Peripheral Blood Of Psoriatic Patients Research Articles

Thrombosis in Psoriasis: Cutaneous Cytokine Production as a Potential Driving Force of Haemostatic Dysregulation and Subsequent Cardiovascular Risk.

Psoriasis (PsO) is a common T cell-mediated inflammatory disorder of the skin with an estimated prevalence of 2%. The condition manifests most commonly as erythematous plaques covered with scales. The aetiology of PsO is multifactorial and disease initiation involves interactions between environmental factors, susceptibility genes, and innate and adaptive immune responses. The underlying pathology is mainly driven by interleukin-17. In addition, various inflammatory mediators from specific T helper (TH) cell subsets, namely TH1, TH17, and TH22, are overexpressed in cutaneous lesions and may also be detected in the peripheral blood of psoriatic patients. Moreover, these individuals are also at greater risk, compared to the general population, of developing multiple comorbid conditions. Cardiovascular disease (CVD) has been recognised as a prominent comorbidity of PsO. A potential mechanism contributing to this association may be the presence of a hypercoagulable state in these individuals. Inflammation and coagulation are closely related. The presence of chronic, low-grade systemic inflammation may promote thrombosis – one of the major determinants of CVD. A pro-inflammatory milieu may induce the expression of tissue factor, augment platelet activity, and perturb the vascular endothelium. Altogether, these changes will result in a prothrombotic state. In this review, we describe the aetiology of PsO, as well as the pathophysiology of the condition. We also consider its relationship to CVD. Given the systemic inflammatory nature of PsO, we evaluate the potential contribution of prominent inflammatory mediators (implicated in PsO pathogenesis) to establishing a prothrombotic state in psoriatic patients.

Circulating ILC precursors expressing CD62L exhibit a type 2 signature distinctly decreased in psoriatic patients.

Human CD117+CRTH2neg innate lymphoid cells (ILC) comprise multipotent precursors (ILCp), which are able to differentiate into subtypes in response to different signals received in peripheral tissues. NKp46+ ILCp have been reported to associate with ILC3 whereas KLRG1+ILCp with ILC2, although the latter can also generate other ILC subsets, thus, maintaining a substantial plasticity. We here showed that CD62L is expressed by ILCp exclusively within KLRG1+ population and its expression marks a loss of their broad differentiation potential.Analysis of cytokine production and relevant markers demonstrated that CD62L+ILCp mainly differentiate into ILC2 whereas CD62Lneg counterpart can also differentiate into other ILC subsets depending on the signals they receive. Remarkably, in peripheral blood of psoriatic patients, where ILC3 are usually enriched, CD62L+ILC were drastically reduced, whereas CD62LnegILC2 upregulated both RORγt and NKp46, thus, suggesting an ongoing conversion to ILC3. Therefore, CD62L now emerges as a potential marker to identify a skewing toward type 2 among ILCp.

Serum concentration of osteopontin and interleukin 17 in psoriatic patients.

Psoriasis is a chronic, autoinflammatory disease characterized by activation and differentiation of naive T lymphocytes towards T helper CD4+ (including Th1 and Th17) and T cytotoxic CD8+. Osteopontin (OPN), which plays an important role in both physiological processes and inflammatory, neoplastic and autoimmune diseases, is also considered in the context of psoriasis pathogenesis. Current data indicates that OPN is a multifunctional protein involved in the modulation of Th1 and Th17 cellular responses, in stimulating keratinocyte proliferation, and in the regulation of cellular apoptosis. The assessment of OPN and interleukin 17 (IL-17) concentrations in the peripheral blood of psoriatic patients in comparison to healthy volunteers as well as the correlations of OPN and IL-17 with the severity of psoriasis. The study included 107 male psoriatic patients and 41 age-matched healthy men. The serum concentrations of IL-17 and OPN were examined using the enzyme-linked immunosorbent assay (ELISA) method. The skin change severity of psoriasis was assessed using the Psoriasis Area and Severity Index (PASI), Body Surface Area (BSA), Physician Global Assessment (PGA), and Dermatology Life Quality Index (DLQI). Psoriatic patients had significantly higher concentrations of OPN (31.65 ng/mL on average) than the healthy volunteers (11.42 ng/mL on average) (p < 0.001). Interleukin 17 was also higher in psoriatic patients (0.53 pg/mL on average) compared to healthy volunteers (0.09 pg/mL on average) (p < 0.001). There was no significant correlation between OPN and IL-17 concentrations in psoriatic patients and in healthy volunteers. Psoriasis severity correlated positively to IL-17 serum concentration, but not to OPN. Although the study did not show a relationship between OPN and IL-17 concentrations in psoriatic patients, it should be emphasized that serum concentrations were significantly higher in the patients with psoriasis compared to healthy volunteers.

