Fitness Files: 3D printers could take transplants to new level

“Read this.” My husband handed me the May 2015 Smithsonian.

Matthew Shaer’s article, “The Body Shop,” expands on the use of the 3D printer in medicine and describes other strategies for organ replacement.

The May 1 Fitness Files featured Dr. Jaime Landman, UC Irvine’s chairman of the Department of Urology, who suggested that in the future 3D printers could be used to produce disposable surgical tools.

In the Smithsonian article, Shaer visited Wake Forest Institute for Regenerative Medicine in Winston Salem, N.C., to look at bioprinters that have the capability of printing “something that’s alive.”

Let’s say the patient needs skin, a bone or a bladder. Modeling software scans an object, generating data for the printer, which uses biocompatible plastic “to lay down successive coats of matter until a three-dimensional object is formed.”

For example, the article says, surgeons humanely removed a patch of skin from a pig. To replace the skin, the printer formed the interlocking structure, or skin scaffold, “to be filled with a gel containing cells or proteins to promote their growth. As the scaffold was created, cells from the pig were printed on it. The structure was placed in an incubator, the cells multiplied and the ‘printed’ skin was implanted on the pig.”

Now there’s a pig running around the lab with a printed square of skin, a bit different in color but warm and living.

The future for humans lies in the production of rejection-proof organs. All the biological material comes from the patient, so what’s to reject?

As Shaer watched, the machine printed a human ear. Though not yet implanted on human subjects, successful implantations of “printed” ears, bone, and muscle exist on living animals.

Dr. Anthony Atala, a pediatric urologist who trained at the University of Louisville and the Harvard Medical School, says, “We’re getting close with ‘simple’ organs like skin, the external ear and the tube-like trachea.”

Currently, the supply of needed organs for hospitalized patients is not meeting the demand. Shaer quotes the U.S. Department of Health and Human Services: “Twenty-one people die every day in this country alone waiting for an organ.”

Atala said, “The solution to the organ donor shortage is the creation, in a lab, of replacement parts.”

Atala is no stranger to bioengineered body parts. Seven years ago, before bioprinters, he hand-stitched a scaffold for a human bladder replacement. He used the cells of a potential patient, multiplied them in the lab, applied them to the scaffold and incubated the organ. For the first time in history, lab-grown bladders were successfully transplanted into seven young spina bifida patients. Seven years later, the organs still functioned.

Despite all the excitement around the functioning bladders, the U.S. Food and Drug Administration approval process moves so slowly that the replacement bladder has not been approved for wide use.

Slow FDA approval is only one problem in organ replacement. Atala got himself in trouble during a Ted Talk when he displayed a printed human kidney. Some said he was too hasty in representing a printer-made kidney. While it is true that the kidney is an often-needed transplant organ, it is a complicated combination of teeny blood vessels, a million nephrons and a vasculature fed by blood and nutrients.

So Texas Heart Institute’s Dr. Doris Taylor, an expert in regenerative medicine research, is experimenting with animal organs. She reportedly strips the organ of muscle and other living tissue, leaving only the underlying collagen matrix.

The collagen matrix forms a sterile “interior architecture” of the organ. The structure remaining after tissue removal is repopulated with the patient’s cells.

So far, Taylor has used decellularized pig hearts, repopulated them with bovine cells, which function inside cows alongside their own hearts.

Hey, it’s a start.

According to kidney.org‘s organ donation and transplantation statistics for 2014, 123,175 people are waiting for lifesaving organ transplants in the U.S. Of these, 101,170 need kidneys. Twelve people die each day awaiting kidney transplants. What relief families and patients would experience if a non-rejecting kidney was printable or decellularized.

People like Landman, Atala and Taylor push the limits of technical creativity in order to solve medical misfortunes and save lives.

Newport Beach resident CARRIE LUGER SLAYBACK is a retired teacher who ran the Los Angeles Marathon at age 70, winning first place in her age group. Her blog is lazyracer@blogspot.com.