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S E Jansson

Publications and source records attributed to S E Jansson.

At least 37 records · Page 2Linked to original sources
PubMed1994

Flow cytometric analysis of glutathione-S-transferase-pi in acute leukemia.

Increased expression of glutathione-S-transferase isoenzyme pi (GST-pi) may account for drug resistance and treatment failure in hematologic malignancies when alkylating agents like cyclophosphamide, chlorambucil, busulfan and melphalan, or doxorubicin are used. We have studied the expression of GST-pi in peripheral blood lymphocytes of healthy blood donors. In peripheral and bone marrow lymphocytes/blasts of patients with other diseases than hematologic malignancies, and of patients with acute leukemia by using flow cytometry. We studied bone marrow cells of 35 patients diagnosed as having acute leukemia at initial presentation, 16 patients in the refractory stage, 20 in morphological remission and 15 controls. None of the samples obtained in remission contained more GST-pi-positive cells than the controls, whereas 51% of the samples obtained at diagnosis and 56% of those obtained in the refractory stage were GST-pi-positive. The mean proportion of GST-pi-positive cells in the lymphocyte/blast cell gate of bone marrow cells of controls was 2.6% and of patients with acute leukemia studied at diagnosis 16.6%, respectively. We analyzed the samples also for P-glycoprotein expression. There was a significant positive association between GST-pi and P-glycoprotein expression in acute leukemia.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed1994

Flow cytometric detection of residual disease in acute leukemia by assaying blasts co-expressing myeloid and lymphatic antigens.

A method employing CD45-gating of blast cells was evaluated for the flow cytometric detection of residual disease in CD19- and myeloid antigen-positive acute leukemia in morphologic remission. In the normal bone marrow, CD45-gating identified at least three populations of immature cells, one of which appeared to retain a minute fraction of CD19- and CD13/33-antigen co-expressing cells. In acute leukemia, CD45 expression separated the blast cell population from the normal marrow cell populations. In the majority of patients with CD19- and myeloid antigen-positive acute leukemia, subpopulations of blast cells with this mixed phenotype were detected during morphologic remission.

Antigens, CD↗
PubMed1993

Flow cytometric determination of CD11b upregulation in vivo.

We describe a flow cytometric method to evaluate upregulation of peripheral blood neutrophil and monocyte integrin CD11b in vivo. To avoid spontaneous upregulation in vitro, buffy coat cells were separated on ice and all subsequent cell handling steps were carried out at 0-4 degrees C. Such leukocytes were 95-100% viable, as determined by PI staining. Buffy coat leukocytes were double-stained with CD11b PE-conjugated and CD14 FITC-conjugated monoclonal antibodies and, in addition, with the nucleic acid dye LDS-751. After staining, firstly, LDS-751 positive (+ve) leukocytes, and, secondly, CD14 +ve monocytes were collected in live mode. Aggregated and irrelevant cells were gated out on the basis of their LDS-751 staining pattern and cellular light scattering properties, and the CD11b expression on neutrophils and monocytes was determined. Upregulation of CD11b in vitro was significantly affected by factors such as cell handling temperature, pre-fixation of blood samples, and density gradient separation of the cells. Incubation of aliquots of buffy coat cell suspension supplemented with FMLP for 5 min or without FMLP supplement for 15 min at 37 degrees C significantly increased CD11b expression without affecting cell viability. We have demonstrated that CD11b is expressed at maximal levels on arthritic synovial fluid neutrophils and CD14 +ve cells, and at increased but submaximal levels on peripheral blood neutrophils and monocytes of patients recovering from sepsis. The results suggest that the method can be used to evaluate in vivo upregulation of CD11b.

Adult↗
PubMed1993

Flow cytometric analysis of terminal deoxynucleotidyl transferase. A simplified method.

The authors evaluated a new cell membrane permeabilization method for the flow cytometric detection of terminal deoxynucleotidyl transferase (TdT). In this method, gradient-separated leukocytes or unseparated blood or bone marrow cells were incubated in a commercially available diethylene glycol-based red blood cell lysing solution, which not only lyses red blood cells, but also permeabilizes leukocyte cell membranes; the light scattering properties of the cells are retained. The validity of the current method was demonstrated by the good concordance of the findings with previously published data as follows: (1) practically identical results were obtained when an established method for cell permeabilization was used in parallel on the same samples; (2) the proportion of TdT-positive cells in normal peripheral blood was negligible; (3) the proportion of TdT-positive cells in normal bone marrow averaged 1%, and a significant portion of TdT-positive cells in normal bone marrow expressed CD10 and CD34; and (4) TdT-positive cell populations were seen with the expected frequencies in various types of leukemia. This method for TdT flow cytometry provides significant advantages over previously used methods and is especially suitable for TdT detection in routine laboratories.

