Biomedical subjects

A Chott

Publications and source records attributed to A Chott.

At least 19 recordsLinked to original sources

PubMed1998

A case of visceral leishmaniasis in Austria.

We report a patient aged 41 years with fever of unknown origin. Notable aspects of his travel history were a trip to the Philippines and a sailing trip around Sicily. The patient presented with fever up to 40 degrees C since 4 weeks, weakness, headache, hepatosplenomegaly and night sweat. No specific cause could be found. Based on clinical findings tuberculosis was suspected and empirical tuberculostatic treatment was started. However, during the following 6 weeks the patient's condition deteriorated. A bone marrow biopsy performed to exclude a haematological malignancy revealed Leishmania sp. in macrophages. This histological diagnosis was confirmed retrospectively by re-examination of a previously performed liver biopsy and by an increased anti-leishmania serum antibody titer of 1:1280. The patient was treated with sodium stibogluconate (pentostam, 850 mg) for 30 days and recovered slowly.

Adult↗

PubMed1998

Detection of mi transcription factor (MITF) mRNA in a case of myelodysplastic syndrome and bone marrow mastocytosis.

Myelodysplastic syndromes (MDS) may be accompanied by systemic mastocytosis. The mechanisms which play a role in the evolution of mastocytosis, however, are not well understood. We report on a case of refractory and anemia with ringed sideroblasts (RARS), and co-existing bone marrow mastocytosis. Compact mast cell (MC) infiltrates were detected in bone marrow sections by immunohistochemistry using an antibody to tryptase. In addition, the MC were found to express c-kit, the tyrosine kinase receptor for MGF (mast cell growth factor = stem cell factor, SCF). Activating point mutations in the kinase domain of c-kit (often found in mastocytosis) were not detectable. However, the mononuclear cells (MNC) of the bone marrow expressed mRNA specific for MITF, a transcription factor that regulates expression of c-kit and differentiation of MC. Surprisingly, the c-kit ligand SCF was found to augment expression of MITF mRNA in bone marrow MNC. Whether this augmentation represents a general response (preventing loss of growth factor receptor expression during cell maturation) common to all types of hemopoietic progenitors, or is confined to (some forms of) mastocytosis, remains unknown.

Aged↗

PubMed1998

Chromosomal imbalances in primary and metastatic pancreatic carcinoma as detected by interphase cytogenetics: basic findings and clinical aspects.

To date, cytogenetic studies on pancreatic carcinoma are rare, and little is known about the frequency of cytogenetic aberrations in primary carcinomas compared with metastatic tumour cells. We therefore evaluated the frequency of chromosomal aberrations in 12 primary pancreatic carcinomas and in effusion specimens from 25 patients with pancreatic cancer by using interphase fluorescence in situ hybridization (FISH) and a panel of four centromeric probes. Hyperdiploidy and chromosomal imbalances, predominantly affecting chromosome 8, were a constant finding in metastatic effusion cells, whereas concordant gain of chromosomes or relative loss of chromosome 18 characterized primary pancreatic carcinomas. The potential role of oncogenes located on chromosome 8 for pancreatic cancer progression was further investigated by double-hybridization studies of aneuploid effusion cells with a probe to 8q24 (MYC) and a centromeric probe to chromosome 8, which demonstrated amplification of the MYC oncogene in two of ten cases (20%). Finally, a potential application of basic findings in the clinical setting was tested by searching for micrometastatic cells in effusions from pancreatic cancer patients primarily negative by FISH. Two-colour FISH in combination with extensive screening (>10,000 nuclei) seems to be a useful tool to unequivocally identify micrometastatic cells by demonstrating hyperdiploidy and intranuclear chromosomal heterogeneity.

Ascites↗

PubMed1998

Fas ligand expression in nodal non-Hodgkin's lymphoma.