Elevated Gene Expression of Interleukin-32 Isoforms Alpha, Beta, Gamma, and Delta in the Peripheral Blood of Chronic Psoriatic Patients.

Inflammatory-mediated reactions have been implicated as contributors in a number of dermatological disorders, including psoriasis. However, the potential of interleukin (IL)-32 and its isoforms to contribute to the pathogenesis of psoriasis remains unexplored. This study was undertaken to investigate the role of IL-32 and its isoforms IL-32α, IL-32β, IL-32γ, and IL-32δ in the peripheral blood of psoriatic patients. The majority of chronic plaque psoriatic patients showed elevated IL-32 mRNA levels in the peripheral blood mononuclear cells (PBMCs) as compared with the levels of IL-32 mRNA in PBMCs of healthy controls (p = 0.001). To further investigate the role of elevated levels of IL-32 in psoriatic patients, IL-32 isoforms mRNAs were determined. All tested isoforms IL-32α, IL-32β, IL-32γ, and IL-32δ were overexpressed in psoriatic patients PBMCs as compared with healthy controls’ PBMCs (p < 0.05). IL-32α mRNA expression was also significantly higher as compared with all other isoforms of IL-32 in PBMCs of psoriatic patients (p < 0.001). In short, this is the first study that shows the role of IL-32 and its isoforms in the peripheral blood of psoriatic patients. Our novel findings support an association between elevated levels of IL-32 and psoriasis. The data also suggest that a major proinflammatory response of IL-32 may derive from IL-32α isoform in psoriasis.

PKC epsilon involvement in Th17 in vitro differentiation: implications in psoriasis pathogenesis

Psoriasis is a noncontagious, arytematous-squamose dermatitits affecting both sexes and all races. Although its exact etiology is largely unknown, it is now recognized as one of the most common immune-mediated disorders and several studies demonstrate an impairment of regulatory T-cells (Tregs) function and an up-regulation of IL-17 levels produced by T-helper 17 lymphocytes (Th17)(1,2). Protein kinase C epsilon (PKCe) is a serine/threonine kinase which plays a key role in the proliferation and differentiation of epidermal cells. We have previously demonstrated a role for PKCe in the pathogenesis of the autoimmune disease Hashimoto’s thyroiditis (3). PKCe is over-expressed in CD4+ T lymphocytes isolated from PBMC fraction in patients affected by this pathology and its forced down-modulation primed the TGF-mediated in vitro Treg polarization of human T CD4+ cells. Since it has been demonstrated that PKC-signalling is altered in psoriatic keratinocytes (4), we investigated the involvement of PKCe in Th17 in vitro differentiation and its potentially implication in immune response correlated to psoriasis. Using western blot and real time PCR, we have observed that PKCe protein levels and mRNA increase during Th17-lineage in vitro differentiation from naive CD4+ T cells with a similar trend of Th17 markers of differentiation STAT3 and RoRyT. Moreover, PKCe overexpression significantly increases STAT3 and phosphorylated STAT3 levels, suggesting that PKCe boosts Th17 polarization. Thereafter, we sought to investigate PKCe expression in CD4+ lymphocytes obtained from peripheral blood of psoriatic patients and we observed that PKCe expression levels are significantly higher compared with healthy donors. Intriguingly, we observed a closely correlation of PKCe expression with PASI index, suggesting an involvement of the kinase with the severity of the disease. Collectively these data suggest that PKCe might be involved in Th17 differentiation, that it could be a key factor to regulate Th17 pathological expansion and therefore a potential psoriatic pharmacological target.

