Importance of regulatory T cells in the pathogenesis of psoriasis: review of the literature.

Psoriasis is a common chronic relapsing inflammatory cutaneous disease; the main role in the inflammation of this condition is played by lymphocyte Th1, Th17 and their cytokines. The activity of these cells is modulated by a particular kind of T cells recently described: the T regulatory cells (Treg). These are able to inhibit the immunological response and to maintain the cutaneous immunological homeostasis, thus preventing autoimmunity against self antigens. Few data are available in the literature as to Treg in psoriasis; several studies demonstrate that the function of these cells is impaired in this condition and treatments for psoriasis may increase the number and activity of Treg. The role of these cells in the pathogenesis of psoriasis is very important to understand how they may contribute to the development of this cutaneous disorder. In the near future it would be possible to target therapies at these defects, improving the activity of these cells and maintaining cutaneous homeostasis, preventing psoriasis or other inflammatory cutaneous conditions.

CD4+ CD25+ T-regulatory cells in psoriasis. Correlation between their numbers and biologics-induced clinical improvement.

BACKGROUND: Regulatory T-cells (T-reg) play a central role in the immunopathogenesis of psoriasis. T-reg cells are both functionally and numerically impaired in psoriasis and they are up-regulated by drug therapy. OBJECTIVE: To analyse the circulating CD4+CD25 bright FOXP3+ subset in 14 patients with vulgaris/arthropathic psoriasis treated with biological drugs and to investigate their relationship with the clinical response. METHODS: The CD4+ CD25 bright FOXP3+ expression was determined in peripheral blood by flow cytometry at baseline and during treatment. RESULTS: A response was obtained in 10/14 patients with increased CD4+ CD25 bright FOXP3+ (T-reg) in peripheral blood after the first month and then 4 months after therapy with biological drugs. This increase is associated with the achievement of a clinical response and with a reduction in the Psoriasis Activity and Severity Index (PASI) score. 2/14 patients showed a decrease in T-reg after drug therapy and this decrease correlated with a worsening of the clinical skin. CONCLUSION: Biological drugs induce circulating T-reg up-regulation in psoriatic patients; such an increase is an early predictive marker of clinical response.

Correlation between plasmatic levels of vitamin D and PASI score.

BACKGROUND: Psoriasis is a common, inflammatory, chronic, relapsing skin disease. The pathogenesis is multifactorial and it is involved both innate and acquired immunity. Several studies have shown the important role of vitamin D in the pathogenesis of this disorder. In this study we have evaluated a possible correlation between vitamin D and clinical severity of psoriasis calculated using the Psoriasis Area Severity Score (PASI) score. METHODS: In this case control study we included 141 Caucasian subjects affected by moderate to severe psoriasis and 62 healthy controls. We have calculated PASI score and serum levels of vitamin D. RESULTS: Psoriatic patients had significantly lower serum levels of 25(OH)D than healthy controls. Using no parametric Spearman's coefficient test between serum levels of vitamin D and the PASI score we found a statistical significant correlation. However, the statistical significance was not reached analyzing separately the patients with psoriatic arthritis, while it was confirmed for patients without an articular involvement. CONCLUSIONS: The present study confirm that serum levels of vitamin D are significantly lower in psoriatic patients and correlate with the clinical severity of psoriasis; these data suggest that psoriatic patients could be screened for vitamin D insufficiency for a more comprehensive management.

Safety and efficacy of anti-tumor necrosis factors α in patients with psoriasis and chronic hepatitis C.

