IL-38 in Behçet's disease: Gene expression in bronchoalveolar lavage from patients having pulmonary involvement

• Published in: Immunology letters Vol. 266; p. 106840
• Main Authors: Hamzaoui, Kamel, Louhaichi, Sabrine, Salhi, Mariem, Sassi, Fayçal Haj, Laathar, Ahmed, Hamzaoui, Agnes
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.04.2024
• Subjects: Behcet Syndrome - diagnosis; Behcet Syndrome - genetics; Behçet disease; Biomarkers; Bronchoalveolar Lavage; Gene Expression; Humans; IL-1 family; Inflammasomes; Interleukin-10 - genetics; Interleukin-17 - metabolism; Interleukins - genetics; Lung Diseases; NLR Family, Pyrin Domain-Containing 3 Protein; NLRP3 inflammasome; Pulmonary involvement; Transforming Growth Factor beta - genetics; IL-1 family; Behçet disease; NLRP3 inflammasome; Pulmonary involvement
• ISSN: 0165-2478; 1879-0542
• DOI: 10.1016/j.imlet.2024.106840

•IL-38 was significantly decreased in active BD.•Patients with active BD with pulmonary manifestation, expressed decreased IL-38 mRNA.•Recombinant IL-38 played a regulatory role by suppressing IL-17 and NLRP3 inflammasome in vitro and enhancing IL-10 and TGFβ production in active BD.•Activation of the IL-1 family characterizes the inflammatory process in BD patients with pulmonary manifestations.•Foxp3/RORγt ratio decreased in BAL isolated/derived cells. The etiological complexity of Behçet disease (BD), an immune-mediated rare form of vasculitis characterized by multi-organ involvement, is still elusive due to an incomplete understanding of the synergy between genetic susceptibility, environmental triggers, and an abnormal immune response. The diagnosis of BD relies on clinical symptoms. Lung inflammatory disorders are severe conditions of patients with BD, here we focus on the expression of biomarkers in BD patients with pulmonary manifestations. Aiming to identify additional discriminating biomarker patterns, we measured and compared protein and gene expression of IL-38 and a broad panel of selected genes in bronchoalveolar cells of patients suffering from BD with and without pulmonary involvement compared to controls. ELISA and RT-PCR analysis were applied. The first principal analysis highlighted decreased IL-38 level in BD patients compared to Rheumatoid Arthritis (RA) patients and controls: BD patients expressed lower IL-38 levels, particularly in cases with pulmonary involvement. The area under the curve (AUC) of the receiver-operating characteristic curve showed that IL-38 may be an eventual biomarker for BD. Co-cultured recombinant IL-38 and stimulated memory PBMCs of active BD, were able to suppress IL-17 and NLRP3 inflammasome and ameliorate the secretion of IL-10 and TGFβ. Transcription factors of the IL-1 family (IL-1β, IL-18, IL-32, IL-33 and IL-37) along with IFN-γ, IL-17, RORγt, Foxp3, TGFβ, IL-10 and NLRP3 inflammasome were the parameters that are the main contributor to the segregation between BD with and without lung involvement. Our results indicate that IL-38 might be involved in the pathogenesis of BD and the combined gene expression in BAL suggests distinct mechanisms governing the inflammatory disorders in the lung.