Human platelet antigen systems in allogeneic peripheral blood progenitor cell transplantation: effect of human platelet antigen mismatch on platelet engraftment and graft-versus-host disease.
BACKGROUND
Alloimmune incompatibility in allo-geneic stem cell transplantation (ASCT), pregnancy, and blood transfusion might trigger an immune response with clinical consequences. Human PLT antigens (HPAs), which play a significant role in pregnancy or blood transfusion-associated alloimmune thrombocytopenia, are also expressed on the surface of tissues affected by GVHD. Thus, HPA mismatch in HLA-identical ASCT could play a potential role in PLT engraftment and GVHD.


METHODS
We studied the HPA-1, -2, and -5 genotypes in Caucasian donors and patients involved in 77 HLA-identical ASCTs. We evaluated the association of HPA compatibility with clinical outcome, analyzing the relevance of host-versus-donor HPA incompatibility in PLT engraftment and donor-versus-host HPA incompatibility in GVHD.


RESULTS
PLT engraftment and transfusion require-ments were similar in HPA-compatible and HPA-incompatible ASCT. Cases with severe thrombocytopenia or significant delayed PLT engraftment did not display host-versus-donor HPA incompatibility. Moreover, the incidence of GVHD did not correlate with HPA compatibility.


CONCLUSIONS
Our results support no role for these antigens in immune complications of ASCT: PLT engraftment, requirement of PLT transfusions, and GVHD.
García-Malo
M D
MD
University of Murcia, Department of Medicine, Murcia, Spain.
Corral
J
J
González
M
M
Solano
C
C
González-Conejero
R
R
Caballero
M D
MD
Pérez
R
R
Moraleda
J M
JM
Vicente
V
V
D000293:Adolescent; D000328:Adult; D000368:Aged; D016824:Antigens, Human Platelet / Q000032:analysis / Q000276:immunology*; D005260:Female; D006086:Graft vs Host Disease / Q000209:etiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D036102:Peripheral Blood Stem Cell Transplantation / Q000009:adverse effects*; D017713:Platelet Transfusion; D014184:Transplantation, Homologous
D016824:Antigens, Human Platelet