T helper type 1-related molecules as well as interleukin-15 are hyperexpressed in the skin lesions of patients with pyoderma gangrenosum.

Pyoderma gangrenosum (PG) is a rare, immune-mediated skin disease classified into the group of neutrophilic dermatoses. Although a number of studies confirmed the central role of innate immunity, only few studies have investigated the possible contributing role of acquired immunity. In particular, no reports concerning T helper type 1 (Th1) and Th2 cells are available as yet. Therefore, 15 patients with PG, five with Sweet's syndrome (SS) and nine skin specimens from healthy controls (HC) were investigated, evaluating the expression of Th1-related markers interleukin (IL)-12, interferon (IFN)-γ, C-X-C motif chemokine receptor 3 (CXCR3) and C-C motif chemokine receptor 5 (CCR5), of the Th2-related molecules IL-4, IL-5, IL-13 and CCR3, of the co-stimulatory axis CD40/CD40 ligand, of IL-15 and the natural killer (NK) cell marker CD56 in skin lesions by immunohistochemistry. Patients with PG and SS showed a higher expression of Th1 markers than HC. Conversely, IL-5- and CCR3-expressing cells were less numerous in PG skin lesions compared to SS (P = 0·0157 and < 0·0001, respectively). Both CD40 and CD40L were expressed more in PG than in SS and HC (P < 0·0001 for both). Finally, the number of IL-15+ and CD56+ cells was higher in the skin of patients with PG than in those of SS and HC (P < 0·0001 for both). Our results suggest that Th2 cells are down-regulated in PG. At the same time, over-expression of the co-stimulatory axis CD40/CD40L amplifies the impairment of the Th1/Th2 balance. Both these findings might explain the most aggressive behaviour of PG in comparison to SS. Moreover, over-expression of IL-15+ and CD56+ cells may suggest a possible role of NK cells in the pathogenesis of the disease.

Drug-induced cutaneous vasculitides.

Cutaneous vasculitides (CV) can be idiopathic or secondary to several triggers, including drugs, which account for up to 30% of all the cases of CV. Several drugs can induce CV, including some medications commonly used in dermatology, including minocycline, and several new drugs, such as anti-TNF agents. Different pathomecanisms are involved in the development of drug-induced CV, including the formation and deposition of immune complexes, the induction of neutrophil apoptosis, the formation of neoantigens between the drugs and proteins from the host, the shift of the immune response, and others. Although the diagnosis is difficult, because the clinical picture of drug-induced CV is in general indistinguishable from that of other forms of CV, it is important to recognize such entities in order to correctly manage the patient. Anamnesis, diagnostic algorithms to assess the likelihood of the association between a drug and a cutaneous reaction, skin biopsy and laboratory testing (including the search for antineutrophil cytoplasmic antibodies) are useful tools to make a diagnosis of drug-induced CV. About the therapy, while in idiopathic vasculitides the treatment is usually more aggressive and long-lasting, very often requiring a maintenance therapy with immunosuppressive drugs, in drug-induced CV the discontinuation of the suspected drug alone is usually enough to achieve complete remission, making the prognosis usually very good.

Drug induction in connective tissue diseases.

Connective tissue diseases (CTDs) are defined as a group of acquired disorders resulting from persistent immuno-mediated inflammation. Several classes of drugs seem to be capable of inducing or exacerbating CTDs. A drug-induced (DI) syndrome is defined as a condition temporally related to continuous drug exposure, which resolves upon drug discontinuation. Among CTDs, lupus erythematosus is the most widely known and investigated DI syndrome. However, in recent years, the association between the onset of other CTDs, such as dermatomyositis (DM) and morphea/systemic sclerosis (SSc) has increased in patients with preceding exposure to particular substances. Herein, we conducted a review of published case reports including DM and morphea/SSc, evaluating the real causality among drugs and these syndromes.

Regulatory T cells in skin lesions and blood of patients with bullous pemphigoid.

