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J Krauter

Publications and source records attributed to J Krauter.

22 records · Page 2Linked to original sources
PubMed1998

Fluorescence in situ hybridization and surface markers of fine needle aspiration specimen confirm extramedullary myeloblastoma in a patient with chronic myeloid leukemia.

We report on a patient with chronic myeloid leukemia (CML) with a rapidly growing left cervical tumor 5 months after the initial diagnosis of CML. This tumor was diagnosed as a very early manifestation of extramedullary myeloblastoma by a minimally invasive method. A fine needle aspirate (26-gauge needle) was obtained from the tumor. Morphological and cytochemical analysis of the aspirate revealed 19% undifferentiated blasts. The immunophenotype was suggestive of a myeloid differentiation of the blasts (CD33+). The CML origin of the blasts was confirmed by the detection of the bcr-abl gene rearrangement in the blasts by two-color fluorescence in situ hybridization (FISH). We conclude that fine needle aspiration in combination with immunophenotyping and FISH analysis of the aspirate is a minimally invasive and rapid diagnostic tool to confirm extramedullary manifestation in CML. To our knowledge, this is the first case of extramedullary myeloblastoma confirmed by this combined technique.

Adult↗
PubMed1994

CD 54 expression and its role in homotypic aggregation of the blasts of acute myeloblastic leukemias (AML).

CD 54 (ICAM-1) expression was studied on blasts of 13 cases of de-novo AML prior to and after stimulation by interferon-gamma (IFN-gamma). Furthermore, its functional activity was studied by analysis of the influence of CD 54 on homologous interaction of the blasts. Prior to culture only a minority of the blasts displayed CD 54 positivity. Timed incubation of the blasts in RPMI-1640/FCS or serum-free medium 'spontaneously' increased the percentage of CD 54 positive cells in 11/13 cases with a main increase after 24 h. IFN-gamma (500 IU/ml) further enhanced CD 54 positivity in 6/11 cases. In 2/13 cases neither a 'spontaneous' nor an IFN-gamma induced CD 54 upregulation occurred. The homotypic aggregation of the AML blasts paralleled ICAM-1 expression in that (1) in all but the two CD 54 negative cases autologous cluster formation could be detected, (2) IFN-gamma enhanced cluster formation in 5/6 cases in which it had enhanced CD 54 upregulation, (3) incubation of the blasts in the presence of an anti-CD 54 MoAb (clone 84H10) reduced the 'spontaneous' and IFN-gamma induced cluster formation in a majority of the cases. Taken together, ICAM-1 expression on AML blasts is heterogenous with respect to (1) its 'constitutional' expression and (2) its 'spontaneous' and IFN-gamma-induced upregulation, while it seems to be functionally active once expressed on the surface membrane. The reason for the heterogenity, which did not correlate with the FAB subtype, and its importance remain unclear.

Adult↗
PubMed1993

A new technical approach for the ultrastructural analysis of hematopoietic cells using cell monolayers adherent to electron-transparent melamine resins.

The melamine resin is a polymer of a hexamethylol melamine ether which can coat glass slides with an electron-transparent foil (approximately 80 nm thick) after polymerization by p-toluene sulphonic acid and warming. Provided that the cells had been resuspended in a serum-free medium, normal peripheral blood, or bone marrow cells, blasts of different acute leukemias, cells of B-cell chronic lymphocytic leukemia, and of the cell-lines K562, KG1a, and HL-60 became adherent to the melamine-resin-covered glass slides. The optimal sedimentation time and cell concentration was 45 min and 10(7) cells/ml, respectively. Moreover, in serum-free culture medium the cells could be maintained adherent for up to 96 h without a great loss in cell number and viability. For transmission electron microscopical (TEM) analysis, the monolayers could be embedded in situ in epon after routine fixation and staining procedures. Alternatively, the foils could be removed from the glass and mounted on grids for whole mount electron microscopic analysis (WMEM). Both methods could be combined with immunogold labelling for the detection of surface antigens. This technique permits ultrastructural in situ analysis of morphological and/or immunological changes of cells induced by in vitro stimulation.

Cell Adhesion↗