OBJECTIVE: To retrospectively analyze the identification results of irregular antibodies, to clarify the distribution features and to explore the relation of alloantibodies and autoantibodies with the immunized history of patients and disease kinds. METHODS: 49 820 patients who applied for red blood transfusion during Sep 1st 2017 to Sep 1st 2018 were selected. All the specimens were screened for the antibody by microcolumn gel antiglobulin technique, which then were identified for irregular antibody. RESULTS: Antibodies were found in 861 (1.73%) of all 49 820 transfused samples. The alloimmunization history of the patients with antibodies was significantly different between male and female (χ=18.54，P＜0.01). The alloantibody was the most common, accounting for 59.50% in all of the antibodies. Warm autoantibody, anti-E, anti-M, anti-cE and anti-Ce accounted for 68.5% of the antibodies. The blood group of Rh, MNS and Lewis were responsible for 92.40% of alloantibody, especially anti-E accounted for the largest percentage(38.60%) of alloantibody. Patients with alloantiboies experienced much more the alloimmunization and transfusion history (χ=20.13，P＜0.01；χ=5.40，P＜0.05) . The distribution of auto and alloantibody was very significantly different among the ddifferent isease (χ=51.8，P＜0.01), Hematopathy, solid tumor and osteoarthropathy were often associated with alloantibody, otherwise, autoantibodies often occurred in hematopathy and autoimmune disease. CONCLUSION The most important factor that results in antibody-screening positive is alloantibody, in which anti-E antibody from Rh blood group system in most common.
Antibodies ; immunology ; Blood Group Antigens ; Blood Transfusion ; Erythrocytes ; Female ; Humans ; Isoantibodies ; Male ; Retrospective Studies

BACKGROUND: Although single antigen bead assays (SAB) are approved qualitative tests, the median fluorescence intensity (MFI) values obtained from SAB are frequently used in combination with quantitative significances for diagnostic purposes. To gauge the reproducibility of SAB results, we assessed the interlaboratory variability of MFI values using identical kits with reagents from the same lot and the manufacturer's protocol. METHODS: Six serum samples containing HLA-specific antibodies were analyzed at five laboratories by using Lifecodes LSA Class I and Class II SAB kits (Immucor, USA) from the same lot, according to the manufacturer's protocol. We analyzed the concordance of qualitative results according to distinct MFI cutoffs (1,000, 3,000, 5,000, and 10,000), and the correlation of quantitative MFI values obtained by the participating laboratories. The CV for MFI values were analyzed and grouped by mean MFI values from the five laboratories (<1,000; 1,000-2,999; 3,000-4,999; 5,000-9,999; and > or =10,000). RESULTS: The categorical results obtained from the five laboratories exhibited concordance rates of 96.0% and 97.2% for detection of HLA class I and class II antibodies, respectively. The Pearson correlation coefficients for MFI values of class I and class II antibodies were between 0.947-0.991 and 0.992-0.997, respectively. The median CVs for the MFI values among five laboratories in the lower MFI range (<1,000) were significantly higher than those for the other MFI ranges (all P<0.01). CONCLUSIONS: Analysis of SAB performed in five laboratories using identical protocols and reagents from the same lot resulted in high levels of concordance and strong correlation of results.
Analysis of Variance ; HLA Antigens/immunology ; Histocompatibility Testing ; Humans ; Isoantibodies/*blood ; Laboratories ; Reagent Kits, Diagnostic ; Reproducibility of Results

OBJECTIVETo detect platelet anti-HPA-1a and -1b antibodies using recombinant GPIIIa fragments coupled to Luminex beads.

METHODSThe sensitivity of 2 techniques, monoclonal antibody specific immobilization of platelet antigen (MAIPA) and Luminex bead assay, was compared using 12 twofold-serial dilutions (from neat to 1 in 2048) of an anti-HPA-1a WHO international standard. The specificity of Luminex assay to identify anti-HPA-1a and -1b antibodies was assessed using 8 negative or positive controls and 36 blinded samples provided by WHO Platelet Workshop.

