Inflammatory parameters and innate lymphoid cells in chilhood interstitial lung diseases: a prospective study

<bold>Objective:</bold> Childhood interstitial lung diseases (chILDs) are rare, heterogeneous group of disorder. The exact role of inflammation and underlying immune defects in their etiology unclear. Most data derived from in vitro or adult studies, with a noticeable absence of clinical studies in children. Innate lymphoid cells (ILCs) are recognized for their crucial role in lung immunity, extensively studied in asthma but not in chILD. <bold>Methods:</bold> Prospective study, including 20 children with chILD and 19 age-matched controls. Peripheral blood mononuclear cells were separated and analyzed via the flow cytometry method, measuring T regulatory cells (anti-CD4, anti-CD25, anti-CD127), IL-10, and TGFβ within the Treg cell. ILCs 1, 2, and 3 were characterized using anti-CRTH2, anti-CD161, anti-c-Kit, and anti-NKp44 antibodies. T helper cell-17 (TH-17) cells were identified using anti-CD4, anti-CCR6, and anti-IL17A antibodies. <bold>Results:</bold> In peripheral blood, no significant differences were observed in Treg, IL-10, TGFβ, ILCs, TH-17, and IL-17 between the patient and control. However, subgroup analysis revealed a significantly lower ILC2 value in the chILD subgroup than in the control (p=0.037). No significant clinical correlations were found between clinical characteristics, and the investigated immunological parameters. <bold>Conclusion:</bold> This study provides the first comprehensive analysis of extended inflammatory parameters in chILD, including ILCs, found ILC2 lower. Further studies are necessary to comprehend the role of ILCs, how diagnostic and therapeutic interventions may impact the ILCs'function. Additional studies in bronchoalveolar lavage are necessary to elucidate this relationship.