Blood has two main components: serum and cells. In 1900 Karl Landsteiner, a physician at the University of Vienna, Austria, noted that the sera of some individuals caused the red cells of others to agglutinate. This observation led to the discovery of...

The development of blood transfusion, a potentially life-saving technique, was hampered by a serious problem: many times the patient would suffer an often fatal "transfusion reaction," apparently to the donated blood itself. The cause of such reactions...

The development of blood transfusion, a potentially life-saving technique, was hampered by a serious problem: many times the patient would suffer an often fatal "transfusion reaction," apparently to the donated blood itself. The cause of such reactions...

Rh factor describes blood type compatibility issues involving Rh blood groups. These play a critical role in transfusions and in obstetrics. Rh blood groups were first discovered in 1940 by Karl Landsteiner and Alexander Wiener in their experiments...

Human red blood cells contain protein molecules (antigens) in their cell membranes that determine the blood type of an individual. There are several kinds of antigens present on human red blood cells, as well as the Rh antigen. People with the Rh...

Blood groups are inherited. Most familiar are the blood types of the A-B-O group and Rh types, but several others have been found that display the antigen-antibody reaction. In the seventeenth century, the idea of saving lives by transfusion was first...

Dealing with serious blood loss in an injured person has long been a difficult challenge for medical scientists. One solution has been to treat the patient with blood transfused from another person or an animal. In some instances, this approach worked...

Until 1900, no one understood why blood could not be transfused from one person to another without occasional difficulties. Viennese pathologist Karl Landsteiner was the first to discover that not everyone's blood is exactly alike, and actually can be...

Classification of blood by inherited antigens associated with erythrocytes (red blood cells). The ABO blood-group system and Rh blood-group system are among those most commonly considered. Without identification of these factors, blood transfusion from...

An immunologically distinct, genetically determined class of human erythrocyte antigens, identified as A, B, AB, and O. A classification of red blood cell surface antigens, ABO is the best known of the blood group...

A way of saying which blood group antigens are present on the person’s red...

A blood type (also called a blood group) is a classification of blood based on the presence or absence of inherited antigenic substances on the surface of red blood cells (RBCs). These antigens may be proteins, carbohydrates, glycoproteins or...