that CS is a safe compound for formula supplementation for the prevention of NEC.

Intestinal microbiota-specific Th17 cells possess regulatory properties and suppress effector T cells via c-MAF and IL-10

Commensal microbes induce cytokine-producing effector tissue-resident CD4+ T cells, but the function of these T cells in mucosal homeostasis is not well understood. Here, we report that commensal-specific intestinal Th17 cells possess an anti-inflammatory phenotype marked by expression of interleukin (IL)-10 and co-inhibitory receptors. The anti-inflammatory phenotype of gut-resident commensal-specific Th17 cells was driven by the transcription factor c-MAF. IL-10-producing commensal-specific Th17 cells were heterogeneous and derived from a TCF1+ gut-resident progenitor Th17 cell population. Th17 cells acquired IL-10 expression and anti-inflammatory phenotype in the small-intestinal lamina propria. IL-10 production by CD4+ T cells and IL-10 signaling in intestinal macrophages drove IL-10 expression by commensal-specific Th17 cells. Intestinal commensal-specific Th17 cells possessed immunoregulatory functions and curbed effector T cell activity in vitro and in vivo in an IL-10-dependent and c-MAF-dependent manner. Our results suggest that tissue-resident commensal-specific Th17 cells perform regulatory functions in mucosal homeostasis.

Dual function of fungi-derived cytokines in inflammatory bowel diseases: protection or inflammation

Inflammatory bowel disease (IBD) is an immune-mediated inflammatory condition involving both the innate and adaptive immune systems. Recently, the role of intestinal fungal flora and their downstream immune pathways has been highlighted in the pathogenesis of IBD. Cytokines as primary immune mediators require a delicate balance for maintaining intestinal homeostasis. Although most cytokines have a predictable role in either amplifying or attenuating inflammation in IBD, a few cytokines have shown a dual function in the inflammatory state of the intestine. Some of these dual-faced cytokines are also involved in mucosal anti-microbial defense pathways, particularly against intestinal fungal residents. Here, we reviewed the role of these cytokines in IBD pathogenesis to achieve a better understanding of the fungal interactions in the development of IBD.

Alpha-tocopherylquinone-mediated activation of the Aryl Hydrocarbon Receptor regulates the production of inflammation-inducing cytokines and ameliorates intestinal inflammation

This study investigated the role of Alpha-tocopherylquinone (TQ) in regulating the intestinal immune system and the underlying mechanisms. In the experimental dextran sodium sulfate and T cell-mediated colitis models, TQ significantly reduced the mRNA levels of interleukin (IL)-6, IL-1β, IL-17A, IL-23, and tumor necrosis factor (TNF)-α and the abundance of proinflammatory macrophages, T helper (Th)17 cells, and ILC3s in the colons of wild-type mice. TQ also prevented lipopolysaccharide (LPS)-induced activation of NFκB and signal transducer and activator of transcription (Stat)-3 pathways in the human macrophage U937 cells. Pharmacological inhibition or CRISPR-Cas-9-mediated knockout of Aryl hydrocarbon Receptor (AhR) prevented the anti-inflammatory effects of TQ in the LPS-treated U937 cells. Furthermore, TQ reduced the mRNA levels of the LPS-induced pro-inflammatory cytokines in the WT but not Ahr-/- mice splenocytes. TQ also reduced IL-6R protein levels and IL-6-induced Stat-3 activation in Jurkat cells and in vitro differentiation of Th17 cells from wild-type but not Ahr-/- mice naive T cells. Additionally, TQ prevented the pro-inflammatory effects of LPS on macrophages and stimulation of T cells in human PBMCs and significantly reduced the abundance of tumor necrosis factor-α, IL-1β, and IL-6hi inflammatory macrophages and Th17 cells in surgically resected Crohn's disease (CD) tissue. Our study shows that TQ is a naturally occurring, non-toxic, and effective immune modulator that activates AhR and suppresses the Stat-3-NFκB signaling.

