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H Eichler

Publications and source records attributed to H Eichler.

34 records · Page 2Linked to original sources
PubMed1999

High incidence of maternal HLA A, B and C antibodies associated with a mild course of haemolytic disease of the newborn. Group for the Study of Protective Maternal HLA Antibodies in the Clinical Course of HDN.

Mild courses of haemolytic disease of the foetus or newborn (HDN) due to Rh (D) blood group antibodies are associated with and may therefore be ameliorated by maternal antibodies reacting with human leucocyte antigens (HLA) of the child, an observation drawn from our own earlier data (Neppert J, Kissel K. Lancet 1992;339:1481). This study (i) corroborates this association; (ii) reveals shortcomings in the published data; and (iii) examines the characteristics of HDN cases when these shortcomings have been rectified. Samples from 51 women with antibodies against their child's blood group antigens of the Rh system were analysed for HLA A, B, C and DR antibodies during parturition. The mothers were divided into two groups, either severe or mild, dependent upon the clinical course of the HDN, and the incidence of HLA antibody production was determined for each group. HLA A, B, C and/or DR antibodies were detected in 85.2% of those women whose children had a mild course of HDN prenatally or perinatally (n=27). This is statistically greater than the incidence of 50.0% (Fisher's exact test: p=0.014) found in the group of women whose children had a severe HDN either pre- or perinatally (n=24) and is greater than the 35% (n=20; p=0.0001) found in women without Rh or other irregular antibodies. HLA DR antibodies were detected in three cases. The findings support our hypothesis that maternal anti HLA A, B and C antibodies may protect against a potential severe HDN. We therefore assume that those women will benefit who have already had a child with a severe HDN and in whom HLA antibodies were not previously detected, if HLA antibody production is provoked by subcutaneously inoculating with the father's leucocytes before or at the beginning of the new pregnancy.

Adult↗
PubMed1999

Micro-column affinity test and gel test: comparative study of two techniques for red cell antibody screening.

BACKGROUND AND OBJECTIVES: We describe the results of a comparative evaluation of a gel test (ID Micro Typing) and a micro-column affinity test (MCAT, Cellbind Screen) for red cell antibody screening and identification under routine conditions. MATERIALS AND METHODS: 3,000 serum samples of patients from the Mannheim University Hospital were tested in parallel by means of the gel test and the MCAT, using the low-ionic-strength-saline indirect antiglobulin test and the protein G affinity technique, respectively. Test cells used were the same in all tests. In addition, we performed titration studies with all detected antibodies as well as with 59 frozen sera containing antibodies of known specificity. RESULTS: A total of 154 antibodies (5.1%) were detected, 149 by gel test and 147 by MCAT. The overall sensitivity and specificity of the gel test was 96.8 and 96.5% and of the MCAT 95.5 and 97.2%. No significant differences between the gel test and MCAT were found when the titer scores of all 213 (fresh and frozen) antibodies were used to check the results. The mean scores for the gel test and the MCAT were 26.8 and 28.5, respectively. For anti-Fy(a) and anti-Kell, a significantly higher titration score could be obtained in the MCAT, whereas anti-Lu(a) showed a significantly higher score with the gel test. CONCLUSION: For the screening of unexpected red blood cell antibodies, the MCAT is as sensitive as the gel indirect antiglobulin test. The sensitivity and specificity of the two systems are more or less the same although it seems that IgM antibodies are better detected by the gel test.

Antibodies, Blocking↗
PubMed1998

Photometric evaluation of the solid-phase antiglobulin test using length measurement of the absorption curve.

BACKGROUND AND OBJECTIVES: The very sensitive solid-phase antiglobulin test is used widely in blood group serology. However, a disadvantage of the test is the sedimentation variability of indicator cells during centrifugation, which causes errors in the photometric evaluation. MATERIALS AND METHODS: To solve this problem a technique was developed which depends on the 'length measurement of the absorption curve' of the sedimented indicator cells. RESULTS: 9,075 sera were tested for the presence of alloantibodies on the basis of the visual type of measurement and the newly developed technique. The agreement between the two evaluation systems was 99.94%. No false-negative results were observed. CONCLUSION: The new method allows the complete automation of the solid-phase antiglobulin test, enabling the analysis and evaluation of the solid-phase microtiter plate assay to be more discriminating and safe.

Antibody Specificity↗
PubMed1998

5% Me2SO is sufficient to preserve stem cells derived from cord blood.

On the basis of historical findings, 10% dimethylsulfoxide is still used to cryopreserve stem cells. We studied a final concentration of 5% dimethylsulfoxide in cryopreservation of cord blood-derived stem cells in autologous plasma. In our opinion, a final concentration of 5% dimethylsulfoxide in autologous plasma without further additives is sufficient for cryopreservation of cord blood stem cells in a banking routine.

