The ability to introduce antibodies to live cells opens new insights to a wide range of applications such as protein intracellular trafficking studies, protein interference studies with blocking antibodies, live immunolabelling or protein phosphorylation states studies.
Apart from scFv antibodies, DNA transfection of eukaryotic cells is rarely used to produce antibodies in situ, mainly due to inappropriate folding of the antibody to the cytoplasm.
Being large proteins, antibodies are unable to cross the plasma membrane by passive transport.
Thus, intracellular delivery of antibodies using a dedicated carrier is a well-suited method representing an innovative approach for cell biologists.
The efficient intracellular delivery of biomolecules with protein carriers requires two crucial steps: crossing the plasma membrane and effective release of the antibody in the cytoplasm.
Using PULSin as an antibody carrier allows an efficient antibody delivery into cytoplasm. Thereafter, delivered antibodies (either primary or secondary antibody) are able to reach their intracellular targets. Relevant data are now available in a various number of eukaryotic cells (see data)
In conclusion, antibody delivery using PULSin represents a novel method where an antibody carrier allows crossing of the plasma membrane without affecting the cell membrane integrity and enables efficient intracellular release of the antibody into the cytoplasm where it diffuses to its target.