Current Pharmacological Therapies for the Management of Spondyloarthritis: Special Considerations in Older Patients

Spondylarthritis (SpA) is generally observed in young male patients but can be diagnosed in older patients. These cases correspond to late-onset SpA (LoSpA) with two main clinical presentations, axial and peripheral SpA. Another increasingly common situation is that of older patients who have had SpA for many years. The therapeutic management of LoSpA is quite smilar to the management of patients with an early-onset disease, combining both non-pharmacological and pharmacological treatments. The treatments that can be used in LoSpA include non-steroidal anti-inflammatory drugs (NSAIDs) and biological agents targeting TNFα or IL-17A. Janus kinase inhibitors (JAKi) were recently introduced on the market for SpA. TNF inhibitors and IL-17inhibitors are very effective drugs in early-onset SpA. The effectiveness and safety of targeted therapies have not been specifically evaluated in LoSpA or older patients, and thus caution is required for these patients with comorbidities and/or polymedication. According to indirect data, biological agents seem to be less effective in LoSpA compared with early-onset disease. In parallel, a careful evaluation for the risk of infection, malignancy and cardiovascular events is recommended before initiating these drugs in this age category. JAKi may be used in LoSpA, but only in selected patients according to recent recommendations from the US Food and Drug Administration (FDA) and the European Medicines Agency (EMA). When considering that the prevalence of such situations is expected to increase as ageing progresses, it is certainly time to consider this patient category as a distinct subgroup within the spectrum of SpA. Specific studies evaluating targeted agents in this age category are thus desirable.

Identification CCL2,CXCR2,S100A9 of the immune-related gene markers and immune infiltration characteristics of inflammatory bowel disease and heart failure via bioinformatics analysis and machine learning

Background

Recently, heart failure (HF) and inflammatory bowel disease (IBD) have been considered to be related diseases with increasing incidence rates; both diseases are related to immunity. This study aims to analyze and identify immune-related gene (IRG) markers of HF and IBD through bioinformatics and machine learning (ML) methods and to explore their immune infiltration characteristics.

Methods

This study used gene expressiondata (GSE120895, GSE21610, GSE4183) from the Gene Expression Omnibus (GEO) database to screen differentially expressed genes (DEGs) and compare them with IRGs from the ImmPort database to obtain differentially expressed immune-related genes (DIRGs). Functional enrichment analysis of IRGs was performed using Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG). Subsequently, three machine models and protein-protein interactions (PPIs) were established to identify diagnostic biomarkers. The receiver operating characteristic (ROC) curves were applied to evaluate the diagnostic value of the candidate biomarkersin the validation set (GSE1145, GSE36807) and obtain their correlations with immune cells through the Spearman algorithm. Finally, the CIBERSORT algorithm was used to evaluate the immune cell infiltration of the two diseases.

Results

Thirty-four DIRGs were screened and GO and KEGG analysis results showed that these genes are mainly related to inflammatory and immune responses. CCL2, CXCR2 and S100A9 were identified as biomarkers.The immune correlation results indicated in both diseases that CCL2 is positively correlated with mast cell activation, CXCR2 is positively correlated with neutrophils and S100A9 is positively correlated with neutrophils and mast cell activation. Analysis of immune characteristics showed that macrophages M2, macrophages M0 and neutrophils were present in both diseases.

Conclusions

CCL2, CXCR2 and S100A9 are promising biomarkers that will become potential immunogenetic biomarkers for diagnosing comorbidities of HF and IBD. macrophages M2, macrophages M0, neutrophil-mediated inflammation and immune regulation play important roles in the development of HF and IBD and may become diagnostic and therapeutic targets.

Management Strategies for Pediatric Moderate-to-Severe Plaque Psoriasis: Spotlight on Biologics

Although psoriasis onset has been reported at any ages, in up to one-third of cases, it begins during childhood, with an estimated prevalence of about 2% in pediatric population. The management of moderate-to-severe forms of childhood psoriasis may represent a challenge for dermatologists, especially for parents' concerns about the need of systemic treatments. However, a prompt safe and effective treatment is mandatory in these patients, due to the significative impact that psoriasis may have on their quality of life, with well-known consequences on psychological health of both patients and caregivers. Due to the relatively frequent parents' refusal of systemic treatments, probably due to the fear of eventual adverse events, difficulties of oral or injective route, the management of moderate-to-severe forms still represents a challenge. Herein, we report a narrative review, aiming to resume the systemic treatments for pediatric psoriasis, focusing on the use of biologics and small molecules in the pediatric ages. The most widely used therapeutic strategies today for the pediatric population with moderate-severe psoriasis are traditional systemic therapies, while more innovative drugs such as biologics and small molecules now represent a somewhat unexplored but certainly promising field for unresponsive patients.

