HLA-Cw1 and Psoriasis

Allelic and haplotypic HLA analysis in patients with psoriatic arthritis: Low frequency of common alleles

Introduction

Psoriatic arthritis is a complex disease, and human leukocyte antigens (HLA) are key to its development. Latin America and, specifically, Colombia, has scarce data about patients with psoriatic arthritis.

Objective

To describe the genotypic, allelic and haplotypic frequency of HLA alleles in psoriatic arthritis and associate them with clinical variables.

Materials and methods

We conducted a retrospective study involving adult patients with psoriatic arthritis, evaluated according to CASPAR criteria, between 2012 and 2023. We included healthy donors whose HLA-A, B, C, and DR were genotyped by PCR/SSO in a Luminex 100/200 xMAP™ device. We performed an HLA comparative analysis between healthy donors and psoriatic arthritis patients.

Results

We included 401 healthy controls and 37 patients with psoriatic arthritis, in which we identified 46 genotypes, 75 alleles, and 32 haplotypes. The most frequent HLA were HLA-A*24 (37.1%), HLA-B*35 (20.8%), HLA-C*3 and HLA-C*7 (19.9% each), and HLADR* 4 (30%). Compared to healthy donors, the patient’s genotypic frequency was lower for HLA-A*02, HLA-A*11, HLA-B*35, HLA-DR*01, HLA-DR*07, HLA-DR*13, and HLA-DR*15 (p < 0.05), which means that even though HLA-B*35 was frequent in psoriatic arthritis, it's frequency was lower when compared to that of healthy controls. The frequency of HLA-A*24 and HLA-B*44 was different in cutaneous involvement (p < 0.05), HLA-B*40 and HLA-B*35 in joint involvement (p < 0.05), and HLA-A*26 and HLA-C*16 in extra-articular manifestations (p < 0.05). The allelic frequency of HLA-A*26:01 and HLA-C*16:01 in extra-articular manifestations was also significant. The frequency of HLA-Cw*6 was 6.7% and the allele HLA-B*27 was absent.

Conclusions

The HLA analysis in psoriatic arthritis showed a low frequency of HLA-C*06 and absence of HLA-B*27, different from the information reported for Caucasian population. These results also revealed other alleles of interest. Found differences could be related to the important racial mixing of our population.

Next-generation sequencing reveals additional HLA class I and class II alleles associated with type 1 diabetes and age at onset

Introduction

Type 1 diabetes is an autoimmune disease with an significant genetic component, played mainly by the HLA class II genes. Although evidence on the role of HLA class I genes in developing type 1 diabetes and its onset have emerged, current HLA screening is limited to determining DR3 and DR4 haplotypes. This study aimed to investigate the role of HLA genes on type 1 diabetes risk and age of onset by extensive typing.

Methods

This study included 115 children and young adults with type 1 diabetes for whom typing of HLA-A, -B, -C, -DRB1, -DRB3/4/5, -DQA1, -DQB1, -DPA1 and -DPB1 genes was conducted using Next Generation Sequencing.

Results

We observed that 13% of type 1 diabetes subjects had non-classical HLA haplotypes that predispose to diabetes. We also found that compared to type 1 diabetes subjects with classical HLA haplotypes, non-classical HLA subjects had a significantly higher frequency of HLA-B*39:06:02 (p-value=0.01) and HLA-C*07:02:01 (p-value=0.03) alleles, known to be involved in activating the immune response. Non-classical HLA subjects also presented peculiar clinical features compared to classical HLA subjects, such as multiple diabetic antibodies and the absence of other autoimmune diseases (i.e., coeliac disease and thyroiditis). We also observed that subjects with early onset had a higher frequency of DQ2/DQ8 genotype than late-onset individuals. Moreover, subjects with late-onset had a higher frequency of alleles HLA-B*27 (p-value=0.003), HLA-C*01:02:01 (p-value=0.027) and C*02:02:02 (p-value=0.01), known to be associated with increased protection against viral infections.

Discussion

This study reveals a broader involvement of the HLA locus in the development and onset of type 1 diabetes, providing insights into new possible disease prevention and management strategies.

Genome‑wide association study and polygenic risk scores predict psoriasis and its shared phenotypes in Taiwan

Psoriasis is a chronic inflammatory dermatological disease, and there is a lack of understanding of the genetic factors involved in psoriasis in Taiwan. To establish associations between genetic variations and psoriasis, a genome‑wide association study was performed in a cohort of 2,248 individuals with psoriasis and 67,440 individuals without psoriasis. Using the ingenuity pathway analysis software, biological networks were constructed. Human leukocyte antigen (HLA) diplotypes and haplotypes were analyzed using Attribute Bagging (HIBAG)‑R software and chi‑square analysis. The present study aimed to assess the potential risks associated with psoriasis using a polygenic risk score (PRS) analysis. The genetic association between single nucleotide polymorphisms (SNPs) in psoriasis and various human diseases was assessed by phenome‑wide association study. METAL software was used to analyze datasets from China Medical University Hospital (CMUH) and BioBank Japan (BBJ). The results of the present study revealed 8,585 SNPs with a significance threshold of P<5x10‑8, located within 153 genes strongly associated with the psoriasis phenotype, particularly on chromosomes 5 and 6. This specific genomic region has been identified by analyzing the biological networks associated with numerous pathways, including immune responses and inflammatory signaling. HLA genotype analysis indicated a strong association between HLA‑A*02:07 and HLA‑C*06:02 in a Taiwanese population. Based on our PRS analysis, the risk of psoriasis associated with the SNPs identified in the present study was quantified. These SNPs are associated with various dermatological, circulatory, endocrine, metabolic, musculoskeletal, hematopoietic and infectious diseases. The meta‑analysis results indicated successful replication of a study conducted on psoriasis in the BBJ. Several genetic loci are significantly associated with susceptibility to psoriasis in Taiwanese individuals. The present study contributes to our understanding of the genetic determinants that play a role in susceptibility to psoriasis. Furthermore, it provides valuable insights into the underlying etiology of psoriasis in the Taiwanese community.