BACKGROUND: Although regulatory T cells (Tregs) are affected in several autoimmune skin diseases, only two studies have been performed in patients with bullous pemphigoid (BP) with contrasting results. OBJECTIVE: To characterize Tregs and to determine the serum levels of regulatory cytokines in patients with BP. METHODS: In BP lesional skin, immunohistochemistry and confocal microscopy were performed for CD4(+) , CD25(+) , forkhead/winged helix transcription factor (FOXP3)(+) , transforming growth factor (TGF)-ß(+) and interleukin (IL)-10(+) cells. In addition, the number of CD4(+) CD25(++) FOXP3(+) Tregs in peripheral blood was assessed by flow cytometry, and the levels of TGF-ß and IL-10 were determined in serum samples by enzyme-linked immunosorbent assay before and after steroid therapy. Controls included patients with psoriasis, atopic dermatitis (AD) and healthy donors. RESULTS: The frequency of FOXP3(+) cells was significantly reduced in skin lesions from patients with BP (P < 0.001) compared with psoriasis and AD. Moreover, the number of IL-10(+) cells was lower in BP than in psoriasis (P < 0.001) and AD (P = 0.002), while no differences were observed in the number of TGF-ß(+) cells. CD4(+) CD25(++) FOXP3(+) Treg in the peripheral blood of patients with BP was significantly reduced compared with healthy controls (P < 0.001), and augmented significantly after steroid therapy (P = 0.001). Finally, TGF-ß and IL-10 serum levels were similar in patients with BP compared with healthy controls. However, after therapy, BP patients showed significantly higher IL-10 serum levels than before therapy (P = 0.01). CONCLUSIONS: These data suggest that the depletion of Tregs and of IL-10 in patients with BP may be an important factor in the pathogenesis of the disease.

Effects of tacrolimus ointment on Toll-like receptors in atopic dermatitis.

BACKGROUND: Alterations of Toll-like receptors (TLRs) seem to play a role in susceptibility to atopic dermatitis (AD). AIM: To investigate the expression of TLRs in moderate to severe chronic AD in adults before and after a 3-week treatment with 0.1% tacrolimus ointment, compared with 0.1% topical hydrocortisone-17-butyrate. METHODS: In total, 21 adult patients with AD were enrolled: 11 were given tacrolimus ointment and 10 were given hydrocortisone butyrate; a further 6 healthy adults formed the control group. The clinical efficacy of the treatment was assessed using the SCORing Atopic Dermatis (SCORAD) index. Biopsies were taken from lesional skin before and after treatment, which were stained immunohistochemically with monoclonal antibodies to TLR-1, -2, -4 and -9. RESULTS: Both 3-week topical treatments improved signs and symptoms in all 21 patients considered, with no significant difference between the two groups. In the skin of patients with AD, TLR-1 was overexpressed and TLR-2 underexpressed compared with healthy controls, whereas no differences were found for TLR-4 and TLR-9. Staining for TLR-1 was decreased in both groups after treatment. AD specimens had higher levels of TLR-2 expression after either treatment compared with baseline, and levels were higher after tacrolimus treatment than after hydrocortisone butyrate. Neither tacrolimus nor hydrocortisone butyrate affected expression of TLR-4 or TLR-9. CONCLUSION: Short-term therapy with tacrolimus ointment reduced expression of TLR-1, which may inhibit the antimicrobial potential of TLR-2, and also reversed the impairment of TLR-2 in AD lesions. Expression of TLR-4 and TLR-9 was not affected by tacrolimus.

The role of etanercept on the expression of markers of T helper 17 cells and their precursors in skin lesions of patients with psoriasis vulgaris.

Very recently, it has been demonstrated that CD161, retinoic acid-related orphan receptor gamma-t (RORgamma-t) and CC-chemokin receptor 6 (CCR6) can be considered good surface markers to detect T helper 17 cells and their precursors, T cell populations that are considered to play an important role in the pathogenesis of psoriasis. In the present study, we evaluate the clinical involvement by calculating the PASI score and the number of CD4+, CD161+, RORgammat+ and CCR6+ cells before and after a 12-week course with etanercept or acitretin in patients with moderate-to-severe, plaque-type psoriasis vulgaris. Ten patients were given etanercept 50 mg twice weekly and 10 patients acitretin 0.4 mg/kg per day, both for 12 weeks. At the baseline and at the end of the treatment PASI was calculated, and skin biopsies were taken to evaluate the expression of CD4, CD161, RORgammat and CCR6 by immunohistochemistry. As controls, 10 patients with atopic dermatitis (AD) were included in the study. After 12 weeks, PASI was significantly lower than at the baseline for both groups. However, etanercept-treated patients showed lower PASI than acitretin-treated ones. While CD4+ cell numbers were similar in both diseases, all the other markers, that are considered more specific for Th17 cells and their precursors, were more expressed in psoriasis than in AD. Furthermore, only etanercept, but not acitretin, was able to significantly reduce CD161+, RORgammat+ and CCR6+ cells in skin lesions of patients with psoriasis. Our study provides further evidence of the role of Th17 pathway in the pathogenesis of psoriasis. Furthermore, our findings suggest that etanercept is able to downregulate the expression of the recently recognized markers of Th17 cells and their precursors CD161, RORgammat and CCR6, while acitretin is not. This activity on the Th17 lineage may contribute to the efficacy of etanercept in the treatment of psoriasis.