Inflammation and Psoriasis: A Comprehensive Review

Psoriasis is an immune-mediated disease with a strong genetic component that brings many challenges to sick individuals, such as chronic illness, and which has multiple associated comorbidities like cardiovascular disease, metabolic syndrome, inflammatory bowel disease, and psychological disorders. Understanding the interplay between the innate and adaptative immune system has led to the discovery of specific cytokine circuits (Tumor Necrosis Factor-alpha (TNF-α), IL-23, IL-17), which has allowed scientists to discover new biomarkers that can be used as predictors of treatment response and pave the way for personalized treatments. In this review, we describe the footprint psoriasis leaves on the skin and beyond, key pathophysiological mechanisms, current available therapeutic options, and drawbacks faced by existing therapies, and we anticipate potential future perspectives that may improve the quality of life of affected individuals.

Mucosal-associated invariant T cells from Clostridioides difficile-infected patients exhibit a distinct proinflammatory phenotype and enhanced cytotoxic activity

Mucosal-associated invariant T (MAIT) cells are innate-like T cells mainly found in the mucosa and peripheral blood. We have recently demonstrated that Clostridioides difficile activates MAIT cells in vitro. However, their role in the pathogenesis of C. difficile infection (CDI) in human patients remains elusive to date. In this study, we performed comprehensive immunophenotyping of MAIT cells derived from CDI patients and compared their phenotype to that of patients with inflammatory bowel diseases (IBD) and healthy controls. Our study revealed that blood MAIT cells from CDI patients exhibit an interleukin 17a (IL-17a)-dominated proinflammatory phenotype and an increased readiness to synthesize the proinflammatory cytokine interferon γ (IFN-γ) following in vitro re-stimulation. Moreover, the cytotoxic activity of MAIT cells, as measured by surface CD107a and intracellular granzyme B expression, was strongly increased in CDI. Multi epitope ligand cartography (MELC) analysis of intestinal biopsies from CDI patients revealed that MAIT cells exhibit an increased production of granzyme B and increased cytotoxicity compared to the control group. Together with previously published in vitro data from our group, our findings suggest that MAIT cells are functionally involved in the immune response against C. difficile and contribute to the pathogenesis of CDI.

New biologic (Ab-IPL-IL-17) for IL-17-mediated diseases: identification of the bioactive sequence (nIL-17) for IL-17A/F function

OBJECTIVES

Interleukin (IL) 17s cytokines are key drivers of inflammation that are functionally dysregulated in several human immune-mediated inflammatory diseases (IMIDs), such as rheumatoid arthritis (RA), psoriasis and inflammatory bowel disease (IBD). Targeting these cytokines has some therapeutic benefits, but issues associated with low therapeutic efficacy and immunogenicity for subgroups of patients or IMIDs reduce their clinical use. Therefore, there is an urgent need to improve the coverage and efficacy of antibodies targeting IL-17A and/or IL-17F and IL-17A/F heterodimer.

METHODS AND RESULTS

Here, we initially identified a bioactive 20 amino acid IL-17A/F-derived peptide (nIL-17) that mimics the pro-inflammatory actions of the full-length proteins. Subsequently, we generated a novel anti-IL-17 neutralising monoclonal antibody (Ab-IPL-IL-17) capable of effectively reversing the pro-inflammatory, pro-migratory actions of both nIL-17 and IL-17A/F. Importantly, we demonstrated that Ab-IPL-IL-17 has less off-target effects than the current gold-standard biologic, secukinumab. Finally, we compared the therapeutic efficacy of Ab-IPL-IL-17 with reference anti-IL-17 antibodies in preclinical murine models and samples from patients with RA and IBD. We found that Ab-IPL-IL-17 could effectively reduce clinical signs of arthritis and neutralise elevated IL-17 levels in IBD patient serum.

