Serum cytokine profile in psoriasis-a case-control study in a tertiary care hospital from northern India

Cytokines in psoriasis: From pathogenesis to targeted therapy

Psoriasis is a multifactorial disease that affects 0.84% of the global population and it can be associated with disabling comorbidities. As patients present with thick scaly lesions, psoriasis was long believed to be a disorder of keratinocytes. Psoriasis is now understood to be the outcome of the interaction between immunological and environmental factors in individuals with genetic predisposition. While it was initially thought to be solely mediated by cytokines of type-1 immunity, namely interferon-γ, interleukin-2, and interleukin-12 because it responds very well to cyclosporine, a reversible IL-2 inhibitor; the discovery of Th-17 cells advanced the understanding of the disease and helped the development of biological therapy. This article aims to provide a comprehensive review of the role of cytokines in psoriasis, highlighting areas of controversy and identifying the connection between cytokine imbalance and disease manifestations. It also presents the approved targeted treatments for psoriasis and those currently under investigation.

Circulating inflammatory cytokines and psoriasis risk: A systematic review and meta-analysis

BACKGROUND

Psoriasis is a systemic immune-mediated chronic inflammatory skin disease; its systemic manifestations and periodic recurrence negatively affect a patient's quality of life. Inflammatory cytokines are known to have an important role in the onset and progression of psoriasis, however, data on the association between circulating inflammatory cytokines and psoriasis risk is inconclusive. Here, we explore the relevance of circulating proinflammatory factors to the pathogenesis of psoriasis using a meta-analysis.

OBJECTIVE

To explore the association between circulating levels of inflammatory factors and psoriasis to elucidate the mechanisms underlying psoriasis and improve clinical diagnosis and treatment.

METHODS

We systematically retrieved articles published in PubMed, EMBASE, the Cochrane Library and the Web of Science from the establishment of each database to January 2023. The standard mean difference (SMD) in cytokine levels of individuals with psoriasis and healthy controls was used to check for correlations between circulating inflammatory factor levels and psoriasis.

RESULTS

Fifty-seven studies, with data from 2838 patients, were retrieved and included in the meta-analysis. Eleven inflammatory factors were studied (circulating interleukin-2 (IL-2), IL-4, IL-12, IL-17, IL-18, IL-22, IL-23, IL-35, IL-36, transforming growth factor-beta (TGF-β) and gamma-interferon (IFN-γ)). Of these, IL-2 [SMD = 1.29 (95% CI: 0.61-1.97; P <0.001)], IL-17 [SMD = 0.71 (95% CI: 0.12-1.30; P = 0.018)], IL-18 [SMD = 1.27 (95% CI: 0.64-1.90; P <0.001)], and IFN-γ [SMD = 1.90 (95% CI: 1.27-2.52; P <0.001)] levels had significant correlations with psoriasis.

CONCLUSION

Increased serum concentrations of the circulating inflammatory cytokines IL-2, IL-17, IL-18 and IFN-γ were significantly correlated with psoriasis.

Cytokine alterations in psoriasis: an updated review

INTRODUCTION

Psoriasis is a chronic immune-mediated disease affecting 125 million people globally. It is characterized by erythematous plaques in the skin, covered by silvery scales. However, non-cutaneous manifestations (e.g., joint symptoms in psoriatic arthritis) and a high prevalence of other immune-mediated diseases such as inflammatory bowel diseases reflect its systemic nature. So far, research on psoriasis pathogenesis has improved our knowledge of the roles of the immune system, and cytokines play significant roles in immune responses.

AREAS COVERED

Herein, we review cytokine changes in psoriasis patients. Moreover, we will investigate the possible relationships between disease severity and cytokines alongside describing cytokine alterations in psoriasis patients with other comorbidities. Lastly, we will discuss the biologics and their effects on cytokines in psoriasis patients.

EXPERT OPINION

Psoriasis could develop various clinical types and clinical manifestations in people. It is an immune-mediated disease, and these manifestations are associated with different impaired cytokines. Imbalanced cytokines could lead to abnormal keratinocytes, neovascularization, and inflammation in psoriasis patients. So, a better understanding of the cytokine roles can help one choose a specific cytokine-targeting biologic to treat psoriasis. Moreover, these cytokines may be used as a severity marker for following up with these patients.

