Synthetic blood

Synthetic blood is meant to replicate the essential functions of natural blood, including oxygen transport, immune response, coagulation, and metabolic support. Blood comprises cellular components—red blood cells, white blood cells, and platelets—and a plasma matrix that carries nutrients, signaling factors, and metabolic intermediates. Current efforts primarily address individual components, with companies like Hemarina and KaloCyte focusing on specific challenges such as oxygen transport and clotting, but no system replicates the complete functionality of blood.

Red blood cells transport oxygen via hemoglobin, and synthetic substitutes aim to mimic this function. Hemoglobin-based oxygen carriers (HBOCs) and perfluorocarbon emulsions have been developed to deliver oxygen in clinical scenarios like trauma and surgery. For example, Hemarina’s oxygen carrier HemO2 utilizes hemoglobin from marine worms. However, these products face issues such as oxidative stress and limited stability in circulation, which reduce their efficacy for prolonged use.

White blood cells are central to immune surveillance, inflammation control, and tissue repair. Research into synthetic substitutes for immune cells includes nanoparticle-based systems and engineered cell-free receptors designed to neutralize pathogens or modulate immune responses. These approaches remain experimental and far from clinical or commercial viability. An alternative would be natural immune cells grown in bioreactors, but this also is a nascent area of research.

Platelets are key for coagulation, adhering to damaged blood vessels and aggregating to form clots. Artificial platelets, such as those developed by Haima Therapeutics, utilize lipid or polymer platforms to emulate these properties. These products are under investigation for use in trauma and surgery, where rapid hemostasis is critical. Although they mimic certain platelet functions, integration with the full clotting cascade is limited, and their long-term use is not yet feasible.

Plasma is a complex mixture of proteins, metabolites, and signaling molecules required for metabolic balance and inter-organ communication. Volume expanders such as saline or albumin solutions provide basic plasma replacement, but these lack the bioactive factors necessary for systemic support. Synthesizing functional plasma has proven challenging because the specific requirements of each organ, such as liver-derived coagulation factors or kidney-modulating hormones, are incompletely understood. Current synthetic plasma products address only narrow aspects of its functionality, limiting their application in prolonged or systemic scenarios.

While companies like Hemarina and Haima Therapeutics address niche components of synthetic blood, the development of a complete, integrated system will require advances in biomolecular synthesis, bioreactor technology, and recombinant methods.