CONCLUSIONS

Collectively, our preclinical and in vitro clinical evidence indicates high efficacy and therapeutic potency of Ab-IPL-IL-17, supporting the rationale for large-scale clinical evaluation of Ab-IPL-IL-17 in patients with IMIDs.

Targeted Treatment of Diseases of Immune Dysregulation

Increasing molecular knowledge of autoinflammatory and autoimmune disorders has enabled more targeted treatment of these conditions. Treatment of inflammasomopathies is often aimed at interleukin-1 (IL-1) blockade, with potential use of other inhibitors targeting cytokines such as IL-18 and IL-6. Interferonopathies and some disorders with overlap features of autoimmunity and autoinflammation may improve with Janus kinase inhibition. Autoimmune conditions may also respond to inhibition of different cytokines, as well as to inhibition of T and B lymphocytes. Effective treatment is increasingly possible through targeted/precision medicine approaches.

Immune-mediated inflammatory diseases: Common and different pathogenic and clinical features

The term "immune-mediated inflammatory diseases (IMIDs)" refers to several inflammatory pathologies of multifactorial etiology and involving either simultaneously or sequentially more organs. IMIDs share some common pathogenic mechanisms, which account for some similarities in the clinical course and the impact that these diseases may have on other organs and systems of the body. However, there are some differences in the IMID-associated pathological process, including the synthesis and function of multiple inflammatory cytokines, which are supposed to perpetuate the tissue-damaging inflammation. This justifies the different indications and responsiveness to corticosteroids, immunosuppressors, small molecules, and biologics. Many individuals with IMIDs are, however, intolerant, or unresponsive to the current drugs, thus suggesting the necessity of novel therapeutic approaches, such as the combination of compounds that either inhibit more immuno-inflammatory networks selectively or simultaneously suppress inflammatory signals and activate counter-regulatory pathways. In this article, we highlight the most relevant features of IMIDs and discuss how clinicians can combat the detrimental immune response in such disorders.

Hidradenitis suppurativa presents a methylome dysregulation capable to explain the pro-inflammatory microenvironment: Are these DNA methylations potential therapeutic targets?

BACKGROUND

Hidradenitis suppurativa (HS) is a chronic, systemic, inflammatory skin condition with elusive pathogenesis that affects therapeutic intervention directly.

OBJECTIVE

To characterize epigenetic variations in cytokines genes contributing to HS.

METHODS

Epigenome-wide DNA methylation profiling with the Illumina Epic array was performed on blood DNA samples from 24 HS patients and 24 age- and sex-matched controls to explore DNA methylation changes in cytokine genes.

RESULTS

We identified 170 cytokine genes including 27 hypermethylated CpG sites and 143 genes with hypomethylated sites respectively. Hypermethylated genes, including LIF, HLA-DRB1, HLA-G, MTOR, FADD, TGFB3, MALAT1 and CCL28; hypomethylated genes, including NCSTN, SMAD3, IGF1R, IL1F9, NOD2, NOD1, YY1, DLL1 and BCL2 may contribute to the pathogenesis of HS. These genes were enriched in the 117 different pathways (FDR p-values ≤ 0.05), including IL-4/IL-13 pathways and Wnt/β-catenin signalling.

CONCLUSIONS

The lack of wound healing, microbiome dysbiosis and increased tumour susceptibility are all sustained by these dysfunctional methylomes, hopefully, capable to be targeted in the next future. Since methylome describes and summarizes genetic and environmental contributions, these data may represent a further step towards a feasible precision medicine also for HS patients.

