A new study, led by Irma Joosten, theme Inflammatory diseases, and directly supervised by Hans Koenen, shows that psoriatic patients have a unique neutrophil profile in circulation, and two distinct neutrophil subsets are present in psoriatic skin. The results are published in the Journal of Allergy and Clinical Immunology on the 19th of March.
“Neutrophils are the most abundant leukocytes in humans and their accumulation in lesions of psoriasis is a hallmark of the disease, but whether they have a role in the pathogenesis has remained elusive. Novel insights on phenotypic and functional neutrophil diversity in a plethora of diseases made us wonder about their composition and role in psoriasis”, says Yessica Alina Rodriguez Rosales, PhD candidate at the Laboratory of Medical Immunology.
“By evaluating neutrophil composition and function in blood and skin of 32 psoriatic patients, we defined five neutrophil subsets according to their maturation stage in blood. Interestingly, aged neutrophils were three times more abundant than in healthy individuals. These aged neutrophils displayed suboptimal canonical neutrophil functions but induced IL-17 production by T-cells —mediated by neutrophil extracellular traps— revealing a highly inflammatory profile. Also, in psoriatic skin, mature and aged neutrophils were present, and upon antibody therapy, the numbers of these cells in circulation diminished”, Yessica explains.
Their findings unveil an important role of aged neutrophils in sustaining the inflammatory cycle in psoriatic patients, constituting a steppingstone for additional research on the therapeutic value of this neutrophil subset.
Rodriguez-Rosales YA, Langereis JD, Gorris MAJ, van den Reek JMPA, Fasse E, Netea MG, et al. Immunomodulatory aged neutrophils are augmented in blood and skin of psoriasis patients. J Allergy Clin Immunol. 2021 Mar 19