Don't get squeamish… It's only about blood…typing!
Karl Landsteiner (1868-1943) was a Vienna physician awarded the Nobel Prize for Medicine in 1930 for his work in typing blood. Landsteiner reported in 1875 a man’s transfusion of blood to other animals allowed blood corpuscles to clump and break up, causing disastrous results. He reasoned the same misfortune would happen if blood between humans were transfused. Not satisfied with this result, he continued his research.
In 1909, Landsteiner classified the human blood into Types, known as A, B, AB and O. He observed two distinct chemical molecules present on the surface of the red blood cell. He labeled one Type A. If only the "B" molecule was present, it was Type B. If both were present, it was Type AB. If neither molecule was present, the blood was Type O.
He discovered if two different blood types are mixed together, the blood cells might begin to clump in the blood vessels, causing a potentially fatal situation. Therefore, it is important that blood be typed before transfusions take place.
A person with Type A blood can donate blood to a person with Type A or AB. A person with Type B blood can donate to a person with Type B or AB, and a person with AB blood can donate to a person with type AB only. A person with Type O blood can donate to anyone.
A person with Type A blood can receive blood from a Type A or O. A Type B can receive from a Type B or O. A person with Type AB can receive from anyone, and a Type O can receive only from another Type O. Because of these patterns, a person with Type O blood is said to be a universal donor, and a person with AB blood is a universal receiver. In general, it is still best to received blood from a donor of the same type.
Another important blood type is described in the Rh system. The Rh system is far more complex than the ABO system. Using research done on Rhesus monkeys, it was found that certain proteins were present in not only monkey’s blood, but also in some human blood, The presence of this protein or the lack of it, is referred to as the Rh (Rhesus) factor. If a person’s blood does contain the protein, the blood is said to be Rh positive. Conversely, if the protein is not present, the blood is considered Rh negative.
The Rh factor is connected with blood type. For example, blood can be AB+, which means it is AB type blood with a positive RH factor. Or it may be O- blood which means type O blood with a negative Rh factor. The Rh factor is particularly important to expectant mothers. On occasion, a baby will inherit an Rh positive blood type from its father, while the mother has Rh negative blood. The baby’s life could be in danger if the mother’s negative blood starts attacking the baby’s positive blood. If this happens, usually the baby’s blood is exchanged by transfusion for new blood that matches the mother.
Not only does blood have types and factors, it also contains many components. Whole blood contains red blood cells, white blood cells and platelets suspended in a fluid called plasma. Each of these components has a specific job.
Red blood cells are prepared from whole blood by removing the plasma. People who benefit from transfusions of red blood cells include those with chronic anemia and acute blood loss, due to trauma or surgery. Plasma contains red and white blood cells and platelets, along with albumin, fibrinogen, globulins and other clotting proteins. Plasma supplies vital minerals, such as potassium and sodium. It is usually not used for transfusion but is separated into specific products for use in medical treatments.
Plasma contains many proteins that are obtained by a process called fractionation. This process was developed during WW ll ,and the proteins are either heat-treated and/or solvent detergent- treated to kill certain viruses including HIV and hepatitis B and C. Plasma derivatives include: Factor Vlll Concentrate, Factor1X concentrate, Anti-inhibitor Coagulation Complex (AICC), Albumin, Immune Globulins, including Rh Immune Globulin, Anti-Thrombin lll Concentrate and Alpha 1-Proteinase Inhibitor Concentrate.
Plasma also contains cryo-precipitated AHF, a protein rich in certain clotting factors. When separated from plasma, it is used most often for treating hemophilia and von Willebrand’s disease, an inherited blood coagulation abnormality.
Platelets are very small cellular components of the blood that help the clotting process. They are made in the bone marrow, and are vital to life. Platelets help prevent massive blood loss resulting from trauma, as well as blood vessel leakage. Platelets may be obtained by centrifuging blood or by a process known as aphaeresis.
White blood cells protect the body from invasion of bacteria, fungi and viruses. White cells can be harvested by centrifuge or aphaeresis, and are used to treat infections that do not respond to antibiotics. The effectiveness of white blood cell transfusion is still being investigated.
Source: www.aabb.org
Editor’s Note: This article was written by Dottie Cobb. Her husband, Dave, is a frequent Red Cross blood donor. Both are Ingham volunteers. Blood used in hospitals and other lifesaving situations is always in short supply. Every 56 days you can donate a pint of blood. Call The American Red Cross to schedule a donor appointment: (517) 484-7461. Find about whether you can be a donor by going to the website: www.redcross.org
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