October 2017 Discover

October 2017^ DISCOVER^39

NEAL SCOLDING/SCIENCE SOURCE

This type of stem cell, called an oligodendrocyte

progenitor cell, is found in the brain and spinal cord.

They make myelin, the fatty coating around axons —

long, threadlike fibers that relay neural impulses from

one cell to the next, activating the circuitry that endows

us with the physical and emotional capacity to fully

embrace the world. Scientists believe these neural stem

cells secrete hormonal steroids or proteins that nurse

ailing neurons, preventing them from dying, and stimu-

late the formation of blood vessels that nourish dam-

aged tissue with nutrients and oxygen. They may even

promote new connections between the sickly nerves.

The anesthesiologist had stopped Boesen’s breathing

for those precious few minutes so the movement of his

lungs wouldn’t disturb his spinal cord during the proce-

dure. Liu held his breath, too.

“That was an extremely sobering moment,” he recalls

of those crucial minutes. “We were finally doing human

tests, and what we were doing was based on years of

rational science. This wasn’t just a Hail Mary pass.”

Within a few days of the stem cell procedure, Boesen

was transferred to Keck’s rehabilitation unit. He spent

two months doing three hours of therapy every day,

which included practicing simple daily activities, like

piloting his motorized wheelchair and feeding and

dressing himself. After three weeks, his recovery was

surpassing expectations.

Living in Bakersfield, Calif., with his family, Boesen

can now perform many activities, including hugging his

family and girlfriend. He’s even begun to have sensation

in his knees and thighs.

Patients may regain some feel-

ing or muscle strength when the

swelling of the spinal column goes

down, says Ramzi Ben-Youssef,

medical director of the rehab

unit at Keck. “But when they

gain more than that, you have to

ask yourself what happened here

that did not happen in other cases.

Stem cells combined with inten-

sive therapy may be the answer.”

Boesen leans back in his wheel-

chair in his parents’ airy house.

Appearing in a video made by

USC to demonstrate his capabili-

ties months after the car crash,

he looks dapper in a navy blue

golf shirt and a snug baseball cap

that corrals most of his thick,

dark hair. He fires off a series

of texts, then, using both arms,

lifts a dumbbell high above his

head and returns it to his lap. He

flashes a warm, toothy grin.

He plans to return to work and

is confident he can lead a relatively

normal life. “Thank you,” Boesen

says, staring into the video cam-

era, his face clouding with emo-

tion. “Thank you for allowing me

to live my life again.”^ D

Linda Marsa is a Discover contributing

editor and author of Fevered: How

a Hotter Planet Will Hurt Our Health

and How We Can Save Ourselves.

Oligodendrocytes, in red, create a protective sheath

around nerve fibers in human brain tissue.