Fas (Apo-1/CD95) ligand (FasL) is a cytotoxic molecule used by T lymphocytes and natural killer cells for target-cell killing and by nonmalignant and malignant cells in the suppression of immune responses. In this study, FasL expression in B- and T-cell non-Hodgkin's lymphomas was investigated by paraffin immunohistochemical analysis. FasL expression was found to be weak in nonaggressive lymphomas (chronic lymphocytic leukemia/small lymphocytic lymphoma, lymphoplasmacytoid lymphoma, Grade 1 follicular center cell lymphoma) and mantle cell lymphoma but strong in aggressive B-cell lymphomas (diffuse large B-cell lymphoma, Burkitt's-lymphoma). Precursor B-lymphoblastic lymphomas were more heterogeneous, with expression varying from weak to strong. In T-cell lymphomas (anaplastic large-cell lymphoma; peripheral T-cell lymphoma, unspecified), strong FasL expression was observed. Apparently, FasL expression is not limited to neoplasms derived from T cells or natural killer cells, and it might play a supporting role in the progression of non-Hodgkin's lymphomas.

B-Lymphocytes↗

PubMed1997

TCR expression in human fetal intestine and identification of an early T cell receptor beta-chain transcript.

TCR expression by human fetal intestinal intraepithelial lymphocytes (ilELs) and intestinal lamina propria lymphocytes was analyzed to address whether T cell development occurs in human fetal intestine, the diversity of human fetal iIELs, and whether human fetal iIELs may contribute to the adult iIEL repertoire. ilELs and intestinal lamina propria lymphocytes from second trimester human fetal intestine were analyzed for TCR-alphabeta transcripts. Rearranged TCR-alpha transcripts were undetectable at 14 wk in the intraepithelial lymphocytes (IELs), whereas multiple TCR-beta transcripts were found at this stage. The TCR-alpha repertoire remained restricted relative to TCR-beta at later stages, and the IEL repertoire was restricted relative to the lamina propria lymphocytes at all stages. A previously reported T early alpha message was the major transcript from the TCR-alpha locus early in gestation. A previously undescribed TCR-beta transcript initiating upstream of the Dbeta1 locus and spliced to Cbeta1 or Cbeta2 was also identified and may represent a T early beta message. These results provide evidence for ongoing TCR gene rearrangement in human fetal intestine and suggest that transcription from the TCR-beta locus initiates with a T early beta transcript. The TCR-alpha repertoire (and hence the repertoire of potentially functional IELs) was limited through the second trimester.

Base Sequence↗

PubMed1997

Analysis of human common bile duct-associated T cells: evidence for oligoclonality, T cell clonal persistence, and epithelial cell recognition.

The phenotype of T cells associated with the common bile duct (CBD) is unknown. We investigated the hypothesis that they behave like other intraepithelial lymphocytes (IEL). Thus, we sought to determine the phenotype, TCR repertoire, and epithelial recognition of T cells obtained during endoscopic retrograde cholangiopancreatography. Three subjects were studied: two with primary sclerosing cholangitis and one normal control. After establishing a short-term T cell line, cells were 1) stained with mAbs for flow cytometric analysis, 2) analyzed for TCRB chain transcript expression, and 3) used as effector cells for cytotoxicity and proliferation. Flow cytometry revealed that for all the subjects 98% of the T cells were TCR-alpha beta-positive. Immunohistology of the CBD showed that the epithelium and lamina propria contained significant numbers of CD3+ CD43+ CD45RO+ lymphocytes. Complementarity-determining region 3 length displays suggested that the CBD-derived lines were oligoclonal. This was confirmed by cloning and random sequencing of PCR amplification products using TCRBV region family-specific primers; TCRB chain sequences were reiterated in all transcripts analyzed. In one case, two expanded TCRB clones could be identified that were persistent in the bile duct over a 1-yr period. The CBD-derived lines were cytolytic in a redirected lysis assay and caused cytolysis of an intestinal epithelial cell line (Caco-2). This recognition was likely preferential for intestinal epithelial cells, since a CBD-derived line exhibited proliferation to two intestinal epithelial cell lines (HT-29 and Caco-2) but not three other lines (HepG2, human foreskin fibroblast, and KD). We conclude that the CBD contains IELs that share several characteristics with intestinal IELs.

