Growing Artificial Organs: Medicine's Next Big Thing?
BOSTON, Mass. (Ivanhoe Newswire) – When you think of 3D, you think movie and video games, but researchers are using 3D printing to customize medical implants and to grow body parts. Researchers are now developing three new breakthroughs that could change medicine in the future.
It looks like a beating heart, but it's actually cardiac cells—bioengineers are using them to create artificial tissues and organs. Submit
"If you have a failing organ, maybe we can replace a portion of the organ with a tissue construct we grow in the lab," Mehmet R. Dokmeci, PhD, Instructor in Medicine, Brigham and Women's Hospital, told Ivanhoe.
The cells are grown on a hydrogel. By exposing a per-polymer solution to UV light, researchers create a micro-scale, cell loaded building block.
That same team is working on DNA glue that assembles these building blocks to make larger tissues that will someday be used as artificial organs.
"You want to create thicker, larger tissue structures. So by taking these different micro-gel blocks and assembling them together, you can really create thicker bigger tissue structures," Dr. Dokmeci said.
The team is also using a 3D printer to create tissue to be used for customized implants.
Layer after layer of biomaterials create implantable tissues. The living 3D structure could someday help replace organs specifically designed for their patients.
The team hopes in the next five to ten years the research will become a medical reality.
3D PRINTING: Dying patients could someday receive a 3D printed organ made from their own cells rather than wait on long lists for the short supply of organ transplants. Universities and private companies have already taken the first steps by using 3D printed technology to build tiny chunks of organs. Regenerative medicine has already implanted lab-grown tracheas, skin, and bladders into patients. In comparison, 3D printing technology offers living cells layer by layer to make replacement skin, body parts, and perhaps eventually organs like livers, hearts, and kidneys. (Source: www.livescience.com)
7 USES OF 3D PRINTING IN MEDICINE: 3D printing may seem like science fiction, but real scientists are actually using 3D printing in ways that could revolutionize medicine.
- Printing Human Embryonic Stem Cells: Stem cells can now be printed in the lab. In a study published Feb. 5th, 2013, in the journal Science, researchers from the University of Edinburgh describe a valve-based cell printer that spits out living human embryonic stem cells. The cells could be used to create tissue for testing drugs or growing replacement organs.
- Printing Blood Vessels & Heart Tissue: Printing some types is already a reality. Gabor Forgacs from the University of Missouri in Columbia and colleagues printed blood vessels and sheets of cardiac tissue that "beat" like a real heart. A group of researchers at the German Fraunhofer Institute has also created blood vessels, by printing artificial biological molecules with a 3D inkjet printer and zapping them into shape with a laser.
- Printing Skin: The last 25 years have seen great advances in creating tissue-engineered skin, which could be used to replace skin damaged from burns, skin diseases, and other causes. Lothar Koch of the Laser Center Hannover in Germany and colleagues laser-printed skin cells.
- Patching a Broken Heart: Researchers are now developing a "heart patch" made of 3D printed cells that could repair damaged hearts. Researchers at the University of Rostock, Germany, created a patch using a computerized laser-based printing technique. They implanted patches made of human cells in the hearts of rats that had suffered heart attacks; the rats' hearts that were patched showed improvement in function.
- Printing Cartilage & Bone: In 2011, the same group from Germany that made the skin used laser printing to create grafts from stem cells that could develop into bone and cartilage.
- Studying Cancer with Printed Cells: Printing cells could lead to better ways of studying diseases in the lab and then developing therapies. For example, researchers used an automated system to print ovarian cancer cells onto a gel in a lab dish where the cells could be grown and studied.
- Printing Organs: Ten years ago, Anthony Atala, who directs the Wake Forest Institute for Regenerative Medicine, took stem cells from a patient with a failing bladder, grew a new bladder, and transplanted it into the patient. His more recent efforts have focused on printing organs, and he has since demonstrated an early experiment to print a transplantable kidney. (Source: www.livescience.com)
Mehmet R. Dokmeci, PhD, Instructor in Medicine, Brigham and Women's Hospital, talks about growing body parts in the lab.
So you're doing a lot of research here. One of the things that you are working on is hydrogel. Can you tell us about what that is?
Dr. Dokmeci: What we are doing is creating tissue constructs for tissue engineering and regenerative medicine applications. If you have a failing organ, then we might replace a portion of the organ with the tissue construct that we grow in the lab. Cells are the basic building blocks, and by mixing them with hydrogels to create thicker structures for tissue replacement. That could be a cardiac patch or patches for different organs. Rather than replacing the entire organ where there is an organ shortage, we can replace a portion of it; take a chunk out and then put the replacement part in.
What is a hydrogel?
Dr. Dokmeci: Hydrogel is a polymer that we use to encapsulate cells, to create thicker tissue structures. It is similar to the gelatin, or Jell-O, that you buy from the store.
What do you do with the hydrogels?
Dr. Dokmeci: We can encapsulate cells inside to create thicker three dimensional structures. We can bio-print them. The basic advantage of hydrogels is that they're porous allowing cells to breathe and to receive nutrients they're compatible with cells that are being encapsulated inside. The liquids, nutrients, and gases can go inside and diffuse out so it creates a healthy environment for the cells to survive.
What do those cells eventually turn into?
Dr. Dokmeci: Those cells go into the specific organ and then fix the organ, like patching a tire.
Do you also do the 3D printing with the hydrogels?
Dr. Dokmeci: Yes. To create thicker structures, we can put monolayers on top of each other. For instance, in the body of different cell types, using different cell-laden hydrogels you can create cell type A, cell type B, cell type C, and create really larger structures. It's very difficult to create multilayer thick tissue constructs, and very easy to do 2D monolayers, yet in the body all tissues have a 3D architecture.
Bio-printing is a method to create thicker structures by putting layer by layer on top of each other. Dimensions we are talking about can be up to a millimeter or more.
Why would you want to create the 3D printing? What's the benefit for a person or a patient?
Dr. Dokmeci: We want to do it for regenerative medicine applications. If you're replacing a certain part of a tissue, you may want to create not a monolayer, but a multilayer, maybe a millimeter size construct. You can make large pieces in a rapid manner.
How does this help a doctor if they were performing some sort of treatment or surgery?
Dr. Dokmeci: If an organ is failing, he/she may want to replace it. If part of an organ is failing, maybe you can take that part off and then replace it with a tissue construct that we grow in the lab. For a cancer patient maybe you take a certain part of the liver or the lung, but you don't want to leave a hole there, so you could patch it with the cell-laden hydrogel construct. Over time, cells release certain molecules to degrade the hydrogel; and tofill the block as the hydrogel degrades. So, the organ would be a functional and a large organ again.
Can you talk about the DNA glue you are using?
Dr. Dokmeci: In addition to bio-printing, there are other means to create 3D tissue structures. In the first step, we create small cell loaded Microgel blocks with dangling DNA molecules from each side. The goal is to attach these blocks together. We use DNA hybridization where the complementary units of DNA allow the assembly of the microgel blocks to create larger structures. DNA in a sense acts as a glue to hold the parts together and helps in guiding the directionality of the assembly.
Why would somebody want this?
Dr. Dokmeci: The typical cell culture is a monolayer, single layer culture which is not really amenable to implantation or for tissue replacement. You want to create thicker, larger tissues structures so by taking these different Microgel blocks and assembling them together, we can really create thicker, bigger tissue structures. Then, that goes to the patient and replaces the failing organ or a cancer tissue.
FOR MORE INFORMATION, PLEASE CONTACT:
Lori J. Schroth
Manager, Media Relations, Communication & Public Affairs
Brigham and Women's Hospital