Eurotransplant Reference Laboratory
Information about Donor Frequency Calculator Heart
Virtual PRA Calculator.
Virtual PRA Calculator is an application to be used by professionals working in HLA Laboratories and other HLA specialists to define the percentage virtual Panel Reactive Antibodies (vPRA) within the Eurotransplant donor population.
The virtual PRA is calculated on basis of unacceptable antigens only. These antigens are defined by HLA antibody analysis from screenings for HLA specific, transplantation relevant antibodies. The calculation is performed for unacceptable antigens on HLA-A, -B, -C, -DRB1, -DRB3/4/5, -DQB1, -DQA1, DPB1, and -DPA1. Unacceptable antigens can be entered on the allelic, split, or broad antigen level. For HLA alleles, the official WHO nomenclature must be used, whereas for split or broad antigen level, Eurotransplant match determinants must be used. Entering a broad antigen as unacceptable results in all underlying split antigens and alleles being unacceptable.

Description of the underlying database.
Calculations are performed on the ETRL reference database v4.0, which contains HLA data of 10.000 individuals from within the Eurotransplant area, obtained from genotype frequencies provided by the DKMS.
Full 11-locus genotype frequencies with alleles at p-group level of registered stem cell donors were used from all eight Eurotransplant countries. HLA types for 11 loci on second field level were constructed on a country-specific basis in equal numbers to the ETRL reference database v3.0. Bw4/Bw6 were assigned based on HLA-B antigens only. Please be aware that assigning a Bw4 will not include corresponding HLA-A antigens. HLA-A antigens harboring a Bw4 epitope need to be filled in separately. DR53 has been removed for individuals with DR7 and DQ9, because in this case DR53 is non-expressed.
The original distribution of blood groups for a specific country in ETRL reference database 3.0 was randomized and assigned to individuals of panel 4.0 of the same country.
For any suggestion or remarks, please contact: