Identification of the novel HLA-A*240215 allele by haplotype-specific sequencing

Here, we report on a novel allele human leukocyte antigen (HLA)-A*240215. This allele differs from HLA-A*240201 by a synonymous nucleotide exchange at nucleotide 255 in exon 2.

Immune tolerance induction in patients with IgA anaphylactoid reactions following long-term intravenous IgG treatment

To date, there is very little information regarding the pathomechanism of IgA anaphylactoid reactions and the management of affected patients. Five adult patients with common variable immunodeficiency (CVID) and a history of anaphylactic reactions due to the administration of immunoglobulin preparations were studied. The activity of anti-IgA was determined by the gel agglutination technique using IgA-coated beads. Antibodies to IgA were detected in the serum of all five patients. Initially, IgA 'depleted' intravenous (i.v.) IgG preparations were infused carefully into the patients until the activity of anti-IgA was decreased significantly or became undetectable. Subsequently, unselected i.v. IgG preparations were infused, and the activity of anti-IgA was abolished in all cases. Intravenous IgG long-term administration results in tolerance induction in patients with IgA anaphylactoid reactions. This tolerance appears to be related to antibody blockage in the circulation and an inhibition of antibody production. Most importantly, IgA appears to play an important role in the treatment of CVID. Patients with IgA anaphylactoid reactions can be treated safely with IgA containing i.v. IgG preparations following tolerance induction.

Application of the particle gel agglutination assay in the typing of single human leucocyte antigens

We describe a simple and rapid particle gel agglutination assay (PaGIA) for typing of the human leucocyte antigens (HLA) HLA-A2, HLA-B7 and HLA-B27. Superparamagnetic streptavidin particles were coated with biotinylated monoclonal antibodies (MoAbs) to HLA-A2, HLA-B7 and HLA-B27. Anticoagulated whole blood samples from healthy blood donors (n = 118) with known HLA patterns were incubated with MoAb-coated particles, transferred into a standard ID-gel card, and subsequently centrifuged. Samples were evaluated macroscopically, with antigen-positive samples resulting in a visible agglutination reaction. A clear distinction could be made between all positive and negative samples tested. Fifty-seven samples were found to be positive for HLA-A2 (48%), 26 samples for HLA-B7 (22%) and 5 samples for HLA-B27 (4%).

Compatibility and stability of tramadol and dexamethasone in solution and its use in terminally ill patients

BACKGROUND

Delivery of drug admixtures by continuous subcutaneous infusion is common practice in palliative medicine, but analytical confirmation of their compatibility and stability is not always available.

OBJECTIVE

To study the compatibility and stability of tramadol hydrochloride and dexamethasone sodium phosphate combined in solution and to report on its use in terminally ill patients.

METHOD

Twelve different solutions containing tramadol hydrochloride (8.33-33.33 mg/mL) and dexamethasone sodium phosphate (0.33-3.33 mg/mL) were prepared in saline and stored in polypropylene syringes for 5 days (25 degrees C). Analysis was performed on days 1, 3 and 5 days with simultaneous determination by HPLC. pH was measured at 0 and 5 days. Clinical performance was assessed retrospectively in six terminal-ill oncology patients.

RESULTS

Maximum losses of 7% and 6% were observed for tramadol and dexamethasone. Pain was completely controlled in four patients. Local tolerance resulted in haematoma in three patients, which resolved by switching to a butterfly insertion site.

CONCLUSION

Tramadol hydrochloride (100-400 mg/day) and dexamethasone sodium phosphate (4-40 mg/day) are stable for at least 5 days when combined in saline and stored at 25 degrees C. These results are only valid for the type of syringes and the specific commercial preparations tested.

Identification of a novel HLA-DQB1 allele, HLA-DQB1*0632

A novel human leukocyte antigen-DQ allele, DQB1*0632, was identified in a 68-year-old bone marrow transplantation candidate. DQB1*0632 differs from DQB1*0603 by one nucleotide change in exon 2 resulting in the amino acid exchange Gly --> Arg.