Impaired function of regulatory T cells in patients with psoriasis is mediated by phosphorylation of STAT3

BackgroundPsoriasis is a T cell-mediated chronic inflammatory skin disease. Regulatory T cells (Tregs) are crucial in suppressing immune response to maintain the immune balance. Wheras Tregs from psoriatic patients showed poorly activity in suppressing activation of responder T cells (Tresp), the mechanisms involved in this process are still unknown. ObjectivesIn this study, we investigated the possible role of STAT3 pathway in the pathogenesis of dysfunctional Tregs in psoriasis. MethodsThe suppressive function and the proliferative activity of Tregs were detected from psoriatic patients and normal healthy controls. Expression of phospho-STAT3 in psoriatic Tregs was evaluated by flow cytometry and immunofluorescence. Furthermore, Tregs were treated with Stattic V (STAT3 inhibitor) in order to investigate the role of STAT3 pathway in the function of Tregs. In addition, IL-6, IL-21 and IL-23 treatments were performed to identify the upstream molecules of STAT3 pathway in Tregs. ResultsTregs from peripheral blood of psoriatic patients showed decreased suppressive function, together with phosphorylation of STAT3. In addition, Tregs isolated from psoriatic patients could produce IFN-γ, TNF-α and IL-17. In the co-culture system of Tregs and Tresp isolated from psoriatic patients, addition of STAT3 inhibitor partially restored the suppressive function of Tregs and restrained the expressions of IFN-γ, TNF-α and IL-17 in psoriatic patients. Moreover, we found that IL-6, IL-21 and IL-23 induced the phosphorylation of STAT3 in Tregs. ConclusionsOur findings suggest that psoriatic Tregs experience a predominant STAT3 phosphorylation by exposure to pro-inflammatory cytokines, leading to their impaired functions in suppressing Tresp activation.

Circulating endothelial cell levels in psoriatic patients and their modification after an anti‐TNF‐alpha (Etanercept) treatment

Endothelial function in psoriatic patients has been mainly evaluated through a high-resolution ultrasound measurement of flow-mediated vasodilation in the brachial artery, which is an operator-dependent and technically demanding technique: this characteristic, together with different patient selection criteria, could account for the conflicting results emerging from different studies. Recently, Circulating Endothelial Cells (CECs) level has been suggested as a novel biomarker of vascular injury. The number of CECs was determined by a semi-automated immunomagnetic system (CellSearch system) in peripheral blood of psoriatic patients (n = 48) and healthy subjects (n = 50). In 15 patients, CEC level was also evaluated after 6 months of treatment with an anti-TNF-alpha agent, Etanercept. The plasma levels of high-sensitivity C-reactive Protein (CRP), E-selectin, VEGF and PAI-1 were measured by ELISA. The psoriasis severity was assessed by PASI score. A statistically significant difference (P = 0.001) was found between CEC level in psoriatic patients (10.6 ± 9.4 cells/mL) vs. the control group (3.9 ± 0.9 cells/mL). This count inversely correlated with sE-selectin levels (r(2) = 0.16; P = 0.03). After 6 months of therapy, patients experienced a significant (P < 0.05) decrease in CEC levels (3.4 ± 1.3 cells/mL) and in PASI score (from 11.7 ± 8.1 to 2.1 ± 4.0). The elevated CECs level that we found in a sample of high selected psoriatic patients could be expression of endothelial damage. Lowering of CECs count after treatment with Etanercept support the hypothesis that an effective systemic therapy of psoriasis may also improve the endothelial function.

