PubMed Health⌕ Search

Biomedical subjects

J Bux

Publications and source records attributed to J Bux.

At least 19 recordsLinked to original sources

Genotyping of human neutrophil antigen-5a (Ond).

Antibodies to human neutrophil alloantigens (HNA) can cause immune-mediated neutropenias and transfusion complications. The diagnosis of antibodies to the HNA-5a (Ond) isoform of the alphaLbeta2 integrin is hampered by the lack of reliable methods for HNA-5a antigen typing. We have devised a polymerase chain reaction sequence-specific primer method (PCR-SSP) and used it to determine the HNA-5a gene frequencies in 320 individuals from different ethnicities. 15.3% were found to be HNA-5a negative, with no significant deviation between the populations. Results of HNA-5a genotyping were in accordance with phenotyping. Availability of HNA-5a PCR-SSP will facilitate the diagnosis of Ond antibody-mediated clinical conditions.

Alleles↗

Transfusion-related acute lung injury (TRALI): a serious adverse event of blood transfusion.

BACKGROUND AND OBJECTIVES: Analyses of fatal transfusion reactions in the UK and USA have shown that transfusion-related acute lung injury (TRALI) is among the most common causes of fatal transfusion reactions. MATERIAL AND METHODS: Review of the literature was used to analyse TRALI. RESULTS: TRALI is characterized by acute respiratory distress and non-cardiogenic lung oedema developing during, or within 6 h of, transfusion. In atypical cases, TRALI can become symptomatic much later. TRALI must be carefully differentiated from transfusion-associated circulatory overload. In its fulminant presentation, TRALI can be clinically indistinguishable from acute respiratory distress syndrome occurring as a result of other causes. The severity of TRALI depends upon the susceptibility of the patient to develop a more clinically significant reaction as a result of an underlying disease process, and upon the nature of triggers in the transfused blood components, including granulocyte-binding alloantibodies (immune TRALI) or neutrophil-priming substances such as biologically active lipids (non-immune TRALI). Immune TRALI, which occurs mainly after the transfusion of fresh-frozen plasma and platelet concentrates, is a rare event (about one incidence per 5000 transfusions) but frequently ( approximately 70%) requires mechanical ventilation (severe TRALI) and is not uncommonly fatal (6-9% of cases). Non-immune TRALI, which occurs mainly after the transfusion of stored platelet and erythrocyte concentrates, seems to be characterized by a more benign clinical course, with oxygen support sufficient as a form of therapy in most cases, and a lower mortality than immune TRALI. CONCLUSIONS: By virtue of its morbidity and mortality, TRALI has become one of the most serious current complications of transfusion. To prevent further antibody-mediated cases, the evaluation of TRALI should include leucocyte antibody testing of implicated donors. However, further studies are necessary for the prevention of this serious transfusion complication.

Blood Donors↗

Neutrophil CD177 (NB1 gp, HNA-2a) expression is increased in severe bacterial infections and polycythaemia vera.

The NB1 glycoprotein (CD177, HNA-2a antigen) is exclusively expressed on human neutrophils. As the clinical significance of CD177 expression is unknown, we investigated its expression in healthy individuals before and after stimulation with granulocyte colony-stimulating factor (G-CSF), in patients with rheumatoid arthritis, viral hepatitis, severe bacterial infections and polycythaemia vera. Expression was quantitatively determined by flow cytometry and by real time polymerase chain reaction. Only G-CSF-stimulated individuals and patients with severe bacterial infections and polycythaemia showed a significantly (P < 0.001) increased CD177 expression compared with healthy individuals, indicating that neutrophil CD177 expression can increase significantly in certain clinical conditions.

Adult↗

Alloimmune neonatal neutropenia linked to anti-HNA-4a.

This is a novel case report of alloimmune neonatal neutropenia (ANN) linked to the neutrophil antibody anti-HNA-4a (MART). Since its discovery, the HNA-4a antigen has never been associated with any clinical neutropenia. A first-born neonate with respiratory distress was found to be severely neutropenic, because of ANN. The broad reactivity of the antibody together with its capture by CD11b and CD18 in monoclonal antibody immobilization of granulocyte antigen test suggested HNA-4a specificity. DNA sequencing confirmed that the father is HNA-4a-positive and that the mother is HNA-4a-negative, supporting the diagnosis of ANN linked to MART.

Antigen-Antibody Reactions↗

Severe neonatal neutropenia due to anti-human leucocyte antigen B49 alloimmunization only: a case report.