A rapid gel agglutination test for the determination of fetomaternal haemorrhage

Determination of fetomaternal haemorrhage (FMH) remains an area of difficulty. In most cases, prophylactic Rh immunoglobulin is usually administered to affected women without testing for foetal red blood cells (RBC). Here, we describe a new particle gel immunoassay (PaGIA) for the determination FMH (FMH-PaGIA). Superparamagnetic particles were coated with monoclonal anti-D and mixed with ethylenediaminetetraacetic acid-anticoagulated blood samples from D-negative pregnant women. The particles were isolated using a magnetic particle concentrator and then placed into the reaction chamber of a gel card. Agglutinated particles on top or dispersed through the gel matrix indicated the presence of D-positive cells. After the test was adapted to detect >or=0.3% D-positive RBC, randomly selected postpartum samples from 208 women were analysed in parallel with the Kleihauer-Betke test (KBT). In addition, all discrepancies were further analysed by flow cytometry. A total of 203 of the 208 postpartum samples were negative in both tests. One sample reacted positive with both assays. Two samples were strongly positive in the new FMH-PaGIA, but negative in the KBT. A serological re-examination revealed that both women were D positive. The KBT gave a false-positive result in two cases because of hereditary persistence of haemoglobin F. The new test is specific, easy to perform and can be done at any time in all laboratories.

Application of the particle gel agglutination system as a new check gel assay for PCR products

In this study, we describe a simple and rapid agglutination test for the detection of PCR products prior to the application of specific hybridization by sequence-specific oligonucleotide typing. This test is based on the particle gel agglutination immunoassay, incorporating biotinylated primers and streptavidin particles. Visually detectable agglutination was only observed in samples which contained the specific amplification products. The results obtained by the new test were in accordance with those obtained by standard gel electrophoresis in all cases that have been tested to date.

Optimum storage conditions for cord blood-derived hematopoietic progenitor cells prior to isolation

Optimum storage conditions of cord blood-derived hematopoietic progenitor cells before isolation remain unknown. We therefore evaluated CD34+ cells isolated from cord blood units (n=57) within 1 h after collection and following storage for 24, 48 and 72 h at either room temperature (RT) or 4 degrees C. Isolated CD34+ cells were analyzed for their cell count, immunophenotype, apoptosis rate, clonogenicity and transmigration capacity in response to stroma-derived factor 1alpha using direct-paired comparisons (n=27). CD34+, CD133+ and CD45+ positivity after isolation remained the same under all conditions. After 24 h, CD34+ cell counts and numbers of CFU-GM colonies dropped regardless of the storage temperature. After 48 h, the number of CD34+ cells increased compared to 24 h, if the cord blood had been stored at RT resulting in almost three times more CD34+ cells than at 4 degrees C. These cells had a lower early apoptosis rate and formed four times more BFU-E than those stored at 4 degrees C with equivalent plating efficiencies. CD34+ cells kept at RT for 48 h had the highest transmigration capacities, which paralleled an increased CXCR-4 expression. Cord blood should be stored at RT before CD34+ isolation and a storage time for 48 h should be preferred to 24 h.

[Preoperative identification of patients with impaired (primary) haemostasis. A practical concept]

The findings of a large prospective study designed to identify primary and/or secondary haemostatic disorders before surgical interventions are presented. A total of 5649 unselected adult patients were enrolled to identify impaired haemostasis before surgical interventions. Each patient was asked to answer a standardized questionnaire concerning bleeding history. Activated partial thromboplastin time (aPTT), prothrombin time (PT), and platelet counts (PC) including PFA-100 (platelet function analyzer): collagen-epinephrine (C/E), and collagen-ADP (C/ADP) were routinely done in all patients. Additional tests, bleeding time (BT), von Willebrand factor (VWF:Ag, VWF:Rcof) and a further haemostaseological diagnostic was performed only in patients with a positive bleeding history and/or evidence of impaired haemostasis; e.g., drug ingestion. The bleeding history was negative in 5021 patients (88.8%) but positive in the remaining 628 (11.2%). Impaired haemostasis could be verified only in 256 (40.8%) of these patients. The vast majority was identified with PFA-100: C/E (n = 250; 97.7%). The sensitivity of the PFA-100: collagen-epinephrine was the highest (90.8%) in comparison to the other screening tests (BT, aPTT, PT, VWF : Ag). The positive predictive value (to detection of impaired haemostasis) of the PFA-100: collagen-epinephrine with the standardized questionnaire was high (82%), but the negative predictive value was higher (93%). The use of a standardized questionnaire and, if indicated, the PFA-100: C/E and/or other specific tests not only ensure the detection of impaired haemostasis in almost every case but also a significant reduction of the costs. Based on these data, national regards are formulated or under construction.

A novel antigen-specific capture assay for the detection of platelet antibodies and HPA-1a phenotyping

BACKGROUND AND OBJECTIVES

The antigen-specific assays currently used for the laboratory investigation of platelet antibodies and antigens are technically complex and cannot be used in most routine laboratories. Here, we describe a simple antigen-specific capture assay (ASCA) for the detection of serum platelet antibodies and for human platelet antigen-1a (HPA-1a) phenotyping.