Animals↗

PubMed1997

First-line treatment of Waldenström's disease with cladribine. Arbeitsgemeinschaft Medikamentöse Tumortherapie.

PURPOSE: To assess the activity and side effects of cladribine (2-CdA) treatment in patients with advanced Waldenström's disease. PATIENTS AND METHODS: Ten symptomatic patients without prior therapy were included in a prospective multicenter trial. 2-CdA was administered daily at 0.12 mg/kg body weight in a 2-h i.v. infusion over 5 consecutive days: this was repeated every 28 days for four cycles. Patients achieving a remission received interferon alfa-2c (1F) 15 micrograms s.c. three times a week for 1 year. RESULTS: All 10 patients responded to 2-CdA (100%; 95% confidence interval, 68-100%), with one complete (CR) and eight partial responders (PR): one patient had only one 2-CdA cycle and showed a minor improvement (MR). Patients tolerated the treatment well. Despite considerable immunosuppression, an infection occurred in only two patients. After a median observation period of 57 weeks, three patients had shown progression, including one who died of lymphoma. CONCLUSION: 2-CdA induction and IF maintenance is a well-tolerated therapy for symptomatic untreated patients with advanced Waldenström's disease and offers excellent palliation.

Adult↗

PubMed1997

Expression of VS38 in osteoblasts and stroma cells of bone tumors.

VS38 is a mouse monoclonal antibody which recognizes an intracytoplasmic antigen of 64 kilodaltons present in normal and neoplastic cells. It was reported to be of potential value in identifying myeloma or plasmacytoma in bone marrow or other tissues. During diagnostic analysis of bone marrow biopsies we noticed a consistent staining of osteoblasts with VS38. This led us to investigate the immunoreactivity in a range of bone lesions. 58 lesions were examined in the current study, including benign and malignant tumors as well as tumor like lesions and processes with reactive bone formation. The Streptavidin-peroxidase complex technique was applied on paraffin embedded sections, with 3-amino-9-ethylcarbazole serving as chromogen. All osteoblasts of reactive origin and part of the osteoblasts of benign neoplasms showed positive immunostaining. The antibody stained stroma cells in 81.25% (13/16) of the cases of benign osteogenic tumors and in 82.35% (14/17) of the osteosarcomas. Additionally, VS38 labelling was observed in bone tumors of fibrohistiogenic origin such as nonossifying fibroma and giant cell tumor, the histogenesis of which is still being debated. On the whole, it can be concluded that antibody VS38 lacks specificity as a plasma cell marker. It shows, however, a striking affinity to osteoblasts and in part also to stroma cells of osteogenic and fibrohistiogenic bone tumors.

Antibodies, Monoclonal↗

PubMed1997

Intraepithelial lymphocytes in normal human intestine do not express proteins associated with cytolytic function.

Human small intestine contains a very large population of intraepithelial T lymphocytes (IELs) that are oligoclonal, appear functionally to be cytolytic T cells, and may contribute to the normal and pathological turnover of intestinal epithelial cells. This report addresses the cytolytic function of IELs in normal small intestine by examining their expression of molecules that carry out cell-mediated cytolysis. Immunohistochemical analyses of granzyme B, perforin, Fas ligand, and tumor necrosis factor-alpha demonstrated these proteins were not expressed by small intestinal IELs in situ. These proteins also were not expressed by colonic IELs or by lamina propria lymphocytes in the small or large intestine. Granzyme A, however, was expressed by a large fraction of IELs. In contrast to these in situ results, isolated and in vitro activated IELs were shown to express effector proteins consistent with cytolytic T cells, including granzyme B, Fas ligand, tumor necrosis factor-alpha, and interferon-gamma. These results are most consistent with the vast majority of IELs in normal human small intestine being resting cytolytic T cells and suggest that these cells do not contribute to the apoptotic cell death of epithelial cells in normal intestine.

