The new research, for Kyoto University, concerns effective ways to delivery drug substances to targeted sites within the human body in a way that ensures the maximum amount of the active ingredient reaches the host cell.
Our cells are rich in proteins which are potential targets for therapy. But study of these proteins’ behavior, using externally delivered biomacromolecules, has often been stymied by the difficulty of gaining access to the interiors of living cells. The new technique involves the delivery of biomacromolecules (which includes antibodies, which are used by the immune system to neutralize pathogens such as bacteria and viruses).
The new process is based on an alteration to a spider venom peptide called ‘M-lycotoxin’. This enables the efficient release of antibodies. For this to happen, the researchers took M-lycotoxin and replaced a substance called a leucine residue with glutamic acid (coded ‘L17E’). It was found that when L17E enters a cell it interacts with cellular membranes, breaking them down to release antibodies.
This new strategy, according to Laboratory Manager magazine, allows medics to track the antibodies using visual imaging. In addition, the process allows antibodies to interact with target proteins, modulating their functions so that immune system efficiency is increased.
Discussing this further, lead researcher Dr. Misao Akishiba explains: “Efficient labeling of intracellular proteins with antibodies allows us to dramatically improve our understanding of their behavior and significance.” The researcher sees the process as leading to new drug treatments, able to transport almost any bioactive macromolecule or nanoparticle into a cell. This will be the subject of further research.
The research has been published in the journal Nature Chemistry. The research is called “Cytosolic antibody delivery by lipid-sensitive endosomolytic peptide.”