Symcel’s Chronic Wound Biofilm Model — For Clinically Relevant Testing

By Dr. Kasper Kragh

we can't begin to develop better antimicrobials if we can't test them in clinically relevant models

At Symcel, we’ve developed a new chronic wound model with one central question in mind: 
Are we truly replicating the real environment of chronic wounds when we test treatments in the lab? 

Too often, the default in vitro methods rely on planktonic cultures, rich media, or static agar surfaces. While these systems are easy to use, they don’t reflect the complex, heterogeneous microenvironment of an actual chronic wound. 

The microenvironment matters in chronic wound infections

In chronic wounds, bacteria are not swimming in nutrient-rich liquids or spreading across uniform surfaces. Instead, they exist in dense biofilm aggregates, often metabolically inactive, embedded in tissue, and subject to host immune responses, low oxygen levels, and nutrient limitations. 

The phenotypic state of a bacterial cell is highly dependent on its surrounding environment — just as an elephant’s behavior would change if dropped into the Arctic, a bacterial cell behaves fundamentally differently in a wound than it does in LB broth. Understanding this is critical. 

lab models need to reflect the complexity of the chronic wound

That’s why we’ve partnered with SynthBiome to use their clinically-inspired chronic wound media, developed through their innovative RNA-seq profiling of bacteria in real wounds. This media encourages pathogens to adopt physiologically relevant states — forming small, often-invisible biofilm aggregates that better mimic their behavior in chronic infections. 

Using this media, we pre-grow bacteria directly inside Symcel’s calVial inserts over 24 hours — enabling in situ formation of wound-like biofilms. These aggregates are: 
- Reproducible, yet reflective of in vivo complexity 
- Formed in clinically relevant conditions 
- Suitable for testing across a wide range of wound care pathogens 

With this system, up to 32 parallel chronic wound biofilm models can be run simultaneously. 

monitoring chronic wound models in the calscreener allows real-time monitoring of biofilms

Leveraging isothermal microcalorimetry, the calScreener allows us to track the metabolic activity of the biofilms in real time — without disturbing the biofilm or removing bacteria from the system. 

This enables us to: 
- Detect surviving subpopulations deep within biofilms 
- Monitor treatment kinetics and mode of action over time 
- Analyze treatments without relying solely on regrowth or plating 
- Explore combination therapies or polymicrobial infections under wound-like conditions 

Unlike traditional readouts that reduce results to “what grows on an agar plate,” our approach offers continuous, sensitive, and non-invasive monitoring — giving a more nuanced picture of what happens inside the wound model as treatment progresses. 

bridging the gap between chronic wounds and the lab bench

This chronic wound model marks a step toward bridging the gap between in vitro testing and in vivo performance. It enables researchers to study biofilm behavior and treatment response in a controlled yet physiologically relevant context, with minimal hands-on time and high reproducibility. 

We believe this is a powerful tool for researchers, clinicians, and developers working to advance the next generation of chronic wound therapies. 

If we want better treatments for patients, it starts with better models. 

Download our Application Note on our wound model HERE