The number of amino acid triplet differences between patient and donor is predictive for the antibody reactivity against mismatched human leukocyte antigens.
BACKGROUND
The correlation between antibody production against mismatched donor human leukocyte antigens (HLA) and the number of amino acid sequence mismatches was analyzed in patients who rejected a kidney transplant (n=146).


METHODS
A similar analysis was performed for the antibody production of women against the paternal HLA antigens of their child (n=1,397). The amino acid sequence (triplet) differences were analyzed using the HLAMatchmaker algorithm.


RESULTS
In both groups, a positive correlation was found between the number of triplet mismatches and the percentage of individuals producing antibodies (P <0.0001). If zero triplet mismatches were present, no antibodies were formed in all cases. When 11 or 12 triplet mismatches were present, 94% of the transplant patients produced antibodies against the donor. In pregnancy, 11 or 12 triplet mismatches led to 27% of the women producing specific antibodies.


CONCLUSIONS
These results indicate that the immunogenicity of the fetus is lower than that of a rejected kidney and that analysis of the number of triplet mismatches can predict the antibody reactivity against the mismatched HLA antigens.
Dankers
Marlies K A
MK
Department of Immunohematology and Blood Transfusion, Leiden University Medical Center, Leiden, The Netherlands. m.k.a.dankers@lumc.nl
Witvliet
Marian D
MD
Roelen
Dave L
DL
de Lange
Peter
P
Korfage
Nelleke
N
Persijn
Guido G
GG
Duquesnoy
René
R
Doxiadis
Ilias I N
II
Claas
Frans H J
FH
D000595:Amino Acid Sequence; D005260:Female; D006084:Graft Rejection / Q000235:genetics / Q000276:immunology; D006680:HLA Antigens / Q000235:genetics*; D006650:Histocompatibility Testing; D006801:Humans; D007518:Isoantibodies / Q000096:biosynthesis*; D016030:Kidney Transplantation / Q000009:adverse effects / Q000276:immunology*; D008297:Male; D008431:Maternal-Fetal Exchange / Q000235:genetics / Q000276:immunology; D011247:Pregnancy; D014019:Tissue Donors
D006680:HLA Antigens; D007518:Isoantibodies