Alloimmune neonatal neutropenia (ANN) is a rare but potentially life-threatening disorder of neonates. Demonstration of alloantibodies against granulocyte-specific antigens shared by neonatal and paternal granulocytes in the maternal serum is essential in the diagnosis of ANN. In contrast to granulocyte-specific alloantibodies, the significance of human leucocyte antigen (HLA) class I antibodies for ANN is still a matter of debate. We report on a case of severe isolated and prolonged neutropenia due to anti-HLA B49 alloimmunization only. Immediately after birth, severe, isolated neutropenia was observed and lasted for up to 2 months. Results of serologic testing showed only anti-HLA B49 antibodies in the maternal and neonate's sera. HLA typing showed HLA class I (B49) incompatibility between the mother and the child. Granulocyte-specific antibodies were not detected. Adsorption of the maternal serum with HLA B49-bearing platelets removed serum reactivity with paternal neutrophils. Our results support the idea that certain HLA class I antibodies can induce ANN.

Adult↗

TRALI due to granulocyte-agglutinating human neutrophil antigen-3a (5b) alloantibodies in donor plasma: a report of 2 fatalities.

BACKGROUND: TRALI is usually an immunologic reaction to WBC antibodies in infused plasma and ranks second only to ABO mismatch as a cause of transfusion-associated death. Implicated donors are usually multiparous women (>/=3 pregnancies). STUDY DESIGN AND METHODS: Two fatal cases of TRALI were evaluated by reviewing clinical and laboratory findings and characterizing alloantibodies present in donor plasma. Investigation for WBC antibodies was by lymphocytotoxicity (LCT), FlowPRA (FlowPRA, One Lambda, Inc.) and granulocyte immunofluorescence and agglutination assays. Patient 1 was a 62-year-old man with chronic T-cell lymphocytic leukemia, and Patient 2 was a 54-year-old woman undergoing a cadaveric kidney transplant. Both patients developed acute respiratory distress and hypotension during (Patient 1) and approximately 30 minutes after (Patient 2) transfusion. Fulminant pulmonary edema ensued in both cases necessitating mechanical ventilation and both patients died within 24 hours of the onset of respiratory complications. RESULTS: The donors of the implicated blood components were women with a history of two pregnancies but no blood transfusions. Weak apparently panreactive granulocyte antibodies were detected with flow cytometry. However, in the granulocyte agglutination test, strong antibodies specific for human neutrophil antigen (HNA)-3a (5b) were identified in both donors. CONCLUSION: It is concluded that female blood donors with only two previous pregnancies can form clinically important granulocyte-reactive alloantibodies leading to fatal TRALI reactions in recipients. The sometimes devastating consequences of TRALI should prompt the development of strategies to prevent or reduce its incidence. Further research is warranted to investigate recipient and donor factors responsible for TRALI, including whether 5b (HNA-3a) alloantibodies are especially prone to cause severe reactions, and to better characterize the HNA-3a (5b) antigen, particularly at the molecular level.

Agglutination↗

Tolerance of granulocyte donors towards granulocyte colony-stimulating factor stimulation and of patients towards granulocyte transfusions: results of a multicentre study.

Data of 507 granulocyte donations from 183 donors were evaluated. No severe granulocyte colony-stimulating factor (G-CSF)-related side-effects were observed. Three donors complained of severe itching following infusion of hydroxyethyl starch (HES). A high proportion (85%) of the donors stated that they would donate granulocytes again. The mean granulocyte yield was 4.3 x 10(10). High-molecular-weight HES resulted in a significantly higher yield compared with low-molecular-weight HES. Mild, but no severe, adverse transfusion reactions were observed in 16% of the recipients. A leucocyte alloimmunization rate of 24% was found. G-CSF stimulation and transfusion of G-CSF-mobilized granulocytes were well tolerated by donors and recipients, respectively.

Adolescent↗

Quantitative determination of Fcgamma receptor genes by means of fluorescence-based real-time polymerase chain reaction.

The granulocyte antigens HNA-1a, -1b and -1c reside on the FcgammaIIIb receptor, which is exclusively expressed on neutrophils. They are involved in autoimmune and alloimmune neutropenias as well as in severe transfusion reactions. Recent family studies show the HNA-1c antigen to be inheritably linked to HNA-1a, resulting in individuals carrying three genes. Using sequence-specific primers, the HNA antigens can be discerned in a polymerase chain reaction (PCR), but not the number of coding FCGR3B genes present in each individual. Therefore a real-time kinetic PCR method using the LightCycler technique was established to ascertain the amount of FCGR3B genes in each individual. For this purpose, the FCGR3B genes of four HNA-1a,-1b,-1c (+), one HNA-1b,1c (+) and one HNA-1b (+) individual were quantified. In addition, two families, in which the mother was FCGR3B deficient, were analyzed. Quantification showed two of the four HNA-1a,-1b and-1c (+) individuals to have three genes and the other two to have only two genes. The HNA-1b,-1c (+) individual had also only two genes. As expected, the HNA-1b donor was typed for two genes. No FCGR3B genes could be detected in the FCGR3B-deficient mothers of either family; their husbands however, carried two FCGR3B genes. Accordingly, quantitative PCR showed the offspring of both families to have only one FCGR3B gene. Quantitative PCR with the Light Cycler has been revealed to be a fast and reliable method for the determination of FCGR3B genes present. FCGR3B quantification confirms the idea of the HNA-1c antigen to be inherited not only linked to HNA-1a, but also to be passed down on its own.

