anti-B Sera Research Articles

Detection of weak A antigen associated with Proteus vulgaris infection

Background: A person with weak A antigen expression is presented. Objectives: The study aimed to reveal weak A antigen by different methods applied in laboratories. Materials and methods: The reaction of adsorption, agglutination, and inhibition of agglutination were performed at 4 °C, 10 °C, 13 °C, 20 °C, and 37 °C for 1-13 hrs and one-day incubation. The complement of the guinea pig was added to the heated serum to reveal hemolysis. Results: A person’s red blood cells reacted with commercial anti-B sera. Whereas anti-A and anti-B (reactive at 37 °C) antibodies were found in the serum. The person demonstrated anti-A antibody adsorbing ability at 4 °C. The plasma of the person inhibited agglutination of A and B RBCs by polyclonal sera. The blood culture was positive for Proteus vulgaris infection. Conclusion: The presence of weak A antigen was detected the best by the adsorption method at low temperatures with polyclonal sera from the O blood group.

Group antibodies as factors specifically influencing erythrocytes sedimentation rate

The use of the erythrocyte sedimentation rate (ESR) method has been recognized in monitoring the inflammation process, with a proven role of proinflammatory factors in the ESR increase. The aim. To reveal the role of group antibodies in the specific increase of ESR. Methods. For the study erythrocytes with EDTA anticoagulant were used. ESR was measured after the contact of erythrocytes with saline (negative control), standard anti-A and anti-B antibodies of the IgM class, polyclonal anti-A, anti- B, anti-A, B sera (experiment), as well as serum of group AB in a ratio 1 : 3: 0.2 ml of erythrocytes and 0.6 ml of saline or serum. The results were evaluated after one and 12 hours of incubation, at room temperature and at 4 °C. Results. Contact of anti-A IgM antibodies at a dilution of 1 : 30 with A erythrocytes led to an increase of ESR (from (3.25 ± 0.50) mm/h to (83.7 ± 1.60) mm/h) (p < 0.001) with a presence of a red precipitate. The contact of erythrocytes with polyclonal citrate plasma (or serum) in a ratio of 1 : 2 led to a similar increase in ESR in cases of the specific binding. Anti-A, B serum increased ESR of A erythrocytes up to (53.00 ± 2.64) mm/h (p < 0.001) with the presence of a red precipitate, while anti-B serum did not show such effect: (ESR — (5.25 ± 0.50) mm/h) (p > 0.05). It should be noted that the serum absorbed by the corresponding erythrocytes showed reduced ESR values. After the absorption of anti-A antibodies by A erythrocytes the serum lost the ability to specifically increase the ESR of A erythrocytes. Conclusions. Group antibodies are able to specifically promote ESR. The found ability can be reduced by the method of specific absorption of the serum. The physicians may consider the role of group specific autoimmune antibodies in developing high values of ESR. The therapy aimed to regulate the autoimmune humoral activation and specific absorption might be useful in normalization the ESR parameter.

Method for ABO Blood Group Testing Using a General-Purpose Automated Biochemical Analyzer.

We investigated a high-throughput and high-precision forward ABO blood typing screening method that utilizes a general-purpose biochemical analyzer to perform direct red blood cell sampling. The blood group antisera used were Ortho® BioClone® Anti-A Serum and Ortho® BioClone® Anti-B Se-rum. AFFIRMAGEN® Reagent Red Blood Cells (Ortho Clinical Diagnostics) were used for AB standard red blood cells. The general-purpose biochemical analyzer employed was the TBATM-120FR HbA1c measurement unit (Canon Medical Systems). ABO blood group of patient samples was determined based on values relative to amount of change in the AFFIRMAGEN® response. Repeatability was CV5% or lower, and testing of 1,112 patient samples showed 100% agreement between the results obtained using the proposed method and those obtained using the tube test method. The proposed method allows ABO blood typing to be performed simply, quickly, and with a high degree of precision.