Evaluation of selected mechanisms of immune tolerance in psoriasis

Introduction

Psoriasis is an autoimmune disease with an excessively aberration of the Th17/Treg balance and deficiency of anti-inflammatory cytokines.

Aim

Evaluation of Treg markers expression in the lesional and perilesional psoriatic skin and serum anti-inflammatory cytokines in male psoriatic patients compared to healthy men.

Material and methods

Treg markers (FoxP3+, CD4, CTLA-4, CD25/IL-2R, CD39/ENTPD1, IL-7R/CD127, CD3) and tissue expression of protective cytokines (IL-10, IL-35, TGF-β) in the lesional and perilesional psoriatic skin from 33 male patients compared to 6 healthy skin samples were evaluated by immunohistochemistry. ELISA was used to assess serum IL-10, IL-35 and TGF-β levels.

Results

The serum levels of IL-35, IL-10 and TGF-β1 were higher in psoriatic patients than in controls but without any statistically significant relationship with PASI. The expressions of IL-35, CD4, IL-10, TGF-β1, CD3, FOXP3 and CD25/IL-2R were varied in different experimental groups (p < 0.05). The level of IL-35 was the lowest in psoriatic lesions (p < 0.05) compared to perilesional skin and to controls. CD4, IL-10 and TGF-β1 expressions were higher (p < 0.05) in perilesional skin than in lesions. TGF-β1 expression was decreased in psoriatic lesions compared to controls (p < 0.05). CD25/IL2R expression was increased in healthy skin compared to psoriatic skin (p < 0.05). FOXP3 expression was elevated in psoriatic skin compared to healthy and perilesional one. There was no difference between experimental groups in CTLA-4, IL7R/CD127 and CD39/ENTPD1 expression.

Conclusions

The differences between the levels of protective cytokines and expression of Treg markers might explain the inflammation development in psoriasis.

Variation at Interleukin-10 Locus Represents Susceptibility to Psoriasis in North Indian Population

BACKGROUND

IL-10 is an important pleiotropic, immunoregulatory and anti-inflammatory cytokine which plays a significant role in the pathogenesis of psoriasis.

OBJECTIVE

The aim of the present study was to determine whether the three polymorphic sites of the IL-10 gene, haplotype and serum level confer susceptibility to psoriasis.

METHOD

200 psoriatic patients and 200 controls were genotyped for three IL-10 polymorphic sites by ARMS polymerase chain reaction. Serum levels of IL -10 were measured by ELISA.

RESULTS

Our results demonstrated that polymorphism of IL-10 -592 C/A (adjusted* OR = 9.25; 95% CI =3.16- 27.06) and IL-10 1082 A/G (adjusted* OR = 4.28; (95% CI =1.46- 12.56) was found to be in association with increased risk of psoriasis while as IL- 10 819 C/T (adjusted* OR= 1.60; (95% CI = 0.65-3.95) polymorphism does not show any significant association with the risk of psoriasis. HT7 GTC haplotype is associated with increased risk of psoriasis. Serum levels of IL-10 were found to be significantly low in patients, as compared to controls with a non-significant correlation between serum IL-10 level and psoriasis severity.

CONCLUSION

IL-10 polymorphism imparted significant risk towards the development of psoriasis in North Indian population. Highlighting the role of IL-10 cytokine in the pathogenesis of psoriasis will help in the development of psoriasis management.

Prevalence of psoriatic arthritis in patients with psoriasis: A systematic review and meta-analysis of observational and clinical studies

BACKGROUND

Wide-ranging prevalence estimates of psoriatic arthritis (PsA) in patients with psoriasis have been reported.

OBJECTIVES

To assess the prevalence and incidence of PsA in patients with psoriasis.

METHODS

Two authors independently searched 3 databases for studies reporting on the prevalence or incidence of PsA in patients with psoriasis. A proportion meta-analysis was performed to calculate the pooled proportion estimates of PsA in patients with psoriasis.

