Immucor (United States)

ABO antibody titres are important in many clinical decisions; however, much variability is observed in titre results. For reliable and reproducible titre results, automated ABO titration methods have been developed. In this 10-site study, we evaluated the equivalency of the automated ABO titration assays on the Galileo NEO, a fully automated blood bank analyzer (Immucor, Inc.) to manual titration with gel Column Agglutination Technology (CAT), as well as the reproducibility of both methods. Ten different locations participated in this study. The equivalency study included 70 random samples at each site. The reproducibility study tested the same blinded 30-sample panel at each study site. Anti-A and anti-B IgM and IgG antibody titres were tested with both the automated and manual methods; additionally, dithiothreitol (DTT) treatment was used to inactivate IgM antibodies in the manual CAT method. The equivalency between CAT manual method and Galileo NEO automated titres at each site ranged from 38 to 88%; equivalency for each isotype was 66.2% for IgM, 60.6% for IgG, and 88.5% for DTT-treated IgG. The reproducibility study evaluated the titre variation of each sample obtained from the 10 sites. The average titre ranges (in doubling dilutions) for the automated and manual methods, respectively, were 2.15±1.0 and 4.03±1.8 for IgM, and 1.53±0.7 and 4.10±1.9 for IgG; for the manual DTT-treated IgG, the average titre range was 3.45±1.8 doubling dilutions. The results demonstrated that the Galileo NEO automated and manual CAT ABO titres are not equivalent. However, the study also demonstrated that titre reproducibility is enhanced with the Galileo NEO automated ABO titration assays relative to the manual CAT ABO titration method. Therefore, to improve management of patients receiving care across multiple institutions, our study supports the use of automated ABO titration.

The risk of hepatitis E virus (HEV) infection from blood transfusion has raised increasing concern in many countries. Several transfusion-transmitted cases have been described in the United Kingdom and Japan. The objective was to investigate the prevalence of HEV infection among Chinese blood donors and analyze the potential risk of HEV infection through blood transfusion in China. Major English and Chinese research databases were used as background research for the study of locations, years, and the number of HEV infections among blood donors in China. The pooled, estimated rate of HEV infection was calculated. Subgroup analyses, for age, sex, and alanine aminotransferase (ALT) levels were performed using software for comprehensive meta-analysis. The pooled rates of anti-HEV IgM- and anti-HEV IgG-positive donations were 1.09% (95% confidence interval [CI], 0.95%-1.26%) and 30% (95% CI, 25%-34%), respectively. The prevalence of anti-HEV IgM was significantly higher in donors with elevated ALT (4.34%) compared with the rate in donors with normal ALT (1.35%; χ2 = 39.66, p < 0.01). The anti-HEV IgM and IgG rates were higher in the Southwest region (1.58 and 41%, respectively) compared to the rates in other regions of China (chi-square test, p < 0.05). The anti-HEV IgG rate was also significantly higher in donors 30 years and older compared with donors between 18 and 29 years of age (39% vs. 22%, respectively; χ2 = 1457.10, p < 0.01). Genetic analysis of HEV from RNA-positive donors indicated that the majority of HEV infections were Genotype 1 (19/33 = 58%), while the remaining 14 isolates were Genotype 4 (14/33 = 42%; χ2 = 0.758, p > 0.05). Qualified donations after routine blood donor screening still carry a potential risk for transmitting HEV. The major genotypes in Chinese donors in this study were Genotypes 1 and 4.

78-year-old African-American man. Chronic lymphocytic leukemia first diagnosed in 2003, with a subsequent relapse in 2006 and another in 2010. In late 2011, the patient was admitted to the hospital for cholelithiasis, at which time his treating physician incidentally discovered severe anemia. The anemia worsened as time went on, and the patient became transfusion dependent. Hypogammaglobulinemia secondary to chronic lymphocytic leukemia (CLL) required that the patient receive intravenous immunoglobulin. Despite transfusion therapy, the anemia failed to lessen; laboratory results eventually led to the diagnosis of a drug-induced warm autoantibody that triggered hemolytic anemia. The patient had taken rituximab in 2003; rituximab, cyclophosphamide, hydroxydaunorubicin, oncovin, and prednisone (R-CHOP) in 2006; fludarabine, cyclophosphamide, and rituximab (FCR) in 2010; and intravenous Immunoglobulin (IVIG) and prednisone in 2011.

