A weak blood group A phenotype caused by a new mutation at the ABO locus.

Background: A number of alleles have been described for ABO encoding for common and rare ABO blood group phenotypes. Critical mutations in the coding sequence of ABO that may confer the different specificity and activity of the glycosyltransferases encoded by this gene locus have been identified.

Study Design And Methods: Three unrelated patients from Germany, Turkey, and Bosnia who were diagnosed as having variant A subgroups were subjected to extended ABO typing.

Characterization of the novel allele HLA-B*4417: implications for bone marrow transplantation.

The identification of the novel allele HLA-B*4417, which was found in a blood donor of Caucasian origin, is described. In the sequence analysis the new allele differs from B*4402 by three nucleotides in exon 3. At the protein level, the new allele has two residue differences compared to B*4402.

[Solidscreen II Enzyme: a complete test method using Solidscreen II].

An extended application of the solid-phase antiglobulin test Solidscreen II consists in the use of enzyme-treated test cells. Beside the increased sensitivity in the detection of weak Rh antibodies, 'real enzyme-reactive antibodies' can be detected. A total of 818 serum samples and 404 EDTA plasma samples were tested for red cell antibodies.

[Solid phase techniques in blood group serology].

As alternatives to hemagglutination, solid-phase red blood cell adherence assays are of increasing importance. The adaptation of the new techniques to microplates offers several advantages over hemagglutination. Using microplates the assays may be processed semiautomatically, and the results can be read spectrophotometrically and interpreted by a personal computer.

Human monoclonal antibodies for the differentiation of Rh-D categories.

With the introduction of human monoclonal antibodies against antigens of the Rh-system it was possible to solve a series of problems, as, for instance, the permanent availability of reagents. Another problem, the classification of D-categories with a panel of specific monoclonal antibodies, also might be solved by the production of such antibodies. Especially the classification of Cat.

Human monoclonal antibodies for the differentiation of RhD categories.

With the introduction of human monoclonal antibodies against antigens of the Rh system it was possible to solve a series of problems as, for instance, the permanent availability of reagents. Another problem, the classification of D categories with a panel of specific monoclonal antibodies, also might be solved by the production of such antibodies. Especially the classification of cat.

Human leucocyte antigens in idiopathic nephrotic syndrome in children.

An association of the idiopathic nephrotic syndrome (NS) with certain human leucocyte antigens (HLA) has been reported repeatedly. The aim of this study is to characterize further the clinical and histological features of patients with NS in relation to their HLA phenotypes. HLA antigens were determined in 132 paediatric patients with NS.

[Effect of immunomodulation following allogeneic blood transfusion on tumor neogenesis and growth--experimental studies in rats].

The influence of allogeneic blood transfusions (BT) on experimental tumor growth was investigated in three syngeneic, one allogeneic and one autochthonous tumor model in the rat. Con A induced T-cell response, relative distribution of lymphocyte subsets using flow cytometry and cytotoxic antibodies were determined. No differences in take rate, induction time, incidence and growth rate of tumors were observed in the different models.

Suppression of antibody response and prolongation of skin graft survival by multiple blood transfusions in the rat.

The effect of blood transfusions (BT) on antibody response and skin graft survival was studied in the strongly MHC-incompatible BN and LEW combination. One-to-three BT induced high titer antibodies. Additional BT, however, led to a decrease of antibody titers.

Effect of allogeneic blood transfusions on the growth of two different tumours in the rat.

The effect of allogeneic blood transfusions on tumour growth was studied in the rat. BD IX animals pretreated by five blood transfusions from SD rats were transplanted with two different syngeneic malignant neurogenic tumours (neurinoma, ependymoma). The tumour growth rates in the transfused animals were compared to those of non-transfused controls.

Transfusion-induced enhancement of prostaglandin and thromboxane release in prospective kidney graft recipients.

Pre-transplant blood transfusions (BT) improve the survival of kidney grafts. Apart from specific immunoregulation by T suppressor cells or anti-idiotypic antibodies, the role of non-specific immunoregulatory factors, such as prostaglandins is being discussed as a possible mechanism for this effect. We studied the in vitro prostanoid release from peripheral mononuclear cells following three deliberate blood transfusions.

