Lee JY, et al. Ann Dermatol. 2017 Dec;29(6):761-767. https://doi.org/10.5021/ad.2017.29.6.761

Background Psoriasis is a chronic, immune‐mediated disease, characterized by symptoms that include itching and skin pain and is often associated with comorbidities. Patients have a substantial detriment to quality of life (QoL) and work productivity with associated cost burden. Objectives To investigate the incremental burden of comorbidities, itch and affected body areas among systemic eligible patients with psoriasis, using a multinational survey of dermatologists and their patients with psoriasis. Methods Multinational data from the Growth from Knowledge (GfK) Disease Atlas Global Real‐World Evidence program were used. Eligible patients were identified as those who were currently having or had ever had moderate‐to‐severe psoriasis, and must have been receiving prescription treatments at the time of the survey. Multivariable regression analyses were conducted to assess the incremental burden among psoriasis patients with physical and psychological comorbidities, itch and affected visible and sensitive body areas vs. psoriasis patients without these conditions, respectively. Results The study enrolled 3821 patients with psoriasis, from nine countries, with an average Psoriasis Area and Severity Index score of 6·4. The presence of comorbidities was associated with a significant increase in the likelihood of skin pain, lower QoL, greater work impairment and increased usage of medical resources (except in psoriasis patients with obesity and type 2 diabetes). Psoriasis patients suffering from itch and those with visible and sensitive affected body areas also had impaired QoL vs. those without these conditions. Conclusions Psoriasis patients with physical and psychological comorbidities, itch and affected visible and sensitive body areas had lower QoL and greater work impairment compared to those without these conditions.

Vitiligo is an autoimmune skin disease characterized by the destruction of melanocytes by autoreactive CD8 ⁺ T cells. Melanocyte destruction in active vitiligo is mediated by CD8 ⁺ T cells, but the persistence of white patches in stable disease is poorly understood. The interaction between immune cells, melanocytes, and keratinocytes in situ in human skin has been difficult to study due to the lack of proper tools. We combine noninvasive multiphoton microscopy (MPM) imaging and single-cell RNA-Seq (scRNA-Seq) to identify subpopulations of keratinocytes in stable vitiligo patients. We show that, compared with nonlesional skin, some keratinocyte subpopulations are enriched in lesional vitiligo skin and shift their energy utilization toward oxidative phosphorylation. Systematic investigation of cell-to-cell communication networks show that this small population of keratinocyte secrete CXCL9 and CXCL10 to potentially drive vitiligo persistence. Pseudotemporal dynamics analyses predict an alternative differentiation trajectory that generates this new population of keratinocytes in vitiligo skin. Further MPM imaging of patients undergoing punch grafting treatment showed that keratinocytes favoring oxidative phosphorylation persist in nonresponders but normalize in responders. In summary, we couple advanced imaging with transcriptomics and bioinformatics to discover cell-to-cell communication networks and keratinocyte cell states that can perpetuate inflammation and prevent repigmentation.