RT Book, Section
A1 Coppage, Myra
A1 Stroncek, David
A1 McFarland, Janice
A1 Blumberg, Neil
A2 Kaushansky, Kenneth
A2 Lichtman, Marshall A.
A2 Prchal, Josef T.
A2 Levi, Marcel M.
A2 Press, Oliver W.
A2 Burns, Linda J.
A2 Caligiuri, Michael
SR Print(0)
ID 1121105801
T1 Human Leukocyte and Platelet Antigens
T2 Williams Hematology, 9e
YR 2015
FD 2015
PB McGraw-Hill Education
PP New York, NY
SN 9780071833004
LK hemonc.mhmedical.com/content.aspx?aid=1121105801
RD 2024/04/19
AB SUMMARYThe  human  leukocyte  antigens  (HLAs)  are  highly  polymorphic  glycoproteins  encoded  by  the  major  histocompatibility  complex  on  chromosome  6.  Their  biologic  function  is  presentation  of  antigenic  peptides  to  T  lymphocytes,  and  there  are  two  major  classes:  class  I  (A,  B,  and  C  loci)  and  class  II  (DR,  DQ,  and  DP  loci).  Class  I  antigens  are  present  on  almost  all  nucleated  cells,  whereas  class  II  antigens  are  primarily  expressed  on  B  cells  and  other  antigen-presenting  cells  such  as  dendritic  cells,  endothelial  cells,  and  monocytes.  These  antigens  play  key  roles  in  hematopoietic  cell  transplantation  acceptance/rejection  and  allosensitization  to  nonleukoreduced  blood  transfusions  leading  to  platelet  transfusion  refractoriness,  with  lesser,  but  distinct  roles  in  solid-organ  transplantation.  Other  clinically  important  lineage-specific  white  cell  antigens  include  those  on  neutrophils,  which  are  much  less  polymorphic  and  less  commonly  a  cause  of  clinical  problems  than  the  HLA  system.  Antibody  to  neutrophil  antigens  plays  a  role  in  autoimmune  neutropenia,  and  reactions  such  as  transfusion-related  acute  lung  injury.  Platelets  also  possess  a  relatively  limited  number  of  polymorphic  antigens  that  are  involved  in  clinical  problems  such  as  posttransfusion  purpura  and  platelet  transfusion  refractoriness,  and  neonatal  problems  such  as  alloimmune  thrombocytopenia.