Fas Ligand Protein↗

PubMed1996

Persistent clonal expansions of peripheral blood CD4+ lymphocytes in chronic inflammatory bowel disease.

It is increasingly recognized that chronic Ag exposure may lead to clonal expansions of T cells, including those within the peripheral blood. Inflammatory bowel disease is a chronic, multisystemic disease of unknown origin that predominantly affects the intestine. We sought to determine whether clonal expansions of T cells are present in the peripheral blood of patients with inflammatory bowel disease by an examination of TCR usage. Positively selected CD4+ and CD8+ peripheral blood T cells were isolated from subjects with active ulcerative colitis, Crohn's disease, and diverticulitis and from normal controls. Analysis of complementarity determining region 3 lengths of 24 TCR-beta chain V region families from CD4+ and CD8+ peripheral blood T cells showed a skewed distribution in the three inflammatory groups, consistent with expansion of T cell clones, in comparison to the normally distributed pattern observed among the control donors. Random sequencing of the PCR amplification products of CD4+ peripheral blood T cells from the subjects with ulcerative colitis, Crohn's disease, and diverticulitis revealed reiterative TCR-beta chain sequences that were not found in the normal donors. In subjects with Crohn's disease, the reiterative TCR-beta chain sequences from the CD4+ peripheral blood T cells were persistent over at least a 1-yr period. The persistently expanded TCR-beta chain sequences of CD4+ peripheral blood T cells were identifiable in genomic DNA isolated from archival tissue of intestine from subjects with Crohn's disease and ulcerative colitis by Southern blotting and direct DNA sequencing. An identical twin pair, concordant for Crohn's disease, shared the same reiterative TCR-beta chain sequences in their CD4+ peripheral blood T cells. These studies show that chronic intestinal inflammation is associated with expansions of CD4+ peripheral blood T cells. Furthermore, in inflammatory bowel disease these T cell clonal expansions are persistent and shared among HLA-identical individuals, implicating a response to specific, persistent, and stimulating Ags in these diseases.

Amino Acid Sequence↗

PubMed1996

A common TCR beta-chain expressed by CD8+ intestinal mucosa T cells in ulcerative colitis.

The human intestine contains two populations of anatomically distinct T cells, intraepithelial lymphocytes and lamina propria lymphocytes (LPLs), both of which preferentially use the TCR-alpha beta. Recent studies of TCR alpha- and beta-chain usage by intestinal intraepithelial lymphocytes, which are predominantly CD8+ T cells, have demonstrated that these cells are oligoclonal in normal intestine. This report examined the TCR beta-chains expressed by purified CD4+ and CD8+ T cells from normal colonic lamina propria and from the intestinal mucosa of patients with active ulcerative colitis (UC). The selective expansion of CD8+ T cell clones, and to a lesser extent CD4+ T cell clones, was observed among both normal LPLs and mucosal T cells in UC. These expanded LPL clones from normal donors were all distinct, but the mucosal T cells isolated from five of nine patients with UC contained CD8+ T cells expressing related V beta 3-J beta 1.6 TCRs. These observations provide evidence for an Ag-specific mucosal T cell response in UC. Further studies will be required to identify this Ag and address whether the T cell response to it plays a primary role in initiating the disease or is secondary to the inflammatory response.

Amino Acid Sequence↗

PubMed1996

The dominant T cell clone is present in multiple regressing skin lesions and associated T cell lymphomas of patients with lymphomatoid papulosis.

