LACTOBACILLI INHALATION POWDER FOR THE REDUCTION OF LUNG INFLAMMATION IN non-CF BRONCHIECTASIS DISEASE

An innovative therapeutic approach for the treatment of respiratory diseases is the use of probiotics delivered directly to the lung. After being demonstrated by our group that spray-dried powders for inhalation containing Lpb. plantarum were able to maintain antibacterial activity against P. aeruginosa in vitro, the objective of this work was to investigate their anti-inflammatory activity. Two spray-dried powders containing 109 CFU of lactic acid bacteria (LAB) in 40 mg of powder, with or without a prebiotic, raffinose, were produced. The prebiotic within the formulation allowed to reduce the lag time, i.e. the adaptation time of probiotic to the culture medium, compared to powders without the prebiotic. The powders exhibited a MMAD of about 5 µm, appropriate for their administration in the lungs’ endobronchial region, which is the site of inflammation and infections. The native suspension of LAB was able to significantly reduce the inflammation induced in A549 both if the treatment with LAB was carried out before and after the triggering with LPS. In the case of LAB powders, the anti-inflammatory activity was still significant but to a lesser extent probably due to the slowdown of the cellular metabolism caused by the spray drying process. The work represents a promising starting point to consider the probiotic inhalation powders as a therapeutic alternative for the treatment of the inflammation associated with some respiratory diseases such as non-cystic fibrosis bronchiectasis.