ARTIFICIAL BLOOD SUBSTITUTES – Update on the Promise of a Medical Breakthrough –
Published in Blood Substitutes.
Blood substitutes — also called oxygen therapeutics or hemoglobin-based oxygen carriers (HBOCs) — offer the promise of new and important life-saving medical treatments.
Blood is a vital, life-sustaining fluid that picks up oxygen in the lungs and then carries it to the heart and the rest of the body. Blood performs many functions such as transporting nutrients from the digestive system, removing toxins and waste, and fighting germs.
Blood is composed of a watery substance called plasma as well as three different types of cells or parts of cells that float in the plasma. The formed elements are red blood cells (RBCs), white blood cells (WBCs), and platelets.
White blood cells are part of the body’s immune system that destroys viruses and bacteria, the pathogens that cause infections. Platelets form clots to prevent bleeding from cuts and small wounds. RBCs account for more than 90% of the formed elements in the blood.
These abundant cells transport oxygen and carbon dioxide via blood vessels called arteries and veins. RBCs are disc-shaped with a large surface area for absorbing and releasing oxygen.
These cells do not have a nucleus in the center, but instead contain a complex molecule — hemoglobin (Hb) — that collects and releases oxygen.