Presentation: 2025 ND EPSCoR Annual conference 

October 21, 2025, NDSU Memorial Union, Fargo, North Dakota

Cellular response of biomaterials and scaffolds for ACL repair

Anterior cruciate ligament (ACL) injuries affect athletes, laborers, and military personnel at high rates, with over 400,000 reconstructions annually in the United States. Traditional autograft-based reconstructions carry significant limitations, including donor-site morbidity, extended recovery, and elevated osteoarthritis risk, motivating the search for graft-sparing alternatives. In this study, we utilized previously developed nanoclay/collagen composite scaffolds to investigate their ability to support mesenchymal stem cell (MSC) differentiation toward a tenocyte lineage. MSCs were seeded onto porous, aligned scaffolds and cultured either in complete medium without growth factor supplementation or in medium supplemented with TGF-β1 and BMP12. Constructs were analyzed at days 7, 15, and 23 to assess cell viability, proliferation, extracellular matrix (ECM) deposition, and tenogenic differentiation. Tenocyte identity was confirmed through gene and protein expression of key markers, including scleraxis (SCX) and tenomodulin (TNMD). Comparative analysis revealed scaffold–culture conditions that most effectively promoted tenogenic marker expression while maintaining favorable cell behavior. These findings demonstrate that MSCs can undergo tenogenic differentiation on nanoclay/collagen scaffolds, highlighting the potential of this cell–material system as the foundation for a graft-sparing ACL replacement strategy that may improve functional outcomes following ligament injury.