The body contains an average of nine to eleven pints of blood, depending on a person’s size and weight. Blood travels about 12,000 miles every day and provides cells with nutrients, transports hormones, and removes waste products. The body’s network of veins, arteries and capillaries is nearly 60,000 miles long.
Over 99% of the solid particles present in blood are red blood cells (erythrocytes) due to their red color. The rest are pale or colorless white blood cells (leukocytes) and platelets (thrombocytes). Blood is 55% blood plasma and about 45% different types of blood cells. Blood plasma is a light yellow liquid. Over 90% of blood plasma is water, while less than 10% is proteins, electrolytes, vitamins, and nutrients.
Red blood cells pick up inhaled oxygen and transport it from the lungs through the bloodstream to the cells of the body. Red blood cells have no nucleus, look like discs, and bend easily to squeeze through narrow blood vessels. Cells need oxygen for the metabolism to work, for the heart to beat and the brain to function. The red blood cells pick up carbon dioxide as a waste product and transport it back to the lungs to be exhaled.
White blood cells defend against invasion by lethal pathogens. Not all white blood cells are the same. Each type has a different function. Some fight intruders, such as bacteria, viruses, parasites, or fungi and render them harmless. Others produce antibodies, which target foreign objects or germs. Certain white blood cells can kill cancerous cells.
Platelets in plasma form clots that prevent fatal hemorrhages and promote wound healing. If a blood vessel is damaged, the healing process begins with blood platelets binding closely together on the inside of the damaged wall of the blood vessel, causing a plug to form that closes the wound. Blood platelets look like little discs, but they are much smaller than red blood cells.
All solid parts of blood originate from common parent cells, stem cells, produced mainly in the bone marrow. Bone marrow stem cells spawn every kind of blood cell. The various blood cells develop in several stages from stem cells to blood cells or blood platelets. When the blood cells are mature, they are released into the bloodstream.
Blood is constantly being renewed by stem cells in the bone marrow. Red cells turn over every few months. Most white cells and platelets replace every few days. When harvested and injected into an injured joint, stem cells can help to repair damaged cartilage, reduce inflammation and relieve pain. Platelet rich plasma is a natural healer and when centrifuged with growth factors and injected into the body may speed up the healing process.
Hematologists have studied the basic biology of stem cells for decades, exploring their extensive potential to repair damaged tissue, fight infections, and reduce autoimmune diseases. Stem cells and platelet rich plasma stimulate the body to heal itself with its own concentration of stem cells and plasma. The DOC orthopedic surgeons have successfully applied regenerative therapies to regenerate damaged tissues and promote healing. Plan to attend a DOC regenerative medicine seminar in the near future to learn more about regenerative therapies or make an appointment for a consultation with your DOC orthopedic surgeon.