A Review of MicroRNAs and lncRNAs in Atherosclerosis as Well as Some Major Inflammatory Conditions Affecting Atherosclerosis

It is generally accepted that atherosclerosis is a chronic inflammatory disease. The link between atherosclerosis and other inflammatory diseases such as psoriasis, type 2 diabetes mellitus (T2DM), and rheumatoid arthritis (RA) via metabolic, inflammatory, and immunoregulatory pathways is well established. The aim of our review was to summarize the associations between selected microRNAs (miRs) and long non-coding RNAs (lncRNAs) and atherosclerosis, psoriasis, T2DM, and RA. We reviewed the role of miR-146a, miR-210, miR-143, miR-223, miR-126, miR-21, miR-155, miR-145, miR-200, miR-133, miR-135, miR-221, miR-424, let-7, lncRNA-H19, lncRNA-MEG3, lncRNA-UCA1, and lncRNA-XIST in atherosclerosis and psoriasis, T2DM, and RA. Extracellular vesicles (EVs) are a method of intracellular signal transduction. Their function depends on surface expression, cargo, and the cell from which they originate. The majority of the studies that investigated lncRNAs and some miRs had relatively small sample sizes, which limits the generalizability of their findings and indicates the need for more research. Based on the studies reviewed, miR-146a, miR-155, miR-145, miR-200, miR-133, and lncRNA-H19 are the most promising potential biomarkers and, possibly, therapeutic targets for atherosclerosis as well as T2DM, RA, and psoriasis.

Imaging Approach in the Diagnostics and Evaluation of the Psoriasis Plaque: A Preliminary Study and Literature Review

(1) Background: the aim of the study was to demonstrate its usefulness in the field of imaging evaluation of plaque morphology in psoriasis vulgaris, with an emphasis on the use of confocal microscopy and other advanced skin-imaging techniques. (2) Methods: we conducted a prospective study over two years (July 2022-April 2024), on patients diagnosed with moderate or severe psoriasis vulgaris, treated in the dermatology department of our institution. We selected 30 patients, of whom 15 became eligible according to the inclusion and the exclusion criteria. A total of 60 psoriasis plaques were analyzed by dermatoscopy using a Delta 30 dermatoscope and Vidix 4.0 videodermoscope (VD), by cutaneous ultrasound (US) using a high-resolution 20 MHz linear probe, and by confocal microscopy, along with histopathological analysis. (3) Results: the study included fifteen patients with vulgar psoriasis, diagnosed histopathologically, of whom six were women and nine were men, with an average age of 55. Between two and six plaques per patient were selected and a total of sixty psoriasis plaques were analyzed by non-invasive imaging techniques. Twelve lesions were analyzed with ex vivo fluorescence confocal microscopy (FCM), compared to histology. US showed that the hyperechoic band and the lack of damage to the subcutaneous tissue were the most common criteria. The epidermis and dermis were found to be thicker in the area of psoriasis plaques compared to healthy skin. Dermatoscopy showed that the specific aspect of psoriasis plaques localized on the limbs and trunk was a lesion with an erythematous background, with dotted vessels with regular distribution on the surface and covered by white scales with diffuse distribution. The presence of bushy vessels with medium condensation was the most frequently identified pattern on VD. Good correlations were identified between the histological criteria and those obtained through confocal microscopy. (4) Conclusions: the assessment and monitoring of patients with psoriasis vulgaris can be conducted in a more complete and all-encompassing manner by incorporating dermatoscopy, ultrasonography, and confocal microscopy in clinical practice.

Clinical pharmacokinetics and pharmacodynamics of oral systemic nonbiologic therapies for psoriasis patients

INTRODUCTION

Psoriasis is a chronic inflammatory immune condition. Treatments for psoriasis vary with disease severity, ranging from topicals to systemic biologic agents. The pharmacokinetic (PK) and pharmacodynamic (PD) properties of these therapies establish drug efficacy, toxicity, and optimal dosing to ensure therapeutic drug levels are sustained and adverse effects are minimized.

AREAS COVERED

A literature search was performed on PubMed, Google Scholar, and Ovid MEDLINE for PK and PD, efficacy, and safety data regarding oral systemic nonbiologic therapies utilized for moderate-to-severe plaque psoriasis. The findings were organized into sections for each drug: oral acitretin, methotrexate, cyclosporine, apremilast, tofacitinib, and deucravacitinib.

