Iodine is oxidized and reduced as part of a biogeochemical cycle that is especially pronounced in the oceans, where the element naturally concentrates. The use of oxidized iodine in the form of iodate (IO₃^-) as an electron acceptor by microorganisms is poorly understood. Here, we outline genetic, physiological, and ecological models for dissimilatory IO₃^- reduction to iodide (I^-) by a novel estuarine bacterium, Denitromonas sp. IR-12. Our results show that dissimilatory iodate reduction (DIR) by strain IR-12 is molybdenum-dependent and requires an IO₃^- reductase (idrA) and likely other genes in a mobile cluster with a conserved association across known and predicted DIR microorganisms (DIRM). Based on genetic and physiological data, we propose a model where three molecules of IO₃^- are likely reduced to three molecules of hypoiodous acid (HIO), which rapidly disproportionate into one molecule of IO₃^- and two molecules of iodide (I^-), in a respiratory pathway that provides an energy yield equivalent to that of nitrate or perchlorate respiration. Consistent with the ecological niche expected of such a metabolism, idrA is enriched in the metagenome sequence databases of marine sites with a specific biogeochemical signature (high concentrations of nitrate and phosphate) and diminished oxygen. Taken together, these data suggest that DIRM help explain the disequilibrium of the IO₃^-:I^- concentration ratio above oxygen-minimum zones and support a widespread iodine redox cycle mediated by microbiology.

Metabolomics is an emerging new "omics" field involving the systematic analysis of the metabolites in a biologic system. These metabolites provide a molecular snapshot of cellular activity and are thus important for understanding the functional changes in metabolic pathways that drive disease. Recently, metabolomics has been used to study the local and systemic metabolic changes in psoriasis and its cardiometabolic comorbidities. Such studies have revealed novel insights into disease pathogenesis and suggest new biochemical signatures that may be used as a marker of psoriatic disease. This review will discuss common strategies in metabolomics analysis, current findings in the metabolomics of psoriasis, and emerging trends in psoriatic metabolomics.

Introduction

Interleukin (IL)-17 inhibitors are the most recent class of monoclonal antibodies approved by the FDA for psoriasis treatment. Preclinical and phase II studies of brodalumab, a high-affinity IL-17 receptor monoclonal antibody, have been encouraging.

Methods

We conducted a literature search using the PubMed database in order to assess the efficacy and safety profile of brodalumab. The search included the following key words: "psoriasis" and "IL-17" or "brodalumab." We also reviewed citations within articles to identify relevant sources.

Results

At week 12, the proportion of patients attaining a 75% improvement from the baseline Psoriasis Area and Severity Index (PASI 75) was similar among the three phase III trials (AMAGINE-1, 83%; AMAGINE-2, 86%; AMAGINE-3, 85%). Brodalumab remained efficacious through 52 weeks of treatment. It maintained a satisfactory safety profile; the most frequently reported adverse events consisted of nasopharyngitis, headache, upper respiratory tract infection, and arthralgia.

Conclusion

Use of brodalumab revealed prompt clinical improvement and a favorable short-term safety profile in phase III trials, although further extension studies are needed to assess long-term safety. Based on the results, brodalumab appears to be a potent therapeutic option for patients with moderate-to-severe plaque-type psoriasis.

Introduction

Interleukin-17 inhibitors are the newest class of monoclonal antibodies approved by the US Food and Drug Administration for the treatment of psoriasis. Preclinical and Phase II studies of ixekizumab, a high-affinity anti-IL-17A monoclonal antibody, have proved promising.

Methods

We conducted an extensive literature search using the PubMed database to assess the efficacy and safety profile of ixekizumab. The search included the following key words: "psoriasis" and "IL-17" or "ixekizumab." We also reviewed citations within articles to identify relevant sources.

Results

By week 12, the percentage of patients achieving a 75% improvement from baseline Psoriasis Area and Severity Index (PASI 75) was comparable among the three Phase III trials (UNCOVER-1, 89%; UNCOVER-2, 90%; UNCOVER-3, 87%). Ixekizumab continued to be efficacious through 60 weeks of treatment. The safety profile of ixekizumab was favorable; the most frequently reported adverse events consisted of nasopharyngitis, upper respiratory tract infection, injection-site reaction, and headache.

Conclusion

Overall, ixekizumab demonstrated rapid clinical improvement and favorable short-term safety profile in Phase III trials. The results support ixekizumab as an effective therapeutic option for patients with moderate-to-severe plaque-type psoriasis.