RESULTS

A total of 266 studies examining 976,408 patients with psoriasis were included. Overall, the pooled proportion (95% confidence interval [CI]) of PsA among patients with psoriasis was 19.7% (95% CI, 18.5%-20.9%). In children and adolescents (<18 years of age), the pooled prevalence was 3.3% (95% CI, 2.1%-4.9%). The PsA prevalence was 22.7% (95% CI, 20.6%-25.0%) in European patients with psoriasis, 21.5% (95% CI, 15.4%-28.2%) in South American patients with psoriasis, 19.5% (95% CI, 17.1%-22.1%) in North American patients with psoriasis, 15.5% (95% CI, 0.009%-51.5%) in African patients with psoriasis, and 14.0% (95% CI, 95% CI, 11.7%-16.3%) in Asian patients with psoriasis. The prevalence of PsA was 23.8% (95% CI, 20.1%-27.6%) in studies in which the Classification Criteria for Psoriatic Arthritis were applied. The incidence of PsA among patients with psoriasis ranged from 0.27 to 2.7 per 100 person-years.

LIMITATIONS

Between-study heterogeneity may have affected the estimates.

CONCLUSIONS

We found that 1 in 4 patients with psoriasis have PsA. With the growing recognition of the Classification Criteria for Psoriatic Arthritis, more homogenous and comparable prevalence estimates are expected to be reported.

Correlation of IL-12, IL-22, and IL-23 in patients with psoriasis and metabolic syndrome. Preliminary report

BACKGROUND

Psoriasis is an autoimmune skin disease characterised by proliferation of keratinocytes, primarily due to cytokines Th1 and Th17. This profile is involved in pathogenesis of metabolic syndrome, a frequently found comorbidity in patients with psoriasis.

OBJECTIVE

In this study we determine the correlation of levels of pro-inflammatory cytokines TNF-α, IL-23, IL-12, and IL-22 in patients with psoriasis with and without metabolic syndrome and clinically healthy controls.

METHODS

We included 55 patients with plaque psoriasis: 30 with metabolic syndrome (PPMS), 25 without metabolic syndrome (PP), 15 healthy subjects (HS) and 15 with metabolic syndrome (MS). Quantification of serum levels of IL-12, TNF-α, IL-22, and IL-23 was done by ELISA.

RESULTS

We observed that serum levels of IL-12 were more elevated in PP group, while the lowest levels of TNF-α were seen in HS group. IL-22 was found to be higher in PP than in PPMS (p<0.05). PP patients with PASI scores rating as severe showed higher levels of IL-12. TNF-α level analysis showed significant differences in HS group compared with the others; levels of this cytokine were lower in patients with PP and moderate PASI scores than in MS group (p<0.05). We found no correlation between cytokine levels and psoriasis or between cytokines and PASI scores. In PP group, a positive correlation was observed between IL-23 and fasting glucose (r=0.432, p<0.05), as well as a negative correlation between IL-23, IL-22, and IL-12 versus waist circumference (r=-0.504, r=-0.556 and r=-0.511, respectively; p<0.05).

CONCLUSIONS

Psoriasis is not just a skin disorder, but rather a condition with systemic implications, with intervention of pro-inflammatory cytokines that contribute to metabolic syndrome and other comorbidities, which in turn increases the risk of developing cardiovascular disease.

Serum levels of TNF- α , IL-12/23 p40, and IL-17 in psoriatic patients with and without nail psoriasis: a cross-sectional study

Nail involvement has started playing a major role in the overall assessment and management of psoriatic disease. Biologics indicated for moderate to severe chronic plaque psoriasis are shown to be beneficial in nail disease. This study aimed to assess and compare the serum levels of TNF-α, IL-12/23 p40, and IL-17 in psoriatic patients with and without nail involvement. 52 consecutively selected patients with chronic plaque psoriasis were included in this cross-sectional study. Patients were studied and analyzed after they had been divided into 2 groups regarding the presence (n = 24) or not (n = 28) of nail psoriasis. The mean serum levels of TNF-α were significantly higher in the group of psoriatic patients with nail lesions compared to those without (t-test; 5.40 ± 1.17 versus 3.80 ± 1.63, P = 0.026). However, the median serum levels of both IL-12/23 p40 (Mann-Whitney; 92.52 (34.35-126.87) versus 150.68 (35.18-185.86), P = 0.297) and IL-17 (Mann-Whitney; 28.49 (0.00-28.49) versus 8.59 (0.00-8.59), P = 0.714) did not significantly differ between the 2 groups. These results confirm the important role of TNF-α in the pathogenesis of nail psoriasis and may suggest that anti-TNF agents could be more beneficial in psoriatic nail disease than agents targeting IL-12/23 p40 or IL-17 and its receptors.

