Cancer-killing T cells 'swarm' to tumors, attracting others to the fight
Immune T cells swarm to tumours by following a chemical gradient left by
other cancer-killing T cells

Date:
October 13, 2020
Source:
eLife
Summary:
When immune system T cells find and recognise a target, they release
chemicals to attract more T cells which then swarm to help subdue
the threat, shows a new study.



FULL STORY ==========================================================================
When immune system T cells find and recognise a target, they release
chemicals to attract more T cells which then swarm to help subdue the
threat, shows a new study published today in eLife.


==========================================================================
The discovery of this swarming behaviour, and the chemical attractants
that immune cells use to direct swarms towards tumours, could one day help scientists develop new cancer therapies that boost the immune system. This
is particularly important for solid tumours, which so far have been less responsive to current immunotherapies than cancers affecting blood cells.

"Scientists have previously thought that cancer-killing T cells identified tumours by randomly searching for them or by following the chemical trails
laid by other intermediary immune cells," says lead author Jorge Luis
Galeano Nin~o, a PhD graduate at UNSW Sydney. "We wanted to investigate
this further to see if it's true, or whether T cells locate tumours via
another mechanism." Using 3D tumour models grown in the laboratory
and in mouse models, the team showed that cancer-killing T cells can
home-in on tumour cells independently of intermediary immune cells. When
the T cells find and recognise a tumour, they release chemical signals,
which then attract more T cells that sense the signals through a receptor called CCR5, and cause a swarm. "These cells coordinate their migration
in a process reminiscent of the swarming observed in some insects and
another type of immune cell called neutrophils, which help the body
respond to injury and pathogens," Galeano Nin~o says.

After confirming their results using computer modelling, the team
genetically engineered human cells called chimeric antigen receptor
(CAR)-T cells and showed they also swarm toward a 3D glioblastoma tumour
grown in the laboratory.

CAR-T cells are currently being used to treat certain types of blood
cancer.

But the new findings suggest that it might also be possible to train
these cells to attack solid tumours.

"Although this is fundamental research and at an early stage, the swarming mechanism could be exploited in the future to target CAR-T cells to
solid tumours, potentially leading to enhanced immunotherapies that are
more effective at infiltrating and destroying these types of tumours,"
says senior author Mate' Biro, EMBL Australia Group Leader at the Single Molecule Science node, UNSW.

"It will also be important to determine whether silencing the swarming mechanism could be beneficial in dampening overzealous T-cell responses following transplant surgery, in autoimmune conditions, or associated
with viral infections," he adds.


========================================================================== Story Source: Materials provided by eLife. Note: Content may be edited
for style and length.


========================================================================== Journal Reference:
1. Jorge Luis Galeano Nin~o, Sophie V Pageon, Szun S Tay, Feyza
Colakoglu,
Daryan Kempe, Jack Hywood, Jessica K Mazalo, James Cremasco,
Matt A Govendir, Laura F Dagley, Kenneth Hsu, Simone Rizzetto,
Jerzy Zieba, Gregory Rice, Victoria Prior, Geraldine M O'Neill,
Richard J Williams, David R Nisbet, Belinda Kramer, Andrew I
Webb, Fabio Luciani, Mark N Read, Mate' Biro. Cytotoxic T Cells
swarm by homotypic chemokine signalling. eLife, 2020; 9 DOI:
10.7554/eLife.56554 ==========================================================================

Link to news story: https://www.sciencedaily.com/releases/2020/10/201013124110.htm

--- up 7 weeks, 1 day, 6 hours, 50 minutes
* Origin: -=> Castle Rock BBS <=- Now Husky HPT Powered! (1337:3/111)