Human veins from the bioreactor

The Swiss Technology Innovation Centre CSEM and the start-up ClexBio, registered under Nordovo Biosciences AS and specialising in regenerative medicine, have developed a new type of bioreactor in which human veins can be grown in the laboratory. The solution, funded by the Research Council of Norway, aims to improve the lives of millions of people suffering from severe chronic venous insufficiency (CVI) by offering them the possibility of implanting bioengineered veins.

With CVI, the valves in the leg veins do not function properly, the blood flows backwards and accumulates in the veins. This disease, which affects millions of people around the world, can cause symptoms such as varicose veins, pain, swelling, oedema, cramps and recurrent ulcers. Synthetic implants or stents have so far failed because they lead to thrombotic events in the venous system. Current treatment options are limited to compression stockings and symptomatic wound treatment.

Biodegradable matrix for the production of human tissue

Together, the partners have developed and tested a bioreactor prototype for the production of functional vein implants from human stem cell tissue. The Norwegians contributed their expertise in the field of regenerative medicine, the company's own IP platform and their knowledge of hydrogels. The Swiss contributed engineering expertise in the fields of automation, microphysiological systems and intelligent laboratory technology.

ClexBio's VivoSet platform technology can be used to create complex tissue such as veins. Normal cells are combined with ClexBio's patented biomaterial in a microfluidic process. As soon as the desired tissue has formed, both the cells and the scaffold are removed. What remains is an implant consisting of human extracellular matrix, the main component of natural tissue. The vein graft cultivated in this way can be implanted directly into patients.

The aim of the Supervene project was to develop standardised, automated manufacturing processes for regenerative medicine that can be transferred from the laboratory to the clinical setting. „VivoSet is a new technology that can unleash the incredible potential of novel cell therapies“, says Stéphanie Boder-Pasche, Senior Project Manager in Cell Microtechnologies at CSEM. Her colleague Gilles Weder, Head of Research & BD in Life Science Technologies at CSEM, adds: „For the production of such revolutionary implants, we need a closed high-tech bio-production system that works automatically.“

Closed-loop production system

The veins mature over several weeks in a sterile environment, automatically surrounded by media for oxygen and nutrient supply. For Armend Håti, CEO and co-founder of ClexBio, this is an important milestone: „Using a closed system to produce the vein grafts reduces the risk of contamination, ensures product quality and safety and facilitates regulatory compliance. This is an important prerequisite for us to be able to conduct human studies in the future and market the product on a large scale under GMP conditions.

The first preclinical results from ClexBio show that the implants do not trigger an immune response in patients after implantation. Instead, they are colonised by the patient's own cells and transform into functional tissue that integrates into the body and grows with it - a truly regenerative solution and a potential breakthrough in modern medicine.

Following the basic development of the system, ClexBio will now conduct further pre-clinical testing in larger animal models to gather data on the functional capacity of the bioengineered vein implants in the cardiovascular system, including their ability to colonise with the host's own cells. „We are excited about the paradigm shift this can introduce for human surgery and for the treatment of damaged tissue – we are taking a big step beyond the world of synthetic implants into the world of bioengineering“, says Armend Håti.

Article from "transkript" dated 23 February 2024