Increased expression of ficolin-1 is associated with airway obstruction in asthma

Background The activated complement cascade is involved in asthmatic airway inflammation. Ficolins are essential for innate immunity and can activate the complement lectin pathway. Despite this, the significance of ficolins in asthma has yet to be determined. This study aimed to explore the presence of ficolins in individuals with asthma and to determine the relationship between ficolins and clinical characteristics. Methods For the study, 68 asthmatic patients and 30 healthy control subjects were recruited. Enzyme-linked immunosorbent assay was used to determine plasma ficolin-1, ficolin-2, and ficolin-3 concentrations both before and after inhaled corticosteroid (ICS) therapy. Further, the associations of plasma ficolin-1 level with pulmonary function and asthma control questionnaire (ACQ) score were examined in the asthma patients. Results Patients with asthma exhibited significantly elevated plasma ficolin-1 levels (median, 493.9 ng/mL; IQR, 330.2–717.8 ng/mL) in comparison to healthy controls (median, 330.6 ng/mL; IQR, 233.8–371.1 ng/mL). After ICS treatment, plasma ficolin-1 (median, 518.1 ng/mL; IQR, 330.2–727.0 ng/mL) in asthmatic patients was significantly reduced (median, 374.7 ng/mL; IQR, 254.8–562.5 ng/mL). Additionally, ficolin-1 expressions in plasma were significantly correlated with pulmonary function parameters and ACQ score in asthmatic patients. Asthma patients with higher plasma ficolin-1 levels demonstrated poorer lung function than those with lower plasma ficolin-1 levels. Conclusions The results revealed that asthmatic patients had higher plasma ficolin-1 concentrations, which decreased after ICS treatment and were linked to their lung function, implying a potential involvement of ficolin-1 in asthma pathogenesis.