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Biomedical subjects

C P Engelfriet

Publications and source records attributed to C P Engelfriet.

At least 91 records · Page 5Linked to original sources
PubMed1983

A comparison of surface marker analysis and FAB classification in acute myeloid leukemia.

Surface marker analysis with rosette tests and a large panel of xenoantisera and monoclonal antibodies was done on the malignant cells of 55 patients with acute myeloid leukemia (AML). The diagnosis was made on morphological and cytochemical grounds, and the leukemias were classified according to the quantified FAB criteria. The marker tests included the E- and EA-rosette test, immunofluorescence with rabbit-polyclonal antisera against human Ig, kappa, and lambda light chains, thymocytes, granulocytes, erythrocytes, platelets, lysozyme, (leukemic) myeloblasts, the common ALL antigen, SB cell-line cells (anti-Ia), and a mouse anti-Ia serum. The monoclonal mouse antibodies applied were anti-T-cell antibody (3A1), two anti-granulocyte-monocyte antibodies (OKM1 and B2.12), four antigranulocyte antibodies (MI/N1, UJ 308, B4.3, and B13.9), an antiplatelet antibody (C17.28), anti-HLA heavy chains (w6/32.HLK), anti-Ia antigen (OKI1), and OKT10. AML cells from many patients lacked the expression of myeloid markers, and we found that a correlation existed between the relative maturity of the leukemia subtype and the extent of positivity for these markers. Surface marker analysis discriminated poorly between the "myeloid" and "monocytoid" subtypes; OKT10 and the "T-cell marker" 3A1 were often expressed on AML cells. In two cases of AML, there was an unexpected expression of platelet antigens with the monoclonal antiplatelet antibody. One of them, classified as M1, was ultrastructurally a megakaryoblastic proliferation with a positive reaction for platelet peroxidase. Only with the help of computerized analysis, was it possible to prove a clear correlation between the surface marker profile and the FAB classification.

Antigens, Surface↗
PubMed1982

Autoimmune haemolytic anaemia with monoclonal IgM (kappa) anti-P cold autohaemolysins.

A patient is described with immunoblastic non-Hodgkin's lymphoma and autoimmune haemolytic anaemia of the cold autoantibody type. The autoantibodies were monoclonal IgM-kappa cold haemagglutinins/haemolysins with blood-group specificity, anti-P. Red-cell autoantibodies directed against blood-group-P antigen have until now only been detected, as polyclonal IgG antibodies, in paroxysmal nocturnal haemoglobinuria.

Agglutinins↗
PubMed1982

The Evans syndrome: characterization of the responsible autoantibodies.

The immunofluorescence test on paraformaldehyde-fixed cells was used for the detection of antibodies bound to the platelets and granulocytes and present in the sera of 24 patients with Evans syndrome and a further 29 patients with both idiopathic thrombocytopenia (ITP) and idiopathic neutropenia (INP), but without autoimmune haemolytic anaemia (AIHA). The direct immunofluorescence test on platelets and/or on granulocytes was positive in all patients with a cytopenia, but the sera of only 17 patients with the Evans syndrome and 15 of the other patients contained platelet- or granulocyte-specific autoantibodies. From absorption and elution experiments, it appeared that the autoantibodies were directed against antigens specific for the various peripheral blood cells, i.e. erythrocytes, platelets and granulocytes and that they were not cross-reacting.

Agranulocytosis↗
PubMed1982

Studies on quinine- and quinidine-dependent antibodies against platelets and their reaction with platelets in the Bernard-Soulier syndrome.

The sera of 14 patients with quinine/quinidine-dependent thrombocytopenia were studied in the platelet suspension immunofluorescence test (PSIFT), the 51Cr-lysis assay and the complement fixation test (CFT). When anti-Ig or anti-IgG reagents were used, the PSIFT proved to be a little more sensitive than the 51Cr-lysis assay and far more sensitive than the CFT. With the PSIFT, it was possible to determine the immunoglobulin class of the antibodies, which in all sera was IgG of the subclass IgG1. In two sera there were also IgG3 antibodies, and in the sera of three patients additional IgM drug-dependent platelet antibodies were detected. With the anti-C3 reagent, however, lower titres were observed in the PSIFT than in the 51Cr-lysis assay, in contrast to the results with other complement-binding IgG platelet antibodies. The F(ab')2 fragments of the antibodies did not react in the PSIFT. This indicates that the Fc part of the antibody is essential for the fixation on the platelet membrane. These findings support the theory that in this syndrome drug-antibody complexes area formed in he absence of platelets that selectively adhere to the Fc receptor on platelets. The platelets of patients with the Bernard-Soulier syndrome (BSS) reacted normally with the quinine/quinidine-dependent antibodies in some of the sera, but not with those in other sera in the PSIFT. However, lysis of BSS platelets was never observed. The results of absorption studies showed a reflection of the results in the PSIFT, indicating that the receptor for the quinine/quinidine-dependent antibodies is not absent in this disease but altered. Whether a reaction with BSS platelets will take place depends on characteristics of the antibodies.

