Research Seminars @ Illinois

Abstract 

Tendons have a complex hierarchical collagenous structure that provides the tissue with unique tensile load-bearing capabilities essential for proper function. These functional capabilities are established during development within a short window of rapid structural change. While prior work has identified the numerous structural changes that occur during this developmental period (e.g., collagen content, crosslinking, fibril diameter and length), the key structural elements that are responsible for the abrupt increase in tendon mechanical functionality remain unclear. Additionally, the role of mechanical loading and other biological mechanisms during development in driving the observed structure-function changes in tendon are not fully characterized. To address this knowledge gap, we used computational modeling along with ultrastructural imaging, biochemical/thermodynamic assays, and multiscale mechanical testing to comprehensively investigate the dynamic structure-function relationships during late-stage embryonic chick development and to establish their sensitivity to mechanical stimulation. Our results suggest that the rapid increase in multiscale mechanics is primarily due to increases in fibril length, intrafibrillar crosslinking, and fibril area fraction. We also found that both intrafibrillar crosslink formation and fibril elongation are sensitive to mechanical loading. These findings provide critical insights into the biological and structural mechanisms that give rise to tensile load-bearing soft tissues and may help inform tissue engineering strategies to produce tendon/ligament replacements.

About the Speaker 

Dr. Szczesny is an associate professor at the Pennsylvania State University with a joint appointment in the Departments of Biomedical Engineering and Orthopaedics & Therapy Services. He completed his postdoctoral training in 2017 as an NIH NRSA F32 fellow and obtained a PhD in bioengineering in 2015 at the University of Pennsylvania. Prior to his doctorate, Dr. Szczesny developed medical implants as a design engineer for Aesculap Implant Systems and as a research assistant at the Helmholtz Institute for Biomedical Technology in Aachen, Germany. He obtained a MS in mechanical engineering at the Massachusetts Institute of Technology in 2005 and a BS in mechanical engineering at the University of Pennsylvania in 2003. Dr. Szczesny’s research on tendon/ligament mechanics and mechanobiology has been recognized by the 2025 ASME Y. C. Fung Early Career Award, election as an ASME Fellow, a 2022 NSF CAREER Award, 2022 CMBE Rising Star Award, 2016 ORS New Investigator Recognition Award (NIRA) finalist, 2015 Acta Student Award, and two-time winner of the ASME/SB3C PhD competition.

Host: Professor Mariana Kersh