DNA Mutational Analysis↗

Granulocyte immunology.

Antibodies directed against antigens on the granulocyte (neutrophil) membrane can cause a variety of disorders including neonatal immune neutropenia, immune neutropenia after bone marrow transplantation, autoimmune neutropenia, and drug-induced immune neutropenia. Since granulocyte alloantibodies can lead to severe pulmonary transfusion reactions (TRALI), febrile transfusion reactions and refractoriness to granulocyte transfusions, they also play an important part in blood transfusion. The implicated human neutrophil alloantigens (HNA) have been renamed in the recently introduced HNA nomenclature which is based on the antigen's glycoprotein location. The Fc gamma Receptor IIIb (CD16, HNA-1) and the NB1 glycoprotein (CD177, HNA-2) represent the major immunogenic molecules of the neutrophil membrane. They bear the clinically most important antigens HNA-1a,-1b,-1c (NA1, NA2, SH) and HNA-2a (NB1), respectively. For the detection of granulocyte antibodies, a combination of immunofluorescence and agglutination tests together with a panel of freshly isolated, typed test neutrophils has been shown to represent the best means of detection. The introduction of the glycoprotein-specific assay "MAIGA" has improved alloantibody identification considerably. To facilitate and improve neutrophil typing, PCR-SSP techniques have been established for HNA-1a,-1b, and -1c genotyping.

ABO Blood-Group System↗

Molecular basis of the neutrophil glycoprotein NB1 (CD177) involved in the pathogenesis of immune neutropenias and transfusion reactions.

The human granulocyte alloantigen NB1, recently clustered as CD177, is heterogenously expressed on neutrophils of 88-97% of healthy individuals. Since its molecular nature has remained unknown, we isolated NB1 glycoprotein from granulocyte lysate by immunoaffinity chromatography. MALDI-TOF mass spectrometry identified a 50,556 Da glycoprotein which was reduced to 43,069 Da after removal of N-linked carbohydrates. Following N-terminal amino acid sequencing and NB1-specific primer construction, rapid amplification of cDNA ends PCR yielded a 1,614-bp cDNA for NB1. COS-7 cells transfected with the cDNA expressed immunoreactive NB1 glycoprotein. A 1,311-bp sequence was identified to be the entire coding region. The 5' and 3' untranslated regions consist of 27 bp and 276 bp, respectively. The open reading frame codes for 437 amino acids of which the first 21 form the signal peptide. The remaining 416 residues form a N-terminal extracellular protein with two cysteine-rich domains, three N-linked glycosylation sites and short transmembrane and cytoplasmic segments including a glycosyl-phosphatidylinositol attachment (omega) site. Database searches revealed homology to Ly-6 (uPAR) domain, suggesting that NB1 belongs to urokinase plasminogen activator receptor/CD59/Ly-6 snake toxin superfamily.

Amino Acid Sequence↗

[The TRALI syndrome--a life-threatening transfusion reaction].

Transfusion related acute lung injury (TRALI) is a serious complication of blood transfusion, characterized by non-cardiogenic lung oedema. We describe a case of TRALI due to granulocyte-specific antibodies. The 58-year-old patient received 2 units of fresh frozen plasma following colon surgery and within 30 min the patient developed an acute respiratory distress syndrome. Granulocyte-specific antibodies were found in one of the transfused plasma of a female blood donor who most likely became immunized against granulocyte alloantigens during her three pregnancies.

Acute Disease↗

Molecular nature of granulocyte antigens.

