Psoriasis is present in all racial groups, but in varying frequencies and severity. Considering that small plaque psoriasis is specific to the Asian population and severe psoriasis is more predominant in the Western population, we defined Asian small and intermediate plaque psoriasis as psoriasis subtypes and compared their molecular signatures with the classic subtype of Western large plaque psoriasis. Two different characteristics of psoriatic spreading-vertical growth and radial expansion-were contrasted between subtypes, and genomic data were correlated to histologic and clinical measurements. Compared with Western large plaque psoriasis, Asian small plaque psoriasis revealed limited psoriasis spreading, but IL-17A and IL-17-regulated proinflammatory cytokines were highly expressed. Paradoxically, IL-17A and IL-17-regulated proinflammatory cytokines were lower in Western large plaque psoriasis, whereas T cells and dendritic cells in total psoriatic skin area were exponentially increased. Negative immune regulators, such as CD69 and FAS, were decreased in both Western large plaque psoriasis and psoriasis with accompanying arthritis or obesity, and their expression was correlated with psoriasis severity index. Based on the disease subtype comparisons, we propose that dysregulation of T-cell expansion enabled by downregulation of immune negative regulators is the main mechanism for development of large plaque psoriasis subtypes.
Bibliographical noteFunding Information:
We honor Dr. Wook Lew, who first described small plaque psoriasis in the Asian population (2004). We thank psoriasis patients attending Korea University Guro Hospital, Seoul, Korea, and the Rockefeller University Hospital, New York, New York, USA, for donating tissue. Korea University Guro Hospital Biobank facilitated international collaboration between Korea University Guro Hospital and the Rockefeller University. We thank research support from the Translational Technology Core Laboratory (Clinical Translational Science Award, Rockefeller University Center for Clinical and Translational Science, grant no. 8 UL1 TR000043) from the National Center for Advancing Translational Sciences (National Institutes of Health).
Jaehwan Kim, Dong Joo Kim, Joel Correa da Rosa, and Mayte Suárez-Fariñas are supported by the Rockefeller University Center for Clinical and Translational Science (grant no. UL1 TR000043) from the National Center for Advancing Translational Sciences, National Institutes of Health Clinical and Translational Science Award program. Jaehwan Kim, Mayte Suárez-Fariñas, Michelle A. Lowes, and James G. Krueger are supported by the National Psoriasis Foundation Discovery Grant Program. Jaehwan Kim is supported by the Vilcek Foundation. Mayte Suárez-Fariñas is supported by Irma T. Hirschl/Monique Weill-Caulier Career Scientist Award.
© 2015 The Authors.
ASJC Scopus subject areas
- Molecular Biology
- Cell Biology