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J Schwaller

Publications and source records attributed to J Schwaller.

24 records · Page 2Linked to original sources
PubMed1995

Interleukin-12 expression in human lymphomas and nonneoplastic lymphoid disorders.

Interleukin-12 (IL-12), a cytokine with in vitro and in vivo immunomodulatory effects, is produced by lymphocytes and stimulated monocytes. Little is known about the production and possible role of IL-12 in human lymphoproliferative disorders. We examined IL-12 expression by immunohistochemistry using antibodies recognizing the p40, p35 subunits, and the p70 heterodimeric IL-12 protein, and by Northern blot in lymph nodes from patients with Hodgkin's disease (HD), non-Hodgkin's lymphomas (NHL), and nonneoplastic lymphoid lesions. In the majority of the HD cases (28 of 34), IL-12 immunoreaction was found in small lymphoid cells cultured around Hodgkin and Reed-Sternberg (H&RS) cells. No IL-12 signal was seen in H&RS cells. Transcripts for IL-12 were found by Northern and dot blot analysis in 13 of 19 (IL-12 p40) and 11 of 19 (IL-12 p35) cases. The HD cases were further examined for the presence of Epstein-Barr virus (EBV) latent membrane protein (LMP-1). All cases with EBV-LMP-1 positivity (22 of 34 cases) also expressed IL-12. No IL-12 immunoreaction was found in neoplastic cells of 33 cases of various NHLs, which were all LMP-1 negative and showed no EBV-genome sequence, as assessed by polymerase chain reaction (PCR). In 24 nonneoplastic lymphoid lesions, few dispersed IL-12 positive cells were seen in the parafollicular area and in the sinus of the lymph node. The marked presence of IL-12 in the majority of HD cases indicates that IL-12 might play a role in the pathobiology of HD, suggesting that this cytokine is involved in EBV-positive HD.

Biomarkers↗
PubMed1995

Structural integrity of the cyclin-dependent kinase inhibitor genes, p15, p16 and p18 in myeloid leukaemias.

The cyclin-dependent kinase inhibitors known as p15, p16 and p18 have been suggested as candidates for tumour suppressor genes. We examined these genes for their alterations in 46 myeloid leukaemias and 15 myeloid leukaemia cell lines. p16 mRNA expression was studied in 41 myeloid leukaemias. The p15 and p16 genes were either deleted or mutated in myeloid leukaemia lines at a high frequency [6/15 (40%) for p15; 8/15 (53%) for p16] but alterations in primary myeloid leukaemias are much less frequent [2/46 (4%) for p15; 3/46 (6%) for p16]. Alterations of p18 were not found in any of the samples. 13 primary myeloid leukaemia samples had negligible levels of p16 mRNA. In summary, the deletions of p15 and p16 genes identified in the myeloid leukaemia cell lines probably occurred during their in vitro immortalization. Alterations of the p16 or p15 gene only occurred in primary acute myeloid leukaemia samples that were of mixed myeloid/lymphoid lineage (CD19/CD20-positive acute myeloid leukaemia [AML], CD2/CD19-positive AML, and lymphoid blastic crisis of chronic myeloid leukaemia). Further studies are required to determine if the absence of mRNA expression results from inactivation of the p16 gene.

Blotting, Northern↗
PubMed1995

Posttranscriptional stabilization underlies p53-independent induction of p21WAF1/CIP1/SDI1 in differentiating human leukemic cells.