Blood group pattern and its distribution among blood transfusion recipients in a semi-urban setting in North-West Nigeria

Background: The blood group refers to the blood grouping system and their specificity which is genetically determined; however, the “blood phenotype” describes the reactivity of blood to specific testing antiserum. Although racial and regional variations have been established in the prevalence of the blood groups, most of these studies were done among blood donors, but the blood transfusion recipients who actually need these transfusions have been poorly studied. This study seeks to determine the common blood groups encountered among blood transfusion recipients in Federal Medical Centre (FMC), Birnin Kudu. Materials and Methods: This study was a retrospective analysis of the blood grouping pattern among blood transfusion recipients in FMC, Birnin Kudu over a 2-year period from January 2011 to December 2013. Blood grouping is determined commonly using venous blood through tile agglutination method. Standard commercially produced anti-A, anti-B monoclonal grouping reagents and anti-D sera are used for the tests and performed at room temperature. Evidence of agglutination is substantiated microscopically after waiting for 2 min. Results: There were 4129 blood requests during the study period; however, 28 of the entries were excluded due to grossly incomplete data. Among the 4101 entries analyzed, there were 1206 (29.4%) males and 2895 (70.6%) females; male/female ratio of 1:2.4. Blood group O (44.1%) was the most common blood group whereas blood group AB (5.9%) was the least; however, majority (96.2%) of the recipients were rhesus positive. Conclusion: Group O and rhesus positive antigens remain the most common blood group distribution among blood transfusion recipients.

Preparation and evaluation of laboratory quality control materials for the detection of IgG anti-A/B

Abstract Background: This research was aimed at preparing laboratory quality control materials for the detection of IgG anti-A/B and evaluating them in preliminary applications. Methods: Mixed IgG anti-A and anti-B sera were used as quality controls for measuring IgG anti-A/B titers. The quality control materials were packaged with sodium azide as preservative, and stored at –30°C. Twenty repeated measurements were done in succession. After the quality control values were determined, the quality control materials were used preliminarily. Quality controls and the untested blood samples were assayed at the same time within 6 months. Results: The mean IgG anti-A titer of the high-value quality control serum was 1:550 and ranged from 1:225 to 1:1100 for the control. The mean IgG anti-B titer of the high-value quality control serum was 1:269 and ranged from 1:135 to 1:538 for the control. The mean IgG anti-A and B titer of the low-value control serum was 1:32, with a quality control range of 1:16–1:64. Conclusions: Laboratory quality control materials in the measurement of IgG anti-A/B titers were developed successfully. Standardization of the assay procedure and quality control survey would be necessary for the accuracy of measurement.

Genetical study of mutation in maternal-fetal ABO incompatibility.

This study looked into a family involving a rare mother-child ABO blood type inconsistency and explored its genetic and molecular basis. In the family, the mother had type AB blood and the father was blood type B and they gave birth to a baby of blood type O. Their blood types were phenotypically identified by using different techniques, including micro-column gel test, immune inhibition test, absorption and elution tests. The sequences of all 7 exons of ABO allele from the core family members were determined by using PCR and clone-based sequencing. The loci of mutated gene were compared against normal human genes. The result showed that the mother's erythrocytes were agglutinable with monoclonal anti-A antibody (2+) and had agglutination reaction with anti-B antibody (4+). The mother's serum registered agglutination action with standard blood type A cells. The findings showed an ABO inconsistency. When domestic antibodies were used, the mother's erythrocytes yielded agglutination reaction with humanized anti-B serum (4+) and anti-B monoclonal antibody but were non-agglutinable with humanized anti-A serum and anti-A monoclonal antibody. Upon absorption and elution, the titer of anit-A antibody was 128 both before and after the absorption test, with no significant difference found between pre- and post-absorption values. Our results confirmed that the mother's allelic gene was type B and contained type A. The father's blood type was type B, and son's blood type was type O. Clone-based sequencing revealed that the mother carried a heterozygous gene of B101.01 (ntA640→G)/O01, which contained an M214→V mutation that could express a weak expression of antigen A, resulting in blood type AB. However, their son did not have the M214→V mutation, which yielded a false ABO-inconsistency between him and his mother. We were led to conclude that type B gene with a M214→V mutation can encode both antigen B and weak antigen B that can lead to false ABO-inconsistencies.