Antibodies↗
PubMed1982

HLA antigens in idiopathic thrombocytopenic purpura.

The lymphocytes of 52 patients with the clinical diagnosis of idiopathic thrombocytopenic purpura (ITP) were typed for the HLA-A, -B and -C antigens, and of 27 of those patients also for the DR antigens. ITP proved not to be significantly associated with any of the HLA-A, -C or -DR antigens tested for. On the platelets of 35 of these 52 patients autoantibodies were detected in the direct immunofluorescence test. In these 35 patients with autoimmune thrombocytopenia (AITP), an increased frequency of HLA-Bw38 was found (14.3% versus 2.6% in controls). The frequency of none of the HLA antigens was significantly increased in the group of 17 ITP patients without demonstrable autoantibodies. The difference in association with HLA-Bw38 between AITP and ITP without demonstrable autoantibodies was not significant.

Adolescent↗
PubMed1982

Elution of granulocyte and platelet antibodies.

By lowering the pH of the medium, allo- and autoantibodies bound to granulocytes and platelets could be eluted from these cells and their presence in the eluate could subsequently be detected with normal donor granulocytes and platelets, respectively, in the immunofluorescence test and/or agglutination test. IgG- as well as IgM- and IgA-containing antibodies were detectable in the eluates. Depending on the attraction mechanism between antigen and antibody, some antibodies were also eluted by dimethylsulphoxide at pH 9.5, ether and/or by heating at 56 degrees C. By differential elution of antibodies from donor platelets, we demonstrated the simultaneous presence of platelet-specific antibodies and HLA antibodies in the serum of a mother whose newborn suffered from transient neonatal thrombocytopenia.

Autoantibodies↗
PubMed1982

Pseudothrombocytopenia: an immunologic study on platelet antibodies dependent on ethylene diamine tetra-acetate.

Antibodies specifically reacting with platelets only in the presence of EDTA, by the platelet immunofluorescence test, were found in the serum of 20 patients with pseudothrombocytopenia due to in vitro EDTA-dependent platelet agglutination. These antibodies reacted optimally at 0-4 degree C. In 19 patients, IgG antibodies were detected; in 8 patients, IgM or IgA antibodies were also found. In one patient, only IgM antibodies were found. In 14 patients, the IgG antibodies were IgG1, but IgG2, IgG3, and IgG4 antibodies were also seen in 7 patients. The reaction of platelets with the antibodies was detectable in the presence of Na2EDTA, the K, Ca, and Mg salts of EDTA, and K2EGTA. F(ab')2 or F(ab') fragments of the IgG antibodies reached as strongly as the intact antibodies, indicating that the reaction is dependent on the antibody-combining site. The EDTA-dependent antibodies did not show platelet-group specificity. However, platelets from patients with Glanzmann disease did not react with the antibodies.

Antibodies↗
PubMed1982

Specificity of autoantibodies in autoimmune thrombocytopenia.

In 42 patients with autoimmune thrombocytopenia (AITP) and a positive direct platelet suspension immunofluorescence test (PSIFT), the antigenic specificity of the autoantibodies was studied. Because the autoantibodies were often not detectable in the serum and additional HLA antibodies may disturb the reaction pattern with the platelet panel, we used eluates prepared from the patients' platelets for this study. Thirty-five patients had antibodies equally reactive with normal platelets, irrespective of their antigenic make-up, but not with the platelets from two Glanzmann's disease patients. Absorption and elution experiments in two patients showed that his was probably not due to the presence of a combination of anti-Zwa and anti-Zwb antibodies. Thus, the majority of autoantibodies against platelets seems to be directed against antigenic determinants not present on Glanzmann's disease platelets, but perhaps located on the platelet-membrane glycoproteins IIb and/or IIIa. In ten patients, antibodies of no, or still unknown, specificity were detected. Three of these had additional antibodies not reactive with the platelets of the two Glanzmann patients.

Antibody Specificity↗
PubMed1982

Immune Unresponsiveness to platelets. A case study.

Both 51Cr-survival studies with donor platelets and allogenic skin transplantations were performed in a patient with immune unresponsiveness to platelet antigens, i.e., HLA-and platelet-specific antigens. The patients, who suffered from hypoplastic anaemia, was successfully transfused with random donor platelets during 13 months. The serum of this patient contained only granulocyte-and mononuclear-cell-reactive antibodies, but no platelet-reactive antibodies. A nearly normal survival time of the donor platelets as well as a prolonged rejection time of a skin allograft of the same donor support the serological findings. The 51Cr-platelet survival time was not influenced by a leucocyte concentrate from the same donor, which was administered at the same time. Thus, in our patient, no increased platelet destruction could be induced via the so-called innocent bystander mechanism.

