#transfusion

• ABO system — The major human blood group classification system (A, B, AB, and O), genetically determined by the presence or absence of specific antigens (agglutinogens) on the surface of red blood cells and antibodies (agglutinins) in the plasma. In modern medical lexicon, it functions as an invariable proper noun used to identify transfusion compatibility.
• Agglutinogen — An antigen substance, protein or carbohydrate in nature, located on the outer surface of the erythrocyte membrane, bacteria, or other biological cells. Its structural interaction with a specific agglutinin in the plasma triggers the agglutination reaction, serving as the core biochemical element that defines blood types within the ABO and Rh systems.
• Autologous — Originating from the same individual; obtained, harvested, or derived from the patient's own organism to whom it is to be administered. In surgical and hematological practice, the term describes own tissue grafts, stem cells, plasma, or blood transfusions, this medical approach completely eliminating the risk of immune rejection, graft-versus-host disease, or transmission of viral infections.
• Autotransfusion — A hematological medical procedure consisting of transfusing a patient with their own blood, previously collected via scheduled autologous donation or salvaged and filtered intraoperatively during major surgical interventions. This structural technique completely eliminates the risks of immune rejection, transmission of infectious diseases, or incompatible post-transfusion reactions.