Antigens↗
PubMed1993

Clinical significance of P-glycoprotein expression in acute leukaemia as analysed by immunocytochemistry.

Multidrug resistance, mediated by the overexpression of an energy-dependent transport protein, P-glycoprotein, has been one of the major targets of interest in solving the mechanisms of clinical drug resistance of malignant cells. To evaluate the correlation between P-glycoprotein overexpression and the response to chemotherapy, we analysed cytospin preparations of gradient-separated blood or bone marrow mononuclear cells from 79 patients with acute leukaemia by means of the P-glycoprotein-directed monoclonal antibody JSB-1 and immunocytochemistry using the alkaline phosphatase-antialkaline phosphatase technique. P-glycoprotein expression was detected in all disease phases of acute leukaemia. Thirteen out of 51 patients at diagnosis, 10/29 patients in relapse or during residual disease and 8/27 patients in remission overexpressed P-glycoprotein. Seven out of the 8 positive remission samples were collected between the cycles of consolidation treatment. Our results suggest that increased P-glycoprotein expression in samples collected between the cycles of consolidation treatment during remission may be induced in normal leukocytes by cytotoxic drug treatment, infections, or by some physiological mechanisms related to the disease. Patients older than 45 years of age were significantly more often P-glycoprotein-positive (11/25) at diagnosis than younger patients (2/26). P-glycoprotein expression at diagnosis was significantly correlated with a low remission rate after the first cycle of induction therapy. Of 34 P-glycoprotein-negative patients, 25 achieved remission after the first cycle as compared to 4/12 of the P-glycoprotein-positive patients. Our results indicate that the method used is specific and sensitive enough for the analysis of P-glycoprotein expression and that the expression at initial presentation is inversely correlated with the outcome of induction therapy.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed1993

Monitoring of adult B-cell lineage acute lymphoblastic leukemia: validation of a simple method for detecting immunoglobulin heavy chain gene clonality.

Most approaches to demonstrating immunoglobulin heavy chain gene rearrangements are relatively laborious for routine follow-up of acute lymphoblastic leukemia (ALL). Here the use of a simple polymerase chain reaction (PCR) approach to monitor ALL disease activity has been validated. In the dilution experiments the method revealed a detection sensitivity 0.5% clonal cells in a background of 99.5% normal cells. To validate the immunoglobulin heavy chain gene PCH (IgH-PCR) in practice, we monitored the disease activity of 26 adult ALL patients showing a B-cell lineage component in immunophenotyping at the diagnosis of the disease. In 18 of those 26 patients, an IgH-PCR product could be demonstrated in the samples taken either at diagnosis or in relapse. These 18 patients were followed with a total of 158 consecutive samples by IgH-PCR. The mean follow-up time for the IgH-PCR-positive patients was 13.6 months (range 4 to 26 months). Eleven of these patients underwent altogether 18 relapses. In nine patients (81.8%), ten relapses (55.6%) could be predicted using the IgH-PCR approach. The mean time of IgH-PCR clonality detection, preceding a cytologic relapse, was 9.1 weeks (range 1.0 to 30.7 weeks). It seems that in three patients the predictive value of the IgH-PCR was remarkable, showing a repetitive positivity in spite of a cytologic remission, even one year prior to the relapse. We find that IgH-PCR provides a straightforward additional tool for monitoring B-cell lineage ALL. Due to the straightforward technical performance the method has low running costs and it is thus suitable for a routine service laboratory. Even if a negative finding in IgH-PCR does not rule out a forthcoming relapse in the patient, a positive finding is a definitive warning signal. All of the patients that showed an IgH-PCR clonality in the follow-up samples relapsed sooner or later.

Adolescent↗
PubMed1993

Hypermethylation of the calcitonin gene in the myelodysplastic syndromes.

It is well documented that the calcitonin gene area in the short arm of chromosome 11 is hypermethylated in most acute leukemias as well as in chronic lymphatic leukemia. In contrast, the gene is normally methylated during the chronic phase of the chronic myeloid leukemia but turns hypermethylated as the disease escalates. As the methylation of the calcitonin gene correlates with the disease activity in chronic myeloid leukemia, it seemed worthwhile to study the gene methylation in other premalignant hematologic conditions with a potential to terminate in fulminant acute leukemia. We report here on the calcitonin gene methylation in patients with myelodysplastic syndromes (MDS) using a methylation sensitive restriction enzyme HpaII and standard Southern blotting techniques. Bone marrow aspirates from a total of 26 MDS patients were studied. In 24 of these patients, the calcitonin gene was hypermethylated. There was no correlation between the methylation status and the morphological stage of the disease. All six patients with a blast count < 5% had a hypermethylated gene. Of the 19 patients with a blast count > 5%, 17 were hypermethylated only two having normal methylation status of the gene. It appears that the hypermethylation of the calcitonin gene area in the short arm of chromosome 11 may be an early event in the pathogenesis of the myelodysplastic syndromes. The methylation analysis may thus be of value as a diagnostic tool in MDS but an abnormal methylation pattern does not seem to have a direct relation with the degree of blast infiltration.