Blood Banks↗
PubMed1995

Mild course of fetal RhD haemolytic disease due to maternal alloimmunisation to paternal HLA class I and II antigens.

The patient is a pregnant women of African origin with a prior history of spontaneous abortion and newborn dystrophy. The investigation showed an anti-Rh D antibody (IgG isotypes 1 and 3) with an indirect antiglobulin tube test (IAT) titre of 1:512. The monocyte monolayer assay (MMA) proved clearly the interaction of Fc receptors with the maternal anti-D, and so a clinical significance was expected. In spite of this, no signs of severe haemolysis in the Rh-D-positive and direct antiglobulin test-positive fetus could be observed. Furthermore, two HLA class I and II alloantibodies (anti-A10, anti-DR13) directed against paternal and fetal antigens were detected in the serum of the gravida. Both antibodies showed an inhibitory effect on the in vitro phagocytosis capacity of mononuclear cells expressing at least one of the corresponding HLA antigens (immunophagocytosis inhibition (IPI) test). Thus, the mild course of haemolytic disease may be explained by an effective inhibition of the fetal mononuclear phagocyte system by maternal HLA class I and/or class II antibodies resulting in a diminished destruction of anti-D-coated fetal red blood cells.

Adult↗
PubMed1995

The gel test: investigation into the aetiology and the significance of a positive auto-control.

BACKGROUND: Shortly after the gel test was introduced into routine immunohaematology, an increased percentage of patients were reported to show a positive auto-control in the indirect antiglobulin test (IAT) of uncertain significance as the direct antiglobulin test (DAT) in the tube technique was negative. MATERIALS AND METHODS: In our study 13,280 randomized patient blood samples were screened and additional investigations carried out including an analysis of patient histories in the 97 blood samples that were auto-control positive in the gel test. RESULTS: In 87.4%, a re-testing with polyspecific antiglobulin serum (83.2% with anti-IgG) showed positive results in contrast to only 52.9% re-tested by the tube test. Neither nonspecificity nor cold agglutinins were significant. None of the patients examined showed any signs of haemolysis except for one with pernicious anaemia. We concluded that the increased number of positive auto-controls and DATs is due to the greater sensitivity of the gel test and thus the detection of minute quantities of specific cell-bound IgG molecules, i.e. warm auto-antibodies or drug-induced antibodies. CONCLUSION: Prior to transfusion, a positive result should be confirmed by a tube DAT. If this test is negative and there is no history of a previous transfusion or of haemolysis, the transfusion should not be delayed by carrying out further time-consuming investigations.

Adult↗
PubMed1994

[Component removal from whole blood by means of gravity sedimentation].

Our aim was to establish a new method for the separation of long-term storable blood components (red blood cells in additive solution and frozen plasma) from whole blood by a gravity sedimentation technique with hydroxyethyl starch. This investigation should offer a cheap and technically simple method of blood separation as an alternative to whole blood storage, valuable for autologous blood to extend the presurgical donation period. Although the separation of 8 whole blood units was successful, this method cannot be recommended for routine application. It is still too complicated, difficult to standardize and too time-consuming. Additionally, the cell contamination of the plasma is too high.

Blood Donors↗
PubMed1994

[ID and Bio Vue systems--comparison of two systems for the typing of erythrocyte antibodies].

The gel centrifugation test ID Microtyping was compared with the column agglutination test BioVue for antibody (AB) screening by testing serum samples of 3,000 patients under controlled conditions: enzyme test (ET; Bromelin) and LISS indirect antiglobulin test (IAT), both incubated for 15 min at 37 degrees C. From a total of 64 ABs, more relevant or possibly relevant ABs were detected by ID than by the BioVue system (63 vs. 56). ABs only detected in ID were: anti-D 3, -Jk(a), E 1, -Le(b)1, -e 1, -C 1, -E,S 1. One anti-Le(b) was only detected by BioVue. The calculated sensitivity was 98.4% for ID and 87.5% for BioVue. Furthermore, this study showed a lower frequency of unspecific reactions or reactions due to irrelevant cold ABs in the ID system (ID: 2.3%, BioVue: 4.0%, specificity 97.7 vs. 96.2%).

ABO Blood-Group System↗
PubMed1994

[Value of positive auto controls in the gel centrifugation method].

