Guns and genes

USING one of nature's amazing biological postmen - the harmless sendai virus (discovered in Japan some 50 years ago) - Delhi University biochemists have come up with an injectible system for targeted drug delivery, bringing themselves a step closer to developing a tool for gene therapy.

Experimenting with the virus, the scientists were able to aim potent drugs at human liver cancer cells in a test tube; successful tests on rats have also been carried out. The team is now trying to arm the guided missile with genes and use it as a gene gun for curing inherited ailments like diabetes mellitus. The senclai carries a fusion protein which helps it home in on target liver cells. The scientists developed a modified form of the virus, named F-virosome, which can be packed with the desired genes and launched through the blood stream; the virosome then seeks the target cell, fuses with the cell wall and micro-injects its contents into the cell's cytoplasm.