Researchers at the Imperial College London and the University of Oxford are reporting in the journal PLoS Biology that they can see the inner workings of white blood cells at the highest resolution ever documented.
To do this, the team immobilized a white blood cell using a pair of optical laser tweezers and watched with a super-res microscope as the so-called Natural Killer cell's actin filaments parted, creating a tiny portal through which enzyme-filled granules passed to kill targeted diseased tissue.
If you think the resulting image (at right) doesn't look super-res, consider the zoom. The place where an NK cell and its target touch is about a hundredth of a millimeter wide, and the tiny actin proteins and granules are doing something of a dance, constantly changing position over the few minutes from initial contact to the death of the target. The microscope has to be super high-res and fast.
"These previously undetectable events inside cells have never been seen in such high resolution," said Alice Brown, from the Department of Live Sciences at Imperial College London, in a news release. "It is truly exciting to observe what happens when an NK cell springs into action."
The team reports that the ability to watch this activity could have implications for targeted medical treatments and even bone marrow transplants.
"[Natural Killer] cells are important in our immune response to viruses and rogue tissues like tumors," said Professor Daniel Davis, from the Department of Life Sciences at Imperial College London. "They may also play a role in the outcome of bone marrow transplants by determining whether a recipient's body rejects or accepts the donated tissue."