EXPERT OPINION

Some psoriasis patients may not respond to initial therapy. Ongoing research is evaluating genetic polymorphisms that may predict an improved response to specific medications. However, financial and insurance barriers, as well as limited genetic polymorphisms correlated with treatment response, may restrict the implementation of genetic testing necessary to personalize treatments. How well psoriasis patients adhere to treatment may contribute greatly to variation in response. Therapeutic drug monitoring may help patients adhere to treatment, improve clinical response, and sustain disease control.

The Role of Epigenetic Factors in the Pathogenesis of Psoriasis

Psoriasis is a chronic inflammatory skin disease, the prevalence of which is increasing. Genetic, genomic, and epigenetic changes play a significant role in the pathogenesis of psoriasis. This review summarizes the impact of epigenetics on the development of psoriasis and highlights challenges for the future. The development of epigenetics provides a basis for the search for genetic markers associated with the major histocompatibility complex. Genome-wide association studies have made it possible to link psoriasis to genes and therefore to epigenetics. The acquired knowledge may in the future serve as a solid foundation for developing newer, increasingly effective methods of treating psoriasis. In this narrative review, we discuss the role of epigenetic factors in the pathogenesis of psoriasis.

Functional MICA Variants Are Differentially Associated with Immune-Mediated Inflammatory Diseases

As the principal ligand for NKG2D, MICA elicits the recruitment of subsets of T cells and NK cells in innate immunity. MICA gene variants greatly impact the functionality and expression of MICA in humans. The current study evaluated whether MICA polymorphisms distinctively influence the pathogenesis of psoriasis (PSO), rheumatoid arthritis (RA), and systemic lupus erythematosus (SLE) in Taiwanese subjects. The distributions of MICA alleles and levels of serum soluble NKG2D were compared between healthy controls and patients with PSO, RA, and SLE, respectively. The binding capacities and cell surface densities of MICA alleles were assessed by utilizing stable cell lines expressing four prominent Taiwanese MICA alleles. Our data revealed that MICA*010 was significantly associated with risks for PSO and RA (PFDR = 1.93 × 10-15 and 0.00112, respectively), while MICA*045 was significantly associated with predisposition to SLE (PFDR = 0.0002). On the other hand, MICA*002 was associated with protection against RA development (PFDR = 4.16 × 10-6), while MICA*009 was associated with a low risk for PSO (PFDR = 0.0058). MICA*002 exhibited the highest binding affinity for NKG2D compared to the other MICA alleles. Serum concentrations of soluble MICA were significantly elevated in SLE patients compared to healthy controls (p = 0.01). The lack of cell surface expression of the MICA*010 was caused by its entrapment in the endoplasmic reticulum. As a prevalent risk factor for PSO and RA, MICA*010 is deficient in cell surface expression and is unable to interact with NKG2D. Our study suggests that MICA alleles distinctively contribute to the pathogenesis of PSO, RA, and SLE in Taiwanese people.

Pediatric psoriasis: Understanding pathological conditions and advances in treatment

Psoriasis is a long-lasting skin disease that primarily affects the skin, nails, and joints and is characterized by inflammation. Genetic factors contribute to its development and environmental triggers can worsen symptoms. Pathologically, psoriasis is characterized by uncontrolled keratinocyte proliferation and abnormal differentiation, and histological features include acanthosis with inflammatory cell infiltration and neovascularization. Psoriasis often starts in childhood, with about one-third of cases beginning during this time. Its prevalence steadily increases from the ages of 1 to 18 years in a linear fashion. Young people with psoriasis often require treatment throughout their childhood and adolescence, and into adulthood. However, prolonged treatment may increase the risk of complications and adverse events, so it is important to adopt an effective treatment approach that minimizes this risk. In addition, psoriasis is often associated with various comorbidities that may place a great burden on the physical and mental health of the children beyond those due to psoriasis itself. To ensure good long-term health outcomes, individuals with psoriasis should undergo regular screening. Treatment should be provided not only for skin lesions, but also for any comorbidities; however, currently there is not enough evidence on the treatment of pediatric psoriasis and no globally agreed-on guidelines exist for treating psoriasis in children. This article describes the etiology, clinical symptoms, and disease burden of pediatric psoriasis, the pathological conditions and diagnosis of plaque psoriasis, psoriatic arthritis, and generalized pustular psoriasis, and the available treatments for these conditions in Japan.

Immune cells in the epithelial immune microenvironment of psoriasis: emerging therapeutic targets

Psoriasis is a chronic autoimmune inflammatory disease characterized by erroneous metabolism of keratinocytes. The development of psoriasis is closely related to abnormal activation and disorders of the immune system. Dysregulated skin protective mechanisms can activate inflammatory pathways within the epithelial immune microenvironment (EIME), leading to the development of autoimmune-related and inflammatory skin diseases. In this review, we initially emphasized the pathogenesis of psoriasis, paying particular attention to the interactions between the abnormal activation of immune cells and the production of cytokines in psoriasis. Subsequently, we delved into the significance of the interactions between EIME and immune cells in the emergence of psoriasis. A thorough understanding of these immune processes is crucial to the development of targeted therapies for psoriasis. Finally, we discussed the potential novel targeted therapies aimed at modulating the EIME in psoriasis. This comprehensive examination sheds light on the intricate underlying immune mechanisms and provides insights into potential therapeutic avenues of immune-mediated inflammatory diseases.