We studied 97 samples of patients being positive in the autocontrol of the indirect antiglobulin test (IAT) in the gel system (DiaMed). In 83.2%, retesting with monospecific anti-IgG serum gave also positive results, due to a specific phenomenon caused, for example, by drug-specific antibodies (AB), warm auto-AB or allo-AB. In contrast, only 52.9% of the samples retested by the standard tube technique with polyspecific antiglobulin serum reacted positive. Only in 6 patients slightly increased cold agglutinins could be detected. None of the investigated patients showed any clinical or laboratory signs of hemolysis except one with pernicious anemia. We conclude that positive results of the autocontrol in the gel IAT should be confirmed by an additional DAT in the tube technique. If this second test shows a negative result, transfusions can take place without any restrictions.

ABO Blood-Group System↗
PubMed1994

[Vacuum ether elution--a modification of the Rubin ether elution method].

The time-consuming ether elution of Rubin can be shortened by vacuum evaporation of the ether (< 10 min). The modification developed by us was compared with the conventional method investigating 103 blood samples with a positive direct antiglobulin test or a possible immunohemolysis. No significantly different results could be obtained with the two different elution methods.

Autoantibodies↗
PubMed1985

[Importance of computed tomography in the diagnosis and differential diagnosis of primary adrenal tumors].

In the present study, 29 patients with primary adrenal tumours and one with an extra-adrenal paraganglioma were examined. With an accuracy of over 90%, computed tomography is the method of choice if there is clinical suspicion of a suprarenal tumour. Pathological changes greater than 8 to 10 mm can be demonstrated. Low absorption values, up to 25 HU, are found predominantly with hyperplasias and adenomas. Phaeochromocytomas, carcinomas and metastases, on the other hand, show significantly higher densities between 30 and 60 HU. CT also demonstrates neighbouring structures. Differentiation between benign and malignant processes is also possible by demonstrating tumour infiltration or metastases.

Adenoma↗
PubMed1983

[Pharmacokinetics and acute signs of cardiac toxicity during doxorubicin therapy].

Doxorubicin (Adriamycin) has shown impressive activity in the treatment of a broad spectrum of malignant tumours. Chronic irreversible cardiac myopathy is the usual cumulative dose-limiting toxicity with this anthracycline antibiotic. In this study acute cardiac reactions following doxorubicin infusions (60 mg/m2) were registered by means of ECG Holter monitoring and measurement of systolic time intervals. The PEPI as well as the PEP/LVET ratio were found to be significantly increased, with a peak at 6 hours following drug infusion (p less than 0.001). This observation proves the occurrence of transient myocardial dysfunction during doxorubicin treatment. Pharmacokinetic data showed good correlation between the electrocardiographic changes and the tissue distribution of the drug. Doxorubicin-related ventricular arrhythmias were observed in only 2 out of 6 cases. Repeated acute myocardial damage by doxorubicin infusions is considered to be the cause of chronic cardiomyopathy with long-term administration.

Adult↗
PubMedDate not supplied

[Aspects of donation and processing of stem cell transplants from umbilical cord blood].

BACKGROUND: In 1996, the Institute of Transfusion Medicine and Immunology started the banking of unrelated cord blood (CB) transplants in collaboration with the Department of Gynecology and Obstetrics at the Mannheim University Hospital. Up to now, more than 2000 placental blood samples have been cryopreserved. We analyze the results of CB collection and processing, and describe the legal background of CB collection in Germany. MATERIALS AND METHODS: CB is only collected with informed consent of the mothers, and without evidence of neither maternal infection nor deformity of the baby. Units with a volume of > 60 ml or > 5 x 10(8) total nucleated cells (NC) are processed as potential transplants. All specimens are evaluated for cell count, HLA typing, sterility testing, ABO/Rh blood groups and clonogenic capacity of hematopoietic progenitor cells. The maternal blood is screened for various infectious disease markers. To reduce the volume of the transplants, we perform buffy coat processing by centrifugation. Finally, we cryopreserve the transplant using a 5.5 percent final concentration of DMSO, and store it in the vapour phase of liquid nitrogen. Results We collected on average 86 +/- 21 ml CB containing 8.87 +/- 3.41 x 10(8) NC (mean +/- SD). 45 percent of the collected units had to be discarded for various reasons. We achieved a mean mononucleated cell recovery by the buffy coat preparation method of 93.4 percent. Defining a threshold dose of 3.0 x 10(7) NC per kg body weight (BW) for transplantation, the mean BW of patients to be sufficiently treated with the stored transplants showed to be 29.6 kg. Conclusions In a very close collaboration between transfusion medicine and obstetricians, a routine collection program for unrelated and related allogeneic CB transplants was established. The CB donation needs to be in accordance with the German drug law. On the other hand, in terms of evidence based medicine, it seems not to be reasonable to collect autologous placental blood for a future transplantation.

Blood Banks↗