Abstract: The disclosure describes a composition comprising a lipidaceous carrier and a peptide complex formed from poly-L-lysine or a salt thereof; and either poly-L-glutamic acid or poly-L-aspartic acid, or a salt thereof. The composition can be used to prevent or treat a disease related to pulmonary surfactant dysfunction, such as hyaline membrane disease (HMD), respiratory distress syndrome (RDS), hydrocarbon poisoning, near-drowning, HIV/AIDS-related lung diseases, adult respiratory distress syndrome (ARDS) or acute lung injury (ALI), asthma, tuberculosis (TB) or severe acute respiratory syndrome (SARS). Alternatively, the composition can be used to increase the permeability of a pharmaceutical compound or composition across a membrane of a subject or to act as a carrier. The poly-L-lysine or salt thereof is longer than the poly-L-glutamic acid or poly-L-aspartic acid so that the complex that forms has a charge-neutralized region and a positively-charged region.

Abstract: The disclosure describes a composition comprising a lipidaceous carrier and a peptide complex formed from poly-L-lysine or a salt thereof; and either poly-L-glutamic acid or poly-L-aspartic acid, or a salt thereof. The composition can be used to prevent or treat a disease related to pulmonary surfactant dysfunction, such as hyaline membrane disease (HMD), respiratory distress syndrome (RDS), hydrocarbon poisoning, near-drowning, HIV/AIDS-related lung diseases, adult respiratory distress syndrome (ARDS), asthma, tuberculosis (TB) or severe acute respiratory syndrome (SARS). Alternatively, the composition can be used to increase the permeability of a pharmaceutical compound or composition across a membrane of a subject. The poly-L-lysine or salt thereof is longer than the poly-L-glutamic acid or poly-L-aspartic acid so that the complex that forms has a charge-neutralised region and a positively-charged region.