A rapid screening technique for lymphocytotoxic antibodies using tray-frozen lymphocytes.

A method whereby sera can be screened for the presence of lymphocytotoxic antibodies within 4 hr using lymphocytes frozen in microtest trays is described. The reactions of the sera of 48 hemodialysis patients against freshly prepared lymphocytes were compared with those against tube-frozen (384 reaction pairs) and tray-frozen (864 reaction pairs) cells. There was a better than 90% concordance, and only 3% of the reactions differed from negative to strongly positive or vice versa.

[Mesangial IgA-glomerulonephritis].

IgA-glomerulonephritis represents the most frequent glomerulonephritis (GN; 20%) among our patients. In contrast to data from the literature the prognosis is not benign. Renal insufficiency developed in 17 out of 50 investigated patients within 4 to 96 months, 3 of these patients had to undergo dialysis.

HLA-DR-MT matching improves graft survival rate in cadaver kidney transplantation. A prospective multicenter analysis of the South German Cooperative Study Group for Kidney Transplantation.

The influence of prospective HLA-DR matching on the graft survival rate was investigated in a multicenter analysis of 85 transplants. Simultaneously in a retrospective analysis of graft outcome the importance of matching for MT-antigens MT1, MT2 and MT3 as a newly defined B-cell alloantigen system was evaluated. HLA-DR antigens and MT-specificities were determined on B-cells enriched by nylon-wool filtration using locally well characterised HLA-DR antisera and the antiserum set of the 8th International Histocompatibility Workshop ("disease set") which allowed the definition of the HLA-DR specificities HLA-DR 1-9 and of the MT-antigens MT1-3.

HLA phenotypes and idiopathic nephrotic syndrome in children.

Ninety-four children with idiopathic nephrotic syndrome (17 steroid-resistant with a histological diagnosis of a focal segmental glomerulosclerosis) were typed for HLA-A, B and DR antigens. The patients showed a significant increase of DR7 (58% vs 18%, p less than 0.0001) and of B8-DR3 (27% vs 5%, p less than 0.

Clinical and serological features of mesangial IgA glomerulonephritis.

IgA-glomerulonephritis (IgA-GN) accounts for approximately 20 per cent of all glomerulonephritis in our unit. Seventeen out of 50 patients with IgA-GN developed renal failure, which appeared in 11 out of 17 over the course of a mean follow-up of 68 months. Haemodialysis was required in three patients.

Influence of Lewis and other blood group systems in kidney transplantation.

In 167 first cadaver kidney recipients and their donors the blood groups ABO, Rhesus, Lewis, MN, Ss, P, Kell and Duffy were determined. The influence of incompatibility in each system as well as of simultaneous presence of several mismatches was analysed. Whereas one-year graft survival of Lewis-compatible grafts was 67 per cent (p = 0.

Immunological factors influencing renal graft survival.

The results of clinical renal transplantation are determined mainly by immunological factors, the most important of which are compatibility for the HLA chromosomes and pretransplant blood transfusions. Other factors include HLA matching in cadaver transplantation, compatibility for the Lewis blood group system, and sensitization to lymphocyte panels or to endothelial-monocyte antigens. Performance of the previous graft is the most reliable predictor of success in recipients of retransplants.

[Occurrence of HLA-antigens in patients with hypertrophic cardiomyopathy].

The etiology of hypertrophic cardiomyopathy with (HOCM) and without obstruction (HCM) is poorly understood. Controversial data have been published concerning the association of HLA-B-12-antigen with HOCM and HCM respectively. Further, HLA-D-antigen occurrence has been determined in few patients with HOCM or HCM.

[Current immunologic aspects of kidney transplantation].

The results of clinical kidney transplantation are mainly dependent on immunologic factors many of which are unknown or of unspecified importance. Blood transfusions have a favorable effect on graft prognosis, although our knowledge about optimal transfusion protocols and transfusion-induced mechanisms is still incomplete. The value of HLA-typing is controversial: whereas compatibility of the "classical" HLA-A,B,C antigens improves graft survival only moderately, HLA-DR typing, routinely performed for the last 3 years only, might be of greater importance.