Anemia, Aplastic↗
PubMed1981

Characterization, by immunoprecipitation, of myeloid- and monocyte-specific antigens present on the human promyelocytic cell line (HL-60) in three stages of differentiation.

The human promyelocytic leukemia cell line HL-60 is reactive with an antiserum raised against normal human granulocytes (AGS). Immunoprecipitation with AGS on [35S]methionine-labeled HL-60 cell lysates with subsequent analysis by NaDodSO4/polyacrylamide slab gel electrophoresis shows a major antigenic doublet with molecular weights of 88,000 and 86,000, together with some minor antigens of lower molecular weight. Upon stimulation with dimethyl sulfoxide or 12-O-tetradecanoylphorbol 13-acetate, which induces HL-60 to differentiate to mature granulocytes or monocytes/macrophages, respectively, this antigenic doublet disappears. 12-O-Tetradecanoylphorbol 13-acetate induces the synthesis of an antigen, molecular weight 83,000, reactive with an antimonocyte serum. Neutrophil-specific alloantigens were not detected on HL-60 or its differentiated derivatives.

Animals↗
PubMed1981

A negative direct antiglobulin test with strong IgG red cell autoantibodies present in the serum of a patient with autoimmune haemolytic anaemia.

The case is presented of a boy with an autoimmune haemolytic anaemia of 10 years duration. He had a positive direct antiglobulin test with IgG and complement detected on the red cells and with IgG autoantibodies in the serum. During a recent episode of severe haemolysis, the Hb level fell to 3.8 g/dl and the direct antiglobulin test became negative although his autoantibodies still reacted with all the red cells in a panel. The serum reacted more strongly with C- and e-positive cells. The Rh phenotype of the patient was CcDee as it had always been. Possible explanations of the unexpected findings are discussed.

Adolescent↗
PubMed1981

Post-transfusion purpura: a serological and immunochemical study.

By applying the platelet suspension immunofluorescence test (PSIFT), platelet-specific alloantibodies responsible for post-transfusion purpura were detected in eight patients within a period of 2 years. All patients were female and had previously received blood or had been pregnant. The platelet-specific alloantibodies had the specificity anti-Zwa in all the patients, who were all Aw(a-). In two patients the platelets were tested in the acute phase of the disease and found to be coated with IgG. In one patient an ether eluate was prepared from the platelets that reacted strongly with Zw(a+) platelets, but weakly with platelets from Zwb-homozygous individuals. The sera of these two patients, and of two others whose platelets were not directly tested, taken in the acute phase of the purpura, reacted strongly with Zwa-positive platelets. The four sera also reacted, however weakly, with Zwa-negative platelets, with autologous platelets taken during remission and with platelets from patients with Glanzmann's disease. It is postulated that Zwa-anti-Zwa complexes, present in the eluate and the sera, caused the reaction with Zwa-negative platelets and the patients' own platelets. Immunochemical characterization of the post-transfusion purpura antibodies showed that in all patients these were IgG, in two combined with IgM antibodies. Antibodies of the sub-class IgG1 were found in all patients, sometimes together with IgG3. In the indirect immunofluorescence test with anti-complement serum, the PTP antibodies in only four sera were able to fix complement. In only two of these sera were these complement-binding antibodies detectable in the 51 Cr-lysis technique and then in a much lower titre than in the immunofluorescence technique.

Aged↗
PubMed1981

Male-female differences in the cytotoxic activity of human monocytes in vitro.

The cytotoxic activity of human monocytes towards anti-D-sensitized Rh(D)-positive red cells in vitro was studied in relation to the age and sex of healthy monocyte donors. It was found that cytotoxic activity of monocytes from young females (age range 18-40 years) was significantly less than that of monocytes from age-matched males, irrespective of the use of oral contraceptives. No such difference was found between monocytes from older males and females (age range 43-63 years). The cytotoxic activity of monocytes from the two latter groups of donors was similar to that of young males. In the presence of cytochalasin B, which enhances the cytotoxic activity of monocytes, no male-female difference was detected, indicating that the maximal cytotoxic capacity of monocytes from young females is similar to that of monocytes from young males. We have previously presented evidence that the cytotoxic activity of monocytes is mediated by lysosomal enzymes released by these cells. These present data suggest that the reduction in cytotoxic activity of monocytes from young females might be a result of a reduced lysosomal enzyme release which is possibly related to the in vivo action of female sex hormones. However, we were not able to detect an inhibitory effect of oestrogens and progestagens on cytotoxic activity of monocytes from males in vitro.

Adolescent↗