TCF GmbH is developing a recombinant version of the HIV envelope protein that, when used on its own, can function as a therapeutic to reestablish immune tolerance in autoimmune diseases. Preclinical studies showed the therapeutic can prevent graft-versus-host disease without compromising the immune system.

TCF founder and CEO Olaf Althaus noted the human immune system has a delicate balance between effector T cells, which stimulate immune reactions, and regulatory T cells (Tregs), which suppress T cell-mediated responses and maintain immune tolerance.