Reduced Number of Circulating Endothelial Progenitor Cells (CD133+/KDR+) in Patients with Plaque Psoriasis

Background: Psoriasis is associated with an increased cardiovascular risk. Circulating endothelial progenitor cells (CEPCs) play a significant role in the maintenance of vascular homeostasis. Objective: The aim of this study was to evaluate the number of CEPCs in patients with psoriasis compared to controls and assess possible correlations between the number of these cells and the plasma levels of vascular endothelial growth factor (VEGF), soluble vascular endothelial growth factor receptor-1 (sVEGFR-1) and clinical features of psoriasis. Methods: The number of CEPCs, identified as CD133+/KDR+ cells, was determined with flow cytometry in peripheral blood of psoriatic patients (n = 63) and controls (n = 31). The plasma levels of VEGF and sVEGFR-1 were measured with enzyme-linked immunosorbent assay. Results: The number of CEPCs was significantly reduced in psoriatic patients compared with controls (p = 0.000026) and inversely correlated with disease severity (R = –0.283; p = 0.0248). Conclusion: A reduced number of CEPCs may contribute to endothelial dysfunction in patients with psoriasis.

Up-regulation of Id1 in peripheral blood of psoriatic patients

Although the precise causes of psoriasis are unclear, it is widely accepted that psoriasis is a disorder in which factors in the immune system, enzymes, and other biochemical substances that regulate skin cell division are impaired, leading to rapid proliferation of keratinocytes and incomplete keratinization. Expression of the helix-loop-helix transcription factor Id1 (inhibitor of differentiation/DNA binding), functioning as an inhibitor of differentiation, is known to increase in psoriatic skin. However, the molecular involvement of this particular biomarker in the psoriatic immune system remains to be elucidated. We measured Id1 mRNA expression in peripheral blood mononuclear cells (PBMCs) of psoriatic patients and healthy controls using semi-quantitative reverse transcriptase-PCR. The normalized level of Id1 transcripts in psoriatic patients was about 2-fold higher than that in controls (P < 0.05). When we examined the proliferation rate of PBMCs, the stimulation index obtained from the phytohemagglutinin stimulation assay was not significantly different in psoriatic patients. In patients with psoriasis, there was no correlation between the stimulation index and the psoriasis area severity index. We suggest that Id1 has a role in causing psoriatic immune cell symptoms.

Reduced CD26bright expression of peripheral blood CD8+ T‐cell subsets in psoriatic patients

T cells have been shown to be highly relevant in psoriasis. CD26 is a novel T-cell activation marker involved in various T-cell functions, e.g. (i) co-stimulation, (ii) migration and (iii) T-cell memory response. In particular, CD26bright peripheral blood T cells have been shown to be altered in several autoimmune diseases. To characterize CD26-expression of T-cell subsets in psoriatic patients compared to healthy subjects. Peripheral blood was obtained from 15 untreated patients with severe psoriasis and from nine healthy subjects. The presence of specific CD26-related T-cell subsets was assessed by flow cytometry. The CD26bright expression of CD8+ lymphocytes revealed a statistically significant (P<0.05) decrease in psoriatic patients. The majority of CD4+CD26bright cells are CD45RO+, whereas the minority of CD8+CD26bright cells are CD45RO+ in both groups. The present study demonstrates that the CD8CD26bright T-cell population is markedly decreased in peripheral blood of psoriatic patients. Moreover, CD26 expression did not show a restriction to memory T cells. As CD26 is of relevance for T-cell functions, future investigations should focus on elucidating these functions in psoriasis. It is attractive to speculate that the reduction in the CD8CD26bright subpopulation may represent a biomarker for recompartimentalization of activated T cells and a reduced CD8CD26bright count may correlate with increased responsiveness to T-cell targeted treatments.

Preferential expression of alphaEbeta7 integrin (CD103) on CD8+ T cells in the psoriatic epidermis: regulation by interleukins 4 and 12 and transforming growth factor-beta.