Characterization of regulatory T cells in patients with dermatomyositis.

The purpose of this study was to characterize regulatory T cells (T(reg)) in skin lesions and peripheral blood from patients with dermatomyositis (DM) and to determine the serum levels of regulatory cytokines in the disease. In skin biopsy specimens from patients with DM, immunohistochemistry was performed for CD4(+), CD25(+), forkhead/winged helix transcription factor (FoxP3)(+), transforming growth factor (TGF)-ß(+) and interleukin (IL)-10(+) cells. Additionally, we defined the number of T(reg) subpopulations in peripheral blood by flow cytometry using monoclonal antibodies against CD4, CD25, FoxP3, CD45RO, CD95, CCR4 and CLA. The levels of TGF-ß and IL-10 were also determined in serum samples from patients with DM by enzyme-linked immunosorbent assays. Controls included patients with cutaneous lupus erythematosus, psoriasis and atopic dermatitis (AD) as well as healthy donors. The frequency of FoxP3(+) cells was significantly reduced in skin lesions from patients with DM (p < 0.001) compared to psoriasis and AD. Moreover, the number of cells positive for TGF-ß was lower in DM than in psoriasis and AD, while IL-10(+) cells were significantly reduced only compared to psoriasis. The number of CD4(+)CD25(++)FoxP3(+) T(reg) in the peripheral blood of patients with DM was significantly reduced compared to healthy controls (p < 0.05), whereas other cell populations showed no significant differences. Finally, TGF-ß and IL-10 serum levels were significantly lower in patients with DM compared to healthy controls (p < 0.05). These data suggest that the depletion of T(reg) and their main effector cytokines in the skin and the serum of patients with DM may be an important factor in the pathogenesis of the disease.

Regulatory T cells in the skin lesions and blood of patients with systemic sclerosis and morphoea.

BACKGROUND: Systemic sclerosis (SSc) and morphoea are connective tissue diseases characterized by fibrosis of the skin. Although to date their pathogenesis has not been clearly defined, it is thought that autoimmunity may play a role in the development of the skin lesions observed in both these diseases. As regulatory T cells (Tregs) play a key role in the modulation of immune responses, it has recently been suggested that Treg impairment may lead to the development of autoimmune diseases. OBJECTIVES: To investigate the presence of Tregs and their immunomodulatory cytokines, transforming growth factor (TGF)-beta and interleukin (IL)-10, in patients with SSc and morphoea. PATIENTS/METHODS: Fifteen patients with SSc and 15 with morphoea were enrolled. Immunohistochemistry was applied to identify FoxP3+ (forkhead/winged helix transcription factor) Tregs, TGF-beta+ cells and IL-10+ cells in the skin, cytofluorometry to detect CD4+CD25+FoxP3+ Tregs in the blood, and enzyme-linked immunosorbent assays to analyse TGF-beta and IL-10 serum levels. RESULTS: Fewer FoxP3+ Tregs and TGF-beta+ and IL-10+ cells were found in the skin of patients with scleroderma than in controls. Similarly, there were reduced TGF-beta and IL-10 serum levels and fewer circulating CD4+CD25brightFoxP3+ cells in patients with SSc or morphoea, than in controls. CONCLUSIONS: The quantitative reduction of Tregs, together with that of TGF-beta and IL-10 serum levels, may be responsible for the loss of tolerance observed in both SSc and morphoea.

Serum levels of IL-17 and IL-22 are reduced by etanercept, but not by acitretin, in patients with psoriasis: a randomized-controlled trial.

