PFAPA Hastalarında Behçet Hastaları ile Karşılaştırmalı Olarak NETozis, Düşük Dansiteli Nötrofiller ve Doğal Lenfoid Hücrelerin Değerlendirilmesi.

Abstract

PFAPA (Periodic Fever, Aphthous Stomatitis, Pharyngitis, and Cervical Adenitis) Syndrome is an autoinflammatory disease characterized by recurrent fever, aphthous stomatitis, pharyngitis, and cervical lymphadenitis, primarily occurring in childhood, with an unclear immune pathogenesis. It is known that excessive neutrophil activity, the involvement of neutrophil extracellular traps (NETs) in pathogenesis, and the role of low-density neutrophils (LDNs) and innate lymphoid cells (ILCs) in immune responses are present in inflammatory and autoimmune diseases. The evaluation of these parameters in PFAPA disease is planned. In this study, the contribution of NET production to inflammation will be investigated by measuring NET production in 20 patients diagnosed with PFAPA at the Uludağ University Faculty of Medicine Pediatric Immunology-Rheumatology Clinic, and the percentages of LDN and ILC in the blood will be determined. The findings will be compared with those of Behçet's disease patients and healthy controls. Peripheral blood mononuclear cells (PBMCs) were isolated using density gradient centrifugation, and neutrophils were isolated using the magnetic negative separation method from blood collected during the active phase of the disease from the patients and age-matched controls included in the study. The percentages of ILC subsets and LDNs were determined by flow cytometry, and the level of neutrophil elastase (NE), a marker of NETosis produced by stimulated neutrophils, was measured. The obtained results were analyzed using SPSS and Graphpad software. The ages of the patients (n=20) ranged from 4 to 13 years, with 55% being male and 45% female. In PFAPA patients, more evidence of NETosis was found compared to Behçet's disease patients (p<0.01) and healthy control groups (p<0.0001). While the percentage of LDNs was significantly higher in both disease groups compared to healthy controls (p < 0.0001), the ILC1 level was higher in PFAPA patients than in Behçet's disease patients (p < 0.001 and p < 0.05, respectively). In this study, it was found that NET production, LDN, and ILC1 contribute to inflammation in PFAPA disease. These results suggest that NETosis, LDNs, and ILC1 cells play an important role in the pathogenesis of PFAPA and Behçet's diseases, and understanding these cellular mechanisms is crucial for developing new therapeutic strategies.