Author: Steven Ayala

Congratulations to Emily, Stephen and their other co-authors on their accepted manuscript in Acta Biomateriala titled “Proteoglycan Removal by Chondroitinase ABC Improves Injectable Collagen Gel Adhesion to Annulus Fibrosus”. The article describes the use of chondroitinase to remove proteoglycans from the surface of annulus fibrosus tissue to increase the adhesion of annular repair therapies. Emily is an undergraduate student at Cornell studying biomedical engineering about to enter her senior year, and Stephen is a PhD student in biomedical engineering in his fifth year. Congrats!

Figure1: ChABC Graphical Abstract

Sierra Cook passed her B Exam and received her PhD in Applied and Engineering Physics. Congrats, Sierra!

Nicole Diamantides passed her B Exam and received her PhD in Biomedical Engineering. Her doctoral thesis was entitled “Development of Collagen Bioinks for Cartilage Bioprinting” and focused on tuning chemical, biological, and mechanical properties of collagen gels to enable their use as inks for 3D tissue printing. After receiving her PhD, Nicole will become an Application Specialist at Cellink, Co. in Boston, MA. Congrats, Nicole!

Jongkil Kim passed his A Exam and received his M.S. in Biomedical Engineering. Congrats, Jongkil!

Jill Middendorf passed her B Exam and received her PhD in Mechanical Engineering. Congrats, Jill!

Hao Zhou passed his M Exam and received his M.S. in Materials Science. Congrats, Hao!

Liz Feeney placed 3rd in the PhD Student Paper Competition at the Summer Biomechanics, Bioengineering, and Biotransport Conference (SB³C) for her paper entitled “Inflammatory and Non-Inflammatory Synovial Fluids Exhibit Distinct Tribological Phenotypes.”  Her work compared the lubricating behavior of synovial fluid from patients with inflammatory and non-inflammatory arthritis.  She found that a sub-population of patients with inflammatory arthritis had unusually poor lubricating properties and that this population was also deficient in lubricin, a glycoprotein found in synovial fluid and on the surface of cartilage. Synovial fluid from this unusual population of patients did not benefit from the addition of hyaluronic acid, a commonly used injectable arthritis therapy.

Results from this study can be used to better understand the basic process of cartilage lubrication and to inform targeted therapies for specific populations of arthritis patients.  Congratulations to Liz and her co-authors!

A paper from the Bonassar lab was featured on the website Science Daily.  The manuscript, published in PLOS ONE, is titled “Frictional characterization of injectable hyaluronic acids is more predictive of clinical outcomes than traditional rheological or viscoelastic characterization.” The paper sheds new light on an ongoing debate over the mechanism of action of injectable hyaluronic acid therapies that are used for arthritis treatment. Over 1 million such injections are given in the US per year at a total cost of $1 billion. Such injections have been considered Class III medical devices for decades. Recently the FDA announced that it would consider reclassifying such injections as drugs because of potential biological mechanisms of action of hyaluronic acid. The new paper demonstrates that the clinical outcomes associated with these products are highly correlated with the ability to lubricate cartilage, indicating that mechanical mechanisms are likely still very important to their activity. Notably, traditional methods of assessing the viscosity of hyaluronic acid formulations are not predictive of clinical performance, but direct measurements of their ability to lubricate cartilage are predictive.

Additionally commentary from Prof. Bonassar about this paper can be found at Science Daily (https://www.sciencedaily.com/releases/2019/06/190604101638.htm).

The first author, Dr. Eddie Bonnevie, received his PhD in Mechanical Engineering from Cornell University, working in the Bonassar lab to understand new mechanisms of cartilage lubrication. He is currently a postdoctoral fellow at the McKay Research Laboratory in the Department of Orthopaedic Surgery at the University of Pennsylvania. Congratulations to Eddie and his co-authors!

Louis Wang, an undergraduate researcher in the Bonassar Lab, won the award for best poster among the honor thesis projects in the Department of Materials Science and Engineering.  His poster, titled “Improving the Printability of Collagen Bioinks by Controlling Surface Hydrophobicity” describes his investigation of the role of surface hydrophobicity on the deposition of collagen bio-inks for 3D tissue printing.  He showed that hydrophobic coatings can increase the printability of collagen bioinks by up to 50%, and that some critical combination of viscosity and hydrophobicity is necessary to create accurate prints.

Louis is will be earning his BS in Materials Science and Engineering from Cornell at Commencement on May 26.  After graduation he will be enrolling in the PhD program in Materials Science and Engineering at Stanford University. Congratulations, Louis Wang!

A figure from an upcoming publication from the Bonassar lab is featured as the frontpiece ofAdvanced Healthcare Materials. The manuscript by Iannucci et al, is titled “Cellular and Chemical Gradients to Engineer the Meniscus-to-Bone Insertion” and is published in the July issue of Advanced Healthcare Materials, which focuses on biological interfaces.  The paper describes the use of customized bioreactors and patterned deposition of mesenchymal stem cells and meniscal fibrochondrocytes to achieve more accurate and mechanically robust reconstruction of the meniscal enthesis, which anchors the meniscus to the tibia.  The frontpiece image (see below and online at https://onlinelibrary.wiley.com/doi/10.1002/adhm.201970027) is a confocal reflectance micrograph showing fibrochondrocytes (green) and mesenchymal stem cells (red) interacting with a collagen matrix (yellow).

The first author, Leanne Iannucci, completed her BS and MEng degrees at Cornell University, working in the Bonassar lab to develop new methods to engineer hard-to-soft tissue interfaces.  She is currently a PhD student in Biomedical Engineering at Washington University in St. Louis studying soft tissue biomechanics.  Congratulations to Leanne and her co-authors!