Granulocyte (neutrophil) antibodies can cause febrile and pulmonary (TRALI) transfusion reactions as well as immune neutropenias. In the last decade enormous efforts have been made to characterize the implicated alloantigens. The NA1, NA2, and SH antigens could be identified as polymorphic forms of the neutrophil Fc gammaReceptor IIIb encoded by three alleles. The antigens MART and OND have been located on the leucocyte adhesion molecules (beta2 integrins) and found to be caused by single nucleotide mutations in the alphaM (CD11b) and alphaL (CD11a) subunits. We have succeeded in throwing light on the primary structure of the NB1 antigen, which has recently been clustered as CD177. Based on these findings, the Granulocyte Antigen Working Party of the ISBT introduced in 1998 a new nomenclature for human neutrophil alloantigens (HNA nomenclature) based on the antigen's glycoprotein location. Elucidation of the molecular nature of granulocyte antigens now allows antigen identification by glycoprotein-specific immunoassays and genotyping by DNA techniques. Thus, considerable progress has been made in the characterization of granulocyte antigens. Further studies will improve our diagnostic tools and facilitate the prevention and management of transfusion reactions and immune neutropenias.

Amino Acid Substitution↗

Workshop report on the genotyping of blood cell alloantigens.

The immunization against alloantigens present on platelets, granulocytes and red blood cells (RBCs) is responsible for various clinical syndromes. Since the molecular basis of these antigens has become clear during the last decade, genotyping is nowadays used in several laboratories. However, many DNA-based techniques still have to be evaluated. We therefore organized a workshop on the genotyping of the most relevant alloantigens on platelets and granulocytes as well as on selected RBC alleles. DNA was isolated from peripheral blood lymphocytes or from B-lymphoblastoid cell lines (B-LCL). We distributed samples for the identification of platelet (n = 7), granulocyte (n = 6) and RBC (n = 4) polymorphisms, respectively. There were 33 institutions in Germany, Austria and Switzerland, which participated in at least one part of the workshop. Twenty-four laboratories reported results on HPA-1, and 23 laboratories on HPA-2, -3, and -5 typing. In addition, five laboratories typed for HPA-4 and -6. The HNA-1a/b (NA1/NA2) alleles were identified by eight laboratories, one of which also typed for HNA-1c (SH). The most frequent genes of the ABO (A1, B, O) and Rh (D, C, c, E, e) systems were typed by 12 participating laboratories, and an additional four laboratories restricted their RBC typing to the RHD gene. The typing technique mainly used for all three cell lineages was the polymerase chain reaction with sequence-specific primers. Other techniques were restriction fragment length analysis, oligonucleotide ligation assay, enzyme-linked mini-sequence assay or direct sequence analysis. The following typing errors were observed: HPA: 15/1442 (1.0%), HNA: 4/108 (3.7%), ABO: 5/96 (5.2%) RH 1/320 (0.3%). Our workshop demonstrated the existence of a number of reliable techniques for the genotyping of blood cell alloantigens and a high standard in the participating laboratories. In addition, we could show the usefulness of B-LCL as a source of reference DNA. However, the 5.2% rate of mistyping in the ABO system demonstrated that further efforts are needed to improve the precision of the genotyping techniques. Future workshops will have to challenge methods and participants with rare variants of RBC genes to guarantee reliable genotyping, e.g. in prenatal diagnosis of fetomaternal incompatibility.

ABO Blood-Group System↗

Phase I/II trial of neutrophil transfusions from donors stimulated with G-CSF and dexamethasone for treatment of patients with infections in hematopoietic stem cell transplantation.

We examined the feasibility of a community blood bank granulocyte transfusion program utilizing community donors stimulated with a single-dose regimen of subcutaneous granulocyte colony-stimulating factor (G-CSF) plus oral dexamethasone. The recipients of these transfusions were neutropenic stem cell transplantation patients with severe bacterial or fungal infection. Nineteen patients received 165 transfusions (mean 8.6 transfusions/patient, range 1-25). Community donors provided 94% of the transfusions; relatives accounted for only 6% of the transfusions. Sixty percent of the community donors initially contacted agreed to participate, and 98% of these individuals indicated willingness to participate again. Transfusion of 81.9 +/- 2.3 x 10(9) neutrophils (mean +/- SD) resulted in a mean 1-hour posttransfusion neutrophil increment of 2. 6 +/- 2.6 x 10(3)/microL and restored the peripheral neutrophil count to the normal range in 17 of the 19 patients. The buccal neutrophil response, a measure of the capacity of neutrophils to migrate to tissue sites in vivo, was restored to normal in most patients following the transfusion. Chills, fever, and arterial oxygen desaturation of >/= 3% occurred in 7% of the transfusions, but these changes were not sufficient to limit therapy. Infection resolved in 8 of 11 patients with invasive bacterial infections or candidemia. These studies indicate that transfusion of neutrophils from donors stimulated with G-CSF plus dexamethasone can restore a severely neutropenic patient's blood neutrophil supply and neutrophil inflammation response. Further studies are needed to evaluate the clinical efficacy of this therapy.

