cancer cells (blue)
Image courtesy of Gillian
Griffiths and Jonny Settle
New research has illuminated the behavior of cytotoxic T cells (CTLs) as they hunt down and eliminate cancer cells.
Investigators used novel imaging techniques to capture the process on film and described their findings in an article published in Immunity.
The team captured the footage through high-resolution, 3D, time-lapse, multi-color imaging, making use of both spinning disk confocal microscopy and lattice light sheet microscopy.
These techniques involve capturing “slices” of an object and “stitching” them together to provide the final 3D images across the whole cell.
These approaches allowed the investigators to determine the order of events leading to the lethal “hit” CTLs deliver to cancer cells.
“Inside all of us lurks an army of ‘serial killers’ whose primary function is to kill again and again,” said study author Gillian Griffiths, PhD, of the Cambridge Institute for Medical Research in the UK.
“These [CTLs] patrol our bodies, identifying and destroying virally infected and cancer cells, and they do so with remarkable precision and efficiency.”
The CTLs, seen in the video as orange or green amorphous “blobs,” move around rapidly, investigating their environment as they travel.
When a CTL finds a cancer cell (blue), membrane protrusions rapidly explore the surface of the cell, checking for tell-tale signs that this is an uninvited guest.
The CTL binds to the cancer cell and injects cytotoxins (red) down microtubules to the interface between the T cell and the cancer cell, before puncturing the surface of the cancer cell and delivering its deadly cargo.
“In our bodies, where cells are packed together, it’s essential that the T cell focuses the lethal hit on its target,” Dr Griffiths explained. “Otherwise, it will cause collateral damage to neighboring, healthy cells.”
“Once the cytotoxins are injected into the cancer cell, its fate is sealed, and we can watch as it withers and dies. The T cell then moves on, hungry to find another victim.”
The investigators’ video is available on YouTube.
