Metagenomic Analysis of the Gut Microbiome in Psoriasis Reveals Three Subgroups with Distinct Host-Microbe Interactions

Abstract Background Psoriasis is a chronic, inflammatory skin disease that impacts 2–3% of the global population. Besides skin manifestations, psoriasis patients 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 examined the fecal metagenome, host colonic transcriptome, and host peripheral blood immune profiles of psoriasis patients and healthy controls. Results Our analysis showed increased functional diversity in the gut microbiome of psoriasis patients. In addition, we identified microbial species that preferentially associate with psoriasis patients and which have been previously found to associate with other autoimmune diseases. Intriguingly, our data reveal new insights about psoriasis disease heterogeneity, as we identified three psoriasis subgroups that have distinct microbial and host features. Finally, integrating microbial and host features revealed host-microbe interactions that are specific to psoriasis or particular psoriasis subgroups. Conclusion To our knowledge, this is the first study that provides a comprehensive view of gut microbial function and corresponding host response in psoriasis patients. Our findings provide insight into factors that may affect the development of comorbidities in psoriasis patients and may hold diagnostic potential for early identification of psoriasis patients at risk for these comorbidities.