Finally, Sutaria et al. found a distinct cluster of mostly African American PN patients who expressed increased levels of circulating pro-inflammatory cytokines involved in the Th1, Th2, Th17, and Th22 immune axes (IL-1α, IL-4, IL-5, IL-6, IL-10, IL-17A, IL-22, IL-25, and IFN-α) as compared to a cluster with mostly Caucasian PN patients18. Here, IL22 is linked to poikiloderma with neutropenia.