Chondroitin sulfate supplementation improves clinical outcomes in a murine model of necrotizing enterocolitis

Necrotizing enterocolitis (NEC) continues to be a devastating disease in preterm neonates and has a paucity of medical management options. Chondroitin sulfate (CS) is a naturally occurring glycosaminoglycan (GAG) in human breast milk (HM) and has been shown to reduce inflammation. We hypothesized that supplementation with CS in an experimental NEC model would alter microbial diversity, favorably alter the cytokine profile, and (like other sulfur compounds) improve outcomes in experimental NEC via the eNOS pathway. NEC was induced in 5-day-old pups. Six groups were studied (n = 9-15/group): (1) WT breastfed and (2) Formula fed controls, (3) WT NEC, (4) WT NEC + CS, (5) eNOS KO (knockout) NEC, and (6) eNOS KO NEC + CS. Pups were monitored for clinical sickness score and weights. On postnatal day 9, the pups were killed. Stool was collected from rectum and microbiome analysis was done with 16 s rRNA sequencing. Intestinal segments were examined histologically using a well-established injury scoring system and segments were homogenized and analyzed for cytokine profile. Data were analyzed using GraphPad Prism with p < 0.05 considered significant. CS supplementation in formula improved experimental NEC outcomes when compared to NEC alone. CS supplementation resulted in similar improvement in NEC in both the WT and eNOS KO mice. CS supplementation did not result in microbial changes when compared to NEC alone. Our data suggest that although CS supplementation improved outcomes in NEC, this protection is not conferred via the eNOS pathway or alteration of microbial diversity. CS therapy in NEC does improve the intestinal cytokine profile and further experiments will explore the mechanistic role of CS in altering immune pathways in this disease.

Secukinumab-induced IgA vasculitis in a patient with psoriatic arthritis

OBJECTIVES

Secukinumab (SEC) is an effective and widely used drug in psoriatic disease and axial spondyloarthritis. However, SEC has been found to be associated with inflammatory conditions and vasculitis. These inflammatory adverse effects may complicate the treatment of underlying disease, and clinicians may experience difficulties in recognizing and managing this unusual condition.

CASE REPORT

A man aged 56 years with psoriatic disease refractory to conventional disease-modifying antirheumatic drugs was given adalimumab for 6 weeks, then switched to SEC when his psoriatic lesions were exacerbated. After 3 weeks of SEC treatment, he developed systemic features of IgA vasculitis while his skin lesions and arthritis persisted.

CONCLUSIONS

Although SEC-related inflammatory adverse events, including vasculitis, are rarely encountered in clinical practice, it is essential to recognize them because they can be mistaken as a component of the underlying inflammatory disease. In addition, the dramatic improvement in many cases after the cessation of SEC underlines the importance of making an accurate diagnosis. Pathogenetically, these adverse events are likely to be paradoxical reactions, except for SEC-induced inflammatory bowel diseases. However, in many aspects, their pathogenesis is controversial and needs clarification.

Advances in pharmacotherapies for axial spondyloarthritis

INTRODUCTION

Axial spondyloarthritis (axSpA) refers to an inflammatory rheumatic disease that mainly affects the axial skeleton and leads to progressive radiographic changes of the sacroiliac joints and spine. axSpA is currently subdivided into the radiographic (r-axSpA) and non-radiographic (nr-axSpA) form. Both forms are associated with musculoskeletal pain, restriction of spinal mobility, specific extra-musculoskeletal manifestations, and overall, altered quality of life. The therapeutic management of axSpA is currently well standardized.

AREAS COVERED

We reviewed available literature (by using PubMed search) on non-pharmacological and pharmacological treatment options that may be used in axSpA, including r-axSpA and nr-axSpA, as well as the role of non-steroidal anti-inflammatory drugs (NSAIDs), biological agents including TNFalpha (TNFi) and IL-17 (IL-17i) inhibitors. New treatment options such as Janus kinase inhibitors are also reviewed.

EXPERT OPINION

NSAIDs remain the mainstay of initial therapy, and subsequently, biological agents (TNFi and IL-17i) may be envisaged. Four TNFi are licensed for the treatment of both r-axSpA and nr-axSpA, while IL-17i are approved in each indication. The choice between a TNFi and an IL-17i is mainly guided by the presence of extra-articular manifestations. JAKi were more recently introduced for the treatment of r-axSpA, but their use is restricted to specific patients with a safe cardiovascular profile.

Spondyloarthritides

The spondyloarthritides are a diverse group of distinct yet interrelated disease processes with overlapping clinical features. They are ankylosing spondylitis, reactive arthritis, inflammatory bowel disease-associated arthritis, and psoriatic arthritis. Genetically, these disease processes have been linked by the presence of HLA-B27. They manifest with axial and peripheral symptoms, such as inflammatory back pain, enthesitis, oligoarthritis, and dactylitis. The onset of symptoms can begin before the age of 45; however, because of the wide range of signs and symptoms, diagnosis can be delayed, leading to unchecked inflammation, structural damage, and later, restriction in physical mobility.

