Immune cell activity during anti-TNF treatment in patients with psoriasis and psoriatic arthritis.

Psoriasis is a chronic, inflammatory skin disease characterized by a dysregulated immune response and systemic inflammation. Up to one-third of patients with psoriasis have psoriatic arthritis (PsA). Targeted treatment with antibodies neutralizing tumor necrosis factor (TNF) can ameliorate both diseases. We here explored the impact of long-term infliximab treatment on the composition and activity status of circulating immune cells involved in chronic skin and joint inflammation. Immune cells were analyzed by multicolor flow cytometry. We measured markers of immune activation in peripheral blood mononuclear cell (PBMC) populations in 24 infliximab-treated patients with psoriasis/psoriatic arthritis compared to 32 healthy controls. We observed a significant decrease in the frequency of both peripheral natural killer (NK) cells and their subset CD56dimCD16+ NK cells in PsA compared to healthy controls and patients with psoriasis. The latter had a strong positive correlation with PASI in these patients, while CD56brightCD16- NK cells were negatively correlated with PASI. In addition, we observed an upregulation of CD69+ intermediate CD14+CD16+ and CD69+ classical CD14+CD16- monocytes in PsA and increased activity of CD38+ intermediate CD14+CD16+ monocytes in patients with psoriasis. Compared to healthy controls, psoriasis patients demonstrated shifts of the three B cell subsets with a decrease in transitional CD27-CD38high B cells. Our exploratory study indicates a preserved pathophysiological process including continuous systemic inflammation despite clinical stability of the patients treated with infliximab.

Serum cytokine measurements and biological therapy of psoriasis - Prospects for personalized treatment?

Psoriasis is an immune-mediated disease where the IL-23/Th17 axis as well as TNF comprise main targets of biological therapy. Immune profiling has so far not been embraced as a clinical tool. We aimed to investigate relationships between individual serum cytokine levels in 40 psoriasis patients before and after receiving biological therapy and Psoriasis Area and Severity Index (PASI) and Dermatological Life Quality Index (DLQI). Serum concentration of 25 cytokines was determined by Luminex technology. Mean PASI and DLQI decreased by 71% and 65%, respectively. Increase of IL-2 positively correlated with improvement of PASI and DLQI. Moreover, increase of IL-5, IL-10, IL-12, IL-22 and GM-CSF correlated with treatment effect. Notably, logistic regression revealed four times higher risk of having severe psoriasis when IL-17A increased by 1 pg/mL (OR: 4.06, P < 0.05). Selected serum cytokines might constitute useful biomarkers for monitoring disease activity and optimizing therapeutic strategies in psoriasis patients.

CD11c(+) dendritic cells rather than Langerhans cells are reduced in normal skin of immunosuppressed renal transplant recipients.

The increased risk of squamous cell carcinomas (SCC) in renal transplant recipients (RTR) is related to impaired immunosurveillance as a consequence of immunosuppressive therapy. Since dendritic cells (DC) play an important role in immunosurveillance, we investigated the quantity of DC subsets and macrophages in normal skin of RTR and immunocompetent controls by immunohistochemistry. In this comparative study Langerhans' cells (LC) were present in similar numbers in RTR and controls. The number of CD11c+ DC was significantly reduced in RTR, particularly in patients on triple treatment therapy, compared with controls. Macrophages were significantly increased. Plasmacytoid DC were not detected in normal skin. The reduced quantity of CD11c+ DC and increased number of macrophages in normal skin of immunosuppressed RTR may contribute to the increased incidence of SCC in RTR. This finding underlines the role of DC subsets in immunosurveillance, and may have implications for our understanding of the effect of immunosuppression on DC subsets.