Probing the interaction between heparan sulfate proteoglycan with biologically relevant molecules in mimetic models for cell membranes: A Langmuir film study

► Syndecan-4 was incorporated in lipid monolayer. ► Cell culture that over-expresses syndecan-4 expands lipid monolayers. ► Growth factor interacts with sulfate in heparan chains. ► This interaction relaxes the DPPC monolayer. ► The monolayer becomes more condensed.