Psoriasis is a chronic, inflammatory skin disease that affects 2‒3% of the global population. Besides skin manifestations, patients with psoriasis have increased susceptibility to a number of comorbidities, including psoriatic arthritis, cardiovascular disease, and inflammatory bowel disease. To understand the systemic component of psoriasis pathogenesis, we performed a pilot study to examine the fecal metagenome, host colonic transcriptome, and host peripheral blood immune profiles of patients with psoriasis and healthy controls. Our study showed increased functional diversity in the gut microbiome of patients with psoriasis. In addition, we identified microbial species that preferentially associate with patients with psoriasis and which have been previously found to associate with other autoimmune diseases. Intriguingly, our data revealed three psoriasis subgroups that have distinct microbial and host features. Integrating these features revealed host‒microbe associations that are specific to psoriasis or particular psoriasis subgroups. Our findings provide insight into the factors that may affect the development of comorbidities in patients with psoriasis and may hold diagnostic potential for early identification of patients with psoriasis at risk for these comorbidities.

Background

Psoriasis is a chronic immune-mediated disease that affects 2-3% of the world population. Ultraviolet B (UVB) phototherapy is an effective treatment for psoriasis compared to other systemic treatments. Currently there is a lack of easily accessible online patient educational material regarding this form of treatment.

Objective

To present a freely available online guide and video on UVB treatment that is informative to patients and increases the success and compliance of patients starting this therapy.

Methods

The UVB treatment protocol used at the University of California-San Francisco Psoriasis and Skin Treatment Center as well as available information from the literature was reviewed to design a comprehensive guide for patients receiving UVB treatment.

Results

We created a printable guide and video resource that reviews the fundamentals of UV light, UVB safety considerations, flow of treatment, side effects, and post-phototherapy skin care.

Conclusion

This guide serves as a valuable resource for patients preparing for UVB phototherapy, the clinicians who treat them, and trainees wishing to learn more about this form of therapy.

Background

An increasing number of injectable biologics are now available for the treatment of psoriasis. However, for individuals who have never received this therapy, the process of performing a self-injection can be daunting. There is lack of patient educational material on how to perform and optimize this treatment.

Objective

The objective of this study is to present a freely available online guide and video on biologic injections that is informative to patients and increases the success and compliance of patients starting this therapy.

Methods

The self-injection technique taught at the University of California-San Francisco Psoriasis and Skin Treatment Center as well as available information from the literature were reviewed to design a practical guide for patients receiving biologic injections.

Results

We created a printable guide and video resource that describes how to improve the injection process, pain management, travel planning, and common concerns with biologic injectables.

Conclusion

This guide is beneficial for patients who wish to improve their experience with biologic self-injections, for healthcare providers who prescribe these treatments, and for trainees learning about this modality.

IL-17 is involved in the pathogenesis of several autoimmune diseases; however its role in vitiligo has not been well defined. Emerging human and mouse studies have demonstrated that systemic, tissue, and cellular levels of IL-17 are elevated in vitiligo. Many studies have also shown significant positive correlations between these levels and disease activity, extent, and severity. Treatments that improve vitiligo, such as ultraviolet B phototherapy, also modulate IL-17 levels. This review synthesizes our current understanding of how IL-17 may influence the pathogenesis of autoimmune vitiligo at the molecular level. This has implications for defining new vitiligo biomarkers and treatments.

Human skin consists of multiple cell types, including epithelial, immune, and stromal cells. Transcriptomic analyses have previously been performed from bulk skin samples or from epithelial and immune cells expanded in cell culture. However, transcriptomic analysis of bulk skin tends to drown out expression signals from relatively rare cells while cell culture methods may significantly alter cellular phenotypes and gene expression profiles. To identify distinct transcriptomic profiles of multiple cell populations without substantially altering cell phenotypes, we employed a fluorescence activated cell sorting method to isolate keratinocytes, dendritic cells, CD4+ T effector cells, and CD8+ T effector cells from healthy skin samples, followed by RNA-seq of each cell population. Principal components analysis revealed distinct clustering of cell types across samples, while differential expression and coexpression network analyses revealed transcriptional profiles of individual cell populations distinct from bulk skin, most strikingly in the least abundant CD8+ T effector population. Our work provides a high resolution view of cutaneous cellular gene expression and suggests that transcriptomic profiling of bulk skin may inadequately capture the contribution of less abundant cell types.