Scientists Visualize Perforin, Protector of Body's Immune System

Professor Helen Saibil’s UK team of scientists at Birkbeck College now understands a lot more about a protein called perforin, called our ‘body’s weapon of cleansing and death” by project leader Proessor James Whisstock, from Monash University, Melbourne, Australia.

“Perforin is a powerful bullet in the arsenal of our immune system — without it we could not deal with the thousands of rogue cells that turn up in our bodies through our lives,” says Professor Saibil.

The perforin protein works by punching holes into cells that have been invaded by viruses, including cancer. Toxic enzymes enter the cell structures to kill the viruses.

Professor Whisstock added: “Now we know how it works, we can start to fine tune it to fight cancer, malaria and diabetes.”

Another interesting finding is that the important parts of the perforin molecule are quite similar to those toxins deployed by bacteria such as anthrax, listeria and streptococcus, showing that this method of making holes in cell membranes is quite ancient in evolution. “The molecular structure has survived for close to two billion years, we think,” said Professor Trapani.

Perforin can ‘go crazy’, earmarking the wrong cells for elimination, either in autoimmune disease conditions, such as early onset diabetes, or tissue rejection following bone marrow transplants. via Science Daily