Acute Disease↗
PubMed1992

Flow cytometric analysis of P-glycoprotein in normal and leukemic cells.

Classical multidrug resistance is characterized by overexpression of a membrane protein, P-glycoprotein, which acts like a drug-extruding pump, reducing accumulation of cytotoxic drugs inside malignant cells. We have developed a simple method for detecting an intracellular epitope of P-glycoprotein in normal and leukemic cells by the monoclonal antibody JSB-1 and fluorescence-activated flow cytometry. Permeabilization of blood and bone marrow cells in unprocessed samples is achieved by a commercially available red blood cell lysing solution which excellently preserves the light scatter properties of leukocytes. The method is suitable for analyzing samples in clinical routine. Lower than 1% reactivity was seen in the lymphoid gate of normal peripheral blood and bone marrow samples as compared with over 60% of reacting cells in some leukemic samples. Twelve patients with acute de novo leukemia were studied at presentation, 13 patients at a refractory stage, and 28 in remission. There was a positive correlation between the P-glycoprotein and the CD34 expression in acute myelogenous leukemia and an association between the P-glycoprotein expression and the blast count in both acute myelogenous and lymphatic leukemias.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed1991

Acceleration of chronic myeloid leukemia correlates with calcitonin gene hypermethylation.

Calcitonin gene methylation at CCGG sites were determined in 39 chronic myeloid leukemia patients by isoschizomeric restriction endonuclease analysis. A total of 27 patients were analyzed while still in the chronic phase: 20 patients had a normal gene, and seven had a hypermethylated gene. There were 12 patients initially studied in accelerated or blastic phases. All but one patient showed gene hypermethylation, suggesting a good correlation between gene methylation and disease stage. All five patients who, while still in the chronic phase, had a major 3.1-kb hypermethylated calcitonin gene fragment, accelerated within 2 to 27 months. In consecutively analyzed patients, the initially normal calcitonin gene changed to a hypermethylated state as the disease escalated. The hypermethylation predicted disease acceleration with a median lead time of 6 months before any morphologic or clinical signs of disease progression were seen. The disease progressed in 8 of 27 patients initially studied in the chronic phase: in only two patients this occurred without predictive methylation changes. The results suggest that the assessment of calcitonin gene methylation status may be a promising tool for monitoring chronic myeloid leukemia disease escalation.

Biomarkers, Tumor↗
PubMed1985

Cytochemical demonstration of estrogen binding sites in breast cancer by estradiol covalently linked to horseradish peroxidase.

17 beta-Estradiol-6-carboxymethyloxime was covalently linked to horseradish peroxidase for the cytochemical demonstration of estrogen binding sites in breast cancer tissue. The affinity of the 17 beta-estradiol-horseradish peroxidase (E2-HRP) conjugate for the estrogen receptor in a human myometrial cytosol preparation was reduced by a factor of about 16 relative to that of 17 beta-estradiol. The estradiol concentration of the E2-HRP conjugate used in the incubations was in the range 2 X 10(-9) -1 X 10(-7) mol/l which, when the reduced affinity of the conjugate is taken into account, corresponds to 1 X 10(-10) -7 X 10(-9) mol/l unbound estradiol. The cytochemical reaction was carried out on cytofuge preparations of cell suspensions of breast cancer tissue. The intensity of the cytochemical reaction was microscopically evaluated by scoring. The results were analyzed in a plot allowing the calculation of an apparent score-max and an apparent Kd value. The reaction intensity was reduced to 20-25% of the control level by a 20-fold excess of 17 beta-estradiol. The cytochemical results correlated positively with the content of estrogen receptors in the cytosol as measured by a validated radioligand method.

Breast Neoplasms↗
PubMed1985

The Mr 95,000 gelatin-binding protein in differentiated human macrophages and granulocytes.