Role of the Asymmetry of the Homodimeric b2 Stator Stalk in the Interaction with the F1 Sector of Escherichia coli ATP Synthase

The b subunit dimer in the peripheral stator stalk of Escherichia coli ATP synthase is essential for enzyme assembly and the rotational catalytic mechanism. Recent protein chemical evidence revealed the dimerization domain of b to contain a novel two-stranded right-handed coiled coil with offset helices. Here, the existence of this structure in more complete constructs of b containing the C-terminal domain, and therefore capable of binding to the peripheral F1-ATPase, was supported by the more efficient formation of intersubunit disulfide bonds between cysteine residues that are proximal only in the offset arrangement and by the greater thermal stabilities of cross-linked heterodimers trapped in the offset configuration as opposed to homodimers with the helices trapped in-register. F1-ATPase binding analyses revealed the offset heterodimers to bind F1 more tightly than in-register homodimers. Mutations near the C terminus of b were incorporated specifically into either the N-terminally or the C-terminally shifted polypeptide, bN or bC, respectively, to determine the contribution of each position to F1 binding. Deletion of the last four residues of bN substantially weakened F1 binding, whereas the effect of the deletion in bC was modest. Similarly, benzophenone maleimide introduced at the C terminus of bN, but not bC, mediated cross-linking to the delta subunit of F1. These results imply that the polypeptide in the bN position is more important for F1 binding than the one in the bC position and illustrate the significance of the asymmetry of the b dimer in the enzyme.

Influence of the hematopoietic stem cell source on early immunohematologic reconstitution after allogeneic transplantation

AbstractSeveral acute hemolysis episodes, sometimes lethal, have been recently described after transplantation of allogeneic peripheral blood hematopoietic stem cells (PBHSCs). Hemolysis resulted from the production of donor-derived antibodies (Abs) directed at ABO antigens (Ags) present on recipient red blood cells (RBCs). A multicenter randomized phase III clinical study comparing allogeneic PBHSC transplantation (PBHSCT) versus bone marrow hematopoietic stem cell transplantation (BMHSCT) has been conducted in France. In the course of this study, serum anti-A and/or anti-B Ab titers were compared before the conditioning regimen and on day +30 after transplantation in 49 consecutive evaluable PBHSCT (n = 21) or BMHSCT (n = 28) recipients. PBHSCT resulted in a higher frequency of increased anti-A and/or anti-B Ab titers 30 days after transplantation as compared to BMHSCT: 8 (38%) of 21 versus 3 (11%) of 28 (P = .04). In PBHSCT recipients, increased titers were observed mostly after receiving a minor ABO mismatch transplant: 5 of 7 versus 3 of 14 in the absence of any minor ABO mismatch (P = .05), whereas this was not the case after BMHSCT: 1 of 8 versus 2 of 20. Anti-A and/or anti-B serum Abs detectable at day +30 after PBHSCT were always directed against A and/or B Ags absent both on donor and recipient RBCs. Finally, 3 of 21 PBHSCT versus 0 of 28 BMHSCT recipients developed anti-allogeneic RBC Abs other than ABO (P = .07). Overall, the data strongly suggest that immunohematologic reconstitution differs significantly after granulocyte colony-stimulating factor–mobilized PBHSCT when compared to BMHSCT. Such a difference could contribute to the acute hemolysis described after PBHSCT as well as to distinct alloreactivity after PBHSCT.