Intraepidermal T lymphocytes are a critical element for sustaining the lesional pathology of psoriasis. Integrin alphaEbeta7 (CD103), a ligand for E-cadherin, may play a role in the localization of pathogenic T cells within the epidermis of psoriatic lesions. However, little information is available regarding alphaEbeta7 expression on intraepidermal T cells in psoriasis. To examine alphaEbeta7 expression on intraepidermal T cells in psoriatic lesions and the regulation of alphaEbeta7 expression on T cells in response to cytokines. T-cell expression of alphaEbeta7 was examined by immunohistochemistry and flow cytometry. In vitro regulation of alphaEbeta7 expression on CD4+ or CD8+ T cells purified from peripheral blood of healthy donors was also examined. Immunohistochemical staining revealed expression of alphaEbeta7 on a greater proportion of epidermal T cells than dermal T cells. Nearly 30% of intraepidermal CD4+ T cells were found to express alphaEbeta7 on flow cytometry, whereas more than 80% of intraepidermal CD8+ T cells expressed this integrin. In contrast, few T cells expressed alphaEbeta7 in the peripheral blood of psoriatic patients. The in vitro culture experiment confirmed that alphaEbeta7 was preferentially expressed on CD8+ T cells after stimulation with anti-CD3 monoclonal antibodies. Addition of transforming growth factor-beta and interleukin-4 upregulated alphaEbeta7 expression on T cells, whereas interleukin 12 downregulated this. Furthermore, alphaEbeta7 expression on established memory CD8+ T cells was not so reversible as that on CD4+ T cells. Preferential and stable expression of alphaEbeta7 on CD8+ T cells may be involved in the lesional pathology of psoriasis.

Lipid analysis of peripheral blood monocytes in psoriatic patients using Fourier-transform infrared microspectroscopy.

In psoriasis vulgaris, there are immunological abnormalities of T cells and monocytes. We previously demonstrated that monocytes in the peripheral blood of patients with psoriasis vulgaris are activated and produce an excess of inflammatory cytokines. It has long been suggested that fat metabolism is impaired in patients with this illness. In addition, it has been reported that macrophages activated by engulfing low density lipoprotein (LDL) immune complexes release large quantities of tumor necrosis factor (TNF)-alpha and interleukin (IL)-1beta. Hence we hypothesized that the monocytes of psoriatic patients are activated by engulfing lipids and overproduce inflammatory cytokines. Therefore we measured both the serum and monocyte levels of lipids in the peripheral blood of psoriatic patients. At the same time, we calculated the psoriasis area and severity index (PASI) scores and analyzed their correlation with the lipid kinetics. The results showed that the serum cholesterol ester level and the cholesterol ester level in monocytes of psoriatic patients were significantly higher than those in healthy individuals. However, the cholesterol ester level in monocytes of patients with hyperlipidemia was also high, and there was no correlation between cholesterol ester level in monocytes of psoriatics and PASI scores. The cholesterol ester level in the monocytes of psoriatic patients was high, but this does not seem to play an important role in the pathogenesis of psoriasis.

Monocyte Function in Psoriasis

Monocytes derived from the peripheral blood of psoriatic patients demonstrated a significantly higher phagocytic capacity (36 to 40%) for both 125I-labeled Shigella flexneri and 125I-labeled Staphylococcus albus compared with monocytes from healthy subjects. Monocytes from psoriatic patients showed a 2-to-4fold increase in bactericidal capacity against S. albus when compared with normal monocytes. However, the bactericidal capacity of monocytes from diphylline-treated patients did not differ from that of the control subjects. The antibody-dependent cellular cytotoxicity (ADCC) activity against EL4 tumor cells was found to be similar in both psoriatic patients and control subjects. It is postulated that these abnormalities of monocyte function in psoriasis are caused by a decreased cAMP/cGMP ratio similar to the decreased cAMP/cGMP ratio found in the lesional epidermis of this disease. It seems therefore, that the psoriatic abnormality is not confined to only one type of cell, the epidermal cell.

Enhanced Chemotactic and Phagocytic Activities of Leukocytes in Psoriasis Vulgaris

Leukocytes derived from the peripheral blood of psoriatic patients demonstrated an enhanced chemotactic response compared with leukocytes from healthy subjects. No significant difference was detected between the chemotactic response of leukocytes from patients with minimal or no skin involvement and those from patients with extensive lesions. Psoriatic leukocytes also had a significantly higher capacity to engulf 125I labeled Shigella flexneri than control leukocytes. It is postulated that a decrease in the cyclic AMP/cyclic GMP ratio in psoriatic leukocytes, similar to the imbalance of these 2 cyclic nucleotides found in the lesional epidermis of psoriasis, might be the cause of their enhanced chemotactic and phagocytic activities.