RESULTSThe sensitivity of MAIPA and Luminex bead assay to detect anti-HPA-1a was dilution 1/64 (i.e. 1.56 IU/ml) and far more than dilution 1/2048 (i.e. 0.049 IU/mL), respectively. The Luminex bead assay could specifically identify negative and positive controls of anti-HPA-1a and -1b. All results of 36 blinded samples by Luminex assay were accordant to reference results except one sample which contained high concentration antithetical antibody and resulted in false positive of anti-HPA-1b. Cross-reactivity was also not observed with the samples containing HLA, ABO or other platelet antibodies.

CONCLUSIONThe Luminex beads coupled with recombinant GPIIIa fragments can be used to detect HPA-1 system antibodies with sufficient sensitivity and specificity, that is suitable for the detection of platelet alloantibodies in clinical alloimmune thrombocytopenia.

Antibodies, Monoclonal ; Antigens, Human Platelet ; immunology ; Blood Platelets ; Humans ; Integrin beta3 ; chemistry ; Isoantibodies ; blood ; Purpura, Thrombocytopenic, Idiopathic ; diagnosis ; Recombinant Proteins ; chemistry ; Sensitivity and Specificity

BACKGROUND: Duffy (FY) blood group genotyping is important in transfusion medicine because Duffy alloantibodies are associated with delayed hemolytic transfusion reactions and hemolytic disease of the fetus and newborn. In this study, FY allele frequencies in Thai blood donors were determined by in-house PCR with sequence-specific primers (PCR-SSP), and the probability of obtaining compatible blood for alloimmunized patients was assessed. METHODS: Five hundred blood samples from Thai blood donors of the National Blood Centre, Thai Red Cross Society, were included. Only 200 samples were tested with anti-Fy(a) and anti-Fy(b) using the gel technique. All 500 samples and four samples from a Guinea family with the Fy(a-b-) phenotype were genotyped by using PCR-SSP. Additionally, the probability of obtaining antigen-negative red blood cells (RBCs) for alloimmunized patients was calculated according to the estimated FY allele frequencies. RESULTS: The FY phenotyping and genotyping results were in 100% concordance. The allele frequencies of FY*A and FY*B in 500 central Thais were 0.962 (962/1,000) and 0.038 (38/1,000), respectively. Although the Fy(a-b-) phenotype was not observed in this study, FY*B(ES)/FY*B(ES) was identified by PCR-SSP in the Guinea family and was confirmed by DNA sequencing. CONCLUSIONS: Our results confirm the high frequency of the FY*A allele in the Thai population, similar to that of Asian populations. At least 500 Thai blood donors are needed to obtain two units of antigen-negative RBCs for the Fy(a-b+) phenotype.
Adult ; Alleles ; Asian Continental Ancestry Group/genetics ; Base Sequence ; Blood Donors ; DNA/chemistry/genetics/metabolism ; Duffy Blood-Group System/*genetics/immunology ; Female ; Gene Frequency ; Genotype ; Humans ; Isoantibodies/blood/immunology ; Male ; Middle Aged ; Phenotype ; Polymerase Chain Reaction ; Receptors, Cell Surface/genetics/*immunology ; Sequence Analysis, DNA ; Thailand ; Young Adult

To determine the approximate incidence and clinical features of pernicious anemia in a Korean population, we retrospectively analyzed clinical data for patients with pernicious anemia who were diagnosed between 1995 and 2010 at five hospitals in Chungnam province. Ninety-seven patients were enrolled, who accounted for 24% of patients with vitamin B12 deficiency anemia. The approximate annual incidence of pernicious anemia was 0.3 per 100,000. The median age was 66 (range, 32-98) yr, and the male/female ratio was 1.25. Anemia-associated discomfort was the most common symptom (79.4%), followed by gastrointestinal and neurological symptoms (78.4% and 38.1%, respectively). Pancytopenia was found in 36 patients (37.1%), and autoimmune disorders were found in 15 patients (15.5%). Antibody to intrinsic factor was detected in 62 (77.5%) of 80 patients examined, and antibody to parietal cells was detected in 35 (43.2%) of 81 patients examined. Of the 34 patients who underwent tests for Helicobacter pylori, 7 (12.5%) were positive. The anemia-associated and gastrointestinal symptoms resolved completely in all patients after intramuscular injection of cobalamin, whereas neurological symptoms remained in some. In conclusion, pernicious anemia is less frequent in Koreans than in Western populations; however, the clinical features of this disorder in Koreans do not differ from those of Western cases.
Adult ; Aged ; Anemia, Pernicious/complications/*diagnosis/epidemiology ; Asian Continental Ancestry Group ; Autoimmune Diseases/complications/epidemiology ; Female ; Gastrointestinal Diseases/complications/drug therapy/epidemiology ; Helicobacter Infections/diagnosis ; Helicobacter pylori ; Humans ; Isoantibodies/blood ; Male ; Middle Aged ; Nervous System Diseases/complications/epidemiology ; Parietal Cells, Gastric/immunology ; Republic of Korea/epidemiology ; Retrospective Studies ; Vitamin B 12/blood/therapeutic use