Five-year Maintenance of Clinical Response and Consistent Safety Profile for Guselkumab in Asian patients with Psoriasis from VOYAGE 1 and VOYAGE 2

INTRODUCTION

Guselkumab is a human monoclonal antibody against IL-23 used in the treatment of moderate-to-severe psoriasis. This post-hoc analysis evaluated the efficacy and safety of guselkumab in the Asian subpopulation of VOYAGE 1 and VOYAGE 2 through 5 years.

METHODS

The proportions of guselkumab-treated Asian patients (VOYAGE 1 and 2) achieving Psoriasis Area and Severity Index (PASI) 90 and PASI 100, Investigator's Global Assessment (IGA) scores of 0/1 and 0, and Dermatology Life Quality Index (DLQI) scores of 0/1 (week 100 through week 252) were assessed. Non-responders were patients who met the treatment failure rules. Efficacy endpoints were analyzed using the as-observed methodology (no missing data imputation) for both studies and using non-responder imputation (for patients with any missing data) in VOYAGE 1. Safety outcomes were based on pooled data through week 252.

RESULTS

Response rates through week 252 for 199 Asian patients in the guselkumab group in VOYAGE 1 and VOYAGE 2, respectively, were 76.8% and 80.6% (PASI 90), 26.8% and 38.7% (PASI 100), 64.3% and 87.1% (IGA 0/1), and 26.8% and 45.2% (IGA 0). DLQI (0/1) at week 252 was achieved by 52.7% of patients in VOYAGE 1 and 61.3% in VOYAGE 2, while DLQI (0) at week 252 was achieved by 32.7% of patients in VOYAGE 1 and 40.3% in VOYAGE 2. The safety profile was similar to the global population and remained consistent through 5 years. Asian patients were followed for a total of 814 patient-years (PY). Over 85% of the guselkumab-treated patients continued treatment through week 264. The rate of serious adverse events (AEs) at week 252 was 3.07/100 PY. Rates of AEs of interest were low: serious infections, 0.74/100 PY; nonmelanoma skin cancer (NMSC), no patients; malignancies other than NMSC, 0.12/100 PY; and no major adverse cardiovascular events (MACE).

CONCLUSION

These analyses confirm a continuous response over 5 years, indicating that guselkumab shows therapeutic longevity in Asian patients requiring long-term treatment for moderate-to-severe psoriasis.

TRIAL REGISTRATION

ClinicalTrials.gov identifiers: VOYAGE 1 [NCT02207231] and VOYAGE 2 [NCT02207244].

Oxidative Stress and Potential Antioxidant Therapies in Vitiligo: A Narrative Review

Vitiligo is a chronic skin disorder characterised by the loss of melanocytes and subsequent skin depigmentation. Although many theories have been proposed in the literature, none alone explains the pathogenesis of vitiligo. Oxidative stress has been identified as a potential factor in the pathogenesis of vitiligo. A growing body of evidence suggests that antioxidant therapies may offer a promising approach to managing this condition. This review summarises the potential mechanisms of oxidative stress and the types of melanocyte death in vitiligo. We also provide a brief overview of the most commonly studied antioxidants. Melanocytes in vitiligo are thought to be damaged by an accumulation of reactive oxygen species to destroy the structural and functional integrity of their DNA, lipids, and proteins. Various causes, including exogenous and endogenous stress factors, an imbalance between prooxidants and antioxidants, disruption of antioxidant pathways, and gene polymorphisms, lead to the overproduction of reactive oxygen species. Although necroptosis, pyroptosis, ferroptosis, and oxeiptosis are newer types of cell death that may contribute to the pathophysiology of vitiligo, apoptosis remains the most studied cell death mechanism in vitiligo. According to studies, vitamin E helps to treat lipid peroxidation of the skin caused by psoralen ultra-violet A treatment. In addition, Polypodium leucotomos increased the efficacy of psoralen ultra-violet A or narrow-band ultraviolet B therapy. Our review provides valuable insights into the potential role of oxidative stress in pathogenesis and antioxidant-based supporting therapies in treating vitiligo, offering a promising avenue for further research and the development of effective treatment strategies.

Disentangling the complexity of psoriasis in the post-genome-wide association era

In recent years, genome-wide association studies (GWAS) have been instrumental in unraveling the genetic architecture of complex diseases, including psoriasis. The application of large-scale GWA studies in psoriasis has illustrated several associated loci that participate in the cutaneous inflammation, however explaining a fraction of the disease heritability. With the advent of high-throughput sequencing technologies and functional genomics approaches, the post-GWAS era aims to unravel the functional mechanisms underlying the inter-individual variability in psoriasis patients. In this review, we present the key advances of psoriasis GWAS in under-represented populations, rare, non-coding and structural variants and epistatic phenomena that orchestrate the interplay between different cell types. We further review the gene-gene and gene-environment interactions contributing to the disease predisposition and development of comorbidities through Mendelian randomization studies and pleiotropic effects of psoriasis-associated loci. We finally examine the holistic approaches conducted in psoriasis through system genetics and state-of-the-art transcriptomic analyses, discussing their potential implication in the expanding field of precision medicine and characterization of comorbidities.