p21WAF/CIP1/SDI1 is a recently identified gene expressed in cells harboring wild-type but not mutant p53 gene. It encodes a nuclear protein of 21 kD which inhibits cyclin-dependent kinase activity. Constitutive p21WAF1/CIP1/SDI1 mRNA expression was detected in neoplastic cells from patients with various hematological malignancies as well as in normal bone marrow mononuclear cells and in myeloid and lymphoid cell lines independent of their p53 status. Induced differentiation of the p53-deficient promyelocytic HL-60 cells along the monocytic lineage by phorbol ester or 1a,25 dihydroxyvitamin D3 resulted in a marked increase of both p21WAF1/CIP1/SDI1 mRNA and protein expression due to enhanced mRNA stability. Differentiation towards the granulocytic lineage by all-trans retinoic acid or dimethylsulfoxide failed to produce this effect. p21WAF1/CIP1/SDI1 is an immediate early gene since its upregulation occurred independently of de novo protein synthesis. The induction of p21WAF1/CIP1/SDI1 expression and its regulation in p53-deficient differentiating leukemic cells support the idea of an additional, p53-independent role of p21WAF1/CIP1/SDI1 in human hematopoiesis.

Cyclin-Dependent Kinase Inhibitor p21↗
PubMed1995

Cytokine production and visualized effects in the feto-maternal unit. Quantitative and topographic data on cytokines during intrauterine disease.

BACKGROUND: A large array of cytokines show high activity in amniotic fluid. Attempts have been made to quantify the concentrations or to track rising levels for diagnostic purposes when examining disturbances of the feto-maternal unit. However, the kinetics of cytokine production in the amniotic fluid are not well understood, and there is lack of knowledge about concomitant levels in fetal and maternal blood. EXPERIMENTAL DESIGN: The presence of cytokines in fetal and placental cells was demonstrated by immunohistochemistry using mAb. Cytokines were quantified by enzymimmunoassay in amniotic fluid and fetal and maternal blood. This was done with regard to two disease states that quite frequently complicate the course of pregnancy, namely chorioamnionitis and intrauterine growth retardation. The cytokines examined were G-CSF, GM-CSF, TNF-alpha, IL-1, IL-6, and IL-8. RESULTS: In chorioamnionitis, all cytokines, except GM-CSF, were elevated about 100 times in the amniotic fluid. An accompanying increase in maternal and fetal blood was only found for IL-6 and G-CSF; IL-8 was elevated in fetal blood only. Intrauterine growth retardation was characterized by elevated levels of TNF-alpha in the amniotic fluid, whereas G-CSF, GM-CSF, and IL-1 beta were significantly reduced. Immunohistochemistry showed that under normal conditions the cytokines are to be found in a characteristic distribution in certain cell types in the fetus, the placenta, and the placental bed. With rising concentrations, more cells seemed to be recruited for cytokine production, especially macrophages and decidual cells. In chorioamnionitis, fetal extramedullary granulopoiesis was augmented, and in intrauterine growth retardation, erythropoiesis as well as granulopoiesis were depressed. CONCLUSIONS: Not only inflammatory disease but also intrauterine growth retardation is characterized by a changing cytokine pattern. Alterations in fetal hematopoiesis observed at postmortem examination of perinatal deaths can be correlated to changes in cytokine production within the feto-maternal unit.

Amniotic Fluid↗
PubMed1993

Current problems with autologous blood supply.

OBJECTIVE: The purpose of the present study consists in an updated review of recent progress in the field of autologous blood supply. At different medical centers, autologous blood products are collected by quite different procedures, which may be applied during pre-, intra- and/or postoperative periods according the technical possibilities of the local blood supply systems. The products are very different, consisting in whole blood, red cell concentrates, platelet concentrates, fresh-frozen plasma (from whole blood and from plasmapheresis), as well as in wound and drainage fluid and in washed red cell concentrates. Iron therapy against autologous blood donation--or against surgical bleeding-induced anemia--is now well established, but it is unclear whether it should be given perorally or intravenously. In addition, erythropoietin substitution may be necessary for some but not all patients. DATA SOURCES: For our review we have used as sources, beyond our own published reports, studies devoted to clinical experience as well as to pathophysiological aspects of blood donation. RESULTS AND CONCLUSIONS: It becomes apparent that the practice of autologous blood supply has now reached peripheral hospitals not affiliated with bigger medical centers. Smaller hospitals may share expensive equipment necessary for autologous blood collection. Such progress contrasts with persistent uncertainties regarding iron and erythropoietin substitution.

Blood Component Removal↗