Easy method for determining the frequency of O1 and O2 alleles in Brazilian blood donors by PCR-RFLP analysis

Abstract Serologic ABO blood typing is routinely performed using anti-A and anti-B sera to distinguish four phenotypes (A, B, AB, and O). Restriction fragment length polymorphisms (RFLPs) and DNA sequence studies offer the possibility of direct ABO genotyping. We used polymerase chain reaction-RFLP analysis to determine the frequency of O1 and O2 alleles in 82 unrelated blood donors in São Paulo, Brazil, known to be group O. Genomic DNA was extracted from blood leukocytes by a modified salting-out method. Different genotypes (O1O1, O1O2, O2O2) were identified after digestion with restriction enzymes KpnI, HpaII, and AluI, followed by agarose gel electrophoresis. Of 82 samples analyzed, 74 were O1O1 , 7 were O1O2 , and 1 was O2O2 . These results showed the frequency of O1O1, O1O2 , and O2O2 genotypes to be 90.24 percent, 8.53 percent, and 1.22 percent, respectively, in blood donors in São Paulo, Brazil. Immunohematology 2001;17:111–116.

Anti-Human Class I α3 Domain-Specific Monoclonal Antibody Induces Programmed Cell Death in Murine Cells Expressing Human Class I MHC Transgenes

In vivo and in vitro methods were used to determine whether JMV Marek's disease (MD) tumor cells have B-cell or T-cell characteristics. JMV tumor cells were treated with anti-T-cell serum (ATS) and complement (C) or anti-B serum (ABS) and C and then inoculated into 1-day-old chickens. Within 2 weeks of inoculation, 95% of chickens inoculated with ATS- and C-treated cells died of JMV-induced leukemia, whereas only 10% of chickens inoculated with ABS- and C-treated cells succumbed. This in vivo result indicated that the malignant cells may be B cells. In vitro studies corroborated this conclusion. ABS and C killed 99 to 100% of cultivated JMV cells, whereas little or no killing of JMV cells was achieved by ATS and C, as demonstrated by trypan blue dye exclusion or by release of 51Cr from labeled JMV cells. Furthermore, after staining of JMV cells with fluorescein-conjugated rabbit anti-chicken immunoglobulin, all cells fluoresced, indicating that JMV cells have surface immunoglobulin. With support of these lines of evidence, we conclude that JMV Marek's disease tumor cells have B-cell characteristics.

STUDY ON PREPARATION AND APPLICATION OF ANTI-B1 SERUM

In examining donors serologically, we found a case of A1B2 subgroup and got anti-B1 serum through absorbing anti-B serum by the A1B2 red cells. Then we successfully identified bint subgroup and classified B blood group into subgroup B1 and B2. The results indicated that the frequency of B2 subgroup was only about 0.02% in people with B and AB blood groups. Key words: Blood group; anti-B1 antibody.

血液型Ｏで抗Ａ抗体活性を欠失した稀な１女児例

A Japanese girl with blood phenotype O who is complicated with a rare deficiency of selective anti-A agglutinin is described. (A) Tests for patient red blood cell (RBC): Commercial anti-A or anti-B serum did not agglutinate the patient RBCs. Neither anti-A nor anti-B agglutinin activity was recovered from patient RBCs by absorption-elution experiment according to the method of Landsteiner & Miller. Flowcytometric analysis revealed that patient RBC is totally lacked of immunoreactive material against both anti-A and anti-B antibodies. (B) Patient serum: Patient serum preferentially agglutinated RBCs from type B individuals, but not from type A individuals. Both the activities of A-and B-transferase in the patient serum were undetectable. In patient saliva, excretion of H-substance was indicated by inhibition test using anti-H lectin (Ulex-lectin). Furthermore, neither the presence of irregular antibodies nor quantitative decrease of immunoglobulins G, A, and M was observed in patient serum. Studies of her family members confirmed that the propositus was an only patient having blood phenotype O which lacked anti-A agglutinin activity despite of normal expression of anti-B agglutinin.