Evidence-based modalities in the management of Psoriasis and Psoriatic arthritis

Psoriasis is a waxing and waning skin disorder, often associated with a plethora of co-morbidities, including psoriatic arthritis (PsA), a severe form of chronic inflammatory arthritis. All forms of psoriasis and PsA are immune-mediated diseases where the patient's immune system is overactive in the production of certain factors that stimulate and activate the function of certain immune cells. Recent evidence has uncovered an important role for cell-mediated immunity in the aetiology and course of psoriasis and PsA, with a critical role played by the pro-inflammatory IL-23/TH17 axis. Taken together, these new lines of evidence suggest new and improved therapeutic interventions for patients with psoriasis and PsA. The hypothesis-driven process of inquiry of the best available evidence and its implication, application and evaluation in the context of clinical practice pertains to the meta-science of evidence-based health care (EBHC). EBHC consists in the initial step of research synthesis and generation of the systematic review of the best available evidence, estimated both qualitatively and quantitatively (i.e., meta-analysis). Evidence-based decision-making, a process driven and controlled by the expertise of the clinician and by the clinical needs and personal wants of the patient, is the principal, most timely and critical aspect of evidence-based practice. Recent and systematic reviews for the treatment of psoriasis and PsA consistently updated for emerging new and revised data (i.e., living systematic reviews) confirm the efficacy and the effectiveness of methotrexate (MTX) in containing and controlling psoriasis. The outcomes of MTX intervention for PsA remain mixed and inconclusive.

A partitioned 88-loci psoriasis genetic risk score reveals HLA and non-HLA contributions to clinical phenotypes in a Newfoundland psoriasis cohort

Psoriasis is an immune-mediated inflammatory skin disease typically characterized by erythematous and scaly plaques. It affects 3% of the Newfoundland population while only affecting 1.7% of the general Canadian population. Recent genome-wide association studies (GWAS) in psoriasis have identified more than 63 genetic susceptibility loci that individually have modest effects. Prior studies have shown that a genetic risk score (GRS) combining multiple loci can improve psoriasis disease prediction. However, these prior GRS studies have not fully explored the association of GRS with patient clinical characteristics. In this study, we calculated three types of GRS: one using all known GWAS SNPs (GRS-ALL), one using a subset of SNPs from the HLA region (GRS-HLA), and the last using non-HLA SNPs (GRS-noHLA). We examined the relationship between these GRS and a number of psoriasis features within a well characterized Newfoundland psoriasis cohort. We found that both GRS-ALL and GRS-HLA were significantly associated with early age of psoriasis onset, psoriasis severity, first presentation of psoriasis at the elbow or knee, and the total number of body locations affected, while only GRS-ALL was associated with a positive family history of psoriasis. GRS-noHLA was uniquely associated with genital psoriasis. These findings clarify the relationship of the HLA and non-HLA components of GRS with important clinical features of psoriasis.

Genetic and Molecular Distinctions Between Axial Psoriatic Arthritis and Radiographic Axial Spondyloarthritis: Post Hoc Analyses from Four Phase 3 Clinical Trials

INTRODUCTION

Emerging evidence suggests psoriatic arthritis (PsA) with axial involvement (axPsA) and radiographic axial spondyloarthritis (r-axSpA) may possibly represent distinct disorders, with some differing clinical manifestations, genetic associations, and radiographic findings. Moreover, axPsA and r-axSpA may respond differently to therapies: guselkumab (interleukin [IL]-23p19 subunit inhibitor [i]) and ustekinumab (IL-12/23p40i) demonstrated improvements in axial symptoms in patients with PsA; however, neither risankizumab (IL-23p19i) nor ustekinumab demonstrated efficacy versus placebo in patients with r-axSpA. Current analyses aim to further understand potential molecular distinctions between axPsA and r-axSpA and examine the pharmacodynamic effects of guselkumab in patients with axPsA and those with PsA without axial involvement (non-axPsA).

METHODS

Post hoc analyses utilized biomarker data from blood and serum samples collected from a subset of participants in phase 3 studies of ustekinumab in r-axSpA and guselkumab in PsA (DISCOVER-1 and DISCOVER-2). Participants with axPsA were identified by investigator-verified sacroiliitis (imaging-confirmed) and axial symptoms. HLA mapping, serum cytokine analysis, and whole-blood RNA sequencing were conducted.

RESULTS

Relative to r-axSpA, patients with axPsA had a lower prevalence of HLA-B27, HLA-C01, and HLA-C02 alleles and a higher prevalence of HLA-B13, HLA-B38, HLA-B57, HLA-C06, and HLA-C12 alleles. Compared with r-axSpA, patients with axPsA had elevated baseline levels of serum IL-17A and IL-17F cytokines, enrichment of IL-17 and IL-10 pathway-associated genes, and neutrophil gene markers. Across axPsA and non-axPsA cohorts, reductions in cytokine levels and normalization of pathway-associated gene expression with guselkumab treatment were comparable.

