Interaction of holothurian triterpene glycoside with biomembranes of mouse immune cells

► Cucumarioside A2-2 interactions with mouse immune cell biomembranes were studied. ► Glycoside exhibited pronounced immunomodulatory activity in nanomolar concentrations. ► Glycoside effectively increased the microviscosity of the biomembrane lipid bilayer. ► It led to a reversible shift in membrane potential and [Ca2+]i increase in cytoplasm. ► Two binding sites for [3H]-cucumarioside A2-2 on cellular membranes were found.