Bioprinting is in the vanguard of the war against the novel coronavirus and holds promise for greater understanding of the way SAR-CoV-2 works in the human body. Ultimately, it may aid work in the prevention and treatment of COVID-19, the illness caused by the virus, and demonstrate bioprinting’s potential to reduce animal testing and speed research.
According to published reports, Novoheart Holdings Inc., Irvine, Calif., has created a human ventricular cardiac organoid chamber, referred to as a 3D “heart-in-a-jar,” that’s used to test the effects of potential COVID-19 treatments on the heart; Prellis Biologics, San Francisco, made synthetic lymph nodes that produced virus-specific antibodies when challenged with a SARS-CoV-2 vaccine-like cocktail; and Viscient Biosciences, San Diego, is “moving quickly” to bioprint lung tissue for infectivity research, said CEO George Murphy, previously head of Organovo.
Also intent on bioprinting lung tissues using alveolar bronchial or tracheal epithelial cells is Choi-Fong Cho, assistant professor of neurosurgery at the Harvard Medical School and Brigham and Women’s Hospital, Boston. “Our most widely used model is in animals but there are many differences between a mouse respiratory system as opposed to the human anatomy,” she said. “We aim to use human lung and vasculature cells and create a functional model of the human respiratory system that can mimic and reproduce the organ’s characteristics and functions in a dish. These cells can be grown within an artificial matrix that resembles the lung’s environment to allow us to study their behavior and examine how SARS-CoV-2 affects the respiratory system.”
Cho and research partner Seung-Schik Yoo, associate professor of radiology at Harvard and Brigham and Women’s, would culture the cells in condition media and then use them as bioink that’s printed on a collagen structure in precise locations to reproduce lung and vasculature morphology. “The respiratory and circulatory systems work closely together, meaning that lung tissues are highly vascularized,” said Cho. “We plan to use our bioprinted model to test COVID infection and study how it can affect these systems.”
Eventually, Cho and Yoo would like to use the model to test anti-viral drug delivery, but initially they’d like to figure out if an anti-viral approach applied to the lung tissue would clear out the infection and determine how the viral infection causes blood vessels to behave.
A 3D Bioprinter Demonstration
The Boston investigators reached out to Clecell Co. Ltd., Seoul, South Korea, a startup that created a respiratory epithelium model earlier this year. “Clecell scientists have shared a manufacturing protocol of their airway tissue model with us,” Yoo said in an email.
Clecell expects to develop commercial-grade, bioprinted lung tissue, but the company’s primary focus now is on demonstrating its 3D bioprinter, U-FAB, said Bongsun Kim, chief marketing officer for Clecell. The U-FAB employs 15 multi-channel heads that print 15 types of biomaterials and cells simultaneously or sequentially. Multiple U-FABs can be multiplexed to bioprint complex tissues.
“U-FAB offers dispensing and crosslinking of scaffold biomaterials that allow construction of a 3D, multilayered structure of not only middle and high viscosity, but also low viscosity biomaterials,” Kim said. “The use of low viscosity biomaterials, which cannot be dispensed with conventional extrusion-based printing, opens an avenue for the construction of new breeds of biological tissues.”
Clecell is developing skin models for diagnostic medicine applicable to cosmetics manufacturing, drug functioning and toxicity and virus testing. It also plans to make organoid and regenerative skin models for implantation.