This study was undertaken to determine the clonality of lymphomatoid papulosis (LyP), its clonal relationship to lymphomas, which occur at high frequency in LyP patients, and to define the cell lineage of Reed-Sternberg-like cells in type A lesions of LyP. Punch biopsies of skin of 11 adult patients with LyP were analyzed for morphologic subtype of LyP, surface antigens, and clonal T-cell receptor (TCR) gene rearrangements. Clonal rearrangements were identified by semiquantitative polymerase chain reaction amplification and sequencing of TCR-beta chain genes in nine patients and TCR-gamma chain genes in two patients. A single dominant clone was detected in multiple separate LyP lesions, often of different histologies, in nine patients. The same clone was detected in LyP lesions and the anaplastic large cell lymphoma (ALCL) of 2 patients and the mycosis fungoides (MF) of 2 other patients. No dominant clone could be detected in one patient with LyP uncomplicated by lymphoma or in a second patient with LyP and MF. A T-cell lineage was evident for RS-like cells in cell culture and in type A lesions. These results show that multiple regressing skin lesions and associated T cell lymphomas (MF and ALCL) are clonally related in most LyP patients, which suggest that the disease in these patients was initiated by a non-random genetic event.

Adult↗

PubMed1995

Structure and function of the CD1 family of MHC-like cell surface proteins.

The CD1 family of proteins are structurally related to MHC class I proteins, but are only distantly related to the class I proteins or other MHC-linked class I-like proteins. Sequence comparisons indicate that the CD1 proteins have evolved into two subfamilies, those which are similar to human CD1a, b, and c and those which are similar to human CD1d. The CD1A-, B-, and C-like genes were deleted from rodents and the CD1D gene was duplicated. CD1a, b, and c are expressed by thymocytes, dendritic cells, activated monocytes, and B cells (CD1c), a tissue distribution which strongly suggests a role in antigen presentation. In contrast, CD1d and its murine homologues are expressed by many cells outside of the lymphoid and myeloid lineages. The CD1 proteins are in most cases expressed as beta 2mg-associated membrane glycoproteins, but may associate with additional proteins. CD1d is expressed on the surface of intestinal epithelial cells in a nonglycosylvated form without beta 2mg. Whether the CD1 proteins function as antigen-presenting molecules is unresolved, but it is unlikely that they present conventional peptide antigens. Strong evidence indicates that murine CD1 proteins are recognized by a population of NK1.1+, CD4+ or CD4-CD8- (double negative, DN) T cells which express an invariant TCR alpha chain. CD1d is most likely recognized by the homologous T cell population in humans. DN alpha beta T cells which recognize CD1a, b, or c have been isolated, including clones which recognize a lipid antigen from mycobacteria presented by CD1b. A third potential population of CD1 reactive cells are CD8+ T cells in the intestinal epithelium. Taken together, these observations indicate that CD1 proteins interact with several specialized populations of T cells. The precise biological functions mediated through these interactions remain to be determined.

Amino Acid Sequence↗

PubMed1995

Increase of bone marrow cellularity during erythropoietin treatment in myeloma.

Treatment of myeloma-associated chronic anemia with recombinant human erythropoietin (rHuEPO) has been shown to be successful in the majority of patients. We have morphometrically investigated bone marrow sections from the iliac crest of 20 anemic myeloma patients prior to rHuEPO therapy. The 15 responding patients were re-examined after three months and, if possible, after 6 and 12 months of treatment. Significant differences were found between responders and nonresponders prior to therapy. Nonresponders presented with a pronounced shift to the right in their erythroid bone marrow cell compartment and partly with higher serum levels of endogenous erythropoietin. During rHuEPO therapy, responders showed increases in all subsets of erythropoiesis and in the total amount of hemopoietic tissue. Response was accompanied by a marked drop of serum ferritin levels, a rise in serum levels of transferrin receptors and the emptying of bone marrow iron stores; the World Health Organization performance status improved. Responders tended to present with less advanced disease stages and better performance status and showed significantly longer survival times. Loss of responsiveness to rHuEPO was observed in one patient during the terminal stage of the disease. In conclusion, morphometric examination of bone marrow biopsies during the course of rHuEPO therapy showed that the response achieved in hemoglobin values was clearly mirrored in equivalent increments of the erythroid bone marrow cell compartment.

