Abstract
Macromolecules such as proteins or nucleic acids have great potentialities as new "drugs" for the treatment of various diseases. To realize the efficient therapy using macromolecules in the near future, it is required to understand the intracellular fate and to develop the multi-functional carrier system for the regulation of the intracellular trafficking. So far, many efforts have been dedicated to optimize the delivery system of macromolecules. I describe here the intracellular fate of macromolecules delivered with carrier and introduce many approaches for the regulation of the intracellular trafficking of macromolecules, especially for gene therapy.