INTRODUCTION: There are no controlled trials comparing etanercept and acitretin efficacy and therapeutic mechanisms in psoriasis. MATERIALS AND METHODS: In the present study, 30 patients were given etanercept 50 mg twice weekly and 30 patients acitretin 0.4 mg/kg per day, both for 12 weeks. Before and after treatment, psoriasis area and severity index was calculated, and serum levels of interleukin (IL)-17, IL-22, and IL-23 were investigated. RESULTS: After treatment, psoriasis area and severity index was significantly lower for both groups. However, etanercept-treated patients showed lower psoriasis area and severity index than acitretin-treated ones. Psoriasis patients showed higher IL-17 and IL-22 levels than controls, while no IL-23 was found in any serum. Furthermore, a correlation between IL-17 levels and psoriasis severity was found. Only etanercept was able to reduce IL-17 and IL-22 levels. CONCLUSIONS: Our findings suggest that etanercept is more effective than acitretin in the treatment of psoriasis and that it is able to affect Th17 system.

The comparative effects of tacrolimus and hydrocortisone in adult atopic dermatitis: an immunohistochemical study.

BACKGROUND: While many studies have demonstrated the efficacy and safety of tacrolimus ointment in the treatment of atopic dermatitis (AD), only a few have investigated the effects of tacrolimus on inflammatory cells and their cytokine gene expression in patients with AD. OBJECTIVES: To characterize further the immunophenotype of infiltrating cells and the production of certain cytokines before and after treatment with topical tacrolimus and hydrocortisone butyrate. METHODS: Nine adult patients with moderate to severe AD were treated with tacrolimus ointment, while seven control patients were treated with hydrocortisone butyrate ointment. We performed lesional skin biopsies before and after treatment. These were stained immunohistochemically with a panel of monoclonal antibodies including those to CD1a, CD3, CD4, CD8, myeloperoxidase, EG1, EG2, tryptase, interferon-gamma, interleukin (IL)-4, IL-5, IL-12, IL-13, receptors for CXC chemokines (CXCR) 3 and 4, and receptor 3 for CC chemokines. RESULTS: CD3+, CD4+ and CD8+ lymphocytes, and eosinophil and neutrophil granulocytes were significantly reduced in post-treatment tacrolimus specimens, while CD1a+ cells and mast cells were not. The expression of cytokines and chemokine receptors tested, except for CXCR3, was diminished by tacrolimus treatment. Moreover, tacrolimus produced a greater reduction of lymphocytes, eosinophils and most cytokines than that induced by hydrocortisone butyrate. CONCLUSIONS: Tacrolimus not only inhibits T-lymphocyte proliferation and cytokine production, but also plays an important role in the IL-12-induced shift from a T-helper (Th) 2 to a Th1 cytokine profile that characterizes the development of chronic AD. Tacrolimus also demonstrates wider pharmacodynamic effects than hydrocortisone.

Cellular adhesion molecules in chronic urticaria: modulation of serum levels occurs during levocetirizine treatment.

BACKGROUND: Some antihistamines are capable of reducing levels of adhesion molecules in wealing tissues of patients with chronic urticaria (CU). OBJECTIVES: To determine if 6 weeks of therapy with levocetirizine 5 mg once daily would also induce any decrease in serum levels of intercellular adhesion molecule-1, vascular cell adhesion molecule-1, endothelial leucocyte adhesion molecule-1 (ELAM-1) or P-selectin in subjects with CU and chronic autoimmune urticaria. METHODS: Thirty-six patients with CU (18 with positive and 18 with negative autologous serum skin test) were studied, together with 10 control healthy subjects. All patients received levocetirizine 5 mg daily. Serum soluble cellular adhesion molecule (CAM) levels were determined by immunoenzymatic assay before and after the end of the study period. Disease activity was recorded according to the EAACI/GA(2)LEN/EDF scoring system. RESULTS: After levocetirizine therapy CAM levels decreased in patients with CU, significantly in the cases of ELAM-1 and P-selectin. Patients' clinical scores improved during regular antihistamine therapy. CONCLUSIONS: Levocetirizine 5 mg daily demonstrated a broad anti-inflammatory effect in patients with CU. The significant decrease in serum levels of ELAM-1 and P-selectin might reflect the inhibitory activity on neutrophil rolling and extravasation towards inflamed skin.