Scarlet gets $14M for smart red blood cells

Why it matters: The project pushes Scarlet’s technology beyond using engineered red blood cells as passive carriers of therapeutic proteins. The aim is to equip them with biological circuits capable of sensing a signal, making a decision and switching a response on or off.

• The majority of Scarlet’s work will focus on cells that respond to physiological conditions by activating systems that remove toxic metabolites from the bloodstream, CEO Alistair Irvine told European Biotechnology. One stimulus being investigated is hypoxia, or low oxygen.
• “This contract is focussed on generating red blood cells that can sense-decide-act in response to physiological stimuli such as hypoxia,” Irvine said. The approach is directly relevant to Scarlet’s existing therapeutic work, which includes removing ammonia or oxalate from the circulation of patients with hyperammonemia or hyperoxaluria.

Zoom in: Scarlet will coordinate the project with the University of Bristol, where its technology originated; Northwestern University (USA), which brings sensing and synthetic biology expertise; and UK cell-manufacturing company Unicorn Biotechnologies.

• A successful project would initially mean “a laboratory proof-of-concept showing that the engineered red blood cells can retain functional biological components that sense a defined physiological signal and produce an appropriately controlled response, while still maintaining the fundamental properties expected of a red blood cell,” according to Irvine.

The big picture: DARPA’s ambitions for the Smart-RBC (red blood cells) program extend beyond conventional therapeutics. The US defense agency says the program is designed to “enhance physiological resilience” and temporarily improve the natural capabilities of military personnel operating in extreme environments. Its own program materials describe the objective as optimizing warfighter physiology using red blood cells equipped with “sense, decide, and act” circuits.

• That leaves the technology with an obvious dual-use dimension. Asked whether the approach could eventually be used to improve tolerance to stresses such as hypoxia, heat or fatigue in healthy people, Irvine acknowledged that “the potential applications are broad,” but said Scarlet remains focused on developing treatments for patients.

What’s next: There is no blanket restriction preventing technology developed through the project from being used for other applications. Scarlet and its partners retain commercial rights, Irvine said, while IP generated during the project will belong to Scarlet and/or its consortium partners. Details of the US government’s associated rights are confidential.

• For Scarlet, the project is also practical: Irvine said “most of, if not all” of the technology and learnings should transfer into its therapeutic programs and accelerate their development.