CONCLUSION

The differences in HLA genetic associations, serum cytokines, and enrichment scores support the concept that axPsA and r-axSpA may be distinct disorders. The comparable pharmacodynamic effects of guselkumab on cytokine levels and pathway-associated genes observed in patients with axPsA and non-axPsA are consistent with demonstrated clinical improvements across PsA cohorts. These findings contribute to the understanding of potential genetic and molecular distinctions between axPsA and r-axSpA.

TRIAL REGISTRATION

ClinicalTrials.gov identifiers, NCT03162796, NCT0315828, NCT02437162, and NCT02438787.

The Association of HLA Alleles and Haplotypes with Age of Disease Onset in Pakistani Psoriatic Patients

INTRODUCTION

The human leukocyte antigen (HLA) region on chromosome 6p21 is well known to carry the most important genetic factors in susceptibility to psoriasis. Different HLA alleles and haplotypes have been reported to be associated with psoriasis in different populations. Psoriasis has a variable age of onset and, based on this, it can be classified into two types; type I with age of onset before 40 years of age and type II with age of onset after 40 years of age. The objective of this study was to determine the association of HLA class I and class II alleles and haplotypes with disease and stratification using age of onset in Pakistani psoriatic patients.

METHODS

A group of 603 individuals (326 cases and 277 controls) were analyzed for HLA class I and II alleles and haplotype association by sequence specific PCR. The association was further analyzed according to the age of onset of the patients.

RESULTS

We found that HLA alleles B*57 and Cw*06:02, DQB1*03:03:02 are strongly associated with early onset psoriasis, while alleles B*15, DRB1*13:02 and DQB1*03:03:02 are associated with late-onset psoriasis. Cw*06:02 allele was not associated with late-onset psoriasis patients. Allele DQB1*03:03:02 had the highest odds ratio in all patients. We found a novel association specifically with late-onset psoriasis samples with the haplotype HLA-A*11; B*15; Cw*04; DRB1*15; DQB1*05 (Pc = 3.60 × 10-7). We also found strong association with previously reported extended haplotype EH-57.1: HLA-B*57; Cw*06:02; DRB1*07:01; DQB1*03:03:02 in all our patients (Pc = 8.34 × 10-07).

CONCLUSION

Our results show that different HLA class I and II alleles and haplotypes are associated with psoriasis at different age of onset. In this study, we have reported novel alleles and haplotype association with late-onset psoriasis. Our data confirm the previous strong associations with HLA alleles and haplotypes and also reports novel alleles and haplotype association in Pakistani psoriasis patients.

HLA-C Genotyping Reveals Haplotype C*07 as a Potential Biomarker of Late Psoriasis Onset in Moroccan Patients

Psoriasis still has an unknown etiology. Genetic predisposition shows the association between HLA-Cw6 allele and psoriasis. Although biotherapies have been proven effective in psoriasis treatment, methotrexate (MTX) is still used as a first-line systemic therapy due to its efficacy/affordability, but the differential response to MTX is mostly related to interindividual genetic variability and remains an issue. Our study aimed to analyze HLA-C allele frequencies in a sample of Moroccan psoriatic patients and assess the therapeutic response to MTX. Whole blood of 54 Moroccan psoriatic patients was collected and DNA was extracted. Patients' HLA-C locus was genotyped by PCR-SSO. Results were analyzed with Luminex xMAP Technology and Match-it DNA Evolution 3.4. HLA-C typing results of 77 sex- and age-matched unrelated non-psoriatic healthy subjects were included. We observed no difference in the allelic distribution of HLA-C between patients and healthy controls, suggesting that none of the HLA-C alleles were significantly associated with psoriasis. Moreover, the HLA-C*07 allele was associated with a late age at disease onset (>30 years old) (p = 0.007). No statistically significant association was found between HLA-C allele expression and response to MTX, despite a higher frequency of HLA-C*06 in responders compared to non-responders. Thus, HLA-C*07 could be a biomarker of late psoriasis onset in the Moroccan population.

Targeting IL-17A for the treatment of pustular psoriasis: a comprehensive review

INTRODUCTION

Pustular psoriasis (PP) is a rare subtype of psoriasis. Overall, the growing evidence - in particular for acute generalized PP (GPP) - supports that it is a separate entity with a specific pathogenetic pathway. Interleukin (IL)-17/T-helper 17 (Th17) axis involvement may play an important role in the pathophysiology of PP. Biologicals, often required to achieve clinical remission, have changed the treatment of PP.

AREAS COVERED

We provide the reader with an overview of all the available evidence on the use of the antibody-based therapy targeting IL-17A in patients with PP.

EXPERT OPINION

Although papers reported in this review do not provide definitive evidence (due to methodological limitations) to support the use of IL-17 inhibitors as potential first-line for the treatment of PP, based on our own experience and according to most of the reported literature, targeting IL-17A, may represent the best therapeutical approach in this peculiar clinical spectrum of psoriasis.

