UCLA Journal of Radiation Oncology January 1, 2022 - Flipbook - Page 8
UCLA RADIATION ONCOLOGY JOURNAL
Eliminating the need for antirejection medication
to their anatomy,” taking special care to avoid
exposing the newly transplanted kidney to
radiation, she says.
Incorporating an infusion of stem cells
from the donor’s blood as part of the organtransplant process works to prevent the
recipient’s body from rejecting the kidney
without the need for immunosuppressive
drugs. The immune systems of the host and
donor live side by side.
UCLA’s new protocol is based on a procedure
successfully performed at Stanford, where
kidney-transplant recipients have survived
without immunosuppressive drugs for 15 years.
Taking the science further
While tolerance has been achieved in
transplants with well-matched sibling donorrecipient pairs, UCLA Health physicians,
in collaboration with OneLegacy, intend to
expand the protocol to include deceased
donors, the source for most of the organs
transplanted in the U.S. Deceased donors
accounted for more than 77% of the 22,800
kidney transplants performed nationally in
2020.
“Stem-cell transplants and solid-organ
transplants are usually conducted very
independently of each other,” says bonemarrow transplant specialist Neil Kogut, MD,
who worked closely with Dr. Veale to develop
UCLA Health’s transplant-tolerance protocol.
“These are very separate worlds that the
doctors and researchers in these fields occupy,”
Dr. Kogut says. “This protocol is a unique
opportunity to bring stem-cell transplantation
and solid-organ transplantation together to
try to achieve something very positive for
transplant recipients. It is a unique synergy of
these two fields.”
If that goal is achieved, “it will have a huge
impact,” Dr. Kogut says. Extending tolerance
transplants to include deceased donors would
allow for other kinds of transplants — from
solid organs to composite-tissue allografts
for hand and faces—to be done without the
necessity for lifelong immunosuppressiondrug regimens.
Radiation therapy plays important
role
Creating tolerance in an organ recipient
also requires radiation treatment to prime
the recipient’s immune system to accept the
donor’s stem cells. Called “total lymphoid
irradiation,” the approach was once employed
to treat Hodgkin’s disease, but it now is used
primarily to minimize the need for posttransplant immunosuppressive drugs, says
radiation oncologist Ann Raldow, MD, MPH,
another member of UCLA Health’s transplanttolerance team.
“It opens up a whole new world,” says Dr.
Veale. ☐
Patients receive the treatment shortly after
their transplant surgery to help prevent graftversus-host disease, Dr. Raldow explains. “The
patients come in before their transplant and we
develop a radiation-therapy plan that is specific
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