Product Names Platelet products include those derived from whole blood and those collected by apheresis. While the FDA has a nomenclature specific to each method of collection, many terms are in common use. This creates confusion in published papers and…
Product Names Plasma products in the United States include fresh frozen plasma (FFP), plasma frozen within 24 hours after phlebotomy (PF24 or FP24), plasma frozen within 24 hours after phlebotomy held at room temperature up to 24 hours after phlebotomy…
The majority of RBC products are made from 450 to 500 mL of whole blood donated into an anticoagulant–preservative solution; about 14% of RBC products are collected via automated RBC apheresis. Whole blood is centrifuged to pack the RBCs, the…
HLA (human leukocyte antigen) is the human major histocompatibility complex (MHC), a multigene family involved in the defense of humans (and all vertebrae) against pathogens. The HLA molecule’s role is to present peptides to T cells. Depending on the peptide,…
Platelet-specific antigens associated with the formation of alloantibodies in exposed patients are the basis for human platelet antigen (HPA) categorization. Over the years, these antigenic determinants have been mapped to a relatively short list of platelet-expressed adhesion/aggregation molecules, namely GPIa,…
Blood group systems not described in other chapters are discussed here, as well as antigens that have not yet been assigned to a blood group system. The International Society of Blood Transfusion (ISBT) classifies RBC antigens and also denotes them…
Lewis Blood Group System Le a and Le b antigens are synthesized by two independent fucosyltransferases, and Le a is a precursor molecule for synthesis of Le b ( Fig. 29.1 ). Antigens and Genetic Basis Lewis antigens (Le a…
MNS Blood Group System MNS blood group system contains 49 recognized antigens; the major antigens are M, N, S, s, and U. M and N antigens are located on glycophorin A (GPA), while S, s, and U antigens are carried…
Kell and Kx Blood Group Systems The Kell blood group system contains more than 34 antigens, although only one (K1) is of importance in routine practice. K1 is also commonly referred to as K, or incorrectly as “Kell,” as Kell…
The Rh blood group system (C, c, E, e, D, and more than 50 other antigens) is second only to ABO in clinical importance because the Rh antigens, especially D, are highly immunogenic and the antibodies can result in delayed…