Variations in genetics, biology, and phenotype of cutaneous disorders in skin of color - Part I: Genetic, biologic, and structural differences in skin of color

Skin of color (SOC) populations include those who identify as Black/African, Hispanic/Latinx, Asian/Pacific Islander, American Indian/Native Alaskan, Indigenous Australian, Middle Eastern, biracial/multiracial, or non-White; this list is far from exhaustive and may vary between and within cultures. Recent genetic and immunological studies have suggested that cutaneous inflammatory disorders (atopic dermatitis, psoriasis, and hidradenitis suppurativa) and malignancies (melanoma, basal cell carcinoma, and cutaneous T-cell lymphoma) may have variations in their immunophenotype among SOC. Additionally, there is growing recognition of the substantial role social determinants of health play in driving health inequalities in SOC communities. It is critically important to understand that social determinants of health often play a larger role than biologic or genetic factors attributed to "race" in health care outcomes. Herein, we describe the structural, genetic, and immunological variations and the potential implications of these variations in populations with SOC. This article underscores the importance of increasing the number of large, robust genetic studies of cutaneous disorders in SOC to create more targeted, effective therapies for this often underserved and understudied population. Part II of this CME will highlight the clinical differences in the phenotypic presentation of and the health disparities associated with the aforementioned cutaneous disorders in SOC.

Human leukocyte antigen system associations in Malassezia-related skin diseases

BACKGROUND

The human leukocyte antigen system (HLA) is divided into two classes involved in antigen presentation: class I presenting intracellular antigens and class II presenting extracellular antigens. While susceptibility to infections is correlated with the HLA system, data on associations between HLA genotypes and Malassezia-related skin diseases (MRSD) are lacking. Thus, the objective of this study was to investigate associations between HLA alleles and MRSD.

MATERIALS AND METHODS

Participants in The Danish Blood Donor Study (2010-2018) provided questionnaire data on life style, anthropometric measures, and registry data on filled prescriptions. Genotyping was done using Illumina Infinium Global Screening Array, and HLA alleles were imputed using the HIBAG algorithm. Cases and controls were defined using filled prescriptions on topical ketoconazole 2% as a proxy of MRSD. Logistic regressions assessed associations between HLA alleles and MRSD adjusted for confounders and Bonferroni corrected for multiple tests.

RESULTS

A total of 9455 participants were considered MRSD cases and 24,144 participants as controls. We identified four risk alleles B*57:01, OR 1.19 (95% CI: 1.09-1.31), C*01:02, OR 1.19 (95% CI: 1.08-1.32), C*06:02, OR 1.14 (95% CI: 1.08-1.22), and DRB1*01:01, OR 1.10 (95% CI: 1.04-1.17), and two protective alleles, DQB1*02:01, OR 0.89 (95% CI: 0.85-0.94), and DRB1*03:01, OR 0.89 (95% CI: 0.85-0.94).

CONCLUSION

Five novel associations between HLA alleles and MRSD were identified in our cohort, and one previous association was confirmed. Future studies should assess the correlation between Malassezia antigens and antigen-binding properties of the associated HLA alleles.

Outcomes of Biologic Use in Asian Compared with Non-Hispanic White Adult Psoriasis Patients from the CorEvitas Psoriasis Registry

INTRODUCTION

Real-world data are limited comparing Asian and White patients with psoriasis using biologic therapy. This study compared the 6-month effectiveness of biologic therapy between Asian and White plaque patients with psoriasis in the CorEvitas Psoriasis Registry.

METHODS

Analyses included biologic initiations and 6-month follow-up visits from self-identified Asian (n = 293) and White (n = 2314) patients in the USA/Canada (4/2015-4/2020). Outcomes included: Psoriasis Area Severity Index (PASI) 75, disease activity measures [body surface area (BSA) ≤ 1, BSA ≤ 3, PASI90, PASI100, Investigator's Global Assessment (IGA) 0/1], and patient-reported outcomes [Dermatology Life Quality Index (DLQI) 0/1, itch, fatigue, skin pain, EuroQoL visual analog scale (EQ-VAS), patient global assessment, Work Productivity Activity and Impairment (WPAI) domains]. Unadjusted regression models were used to calculate odds ratios (OR) and 95% confidence intervals (CI) for achievement of binary outcomes and difference in mean change in continuous outcomes (β, 95% CI) at 6 months, followed by adjustment for age, sex, body mass index, alcohol, smoking, health insurance, education, comorbidities, scalp psoriasis morphology, psoriatic arthritis, biologic class, previous biologics, and baseline outcome value.

RESULTS

Asians had lower proportions of women (32.8% versus 49.1%) and obesity (27.3% versus 54.5%), and higher proportions on Medicaid (19.9% versus 8.8%), graduated college (50.9% versus 40.1%) and never smoked (67.1% versus 44.1%). In unadjusted analyses, Asians had 52% higher odds of achieving PASI75 versus White patients (OR 1.52; 95% CI 1.15, 2.02). After adjustment, the association was attenuated (OR 1.11; 0.81, 1.52). Secondary outcomes experienced similar patterns except for DLQI: Asians had 33% lower odds of achieving DLQI 0/1 in both the unadjusted (OR 0.67; 0.50, 0.90) and adjusted (OR 0.67; 0.49, 0.92) models.