MATERIALS AND METHODS

For the detection of platelet antibodies, platelets from healthy blood donors were incubated with biotinylated monoclonal antibodies to platelet glycoprotein complexes (GP), then solubilized and mixed with superparamagnetic streptavidin particles. Serum samples from patients with autoimmune thrombocytopenia (n = 39), from patients with platelet alloantibodies (6 HPA-1a, 1 HPA-2b, 1 HPA-3a, 6 HPA-5b), and from healthy blood donors (n = 70), were tested. All serum samples from the patients were investigated in parallel by the indirect monoclonal antibody-specific immobilization of platelet antigen assay (MAIPA). For HPA-1a phenotyping, superparamagnetic particles were coated with a monoclonal antibody to HPA-1a and mixed with diluted whole blood samples from healthy blood donors (n = 139), who had previously been genotyped for platelet alloantigens. Results The indirect MAIPA detected autoantibodies in 18%, and the direct MAIPA in 50% of patients tested. In contrast, the new ASCA demonstrated positive results in 77% of patients. All tested alloantibodies reacted positive by the ASCA, and all serum samples from healthy blood donors were negative. The results of HPA-1a phenotyping were in concordance with those of genotyping in all cases.

CONCLUSION

In our opinion, the ASCA is easy to perform and much more sensitive than the currently available antigen-specific assays for the detection of platelet antibodies.

CD47 is expressed at normal levels in patients with autoimmune haemolytic anaemia and/or immune thrombocytopenia

CD47 deficiency results in lethal autoimmune haemolytic anaemia (AIHA) and mild spontaneous thrombocytopenia in non-obese diabetic mice. It is unknown whether CD47 has an impact on AIHA of the warm type or autoimmune thrombocytopenia (ITP) in humans. Healthy blood donors (n= 11), patients with AIHA (n= 13), patients with ITP (n= 18) and one patient with Rh(null) phenotype were investigated. CD47 expression on red blood cells (RBC), platelets, granulocytes and lymphocytes and in plasma was determined by quantitative flow cytometry. All types of blood cells studied were found to carry CD47. Although CD47 expression on Rh(null) RBCs was decreased, there was no significant difference between CD47 expression on RBCs of healthy blood donors and on those of patients with AIHA or ITP. Similarly, CD47 was detectable in the plasma of the studied subjects. No evidence for a pathogenetic role of CD47 in autoimmune haemolysis or thrombocytopenia in humans could be demonstrated.

Diagnosis of gonococcal infection in high risk women using a rapid test

OBJECTIVE

To assess the performance and acceptability for patients and health care workers of the NGThermo Biostar (GC OIA) to diagnose gonococcal infection compared with culture using modified Thayer Martin medium.

METHODS

This study involved 326 high-risk women presenting with vaginal discharge or referral by sexual partner with urethral discharge at a sexually transmitted infections (STI) clinic in Manaus, Brazil. Endocervical swabs collected from the women were tested with both the NG Biostar and modified Thayer Martin culture as the reference standard test. Clinic staff were trained to perform the NG Biostar on site and the culture was performed in the laboratory of the clinic.

RESULTS

The prevalence of gonococcal infection as measured by the reference standard was 15% (50/326) overall. Among asymptomatic participants, the prevalence of infection was 17.7% (25/141) and among symptomatic women it was 13.5% (25/185) (p = 0.3). Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) for the NG Biostar test, with 95% confidence intervals (CI), were 60% (46.4% to 73.6%), 89.9% (86.2% to 93.6%), 55.6% (42.4% to 68.8%), and 92.6% (89.5% to 95.7%), respectively; 98.8% of study participants were willing to wait approximately 1 hour in the clinic for test results.

CONCLUSION

Syndromic management protocols for treatment of STI in developing countries require refinement because, as currently described, they lead to over-treatment of cervical infection. A rapid test done during patients' initial presentation and leading to immediate treatment if positive would help improve the accuracy of diagnosis and could also be used to screen asymptomatic women. Even though the NG Biostar had a low sensitivity and PPV, which is less than ideal, it could still improve the rates of treatment over the gold standard test that requires return visits for patients to receive results and to benefit from treatment. Cost-effectiveness studies using rapid point-of-care tests for Neisseria gonorrhoeae infection compared to the syndromic approach should be carried out to assess their value in STI diagnosis and treatment in developing nations.

