By Edwin L. Aguirre
Chemical engineering Asst. Prof. Gulden Camci-Unal and her team of student researchers are combining old technologies with cutting-edge tissue engineering to design new biomaterials that could someday be used to repair, replace or regenerate skin, bone, cartilage, heart valve, heart muscle and blood vessels, among others. This research could help alleviate the acute shortage of tissue and organ donors.
Using origami – the Japanese art of paper folding – as inspiration, Camci-Unal and her team are using plain paper to create tiny scaffoldings where the biomaterials can grow, and then applying microfabrication techniques to engineer new tissues.
“Paper is a low-cost, widely available and extremely flexible material that can be easily fabricated into three-dimensional, or 3-D, structures of various shapes, sizes and configurations,” says Camci-Unal.
The team uses origami-folded paper to grow bone cells, called osteoblasts, which produce the matrix that gets deposited with minerals to form bone. The paper can then be implanted to treat patients with bone defects of irregular sizes and shapes, or those with tissue damage caused by disease or trauma. Based on the results of their experiments with animal models, Camci-Unal notes, the implants are biocompatible – that is, they are not expected to be rejected by the body’s immune system.
In another study, the researchers use layered paper structures to investigate in 3-D the migration behavior of lung cancer cells taken from patients.
“Tumor biopsies from patients can be grown in our system, and then these cells can be exposed to different chemotherapy drugs or radiation doses to find out which specific treatment would work best for the patient,” explains Camci-Unal, who had worked at MIT, Harvard University and Harvard Medical School before joining UMass Lowell in 2016.
The research is supported by UMass Lowell, UMass Medical School and the U.S. Department of Defense.
Combining Hydrogels with Paper Scaffoldings
In addition to paper, Camci-Unal also works with hydrogels – Jell-O-like flexible and squishy materials made up of mostly water that can be used as tissue models.
“Their physical, chemical and biological properties can be tailored to fit in various tissue engineering applications,” she says. “However, hydrogels have relatively weak mechanical properties, so they tend to be not as easy to handle and manipulate when they are in large, very thin sheets.”
By combining hydrogels laden with cells with stacked sheets of paper, Camci-Unal is able to create sufficiently strong support structures that can be used for tissue engineering. Other investigators have developed 3-D structures from synthetic materials like polymers, ceramics and metals to culture cells, but they do not closely resemble the surroundings in native tissues.
“Our team is now starting to get involved in wound-healing research, too,” says Camci-Unal. “Our ultimate goal is to improve human health and the quality of life.”
Camci-Unal and three of her students – Ph.D. candidates Xinchen Wu and Sanika Suvarnapathaki of the biomedical engineering and biotechnology (BMEBT) program and biology major Kierra Walsh – discussed the use of paper-based 3-D platforms for cell cultures and other biomedical applications in a Jan. 24 article in “MRS Communications.” The peer-reviewed journal, published by the Materials Research Society, is used by researchers worldwide for the rapid dissemination of breakthroughs in materials science.
Other members of the research team include master’s students Darlin Lantigua (BMEBT) and Amrita Singh (biology) and undergraduate students Michelle Nguyen (biomedical engineering), Brianna Hoff (chemistry) and Seongjin Kwon, Akhil Meka and Shainlee Taing (all of biology).