CONCLUSION

Unadjusted differences in biologic therapy effectiveness between Asians compared with White patients were likely explained by differences in demographic, lifestyle, and psoriatic disease characteristics between groups. However, Asians still experienced lesser improvements in skin-related quality of life, even after adjustment.

Psoriasis Patients with Specific HLA-Cw Alleles and Lower Plasma IL-17 Level Show Improved Response to Topical Lindioil Treatment

Purpose

Lindioil, a medicine refined from indigo naturalis (a herb used in Chinese medicine), is effective in treating severe psoriasis; however, responses vary across individual patients. We aim to investigate genetic predispositions associated with treatment response to topical Lindioil among patients with psoriasis and correlations with plasma cytokine patterns.

Patients and Methods

We enrolled 72 psoriasis patients treated with Lindioil ointment and analyzed the human leukocyte antigen class C (HLA-Cw) genotypes and plasma cytokine expression patterns. We developed regression models of treatment response, defined as Psoriasis Area and Severity Index (PASI) 75, to examine correlations among HLA-Cw alleles, cytokine levels, and treatment response to Lindioil.

Results

Patients harboring HLA-Cw*06:02 were significantly more likely to respond to Lindioil (P = 0.02, odds ratio [OR]: 6.88), whereas Lindoil was ineffective in those harboring HLA-Cw*01:02 (P = 0.01, OR: 0.28). Patients who were HLA-Cw*06:02-positive or HLA-Cw*01:02-negative had better PASI scores and body surface area (BSA) improvement (73.3% vs 44.4%, P<0.001) following an 8-week treatment period. Psoriasis patients achieving PASI 75 after 8 weeks presented with lower baseline plasma interleukin-17 (IL-17) levels than those who did not achieve PASI 75 (PASI 75: 11.28 pg/mL vs PASI <75: 15.82 pg/mL, P = 0.05).

Conclusion

Our findings suggest that the presence of the HLA-Cw*06:02 or HLA-Cw*01:02 alleles and plasma IL-17 levels are predictive markers of treatment response to Lindioil ointment in patients with psoriasis.

Exacerbation of Psoriasis Following COVID-19 Vaccination: Report From a Single Center

The temporal association had been reported between vaccination and exacerbation of psoriasis, and episodes of psoriasis flare-up have recently been attributed to COVID-19 vaccines. We recruited 32 unimmunized controls and 51 vaccinated psoriasis patients, 49 of whom were under biological therapy, with regular clinic visits receiving a total of 63 shots of vaccines, including 30 doses of Moderna mRNA-1273 and 33 doses of AstraZeneca-Oxford AZD1222. Fifteen episodes of exacerbation attacked within 9.3 ± 4.3 days, which is higher than two episodes in the control group (p = 0.047). The mean post-vaccination severity of the worsening episodes increased from PASI 3.1 to 8.0 (p < 0.001). Three patients showed morphologic change from chronic plaque-type to guttate psoriasis. Deterioration of psoriasis following COVID-19 vaccination was not associated with age, sex, disease duration, psoriatic arthritis, family history of psoriasis, history of erythroderma, current biologics use, comorbidities, vaccine types, human leukocyte antigen (HLA)-C genotypes, baseline PASI nor pre-vaccination PASI. For those who received two doses of vaccination, all but one patient aggravated after the first shot but not the second. The mechanism of psoriasis exacerbation in immunized individuals is unclear, but Th17 cells induced by COVID-19 vaccines may play a role. In the pandemic era, psoriasis patients and physicians should acknowledge the possibility of fluctuation of disease activity when vaccinated against COVID-19. Nevertheless, compared to a treatable dermatologic disease with rapid resolution of exacerbation, psoriasis patients who do not have contraindications to vaccination should benefit from COVID-19 vaccines in the prevention of severe COVID-19 infection and fatality.

Non-immune functions of inflammatory cytokines targeted by anti-psoriatic biologics: a review

PURPOSE

Psoriasis is an inflammatory disease characterized by skin thickening with silvery white desquamation due to dysregulated inflammatory pathways and elevated levels of inflammatory cytokines. Biologic agents targeting these inflammatory cytokines have brought about significant improvement in clearing psoriatic lesions in patients with moderate-to-severe psoriasis. Moreover, biologics exert both beneficial and detrimental effects on comorbidities in psoriasis, which include increased risk of cardiovascular events, metabolic syndrome, among other conditions. However, non-immune functions of cytokines targeted by biologics, and, hence, the potential risks and benefits of biologics for psoriasis to different organs/systems and comorbidities, have not been well elucidated.

RESULTS

This review summarizes current understanding of the pathogenesis of psoriasis-related comorbidities and emerging discoveries of roles of cytokines targeted in psoriasis treatment, including tumor necrosis factor α and interleukins 12, 23, and 17, aiming to complete the safety profile of each biologics and provide therapeutic implications on psoriasis-related comorbidities, and on diseases involving other organs or systems.