Peptide-mediated lipid transport in lung surfactant models: increasing the complexity while lowering the surface tension

Synthetic therapies to treat infant respiratory distress syndrome are urgently needed, as current treatments have stringent storage conditions and are inaccessible in developing countries. We need to understand better how lung surfactant protein B (SP-B) transports lipid between vital lipid reservoirs (when breathing in) to the surface monolayer keeping surface tension close to zero (when breathing out). This proposal builds on a broader project and results from a neutron reflectometry experiment to increase the complexity of the lung surfactant model at more realistic low surface tension values of relevance to lung function. Novelty in the approach is not only the low surface tension but also the selective deuteration of different components of the lipid mixture to highlight the reservoir composition directly with respect to the presence of a peptide analogue of SP-B for the first time.