Secukinumab-Induced Crohn's Disease in a Patient Treated for Juvenile Idiopathic Arthritis

Juvenile idiopathic arthritis (JIA) is a common form of arthritis that occurs in children, typically with an onset before the age of 16 years. It can affect joints in any part of the body. As per the International League of Rheumatology, JIA is classified into systemic arthritis, oligoarthritis, extended oligoarthritis, polyarthritis (rheumatoid factor positive), polyarthritis (rheumatoid factor negative), enthesitis-related arthritis (ERA), juvenile psoriatic arthritis (JPsA), and other arthritis. JIA is treated with disease-modifying antirheumatic medications (DMARDs), which include both nonbiologic agents like methotrexate (MTX) and biologic agents like inhibitors of tumor necrosis factor-alpha, interleukin-1 (IL-1), IL-6, and T-cell co-stimulation modulators. As per recent studies, in December 2021, Secukinumab, an IL-17A inhibitor, is one of the most recent biologic agents approved for active ERA and JPsA. A few reports have suggested Secukinumab is related to new-onset inflammatory bowel diseases (IBDs). We present a case of a 20-year-old female who was being treated with Secukinumab for JIA, and six months into therapy, she developed symptoms suggestive of Crohn's disease (CD). The diagnosis was confirmed with colonoscopy, histopathology, and radiology results. Her symptoms completely resolved four weeks after discontinuing Secukinumab and oral steroid therapy. The efficacy and side effects of Secukinumab have been studied mainly on middle-aged populations who were being treated for psoriasis and ankylosing spondylitis (AS); however, there is limited literature on younger populations. With this case report, we would like to highlight the possible relationship between the development of IBD and Secukinumab therapy in the adolescent population and emphasize the importance of regular screening for IBD in this population.

Safety of guselkumab treatment for up to 5 years in patients with moderate-to-severe psoriasis: pooled analyses across seven clinical trials with more than 8600 patient-years of exposure

BACKGROUND

Guselkumab has demonstrated favourable safety and efficacy across individual clinical studies in adults with moderate-to-severe plaque psoriasis.

OBJECTIVES

To evaluate the safety of guselkumab in patients with psoriasis using pooled data from seven phase II/III studies (X-PLORE, VOYAGE 1, VOYAGE 2, NAVIGATE, ORION, ECLIPSE, Japan registration).

METHODS

All studies, except NAVIGATE and ECLIPSE (active comparator-controlled only), included a 16-week placebo-controlled period; X-PLORE, VOYAGE 1 and VOYAGE 2 included both placebo and active controls. In most studies, guselkumab-treated patients received 100-mg subcutaneous injections at week 0, week 4, and then every 8 weeks thereafter. Safety data were summarized for the placebo-controlled period (weeks 0-16) and through the end of the reporting period (up to 5 years). Incidence rates of key safety events were integrated post hoc, adjusted for the duration of follow-up and reported per 100 patient-years (PY).

RESULTS

During the placebo-controlled period, 544 patients received placebo (165 PY) and 1220 received guselkumab (378 PY). Through the end of the reporting period, 2891 guselkumab-treated patients contributed 8662 PY of follow-up. During the placebo-controlled period, in the guselkumab and placebo groups, respectively, rates of adverse events (AEs) were 346/100 PY and 341/100 PY, and infections were 95.9/100 PY and 83.6/100 PY. Rates of serious AEs (6.3/100 PY vs. 6.7/100 PY), AEs leading to discontinuation (5.0/100 PY vs. 9.7/100 PY), serious infections (1.1/100 PY vs. 1.2/100 PY), malignancy (0.5 patients/100 PY vs. 0.0 patients/100 PY) and major adverse cardiovascular events (MACE; 0.3/100 PY vs. 0.0/100 PY) were low and comparable between guselkumab and placebo. Through the end of the reporting period, safety event rates were lower than or comparable to the placebo-controlled period in guselkumab-treated patients: AEs, 169/100 PY; infections, 65.9/100 PY; serious AEs, 5.3/100 PY; AEs leading to discontinuation, 1.6/100 PY; serious infections, 0.9/100 PY; malignancy, 0.7/100 PY; and MACE, 0.3/100 PY. There were no cases of Crohn disease, ulcerative colitis, opportunistic infection or active tuberculosis related to guselkumab.

