ABSTRACT
Pretransplantation crossmatching is an integral part of kidney transplantation. Flow cytometric crossmatch (FCXM) is more sensitive than complement-dependent cytotoxic crossmatch (CDC-XM). However, the clinical significance of positive FCXM with negative CDC-XM is controversial. We evaluated FCXM in 455 consecutive deceased donor renal transplants. All had a negative CDC-XM. There were 341 T-cell and B-cell FCXM negative and 38 T-cell and B-cell positive. There was a higher percentage of retransplantations and HLA mismatches (26.3% vs 8.2%, P= .002 and 2.45 vs 1.99, P= .02, respectively) in the FCXM-positive group compared with the FCXM-negative group; 65.8% of the FCXM-positive patients had rejection compared with 49.3% of the FCXM-negative patients (odds ratio [OR]=1.89, P= .06). FCXM-positive patients had a higher incidence of vascular rejection (28.9% vs 12.6%, OR=2.68, P= .008). One- and 5-year graft survivals were 84% and 66% in the FCXM-positive group vs 90% and 75% in the FCXM-negative group. Censoring for patient death, 1- and 5-year graft survivals were 84% and 73% in the FCXM-positive group vs 94% and 82% in the FCXM-negative group. There was no difference in renal function between the 2 groups. In conclusion, a positive T-cell and B-cell FCXM transplant with a negative CDC-XM is associated with a higher incidence of rejection, twice the risk of vascular rejection, and a trend toward poorer graft survival.
Subject(s)
Histocompatibility Testing/methods , Kidney Transplantation/immunology , Tissue Donors , Adolescent , Adult , Aged , Aged, 80 and over , Cadaver , Child , Child, Preschool , Drug Therapy, Combination , Female , Flow Cytometry/methods , HLA Antigens/immunology , Humans , Immunoglobulins/immunology , Immunosuppression Therapy/methods , Immunosuppressive Agents/therapeutic use , Lymphocytes/immunology , Male , Middle Aged , Reoperation/statistics & numerical data , Sensitivity and Specificity , Treatment OutcomeABSTRACT
We designed a set of 35 polymerase chain reaction sequence-specific primers (PCR-SSP) in 29 SSP mixtures to assign 29 HLA-B*27 4-digit level alleles (B*2701-B*2721 and B*2723-B*2730). This was used in conjunction with our 41 PCR-SSP primer mixture low-resolution HLA-B typing set to fully differentiate B*27 from all other HLA-B alleles. Successful typing set validation used 521 B*27 samples covering 13 (B*2701-B*2710 and B*2712, B*2717, B*2723) alleles. The distribution of B*27 alleles was determined in a random population of 4020 local blood donors and the use of PCR-SSP B*27 typing in our routine flow cytometry-based HLA-B27/B2708 typing strategy is described.
Subject(s)
DNA Primers , DNA Probes, HLA , HLA-B27 Antigen/genetics , Polymerase Chain Reaction/methods , Alleles , Flow Cytometry , Genetic Carrier Screening/methods , Genotype , Humans , Sensitivity and SpecificityABSTRACT
We evaluated the HLA-B27 typing reagent Com-B27, which is claimed to show minimal cross-reactivity with HLA-B7, for use in flow cytometry-based typing. This combination reagent consists of the fluorescein-conjugated HLA-B27 mouse monoclonal antibody ABC-m3 and a non-conjugated HLA-B7 monoclonal antibody that is claimed to block the reactivity of ABC-m3 to B7 without affecting its reactivity to B27. It reacted well with B27 (B*2702, B*2705) and B2708 [mean median channel fluorescence intensity (MCFI) 8.40] and weakly with B7 (including cells from homozygous B*07 donors), B42/B73 and B22/B37/B44 reference cells (mean MCFI 2.05, 3.09 and 1.10, respectively). It showed a uniform discrimination between B7 and B27/B2708 with no 'overlap' in MCFI values, which was seen with the standard ABC-m3 antibody. There was complete agreement when our standard three-antibody-based B27/B2708 flow cytometry assay and the Com-B27 reagent alone were used to independently assign B27/B2708 status to 651 random patients. Thus, the Com-B27 reagent provided improved discrimination between B7 and B27/B2708 over the ABC-m3 antibody, and its B27/B2708 assignments were comparable with our standard flow cytometry assay. However, for consistently reliable B27/B2708 typing we continue to recommend the use of a minimum of two B27 reagents in a protocol that includes DNA-based testing of 'equivocal' B27/B2708 assignments.
Subject(s)
Antibodies/immunology , Fluorescein , HLA-B27 Antigen/analysis , Staining and Labeling , Animals , HLA-B27 Antigen/immunology , Humans , MiceABSTRACT
Severe or life-threatening anaphylactic reactions during blood transfusion to patients with anti-IgA, though infrequent, can be avoided by transfusing blood products prepared from IgA deficient donors. This report describes the development and use a passive haemagglutination assay adapted for use on the Olympus PK7100 blood group analyser. Donor plasma samples identified as being presumptive IgA deficient were further screened by a manual passive haemagglutination inhibition technique and finally confirmed by means of a quantitative enzyme-linked immunosorbent assay. Of 5723 donors tested simultaneously for IgA deficiency, blood grouping and red cell antibody screening, six (1 in 954) were confirmed as IgA deficient (i.e. < 100 ng/ml of IgA). The test is simple and cost effective and can be used to establish a database of IgA-deficient donors.