Replacement of intravenous administration of anti-D by subcutaneous administration in patients with autoimmune thrombocytopenia

Intravenous (IV) administration of anti-D in patients with autoimmune thrombocytopenia (AITP) may result in severe hemolysis and even death. Over a 3-year period, we gave anti-D only subcutaneously (SC), and none of our patients have developed any acute adverse reaction. Most importantly, SC delivery of anti-D produces largely the same beneficial effect as obtained by IV anti-D. We recommend replacement of IV administration of anti-D by SC administration in AITP.

A simple and practical agglutination assay for human leucocyte antigen-B27 typing

BACKGROUND AND OBJECTIVES

The human leucocyte antigen (HLA) B27 is the most frequently typed single antigen that is associated with diseases. Here, we describe a simple and rapid particle agglutination assay (PaGIA) for HLA-B27 typing.

MATERIALS AND METHODS

Superparamagnetic particles were coated with a monoclonal antibody to HLA-B27 and subsequently used for testing. Anticoagulated whole-blood samples were obtained from healthy blood donors (n = 194) with known HLA patterns and from patients (n = 51) who had been typed positive for HLA-B27 by flow cytometry.

RESULTS

The particles agglutinated only after incubation with HLA-27-positive blood samples, using the ID-microtyping system. Positive reactions were clearly distinguishable from negative reactions in all samples tested. Flow cytometric HLA-B27 typing revealed an indeterminate result in one patient.

CONCLUSIONS

The new HLA-B27 PaGIA is suitable for rapid typing of HLA-B27. The assay is simple and easy to perform, and can be implemented in any routine laboratory.

ELISA methods detect HLA antibodies with variable sensitivity

The accuracy of human leukocyte antigen (HLA) antibody screening results is dependent on the technique employed. In this study, a total of 612 serum samples from patients awaiting kidney transplantation were tested by two different enzyme-linked immunosorbent assay (ELISA) methods: LAT-M(R) (One Lambda/BMT) and AbScreen(R) (Biotest). The results of these assays were identical for HLA class I and II antibodies in 524 cases (85.6%), and discrepant in the remaining 88 cases (42 class I, 24 class II, 22 class I and II). More specifically, class I results were in agreement in 26 positive and 522 negative cases and in disagreement in 64 cases. Class II results were the same in 50 positive and 516 negative cases and different in 46 cases. Retesting the samples using LAT 1288 (One Lambda/BMT) and considering previous HLA antibody test results and the history of immunising events, the sensitivity and specificity, respectively, of the two methods were determined as follows: class I: 89.6% and 97.5% (LAT-M) vs. 70.6% and 96.8% (AbScreen), class II: 96.5% and 98.4% (LAT-M) vs. 88.3% and 95.5% (AbScreen). These results indicate that a single ELISA does not invariably prove or exclude the presence of HLA antibodies, and that additional testing is required in some cases.

The effect of the diameter of metal-on-metal bearings on systemic exposure to cobalt and chromium

The recent resurgence in the use of metal-on-metal bearings has led to fresh concerns over metal wear and elevated systemic levels of metal ions.

In order to establish if bearing diameter influences the release of metal ions, we compared the whole blood levels of cobalt and chromium (at one year) and the urinary cobalt and chromium output (at one to three and four to six years) following either a 50 mm or 54 mm Birmingham hip resurfacing or a 28 mm Metasul total hip replacement. The whole blood concentrations and daily output of cobalt and chromium in these time periods for both bearings were in the same range and without significant difference.

Detection of a new weak A blood-group allele (Aw11)

BACKGROUND AND OBJECTIVES

Weak ABO variants may escape tests using unlicensed sera.

MATERIALS AND METHODS

Prior to transfusion, ABO grouping was performed using an automated system and in-house diluted sera, and manual and bedside test techniques. Genotyping and sequencing were performed using standard methods.

RESULTS

Initially, the red blood cells (RBC) of the first-time blood donor were typed as B, but pretransfusion testing carried out using the bedside test indicated the presence of an additional A phenotype. Serological re-examination confirmed the bedside test results, and the allele in question was identified, by genotyping, as a new weak A variant (Aw11).

CONCLUSIONS

The use of CE-marked and licensed antisera is recommended to avoid ABO mistyping.