Cultured adherent human macrophages and a promonocytic cell line, U 937, were previously shown to produce a Mr 95,000 gelatin-binding protein. The protein has no immunologic cross-reactivity with the well-characterized gelatin-binding protein fibronectin and the Mr 70,000 gelatin-binding protein produced by a variety of mesenchymal or epithelial cell types (T. Vartio et al, J Biol Chem 257:8862, 1982). In the present study the Mr 95,000 protein was found in Triton X-100 extracts of granulocytes purified from human blood buffy coat. The protein, as isolated by gelatin-agarose, was immunologically cross-reactive with the corresponding macrophage protein in immunoblotting assay. When peripheral blood and bone marrow cells were examined for the presence of the Mr 95,000 protein by indirect immunofluorescence, positive staining was detected only in differentiated granulocytes but not to any significant extent in metamyelocytes, myelocytes, promyelocytes, or in normal or leukemic blasts. In granulocytes the protein had a granular cytoplasmic distribution. In freshly prepared monocyte cultures, the Mr 95,000 protein was detected in low amounts in the cytoplasm, while along with differentiation of the cells into macrophages, the immunofluorescence increased in a reticular and vesicular cytoplasmic pattern and in a juxtanuclear cap, probably representing the Golgi complex. In conclusion, the Mr 95,000 gelatin-binding protein was specifically detected in macrophages and granulocytes and may thus serve as a differentiation marker for these phagocytic cells.

Adult↗
PubMed1983

Value of liver and spleen aspiration biopsy in malignant diseases when these organs show no signs of involvement in sonography.

To determine whether an aspiration biopsy of liver and/or spleen is likely to reveal a clinically silent malignant infiltration, fine-needle aspiration biopsies were carried out in 180 patients with a diagnosed malignancy in whom neither the liver nor the spleen gave signs of involvement in sonography. Few, if any, findings were positive in patients with cancer or Hodgkin's disease. In non-Hodgkin lymphoma, about 25% of the biopsies were positive for malignancy or aroused suspicion of malignancy. We conclude that fine-needle aspiration biopsies of the liver and spleen may be of value in the clinical follow-up of non-Hodgkin lymphoma.

Adolescent↗
PubMed1983

A spin label study on the effect of dibutyryl cyclic AMP on synaptic plasma membranes isolated from rat brain.

The fluidity of the deep layer of the lipid bilayer and the mobility of sulphydryl (-SH) groups of synaptic plasma membranes, isolated from rat brain and spin-labelled with a doxyl derivative of stearic acid and with a nitroxide derivative of maleimide, respectively, were studied using electron spin resonance (ESR) techniques. Dibutyryl cyclic AMP (db-cAMP) and adenosine triphosphate (ATP) had no effect on the fluidity of the deep layer of the lipid bilayer of synaptic plasma membranes. While protein dephosphorylation was inhibited by Zn2+, db-cAMP together with ATP increased the mobility of -SH groups above the value obtained with db-cAMP alone.

Adenosine Triphosphate↗
PubMed1982

Independent release of supranormal acetylcholine quanta at the rat neuromuscular junction.

This electrophysiological study deals with the occurrence and with the mode of release of unusually large miniature end-plate potentials at the rat neuromuscular junction during physiological conditions. A specific limit for the normal miniature end-plate potential amplitude at each cell studied was determined after fitting the observed frequency-amplitude histogram to a Gaussian distribution. The relative abundance of giant miniature end-plate potentials was 4.15% at room temperature. The occurrence of giant miniature end-plate potentials was temperature dependent. The percentage of giant miniature end-plate potentials was 5.8% and 0.61% at 35 degrees C and at 16 degrees C, respectively. The amplitude-independence of the intervals between miniature end-plate potentials was demonstrated at room temperature as well as at 35 degrees C and at 16 degrees C. The results of this study show that giant miniature end-plate potentials are produced by acetylcholine packets which are released independently and that they are not a consequence of the synchronous release of several normal-sized quanta. Moreover, the results indicate that during physiological conditions a minor but regular proportion of the spontaneous release of acetylcholine is made up of larger packets, which produce miniature end-plate potentials of supranormal amplitude.

Acetylcholine↗
PubMed1982

Effect of prostaglandin E1, dopamine and dibutyryl cyclic AMP on the fluidity of synaptosome membranes.

The membrane fluidity of synaptosomes, isolated from rat brain and spin-labelled with doxyl derivatives of stearic acid, was studied using electron spin resonance techniques. Prostaglandin E1 fluidized while dopamine ordered both the surface and intermediate lipid layers of the synaptosome membranes. At corresponding concentrations these substances have been shown to modulate synaptic transmission. A possible thermal phase transition of the membrane lipid bilayer was observed at about 35 degrees C (the abrupt change in the Arrhenius plot). Dopamine abolished this thermal change. Dibutyryl cyclic AMP had no significant membrane effects.

Alprostadil↗