[Anti PLA or anti HPA-1 platelet allo-immunization].
The HPA-1 platelet antigenic system (PLA/Zw) is involved in most cases of antiplatelet alloimmunization. The two alleles HPA-1a and HPA-1b are likely to differ only at the amino acid position 33. This difference is probably due to a unique mutation at base pair position 196 on the glycoprotein IIIa gene which encoded this antigen. Anti HPA-1a alloimmunization is responsible for neonatal thrombocytopenia and post-transfusion purpura. Most immunized women belong to the HLA DR3, DRw52a phenotype, suggesting that this class II molecule may play a role in the presentation of HPA-1a peptide to specific helper T cells.
Muller
J Y
JY
Centre Régional de Transfusion Sanguine, Nantes.
D016824:Antigens, Human Platelet / Q000235:genetics / Q000276:immunology*; D005260:Female; D000949:Histocompatibility Antigens Class II / Q000235:genetics; D006801:Humans; D007231:Infant, Newborn; D010980:Platelet Membrane Glycoproteins / Q000737:chemistry / Q000235:genetics; D011696:Purpura, Thrombocytopenic / Q000209:etiology / Q000276:immunology; D013921:Thrombocytopenia / Q000276:immunology / Q000628:therapy; D065227:Transfusion Reaction
D016824:Antigens, Human Platelet; D000949:Histocompatibility Antigens Class II; D010980:Platelet Membrane Glycoproteins
L'allo-immunisation plaquettaire anti PLA ou anti HPA-1.