Innovative coating for blood vessels reduces rejection of transplanted
organs

Date:
August 9, 2021
Source:
University of British Columbia
Summary:
Researchers have found a way to reduce organ rejection following
a transplant by using a special polymer to coat blood vessels on
the organ to be transplanted. The polymer substantially diminished
rejection of transplants in mice when tested. The discovery has the
potential to eliminate the need for drugs -- typically with serious
side effects -- on which transplant recipients rely to prevent
their immune systems from attacking a new organ as a foreign object.



FULL STORY ========================================================================== Researchers have found a way to reduce organ rejection following a
transplant by using a special polymer to coat blood vessels on the organ
to be transplanted.


==========================================================================
The polymer, developed by UBC medicine professor Dr. Jayachandran
Kizhakkedathu and his team at the Centre for Blood Research and Life
Sciences Institute, substantially diminished rejection of transplants
in mice when tested by collaborators at SFU and Northwestern University.

"We're hopeful that this breakthrough will one day improve quality of
life for transplant patients and improve the lifespan of transplanted
organs," said Dr.

Kizhakkedathu.

The findings were published today in Nature Biomedical Engineering.

The discovery has the potential to eliminate the need for drugs --
typically with serious side effects -- on which transplant recipients
rely to prevent their immune systems from attacking a new organ as a
foreign object.

Dr. Kizhakkedathu explained how that problem arises: "Blood vessels in
our organs are protected with a coating of special types of sugars that suppress the immune system's reaction, but in the process of procuring
organs for transplantation, these sugars are damaged and no longer able to transmit their message." Dr. Kizhakkedathu's team synthesized a polymer
to mimic these sugars and developed a chemical process for applying it
to the blood vessels. He worked with UBC chemistry professor Dr. Stephen Withers and the study's co-lead authors, PhD candidate Daniel Luo and
recent chemistry PhD Dr. Erika Siren.



==========================================================================
Dr. Siren's thinking on cell-surface engineering had been inspired by
a visit to a BC Transplant facility.

"I remember seeing an organ sitting in a solution and thinking,
'Here's a perfect window to engineer something right,'" Dr. Siren
recalled. "There aren't a lot of situations where you've got this
beautiful four-hour window where the organ is outside the body, and you
can directly engineer it for therapeutic benefit." The work of Simon
Fraser University's Dr. Jonathan Choy and Winnie Enns confirmed that a
mouse artery, coated in this way and then transplanted, would exhibit
strong, long-term resistance to inflammation and rejection. Dr. Caigan Du
of UBC and Dr. Jenny Zhang of Northwestern University then got similar
results from a kidney transplant between mice. Dr. Megan Levings of UBC
and the BC Children's Hospital Research Institute firmed up the findings
using new- generation immune cells.

"We were amazed by the ability of this new technology to prevent
rejection in our studies," said Dr. Choy, professor of molecular biology
and biochemistry at SFU. "To be honest, the level of protection was unexpected." The procedure has been applied only to blood vessels and
kidneys in mice so far. Clinical trials in humans could still be several
years away. Still, the researchers are optimistic it could work equally
well on lungs, hearts and other organs, which would be great news for prospective recipients of donated organs.

In 2019, more than 3,000 Canadians underwent organ transplantation with
the aim of averting end-stage organ failure.

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


========================================================================== Journal Reference:
1. Erika M. J. Siren, Haiming D. Luo, Franklin Tam, Ashani Montgomery,
Winnie Enns, Haisle Moon, Lyann Sim, Kevin Rey, Qiunong Guan,
Jiao-Jing Wang, Christine M. Wardell, Mahdis Monajemi, Majid
Mojibian, Megan K.

Levings, Zheng J. Zhang, Caigan Du, Stephen G. Withers,
Jonathan C. Choy, Jayachandran N. Kizhakkedathu. Prevention
of vascular-allograft rejection by protecting the endothelial
glycocalyx with immunosuppressive polymers.

Nature Biomedical Engineering, 2021; DOI: 10.1038/s41551-021-00777-y ==========================================================================

Link to news story: https://www.sciencedaily.com/releases/2021/08/210809112837.htm

--- up 13 weeks, 3 days, 22 hours, 45 minutes
* Origin: -=> Castle Rock BBS <=- Now Husky HPT Powered! (1:317/3)