This study was aimed to analyze the serological characteristics, efficacy and safety of incompatible RBC transfusion in patients with autoimmune hemolytic anemia (AIHA). The patients with idiopathic or secondary AIHA were analyzed retrospectively, then the serological characteristics and the incidence of adverse transfusion reactions were investigated, and the efficacy and safety of incompatible RBC transfusion were evaluated according to the different autoantibody type and infused different RBC components. The results showed that out of 61 cases of AIHA, 21 cases were idiopathic, and 40 cases were secondary. 8 cases (13.1%) had IgM cold autoantibody, 50 cases (82.0%) had IgG warm autoantibody, and 3 cases (4.9%) had IgM and IgG autoantibodies simultaneously. There were 18 cases (29.5%) combined with alloantibodies. After the exclusion of alloantibodies interference, 113 incompatible RBC transfusions were performed for 36 patients with AIHA, total efficiency rate, total partial efficiency rate and total inefficiency rate were 56.6%, 15.1% and 28.3%, respectively. Incompatible RBC transfusions were divided into non-washed RBC group and washed RBC group. The efficiency rate, partial efficiency rate and inefficiency rate in non-washed RBC group were 57.6%, 13.0% and 29.4%, respectively. The efficiency rate, partial efficiency rate and inefficiency rate in washed RBC group were 53.6%, 21.4% and 25.0%, respectively. There was no significant difference of transfusion efficacy (P > 0.05) in two groups. Incompatible RBC transfusions were also divided into IgM cold autoantibody group and IgG warm autoantibody group. The efficiency rate, partial efficiency rate and inefficiency rate in IgM cold autoantibody group were 46.2%, 30.8% and 29.4%, respectively. The efficiency rate, partial efficiency rate and inefficiency rate in IgG warm autoantibody group were 56.7%, 13.4% and 29.9%, respectively. There was no significant difference of transfusion efficacy (P > 0.05 ) in two groups. Hemolytic transfusion reaction was not observed in all incompatible RBC transfusions. It is concluded that the same ABO type of non-washed RBC transfusion and O type washed RBC transfusion are all relatively safe for the AIHA patients with severe anemia after the exclusion of alloantibodies interference. There is no significant difference of transfusion efficacy in two groups. The same ABO type of non-washed RBC transfusion is more convenient and efficient than washed RBC transfusion, and excessive use of type O RBCs can also be avoided.
Adult ; Aged ; Aged, 80 and over ; Anemia, Hemolytic, Autoimmune ; diagnosis ; immunology ; therapy ; Blood Grouping and Crossmatching ; Erythrocyte Transfusion ; Female ; Humans ; Isoantibodies ; Male ; Middle Aged ; Treatment Outcome ; Young Adult

This study was purposed to detect the alloantibodies against Factor VIII (FVIII) by ELISA for estimating the incidence of the alloantibodies against Factor VIII (FVIII) in patients with hemophilia A, and to investigate the relationship between factor VIIIC domain and alloantibodies. Total of 140 patients with hemophilia A and 80 normal controls were enrolled in this study, among them plasma FVIII level of 84 patients was less than 1%, plasma FVIII level of 34 patients was between 1% and 5%, and plasma FVIII level of 22 patients was more than 5%. All patients were treated with plasma-derived FVIII concentrate or plasma before. The ELISA plate was coated with McAb (SZ-132) against FVIII prepared in our laboratory, then human recombinant FVIII concentrates were applied. After incubation in room temperature for 2 hours, diluted plasma samples and HRP-conjugated goat anti-human IgG were added successively, finally A490 was recorded. The threshold of alloantibody of patient plasma was set as mean value>3 SD more than control. The plate was coated with antibody against His, then human recombinant FVIII-C1C2 prepared in our laboratory was added. After incubation in room temperature for 2 hours, diluted plasma samples and HRP-conjugated goat anti-human IgG were added successively, finally A490 were recorded. The threshold was set as the mean value>3 SD more than control. The results showed that the alloantibodies against FVIII were found in 56 patients (40%) by ELISA, and 82.1% (46/56) of this kind of alloantibody could interact with the C domain of FVIII. It is concluded that C domain of FVIII is one of the primary binding sites for the alloantibodies against FVIII in Chinese patients with hemophilia A.
Adolescent ; Adult ; Binding Sites, Antibody ; Case-Control Studies ; Child ; Child, Preschool ; Factor VIII ; immunology ; Hemophilia A ; blood ; immunology ; Humans ; Infant ; Isoantibodies ; blood ; Male ; Middle Aged ; Protein Interaction Domains and Motifs ; Young Adult