Administration, Oral↗

HNA-1a, HNA-1b, and HNA-1c (NA1, NA2, SH) frequencies in African and American Blacks and in Chinese.

The granulocyte antigens HNA-1a, -1b, and -1c (formerly named NA1, NA2 and SH) which reside on the neutrophil FcgammaReceptor IIIb (FcgammaRIIIb) play a major role in immune neutropenias and pulmonary transfusion reactions. In an attempt to shed some light on the origin and history of these antigens we typed the DNA of Blacks from South Africa (n=99), and Ghana (n=27), of 56 African Americans, and of 138 Chinese from Taiwan for HNA-1a,-1b, and -1c antigens using polymerase chain reaction with sequence-specific primers (PCR-SSP). In African and American Blacks, the HNA-1b antigen was more frequent than HNA-1a (77 vs. 67% and 77 vs. 59%, respectively). In contrast, in Chinese HNA-1a was more frequent than HNA-1b (91 vs. 54%). We observed 3 individuals with FcgammaRIIIB deficiency among the 126 tested African Blacks indicating a higher frequency of FcgammaRIIIB deficiency in Blacks than the reported 0.1% in Europeans. In addition, the frequency of HNA-1c in African and American Blacks (38 and 23%, respectively) was higher than the reported 5% in Europeans. Among the 57 HNA-1c (+) Blacks, all were HNA-1b (+) but only 26 were HNA-1a (+) supporting the idea that the HNA-1c antigen is the result of an additional point mutation in the allele coding for HNA-1b. Recently, HNA-1a, -1b, and -1c (+) Europeans have been reported to have three distinct FcgammaRIIIB genes. Among 26 Blacks who had been typed HNA-1a,b,c (+) by PCR-SSP we identified only 7 having three FcgammaRIIIB genes by DNA sequencing. When we sequenced the DNA of 6 HNA-1a,b,c (+) Europeans we found 4 of the individuals had three FcyRIIIB genes. Therefore, we assume that in Africa the point mutation occurred first in the HNA-1b allele resulting in the HNA-1c allele and the FcgammaRIIIB gene duplication took place later.

Asian People↗

Neutropenia and anaemia due to carbimazole-dependent antibodies.

Carbimazole-dependent antibodies to erythrocytes were detected in the sera of three anaemic patients who had been treated with carbimazole for hyperthyroidism. By the use of Rhnull-typed erythrocytes, we could show that some of these were directed against the proteins of the Rh complex. Carbimazole-dependent antibodies eluted from erythrocytes showed no binding to other blood cells. One patient also presented with neutropenia and mild thrombocytopenia. Additional carbimazole-dependent antibodies against the neutrophil-specific Fcgamma receptor IIIb (FcgammaRIIIb, CD16b) and the broadly expressed platelet endothelial cell adhesion molecule 1 (PECAM-1; CD31) were detected in this patient's serum. Surprisingly, the PECAM-1-reactive drug-dependent antibodies were also detectable in the sera of the other two patients with normal leucocyte and platelet counts. We assume that carbimazole can induce cell lineage-specific drug-dependent antibodies that cause cytopenia and also drug-dependent antibodies against the broadly expressed PECAM-1 molecule that may cause mild but not severe cytopenia.

Aged↗

B-lymphoblastoid cell lines as a source of reference DNA for human platelet and neutrophil antigen genotyping.

BACKGROUND: Human platelet and neutrophil antigens (HPAs, HNAs) are targets for platelet or granulocyte antibodies causing immune thrombocytopenia or neutropenia, respectively. Currently, genotyping is replacing phenotyping as the preferred method of diagnosis of immune cytopenia. To establish a reliable genotyping analysis, however, the availability as reference DNA of genomic DNA from persons of known genotype is essential. STUDY DESIGN AND METHODS: By the use of Epstein-Barr virus transformation, panels of B-lympho-blastoid cell lines (B-LCLs) from HPA- and HNA-phenotyped individuals were developed. Genomic DNA was isolated from these cell lines and tested as reference DNA for genotyping of persons for HPAs and HNAs. RESULTS: DNA derived from these B-LCLs was typed by polymerase chain reaction-restriction fragment length polymorphism and -sequence-specific primers. The results were in accordance with the genotyping from peripheral blood cells. These results were confirmed by 24 laboratories in Germany in a blind study. CONCLUSION: The inexhaustible source of reference DNA derived from B-LCLs allowed the evaluation of reliable HPA and HNA genotyping for quality control purposes. It should facilitate the development of DNA typing in blood centers and clinical laboratories.

Antigens↗