PhD Candidate, Department of Biomedical Engineering
Rochester Institute of Technology

Graduate Degree: M.Sc. in Health Science and Technology, ETH Zurich, Switzerland

Undergraduate Degree: B.Sc. in Health Science and Technology, ETH Zurich, Switzerland

Who do you consider your mentors?

I am happy to name my Ph.D. advisor, Dr. Karin Wuertz-Kozak, as my mentor. I greatly benefited from her guidance and mentorship, which shaped my development and has led me to be the independent researcher I am today. I also count my lab members as mentors, particularly those who provide scientific or personal advice and train me in new techniques. I also benefited from mentors during my master’s thesis at the AO Foundation, where my interest in musculoskeletal research and regenerative medicine was first sparked. Their mentorship is clearly one reason for my decision to pursue a Ph.D. I have been overall very fortunate to learn from several mentors throughout my academic and professional journey.

What is your specific area of interest in research?

My research focuses on mechanobiology and intervertebral disc degeneration of the annulus fibrosus. I am very interested in understanding how cells sense and respond to mechanical cues through mechanosensitive ion channels such as TRPV4, and how we can connect the underlying mechanisms to disc health and disease. Apart from cell biology, I am also interested in (bio)materials and organ models, as these are important for investigating more complex mechanisms of disc diseases and for studying the role of mechanosensitive channels in a more physiological way.

What are you currently working on?

I am currently working on the role of TRPV4 in mechanotransduction in annulus fibrosus cells and whether this mechanosensitive ion channel contributes to IVD degeneration. To investigate this, we use a polydimethylsiloxane (PDMS) based substrate model to better mimic a physiological mechanical environment of intervertebral discs. I apply pharmacological approaches to modulate TRPV4 activity, including activation and inhibition, as well as mechanical stimulation.

What has been the biggest challenge for you lately in your research?

One of the biggest challenges lately has been to carefully interpret my dataset to define the next direction of my project. Naturally, research is rarely straightforward, and experiments do not always go as expected. In addition, the biological variation can make it difficult to draw clear conclusions. That’s why I reevaluated the data, slightly shifted the focus of the experiments, and explored different approaches to ensure the conclusions were supported by the data. Although it was cumbersome, I learned to stay consistent and resilient.

What projects are you looking forward to?

I am looking forward to completing the current phase of my project and continuing to look at how mechanical cues, particularly substrate stiffness, influence annulus fibrosus cell behavior. I am interested in connecting it to mechanosensitive cell signaling mediated by TRPV4 and investigating whether it is linked to IVD degeneration.

What changes would you like to see in the future of the orthopedic research community?

I would definitely like to see increased collaboration between different areas such as cell biology, biomaterials, and biomechanics. I hope this will promote the development of more advanced in vitro models for testing novel regenerative approaches. I would be very pleased to see novel regenerative treatments actually implemented into clinical practice that can slow, halt, or even reverse IVD degeneration.

I would also love to see ongoing opportunities for young scientists to be more involved in the ORS spine community.

What do you like to do outside of your work?

I am passionate about research, which naturally takes up a large amount of my time and energy. Because of that, I find it important to also step away from the lab and experiments and return with a fresh perspective. To recharge, I enjoy staying active and spending time outdoors, such as going for runs. During winter, I occasionally convince myself to go to the gym, and I also joined a university soccer team with friends, where we play against other teams for fun.

I also enjoy traveling, exploring new places, and treating myself with good food.

What is the last book you read?

I have to admit that I am not very enthusiastic about books; reading articles keeps me already busy enough. That’s why it has been a while since I last read a book. However, the most recent one I read was “Fuer immer die Alpen” by Benjamin Quaderer. What made the book meaningful to me was the personal connection, as the author is a relative, and the very interesting story connected to my home country.

What is the most unusual/unexpected item sitting on your desk right now?

Probably cheap instant coffee that expired almost two years ago. That might be surprising because I really like good coffee, but when I have no other option, I still drink it.

Chondroitinase Versus Papain Digestion Leads to Different Outcome for In Vitro Simulation of Degenerated Discs

Jan Ulrich Jansen, Graciosa Quelhas Teixeira, Elias Salzer, Andrea Vernengo, Sibylle Grad,
Keita Ito, Cornelia Neidlinger-Wilke, Hans-Joachim Wilke
(*Authors in bold represent Spine Section Members)

https://onlinelibrary.wiley.com/doi/epdf/10.1002/jsp2.70164

Brief introduction of the topic

Intervertebral disc degeneration (IVDD) is a major contributor to low back pain (LBP). It is characterized by increased cell death and extracellular matrix (ECM) breakdown, leading to biomechanical changes. Developing regenerative therapies relies on preclinical in vitro models. Bovine functional spine units (FSU) received increasing attention due to their availability and low ethical concerns. However, healthy FSUs cannot recapitulate the IVDD environment. Therefore, researchers commonly use enzymatic tissue digestion with papain or chondroitinase ABC (chABC). While papain is more widely reported in literature, the biomechanical and macroscopic appearance of chABC remains understudied. Evidence suggests that chABC better mimics physiological IVDD and may be more useful for studying novel therapeutic approaches.

Brief paragraph on methods

Bovine FSUs were assigned to fresh, sham, chABC, or papain treatment groups. Degeneration was induced by intradiscal enzyme injection followed by seven days of culture and a complex loading to compensate for tissue swelling. The degree of degeneration was assessed through biomechanical testing, including range of motion (ROM), neutral zone (NZ), disc height, and macroscopic tissue appearance. The authors further applied a translational approach of injecting a radiopaque serum albumin-hyaluronic acid hydrogel after seven days to evaluate the injectable volume and hydrogel distribution using micro-CT.

Brief paragraph of major findings and why they are significant

The authors found that chABC and papain showed comparable biomechanical changes associated with disc degeneration. This includes increased spinal segment flexibility and instability, reduced disc height, and larger injectable hydrogel volumes compared with fresh and sham controls. These changes were partially restored after hydrogel injection in both enzyme-treated groups.

Despite their similar biomechanical properties, the two enzyme groups produced unique tissue morphologies. Papain created a distinctive cavity within the nucleus pulposus, whereas chABC-treated discs remained macroscopically intact. These structural differences affected hydrogel distribution. chABC produced a diffuse, bubble-like pattern and papain generated a localized spherical deposit. Importantly, hydrogel distribution in chABC treatment more closely resembled discography findings in degenerated human discs.

The authors highlight that chABC and papain should not be considered interchangeable IVDD models. Although both induced similar biomechanical changes, they differed fundamentally in their macroscopic appearance. Consequently, chABC may be better suited to mimicking progressive degeneration, whereas papain better resembles a nucleotomy-defect model. These findings are particularly valuable for spine researchers developing biomaterials and emphasize the importance of selecting a degeneration model that reflects the clinical application. Appropriate model selection will enhance the translational relevance of future IVDD therapies.