CONCLUSIONS

In this comprehensive analysis of 2891 guselkumab-treated patients with psoriasis followed for up to 5 years (8662 PY), guselkumab demonstrated favourable safety, consistent with previous reports. Safety event rates in guselkumab-treated patients were similar to those observed with placebo and were consistent throughout long-term treatment.

A diet rich in fermentable fiber promotes robust changes in the intestinal microbiota, mitigates intestinal permeability, and attenuates autoimmune uveitis

Therapeutic approaches for noninfectious uveitis have expanded greatly over the past 10 years, but are limited by potential side effects and limited efficacy. Thus, therapeutic approaches that include less toxic, potentially preventative strategies to manage noninfectious uveitis are essential areas of study. Diets rich in fermentable fiber are potentially preventative in various conditions such as metabolic syndrome and type 1 diabetes. We studied the effects of various fermentable dietary fibers in an inducible model of experimental autoimmune uveitis (EAU) and found that they differentially modulated uveitis severity. A high pectin diet was the most protective, reducing clinical disease severity through the induction of regulatory T lymphocytes and the suppression of Th1 and Th17 lymphocytes at peak ocular inflammation in either intestinal or extra-intestinal lymphoid tissues. The high pectin diet also promoted intestinal homeostasis as shown by changes in intestinal morphology and gene expression, as well as intestinal permeability. Pectin-induced modulation of intestinal bacteria appeared to be associated with protective changes in immunophenotype in the intestinal tract, and correlated with reduced uveitis severity. In summary, our current findings support the potential for dietary intervention as a strategy to mitigate noninfectious uveitis severity.

A Case of Paradoxical Reactions to Biologic Therapy for Psoriasis

Introduction

Psoriasis is an immune-mediated chronic inflammatory skin disease. As our understanding of the pathogenesis of psoriasis has improved, biologic agents have become increasingly important in the treatment of psoriasis. However, the use of biologic agents is associated with cutaneous side effects. A new type of side effect called paradoxical reactions is an emerging threat arising from the increasing use of biologic agents.

Case

Here, we present a case of paradoxical skin reactions - pyoderma gangrenosum (PG) and eczema - induced by biologic therapy. The case was successfully and eventually treated with baricitinib.

Discussion

PG is a rare inflammatory disease characterised by painful and necrotic ulcerations containing neutrophils. It has been associated with autoimmune diseases such as inflammatory bowel disease (IBD). TNF (tumor necrosis factor) -α inhibitors can effectively treat refractory PG, while IL (interleukin) -17A inhibitors may worsen IBD symptoms. The cause of PG in this case was believed to be secukinumab, not adalimumab. The patient was diagnosed with eczematous dermatitis due to TNF-α inhibitors, and baricitinib was added to treat eczematous dermatitis.

Conclusion

Paradoxical reactions are unpredictable events that may occur during treatment with biologics at anytime. They need further research in order to formulate personalised treatment.

Increased gut permeability and intestinal inflammation precede arthritis onset in the adjuvant-induced model of arthritis

BACKGROUND

Intestinal inflammation, dysbiosis, intestinal permeability (IP), and bacterial translocation (BT) have been identified in patients with spondyloarthritis but the time at which they appear and their contribution to the pathogenesis of the disease is still a matter of debate.

OBJECTIVES

To study the time-course of intestinal inflammation (I-Inf), IP, microbiota modification BT in a rat model of reactive arthritis, the adjuvant-induced arthritis model (AIA).

