The invention relates to a method for the investigation of intercellular communication and intercellular transport, wherein after singularisation cells are investigated for membrane tubes which contain F-actin and myosin, have a diameter of 50 to 400 nm, as a rule are up to 50 micrometers long or in same cases longer, and which span between the cells. The invention further relates to a method wherein the organelle transport between the cells is investigated.