3D Expansion of Hepatocytes Using Novel Microfiber Cell Carriers for Bioprinting Applications
Discipline: Biological Sciences
Subcategory: Biomedical Engineering
Session: 4
Room: 5 - Inman
Mary Jean Savitsky - Florida Agricultural and Mechanical University
Co-Author(s): Sarah Dadey, FAMU-FSU College of Engineering, Tallahassee, FL; Cata Balanzaco, FAMU-FSU College of Engineering, Tallahassee, FL; Navneet Kaur, FAMU-FSU College of Engineering, Tallahassee, FL; Dazhi Yang, Acrogenic Technologies Inc., Rockville, MD; Jamel Ali, FAMU-FSU College of Engineering, Tallahassee, FL
As the primary organ responsible for systemic detoxification, the liver is profoundly impacted by drug toxicity, as observed in drug development studies, preclinical safety assessments, and post-marketing drug evaluations. Current preclinical methods for detecting drug-induced liver injury (DILI) are inadequate, with limited ability to accurately predict a new drug candidate’s potential to cause DILI. This underscores the urgent need for more biomimetic human liver models that effectively replicate the properties of in vivo liver tissue in vitro for drug screening purposes. We hypothesize that a novel microfiber-based hydrogel system will support long-term hepatocyte growth, viability, and in vivo-like functioning in 3D in vitro culture, while also enabling the rapid development of 3D printed liver models for facilitating high-throughput drug screening applications.
We investigates the integration of a microfibrous system into alginate hydrogels to mimic the liver’s mechanical properties and create more physiologically relevant liver models. To evaluate the suitability of the microfibrous biomaterial for 3D printing, we incorporated varying concentrations of the fibrous matrix with 0.7% (w/v) alginate solutions. We then subjected these biomaterial-infused hydrogels to a series of bulk rheological tests to determine their viscoelastic properties which provides information about the biomaterial mechanics, necessary for both printing and recapitulating in-vivo liver biophysical properties. Results show that incorporating microfibrous material into 0.7% (w/v) alginate hydrogels at a 1:9 ratio produces crosslinked hydrogels with a storage modulus of 1 kPa, mimicking the mechanical properties of healthy liver tissue. Increasing the microfiber concentration further enhances the mechanical properties, demonstrating that we have developed a mechanically tunable system suitable for modeling various tissue types with different stiffnesses. Beyond rheological characterization, we also verified the capability to extrude the fiber-laden hydrogels into grid-like structures that maintained their structural integrity, confirming their printability.
Next steps include embedding a human hepatocyte cell line (THLE-2) within the hydrogels to assess cell function, viability, and proliferation over extended periods. Various microscopy techniques will be utilized to evaluate cell growth and morphology within this hydrogel system. This work will aid developing more physiologically relevant biomechanically mimetic liver models, that have strong potential for the rapid development of printable 3D liver models for more precise and efficient drug discovery methods to treat liver diseases.
Funder Acknowledgement(s): This work was funded by the National Science Foundation (No. EES-2306449, EES-2219558) and supported by the NSF FAMU CREST Center award (No. EES-1735968). This research work was also supported by The Grainger Foundation Frontiers of Engineering Grant under the National Academy of Sciences Award Number: 200001318. Support was also provided by the National Institute of General Medical Sciences of the National Institutes of Health under Award Number R16GM145595. All the work was performed at the National High Magnetic Field Laboratory, which is supported by National Science Foundation Cooperative Agreement No. DMR-2128556 and the State of Florida. Mary Jean Savitsky acknowledges support from the Merk Pathways to Successful Biomedical Careers Graduate Fellowship.
Faculty Advisor: Jamel Ali, jali@eng.famu.fsu.edu
Role: I lead all aspects of my dissertation research, including experimental design, data collection, and analysis. I have trained and mentored undergraduate students in the 3D bioprinting techniques central to this project, enabling them to contribute to data collection efforts. My work is conducted under the guidance of Dr. Jamel Ali and with training from Dr. Kaur, a postdoctoral researcher in our lab.