Up to date, in literature, it is still debated the role of anti-tumor necrosis factors (TNF)-α treatments in hepatitis C virus (HCV) patients. TNF-α performs a lot of functions, it is an important pro-inflammatory cytokine and it is involved in the host's immunity. Since TNF-α is implicated in the apoptotic signaling pathway of hepatocytes infected by HCV, anti TNF-α therapy may increase the risk of viral replication or their reactivation. However the treatment of anti TNF-α could have a healthful role because TNF-α appears to be engaged in the pathogenesis of liver fibrosis, inducing apoptotic pathways. We describe the case of a patient with plaque-type psoriasis and concomitant chronic HCV, who was treated successfully with anti-TNF agents simultaneously to cyclosporine without sign of reactivation of HCV and increase of liver enzymes. Our personal experience shows that anti-TNF-α agents are not only effective but also safe. Furthermore the combination therapy of cyclosporine and anti-TNF-α appears to be well-tolerated and able to reduce the amount of liver enzymes as well as HCV-viral-load. However systematic, large-scale studies with long follow-ups will be needed to confirm our results, in association with close liver function monitoring.

Psoriasis and bone mineral density: implications for long-term patients.

Psoriasis is a chronic inflammatory disease associated with several comorbidities. Osteoporosis is defined as a reduction in bone mineral density with impaired bone microarchitecture. Several mechanisms may be implicated as a possible cause for the association between psoriasis and osteoporosis, such as systemic inflammation, anti-psoriatic drug intake and joint dysfunction for psoriatic arthritis (PsA). The aim of the present study was to assess bone mineral density (BMD) in patients with psoriasis, correlating the prevalence of osteopenia/osteoporosis with Psoriasis Area and Severity Index (PASI) score, mean duration of psoriatic disease, PsA and previous treatments for psoriasis. Forty-three consecutive patients with psoriasis, 19 of whom were affected by the arthropathic form, were enrolled. We evaluated the severity of psoriasis as measured by PASI score, the CASPAR criteria and ultrasounds of the joints to verify the diagnosis of PsA and the age of psoriasis onset to estimate mean disease duration. Patients underwent a bone density scan of the lumbar spine and femoral neck by dual-energy X-ray absorptiometry to measure BMD. Patients with osteopenia/osteoporosis showed a statistically significant longer average duration of psoriatic disease (17 years), compared to patients affected by psoriasis with normal T-score (8.8 years) (P = 0.04). The linear logistic regression confirms a significant relation between mean psoriatic disease duration and BMD alterations (P = 0.04). Our results suggest the necessity of an early diagnostic evaluation of bone metabolism in patients with psoriasis, especially if characterized by longer disease duration.

Serum levels of functional T-regs in vitiligo: our experience and mini-review of the literature.

Vitiligo is an acquired depigmentary skin disorder due to the loss of cutaneous melanocytes or alteration in melanocyte function, affecting over 0.5% of the world population. The exact cause of melanocyte loss in non-segmental vitiligo is still debatable, but many observations have pointed to the main role of cellular immunity. Earlier evidence has shown that depigmenting vitiligo skin is accompanied by CD8+ T cytotoxic lymphocytes infiltrates at the dermal-epidermal junction. Dysregulation of Tregs may be one of the factors that can break tolerance to melanocyte self-antigens and contribute to the pathogenesis of vitiligo. The objectives of the present study were to provide evidence of the presence of a functional defect and decrease of peripheral regulatory T cells in patients affected by vitiligo, supporting the hypothesis of their involvement in the pathogenesis of the disease, opening new possibilities to advance therapeutic approaches.

Gemcitabine-induced extensive skin necrosis.

An 82-year-old woman presented with oedema and extensive necrotic ulcerative lesions on the back side of her lower limbs, emerging after the second cycle of chemotherapy consisting of Gemcitabine for metastatic pancreatic cancer. The absence of any convincing argument in favor of cardiovascular or autoimmune disease led us to attribute the onset of skin necrosis to chemotherapy administration. Although skin ischemia has also been described as a paraneoplastic syndrome, in this case we could observe a temporal and causal relationship to Gemcitabine infusion. Recently, this drug has been associated with important vascular side effects; its vascular toxicity is in fact higher than previously estimated. To our knowledge, careful attention should be reserved to neoplastic patients candidated to Gemcitabine administration, especially if previously affected by arterial vascular disease, venous thromboembolism, or collagenoses.