Blood Coagulation Factor Inhibitors ; antagonists & inhibitors ; blood ; Factor VIII ; administration & dosage ; antagonists & inhibitors ; immunology ; Hemophilia A ; drug therapy ; genetics ; immunology ; Humans ; Immune Tolerance ; Isoantibodies ; blood ; immunology ; Recombinant Proteins ; adverse effects ; immunology ; therapeutic use ; Risk Factors ; Time Factors

BACKGROUND: Introduction of the Luminex panel reactive antibody (PRA)-single antigen (SA) assay has increased the detection rates of unacceptable antigens in sensitized patients; the calculated PRA (CPRA) level represents the percentage of actual organ donors that express 1 or more of these unacceptable antigens. We developed a CPRA calculator based on the HLA frequencies in Koreans to measure sensitization levels in Korean patients. METHODS: To develop the calculator, we obtained the HLA-A, HLA-B, and HLA-DR phenotypes of 1,622 Koreans, and compared these with previously reported frequencies in Koreans. Sera from patients awaiting kidney transplantation were tested for HLA antibodies by Luminex PRA-screen, PRA-identification (ID), and PRA-SA assays. The measured %PRA from the PRA-screen (N=55) and PRA-ID (N=71) were compared to the %CPRA for the unacceptable antigens obtained from PRA-SA. RESULTS: Phenotype frequencies used for the CPRA calculator agreed with previously reported data. The concordance rates among the 3 PRA methods for the detection of class I and class II antibodies were 76.1-81.8% (kappa, 0.519-0.636) and 72.7-83.6% (0.463-0.650), respectively. For the detection of broadly sensitized sera (>50% or >80%), the concordance rates were over 80%. In sera with 80-100% CPRA, 91.7% and 94.4% of the samples had concordant results (80-100% PRA) in the PRA-screen and PRA-ID assay, respectively. CONCLUSIONS: Although further clinical studies are required to confirm the benefits of CPRA values, adoption of CPRA analysis based on HLA frequencies in Koreans may be useful for sensitization measurements and organ-allocation algorithms.
*Algorithms ; HLA Antigens/immunology ; HLA-B Antigens/immunology ; HLA-DR Antigens/immunology ; *Histocompatibility Testing ; Humans ; Isoantibodies/*blood/immunology ; Phenotype ; Republic of Korea

In order to analyze the genotype of RhD-negative blood donors with immune antibodies in Harbin, the voluntary blood donors from 1 April 2008 to 30 september 2011 were detected serologically to determine the RhD-negative donors. The blood donors confirmed to be RhD negative were detected to screen the immune antibodies, the samples with immune antibodies were analyzed by PCR-SSP and DNA sequencing to detect RhD genotype. The results showed that the 12 cases of the immune antibodies (0.95%) were screened out from 1265 cases of RhD-negative donors, among which 9 cases showed anti-D-antibody, 3 cases showed anti-(D+C) antibody; 10 cases were RhD-negative, 2 cases were RHD 711D(el)C. It is concluded that RhD negative and RHD 711D(el)C are easy to be immunized to produce the immune antibodies; RhD-negative population, especially women should be highly aware of avoiding mis-transfusion of RhD-positive blood, and also avoiding multiple pregnancies resulting in newborn's hemolytic disease.
Base Sequence ; Blood Donors ; Exons ; Genotype ; Humans ; Isoantibodies ; Phenotype ; Rh-Hr Blood-Group System ; genetics ; immunology ; Rho(D) Immune Globulin