METHODS

Analysis was performed at 3 phases of arthritis in control and AIA rats: preclinical phase (day 4), onset phase (day 11), and acute phase (day 28). IP was assessed by measuring levels of zonulin and ileal mRNA expression of zonulin. I-inf was assessed by lymphocyte count from rat ileum and by measuring ileal mRNA expression of proinflammatory cytokines. The integrity of the intestinal barrier was evaluated by levels of iFABP. BT and gut microbiota were assessed by LPS, soluble CD14 levels, and 16S RNA sequencing in mesenteric lymph node and by 16S rRNA sequencing in stool, respectively.

RESULTS

Plasma zonulin levels increased at the preclinical and onset phase in the AIA group. Plasma levels of iFABP were increased in AIA rats at all stages of the arthritis course. The preclinical phase was characterized by a transient dysbiosis and increased mRNA ileal expression of IL-8, IL-33, and IL-17. At the onset phase, TNF-α, IL-23p19, and IL-8 mRNA expression were increased. No changes in cytokines mRNA expression were observed at the acute phase. Increased CD4⁺ and CD8⁺ T cell number was measured in the AIA ileum at day 4 and day 11. No increase in BT was observed.

CONCLUSION

These data show that intestinal changes precede the development of arthritis but argue against a strict "correlative" model in which arthritis and gut changes are inseparable.

Deciphering the pharmacological mechanisms of Fraxini Cortex for ulcerative colitis treatment based on network pharmacology and in vivo studies

BACKGROUND

Ulcerative colitis (UC) is a common type of inflammatory bowel disease. Due to the elusive pathogenesis, safe and effective treatment strategies are still lacking. Fraxini Cortex (FC) has been widely used as a medicinal herb to treat some diseases. However, the pharmacological mechanisms of FC for UC treatment are still unclear.

METHODS

An integrated platform combining network pharmacology and experimental studies was introduced to decipher the mechanism of FC against UC. The active compounds, therapeutic targets, and the molecular mechanism of action were acquired by network pharmacology, and the interaction between the compounds and target proteins were verified by molecular docking. Dextran sulfate sodium (DSS)-induced colitis model was employed to assess the therapeutic effect of FC on UC, and validate the molecular mechanisms of action predicted by network pharmacology.

RESULTS

A total of 20 bioactive compounds were retrieved, and 115 targets were predicted by using the online databases. Ursolic acid, fraxetin, beta-sitosterol, and esculetin were identified as the main active compounds of FC against UC. PPI network analysis identified 28 FC-UC hub genes that were mainly enriched in the IL-17 signaling pathway, the TNF signaling pathway, and pathways in cancer. Molecular docking confirmed that the active compounds had high binding affinities to the predicted target proteins. GEO dataset analysis showed that these target genes were highly expressed in the UC clinical samples compared with that in the healthy controls. Experimental studies showed that FC alleviated DSS-induced colitis symptoms, reduced inflammatory cytokines release, and suppressed the expression levels of IL1β, COX2, MMP3, IL-17 and RORγt in colon tissues.

CONCLUSION

FC exhibits anti-UC properties through regulating multi-targets and multi-pathways with multi-components. In vivo results demonstrated that FC alleviated DSS-induced colitis.

Discovery of Novel Sesquiterpene Lactone Derivatives as Potent PKM2 Activators for the Treatment of Ulcerative Colitis

The pyruvate kinase M2 (PKM2) can significantly affect the differentiation of Th17 and Treg cells; thus, it is considered a promising target for UC therapy. Herein, five series of costunolide (Cos) derivatives are designed, synthesized, and biologically evaluated. Among them, D5 exhibits excellent immunomodulatory activity against T-cell proliferation and potent PKM2 activating activity. Meanwhile, it has been confirmed that D5 can also covalently interact with Cys424 of PKM2. The molecular docking and molecular dynamic (MD) studies indicate that difluorocyclopropyl derivative of D5 improves the protein-ligand interaction by interacting with Arg399 electrostatically. Furthermore, D5 significantly dampens the differentiation of Th17 but not Treg cells to recover the Th17/Treg balance, which is attributed to the suppression of PKM2-mediated glycolysis. Oral administration of D5 ameliorates the symptoms of dextran sulfate sodium (DSS)- and 2,4,6-trinitro-benzenesulfonic acid (TNBS)-induced colitis in mouse model. Collectively, D5 has the potential to be developed as a novel anti-UC candidate.