Serum levels of TNF-α, IL-12/23p40, and IL-17 in plaque psoriasis and their correlation with disease severity

A case-control study was performed to assess the serum levels of TNF-α, IL-12/23p40, and IL-17 in patients with plaque psoriasis, compare them with healthy controls, and correlate them with disease severity, as represented by Psoriasis Area Severity Index (PASI). 32 consecutively selected, untreated patients with active, chronic plaque psoriasis were recruited and compared to 32 age- and sex-matched healthy controls. Serum cytokine levels were determined by solid phase sandwich enzyme linked immunosorbent assay (R&D Systems Europe, Ltd.). The mean serum levels of TNF-α were significantly higher in psoriatic patients compared to those of controls (Mann-Whitney U test; P = 0.000). However, the median serum levels of neither IL-12/23p40 nor IL-17 differ significantly between the 2 groups (Mann-Whitney U test; P = 0.968 and P = 0.311, resp.). No significant correlations were found between PASI and any of the cytokine serum levels (Spearman's rank test; P > 0.05). Despite the well-evidenced therapeutic efficacy of biologic agents targeting TNF-α, IL-12/23p40, and IL-17, serum levels of TNF-α, IL-12/23p40, and IL-17 do not seem to correlate with the severity of psoriatic skin disease in untreated patients, as represented by PASI. Further investigation may add more data on the pathogenetic cascade of psoriasis.

Immunological and histological evaluation of clinical samples from psoriasis patients treated with anti-CD6 itolizumab

Psoriasis is a chronic inflammatory disease with a prevalence of approximately 2-3% in the general population. The majority of diagnosed patients have plaque psoriasis, and about 20% have moderate-to-severe disease. Itolizumab, a new monoclonal antibody specific for the CD6 molecule mainly expressed on T lymphocytes, has demonstrated to inhibit in vitro ligand-induced proliferation and pro-inflammatory cytokine production. We assessed the immunological and histopathological effect of the antibody using clinical samples taken from 26 patients with moderate-to-severe psoriasis included in a clinical trial. The precursor frequency of lymphocytes activated with anti-CD2/CD3/CD28 beads, as well as the number of interferon (IFN)-γ-secreting T cells after stimulation, were measured at different time points of the study. Serum cytokine levels and anti-idiotypic antibody response to itolizumab were also evaluated. Additionally, lymphocyte infiltration and epidermis hyperplasia were studied in five patients. A significant reduction in T cell proliferation capacity and number of IFN-γ-producing T cells was found in treated patients. Serum levels of interleukin-6, tumor necrosis factor and IFN-γ showed an overall trend toward reduction. No anti-idiotypic antibody response was detected. A significant reduction in the epidermis hyperplasia was observed in analyzed patients. These results support the relevance of the CD6 molecule as a therapeutic target for the treatment of this disease.

Polymorphisms in the TNF-α and IL-10 gene promoters and risk of psoriasis and correlation with disease severity

Several cytokines were assumed to play an essential role in the induction and the pathogenesis of psoriasis. The aim of this work was to investigate the role of TNF-α-308 and IL-10-1082 polymorphisms and their serum levels in the pathogenesis of psoriasis and determine their relation to disease severity. 110 Psoriasis patients and 120 healthy volunteers were genotyped for TNF-α-308 and IL-10-1082 polymorphism by polymerase chain reaction. Serum level of TNF-α and IL-10 were measured by ELISA. Our study demonstrated an association of IL-10-1082 polymorphism and psoriasis and between TNF α-308 polymorphism and psoriasis disease and severity. Serum TNF α increased in patients, while serum IL-10 decreased in patients with significant correlation between serum TNF-α and psoriasis severity. These results indicated that TNF-α-308 and IL-10-1082 polymorphisms imparted significant risk towards the development of psoriasis.