The performance of a newly developed Luminex bead-based platelet (PLT) antibody detection method (PAKLx) was compared with the monoclonal antibody immobilization of PLT antigens (MAIPA) assay and the LifeScreen Deluxe Luminex bead-based HLA Class I antibody detection method (LMX). Six sera containing anti-human PLT antigen (HPA)-1a (n=2), HPA-1b, HPA-2b, HPA-3a, or HPA-5b were tested in titration. A total of 194 sera, including HPA-1a, -1b, -2a, -2b, -3a, -5a, and -5b antibodies with or without HLA antibodies (n=63); glycoprotein (GP) IV antibodies (n=1); PLT autoantibodies (n=3); HLA antibodies (n=45); and samples with no PLT-reactive antibodies (n=82), were tested in both assays. Comparable levels of sensitivity were obtained for the MAIPA and PAKLx. The PAKLx showed four (6%) false-negative results in 67 sera with HPA or GP-reactive antibodies: anti-HPA-3a (n=1) or anti-HPA-5b (n=3). The PAKLx showed in 10 of the total 194 samples (5%) the presence of antibodies not detected by the MAIPA. This concerned broadly GP-reactive antibodies (n=7), anti-GPIIb/IIIa combined with anti-HPA-3a (n=1), anti-HPA-1a (borderline, n=1), and anti-GPIV (n=1). Testing 175 sera for anti-HLA Class I antibodies in the PAKLx and LMX showed four discrepant results: PAKLx negative and LMX positive, n=3 and n=1, respectively. For the vast majority of the specimens tested (93%) the results of the PAKLx were in concordance with the MAIPA. The PAKLx is a fast, easy to perform, and sensitive PLT antibody screening method.

KEL1, also known as "K", is one of the most immunogenic red blood cell (RBC) antigens. KEL2, also known as "k," differs from KEL1 by a single amino acid. Anti-Kell system antibodies can lead to significant adverse clinical outcomes in humans, including hemolytic complications in alloimmunized transfusion recipients or in infants of alloimmunized mothers. To provide a platform for in-depth immunologic studies of alloimmunization and subsequent sequelae, we generated transgenic mice expressing the human KEL1 or KEL2 antigens. Vectors were created in which cDNAs encoding either KEL1 or KEL2 were regulated by an erythroid specific β-globin promoter and enhancer. Pronuclear microinjections were carried out into a C57BL6 background, and founder pups were identified by polymerase chain reaction and screened for expression by flow cytometry. RBC life span and antigen stability were assessed by dye labeling RBCs, transfusing into agammaglobulinemic (µMT) recipients, and tracking by flow cytometry. The expression of either KEL1 or KEL2 is RBC specific and first occurs on early RBC precursors. Both KEL1 and KEL2 RBCs have a normal circulatory life span and stable antigen expression. Expression of KEL1 or KEL2 does not result in altered levels of murine Kell, and resulting RBCs have normal hematologic variables. The KEL1 and KEL2 mice represent the first murine system of RBC immunity with antithetical antigens, allowing a more precise modeling of human RBC immunology in general and also a platform for development of novel therapeutics to prevent or minimize the dangers of RBC alloimmunization to the KEL1 and KEL2 antigens in particular.

This chapter provides an overview of key elements of the bead array technology and related manufacturing steps as well as key components in the deployment of the BeadChip™ system. The BeadChip™ molecular immunohematology has a spectrum of applications which can utilize multianalyte (multiplex) nucleic acid and protein analysis by Random Encoded Array Detection.