Background: The host inflammatory response and innate immunity play a complex role in respiratory diseases.
Methods: We evaluated the levels of inflammatory mediators and antibacterial proteins in children who required bronchoscopy and bronchoalveolar lavage fluid (BALF) for clinical indications such as chronic tracheostomy (n=15) and chronic suppurative lung disease (n=8).
Results: Our results suggested the presence of interleukin-1beta (IL-1beta) and IL-8 as major inflammatory mediators in BALF samples. The level of the antibacterial protein sIgA was higher than lactoferrin and lysozyme. BALF IL-8 levels significantly correlated with the presence of IL-1beta, IL-6, IL-10, IL-16, sIgA and lysozyme. BALF IL-8 levels did not correlate with the levels of immunomodulatory and anti-inflammatory clara cell 10 kDa protein (CC10) or lactoferrin.
Conclusion: This study suggests that patients with high levels of BALF IL-8 could potentially have high levels of IL-6, IL-10, IL-16, lysozyme and sIgA. Evaluating the inflammatory mediators (IL-8) in relation to other BALF protein components provides insight into understanding the role of inflammatory mediators in the regulation of host defense and the response to lung inflammation and injury.