Aged↗

PubMed1994

Granulocytic sarcoma of the prostate as the first manifestation of a late relapse of acute myelogenous leukemia.

We describe a 68-year-old patient who developed granulocytic sarcoma of the prostate 9 years after complete remission following successful treatment of acute myelogenous leukemia (FAB, M2). PCR analysis of bone marrow samples in first remission and at the time of relapse detected an AML1/ETO rearrangement typical for AMLs with t (8;21). The CD56 antigen was not expressed on the leukemic cells. Systemic chemotherapy led to a short-lasting regression of the tumor, but the patient subsequently developed overt bone marrow relapse and died during chemotherapy. While granulocytic sarcoma as a primary manifestation of AML is well known, as the first manifestation of relapse it appears to be very uncommon.

Aged↗

PubMed1994

Karyotype and prognosis in non-Hodgkin lymphoma.

In malignant non-Hodgkin lymphomas (NHL), cytogenetic analysis may provide prognostic information including prediction of histologic evolution and responsiveness to therapy. In this study, we correlate clinical data and chromosomal aberrations in 70 adult patients with newly diagnosed NHL followed for a median of 20 months. Clonal aberrations were detected in 68/70 patients (97%). Besides t(2;5)(p23;q35), observed exclusively in three patients with anaplastic large cell lymphoma, Ki-1 positive, none of the characteristic aberrations observed was specific for a given histological subtype. Aberrations of chromosome 7 (n = 21) occurred in all histological subtypes together with aberrations of chromosome 3 and of the short arm of chromosome 17. They were clinically associated with a high serum lactate dehydrogenase level (LDH) and a trend to short survival. Anomalies of the long arm of chromosome 13 (n = 10) were found in patients with high grade B-cell lymphomas and bulky disease. In t(14;18)(q32;q21) bearing lymphomas (n = 27), distinct patterns of additional aberrations were observed in low grade and high grade lymphomas: trisomy 3 and trisomy 18 occurred concomitantly in high grade lymphomas (n = 6, p < 0.001) as well as aberrations of 1q, 5q, 6q and +der (18)(q21). In conclusion, cytogenetic analysis provides information about the complexity of genetic changes in NHL. These changes act not only as indicators of disease activity, but influence clinical outcome as demonstrated by their stringent correlation to the International Index and might reveal more general rules of tumor growth and spreading.

Adolescent↗

PubMed1993

[Manifestation of malignant lymphomatous polyposis of the nasopharynx].

A 66 year old male patient with malignant lymphomatous polyposis of the gastrointestinal tract showed a manifestation in the nasopharynx. After 6 cycles of chemotherapy according to the CHOP-Scheme complete remission could be observed. 9 months after therapy no signs of recurrence were evident.

Aged↗

PubMed1992

[Malignant lymphomatous polyposis of the gastrointestinal tract].

Two years after endoscopic excision of several polyps of the colon (histological examination revealing infiltration by a malignant non-Hodgkin lymphoma) a 67-year-old man was again found to have blood and mucus in his stool. Because local recurrence was suspected a coloscopy was performed. This revealed multiple polyps throughout the entire colon, predominantly in the sigmoid and rectum. Biopsy showed focal infiltration of the submucosa and mucosa with centrocytic non-Hodgkin lymphoma, compatible with the diagnosis of malignant lymphomatous polyposis of the gastrointestinal tract. Gastroduodenoscopy then demonstrated duodenal polyps and massive coarsening of the gastric folds due to infiltration. For the first time tumour masses were also found in the epipharynx. After 6 chemotherapy cycles according to the CHOP scheme (day 1: cyclophosphamide, 1500 mg, adriblastin, 100 mg and vincristine, 2 mg; days 1-5: prednisolone, 100 mg) all lymphoma infiltrates regressed completely. The patient has been symptom-free for 9 months.

Aged↗