A repeated proline-rich sequence in Sm B/B′ and N is a dominant epitope recognized by human and murine autoantibodies

Reactivity of a murine monoclonal anti-Sm B antibody was localized to a cDNA clone T3/2 encompassing codons 177-221 of Sm N and to a series of 10-residue synthetic peptides containing a proline-rich motif. Human sera containing anti-B antibodies also bound to this proline-rich motif in the form of a heptamer, PPGMRPP, and could distinguish the N/B sequence from similar sequences present in the RNP A and C polypeptides in a number of cases. Monoclonal antibodies binding to either this peptide or to a determinant present on both B and D polypeptides inhibited the majority of anti-B binding in 50% of anti-B sera. The region of N/B containing PPGMRPP also bears a second epitope, sterically blocked by monoclonal antibody KSm 5. This hotspot binds 40-60% of anti-B activity in 30% of anti-B sera. These data suggest that the anti-Sm B epitope recognition repertoire is restricted in SLE patients.

Distribution of A and B antigens in organs of blood group AB individuals: observations disclosed by a double immunoenzymatic labeling method

The localization of A and B antigens in the organs of blood group AB individuals has been studied using a double immunoenzymatic labeling method. Both A and B antigens were found in the various epithelial cells of these organs, but the epithelial cells could be classified into the following four types depending on the reaction pattern with anti-A and anti-B sera: type 1: cells that stained positive with both anti-A and anti-B sera; type 2: cells that stained positive with anti-A serum only; type 3: cells that stained positive with anti-B serum only; type 4: cells that were negative with both sera. The distribution of each of these epithelial cell types varied considerably, even in the same tissue and individual. Our results seem to suggest that a dissociation in the conversion to the A and B antigens occurs in the tissue of individuals belonging to blood group AB and that the degree of this dissociation varies from tissue to tissue and from cell to cell.

Distribution of A and B antigens in organs of blood group AB individuals: Observations disclosed by a double immunoenzymatic labeling method

The localization of A and B antigens in the organs of blood group AB individuals has been studied using a double immunoenzymatic labeling method. Both A and B antigens were found in the various epithelial cells of these organs, but the epithelial cells could be classified into the following four types depending on the reaction pattern with anti-A and anti-B sera: type 1: cells that stained positive with both anti-A and anti-B sera; type 2: cells that stained positive with anti-A serum only; type 3: cells that stained positive with anti-B serum only; type 4: cells that were negative with both sera. The distribution of each of these epithelial cell types varied considerably, even in the same tissue and individual. Our results seem to suggest that a dissociation in the conversion to the A and B antigens occurs in the tissue of individuals belonging to blood group AB and that the degree of this dissociation varies from tissue to tissue and from cell to cell.

A sensitive enzyme-linked immunosorbent assay used to differentiate type AB specimen from a mixture of type A and type B specimens

A sensitive enzyme-linked immunosorbent assay (ELISA) for detection of ABO blood substances in human body fluids was devised. The ELISA plates coated with purified human anti-A or anti-B serum effectively captured the blood substances, and these were then analysed by the combination of rabbit anti-A and goat anti-B. This capture ELISA could differentiate the type AB specimen from a mixture of the type A and the type B specimens, and the method was applied to rape cases to make the ABO typing of the criminal.

The role of antibody density in the immune lysis of sensitised erythrocytes. A mathematical appreciation.

The influence of sensitizing antibody density on target cell selection by effector monocytes was examined by modifying the sensitization of red cells either by dilution of the antiserum, variation of the number of erythrocytes or both in a cold target competition assay of antibody-dependent cellular cytotoxicity (ADCC). Human A1 and B erythrocyte target and competitor cells were employed in the presence of hyperimmune anti-A and anti-B sera at concentrations above that necessary for saturation of red cells with respect to lytic susceptibility. When the number of red cells was kept constant and the dilution of antisera was varied a linear relationship between the competitive capacity of erythrocytes and the concentration of sensitizing antiserum was observed. When the number of target (competitor) cells and the concentration of antisera were varied simultaneously it was apparent that the competitive capacity was dependent upon the relative densities of the sensitizing antibodies. When competition was tested in the presence of suboptimal concentrations of complement, rather than effector cells it was observed that, in common with ADCC, the effectiveness of cold competition was dependent upon the concentration of sensitizing antibody.

Two forms of guinea pig factor B of the alternative complement pathway with different molecular weights

Two forms of guinea pig factor B (B) of the alternative complement pathway with different mol. wts ( M r) have been isolated from plasma and characterized. The M r of the two B species, tentatively termed B1 and B2, were estimated to be about 100,000 and 96,000, respectively, as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Incubation of B with guinea pig C3 and human factor D (D) in the presence of Mg 2+ generated two cleavage fragments of B, namely Ba and Bb. Although the Bb fragments showed the same migration corresponding to an M r of 62,000, Ba fragments showed different mobilities corresponding to an M r of 38,000 from B1 and 34,000 from B2. Digestion of B1-Ba, the Ba fragment derived from B1, and B2-Ba, the Ba fragment derived from B2, with endoglycosidase F resulted in a band at M r 30,000 on an SDS-PAGE in both cases, indicating a difference in structure of the asparagine-linked oligosaccharide moiety in B1-Ba and B2-Ba. No difference in antigenicity was noted between B1 and B2 on immunodiffusion with anti-B sera. Immunoblotting analysis showed that all individual Hartley guinea pigs examined in this study possessed both B1 and B2 at similar levels, as determined by the intensity of staining of their sera. Furthermore, treatment of their serum with zymosan led to the generation of two Ba species corresponding to the Ba fragments from B1 and B2. The capacity to form C3/C5 convertase, as determined by hemolytic assay, was found to be similar between B1 and B2. Furthermore, kinetics of the decay of C3 convertase showed the same half-life of 3.0 min at 30°C. The NH 2-terminal amino acid sequences of B1 and B2 and their Bb fragments were determined and found to be identical.

The Two Antibody Specificities Within Human Anti-Blood Group B Antibodies

ANTIBODIES to blood group antigens have been regarded as natural anticarbohydrate antibodies with an absolute specificity to the wellcharacterized blood group A or B antigenic epitopes.I ,2 However, long before the determination of blood group antigen structures, Landsteiner and Miller observed that anti-B antibodies are in fact heterogeneous antibodies recognizing more than one antigen. They found that whereas New World monkey red cells are agglutinated byhuman anti-B antibodies, these red cells do not bind anti-B antibodies from sera of rabbits immunized with Bred cells. 3 This suggested that human anti-B sera contain, in addition to antibodies reacting with B antigen, antibodies directed toward a different antigenic structure that closely resembles B antigen, designated B-like antigen. B-like antigen was assumed to be present on New World monkey red cells, but absent from human, ape, and Old World monkey red cells. 3 These early observations were confirmed thereafter by other investigators as well. 4 Furthermore, Owen found that rabbit red cells also express B-like antigen, which can adsorb only a portion of human anti-B antibody reactivity. The fact that B-like antigen on rabbit red cells is different from B-antigen on human red cells was also evident from the finding that after immunization with B red cells, rabbits produce highly reactive anti-B antibodies. 3,7 The present work reviews some of our recent studies that explain the Band B-like specificities of antibodies within human anti-B sera. We found B-like antigen to be the Galal~3Gal epitope, which differs from B antigen in lacking the fucosyl residue which, in B antigenic epitopes, are linked

Examinations of ABO bloodgroupings of human hair

In order to bring into play the function of human hair ABO bloodgrouping in the field of medicolegal expertise on material evidence and raise its accuracy, the author, through a test on human hair of 500, makes some emphatic researches on the disposal of hairs, on the application of anti-A and anti-B serum, on the selection of red blood cell indicator and on the elution temperature as well. Five hundred samples of human hair have been examined upon the basis of the improved operation method and through the application of anti-A and anti-B serum, the titer of which being 1:128, and therein, fine results have been obtained.