Tiny chips, big potential: Modeling infections without animal testing

Prof. Dr Alexander Mosig conducts research into organ-on-chip systems as test models in infection and inflammation research. Photo: Szabó/UKJ
Prof. Dr Alexander Mosig conducts research into organ-on-chip systems as test models in infection and inflammation research. Photo: Szabó/UKJ

It doesn’t look like an organ at first glance: a small chip, hardly larger than a microscope slide, containing tiny chambers, reservoirs, and fine channels. Inside these chambers, human intestinal, lung, or liver cells grow – even immune cells can be part of the system. Through the miniature channels, fluids circulate just like blood in the human body. In this way, living mini-models of human organs are created in the laboratory.

“With our biochips, we can replicate infections and the associated inflammatory and immune processes under controlled conditions,” explains Prof. Dr. Alexander Mosig. The 49-year-old biochemist and molecular biologist has recently been appointed Professor for Alternative Methods to Animal Testing in Infection and Inflammation Research at Jena University Hospital.

This emerging research field pursues a clear goal: to replace animal testing wherever possible – while at the same time creating more precise human-based models. “Many scientific questions are still being studied in animal models because suitable alternatives are lacking,” says Mosig. “But in the interest of patients, we aim to recreate human disease processes in the lab as realistically as possible. Only then can we better understand disease mechanisms and predict individual drug responses.”

In his organ-on-chip models, Mosig and his team investigate molecular processes in lung and intestinal infections caused by viruses, bacteria, or fungi. He is particularly interested in how microorganisms interact with the human body and how the microbiome influences immune responses during infection and inflammation. The microfluidic chip systems developed by his group are now patented. Dynamic42, a Jena-based startup emerging from his research group, makes this technology available to academia and industry as a standardized platform.

After studying biochemistry in Jena, Mosig earned his PhD on immune processes in atherosclerosis and led several research projects at the Center for Sepsis Control and Care at Jena University Hospital. His innovative work on chip models has earned him multiple awards, including the Thuringian Research Award and the Federal Animal Protection Research Award. Mosig declined a professorship offer from University Medical Center Hamburg-Eppendorf in favor of the position in Jena. He is also involved in undergraduate biochemistry teaching and the research-oriented track of the Jena medical curriculum.

Looking ahead, Mosig aims to further strengthen 3R research at Jena University Hospital – Replace, Reduce, Refine – striving to minimize animal use and suffering in biomedical research. “We want to support researchers in Jena in adopting modern alternatives such as stem-cell-based systems and organ-on-chip technologies in their work,” Mosig explains. “To this end, we will offer workshops and training sessions and collaborate with colleagues to tailor these models to specific research needs.”

As of January 1, 2026, Alexander Mosig will also join the Cluster of Excellence "Balance of the Microverse" as a Principal Investigator. He will contribute his expertise in organ-on-chip technologies and host–microbiota–immune interactions to the Cluster’s interdisciplinary research areas, further bridging fundamental microbiome science with translational infection research.