Disclosure Regulation and Accounting Education in the UK: Moving Towards Corporate Accountability 252 and Transparency

This paper was motivated by the current debate over the voluntary approach to environmental disclosures in corporate annual reports and assesses the effectiveness of the current policy of voluntarism in the UK. A brief review of the relevant theories, which explain why managers might choose to voluntarily provide environmental responsibility information to parties outside the organisation, is presented. With this background, the paper then questions whether the UK government’s faith in voluntarism and the pursuit of best practice will be enough to generate any real change in current environmental reporting practices. We argue that voluntarism is not effective and that there is an urgent need to introduce strict governmental regulations on the information that must be disclosed and the form in which it should be presented in corporate annual reports as have been established in several other countries. In addition, further consideration is needed to achieve reforms in academic accounting education in order to improve corporate accountability and transparency in corporate annual reports. Organisations need to respond to the growing demands for corporate social and environmental responsibility and this will be possible with the support of an accounting profession that takes a more proactive approach to engaging with stakeholders. For this to happen, we need to rethink the focus of accounting and business education. We must move away from the dominant model, which treats accountancy as a set of techniques, towards a more holistic approach which recognises the social and environmental impacts of organisational activity.

Antibodies against protein Z and fetal loss: current perspectives

Protein Z (PZ) is a vitamin K-dependent plasma protein that serves as a cofactor for the inactivation of factor Xa. A number of investigators found low PZ levels in patients with haemorrhagic as well as thromboembolic diseases, although there is no clear evidence of a pathogenic link between PZ deficiency and these clinical disorders. Nevertheless, low PZ levels have been found in association with early fetal losses, especially those occurring before the 15th week of gestation and in patients with detectable antiphospholipid and anti-PZ antibodies. The current diagnostic relevance and therapeutic consequences of these parameters will be discussed.

Human platelet antigen genotyping by using sequence-specific primers and the particle gel agglutination assay

BACKGROUND AND OBJECTIVES

Polymerase chain reaction using sequence-specific primers (PCR-SSP) is currently the most widely used technique for human platelet antigen (HPA) genotyping. Here, we describe a novel particle gel-agglutination technique for simplified visualization of the amplified products.

MATERIALS AND METHODS

Biotinylated primers were used to amplify HPA-1, -2, -3, -4, -5, -6, and -15, and the PCR products were incubated with streptavidin particles. Fluorescein isothiocyanate (FITC)-labelled primers [amplifying a fragment of the human growth hormone (HGH) gene] and anti-FITC-coated particles were used as internal controls. Agglutination of the particles in or on top of the gel indicated specific amplification. A total of 100 samples from blood donors was tested by using this new technique and a standard PCR-SSP protocol.

RESULTS

The use of biotinylated sequence-specific primers resulted in PCR products that agglutinated streptavidin particles, and the FITC-labelled HGH primers led to agglutination of anti-FITC-coated particles. Negative reactions were clearly distinguishable from positive reactions. The results of the particle gel agglutination method were in concordance with those of the electrophoretic visualization in all cases tested.

CONCLUSIONS

The new particle agglutination method is reliable and easy to use.

Tumor necrosis factor alpha enhances the adenoviral transduction of CD34+ hematopoietic progenitor cells

The purpose of this study was to improve the transduction efficiency of adenoviral vectors (Ad) in human CD34+ hematopoietic progenitor cells. CD34+ cells from cord blood or mobilized peripheral blood were incubated with tumor necrosis factor-alpha (TNF-alpha). After removal of free TNF-alpha, the cells were infected with an Ad encoding green fluorescent protein (GFP). One day later, viable cells were counted and analyzed for GFP and CD34 by flow cytometry. To visualize vectoral trafficking, CD34+ cells were incubated with fluorophore-conjugated Ad. Plating efficiencies of hematopoietic progenitors before and after transduction were evaluated by methylcellulose assays. Pretreatment with TNF-alpha increased the transduction efficiency more than twofold (39.2% versus 15.5%) in a dose-dependent manner and strongly improved the survival of GFP-positive CD34+ cells. Time course experiments showed that TNF-alpha incubation times as short as 10 minutes were still effective. Neutralizing antibodies to TNF receptor II and RGD peptides diminished the TNF-alpha-dependent increase in transduction efficiency. No TNF-alpha-dependent increase in adenoviral receptors (coxsackie-adenovirus receptor, alphavbeta3-integrin) occurred. Analysis of viral binding demonstrated a significantly higher incidence of local concentrations of Ad along the cell surface (caps) in virus-positive cells of the TNF-alpha-treated group. Plating efficiency, especially the formation of granulocyte-macrophage colony forming units, was enhanced by TNF-alpha pretreatment. We conclude that brief incubation with TNF-alpha before addition of the Ad significantly increased the Ad transduction efficiency in CD34+ cells, and improved post-transduction survival of progenitors of the granulocyte-macrophage lineage. This finding correlates with increased Ad capping at the cell surface and suggests an alteration of Ad trafficking.