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Biomedical subjects

A Janin

Publications and source records attributed to A Janin.

At least 145 records · Page 8Linked to original sources
PubMed1994

Synovial fibroblast-like cell transfection with the SV40 large T antigen induces a transformed phenotype and permits transient tumor formation in immunodeficient mice.

OBJECTIVE: To understand the intracellular signals leading to transformed-like growth of synovial fibroblast-like cells from patients with rheumatoid arthritis (RA). METHODS: Cell lines stably transfected with one or both of 2 complementary oncogenes, the SV40 large T antigen and the ras oncogene, were studied for phenotypic changes. RESULTS: Synovial fibroblast-like cells stably transfected with the SV40 large T antigen, but not the ras oncogene, showed high levels of growth factor independent proliferation, grew under anchorage independent conditions, expressed cathepsin L mRNA, and formed transient tumors in immunodeficient mice. Synovial fibroblast-like cells stably transfected with both oncogenes appeared phenotypically similar to synovial fibroblast-like cells transfected with the large T antigen alone. CONCLUSION: The SV40 large T antigen confers a phenotype on synovial fibroblast-like cells similar to that stimulated by growth factors, suggesting that it stimulates the same intracellular signalling pathway leading to cytokine induced, transformed synovial fibroblast-like cell growth. When injected into immunodeficient mice these transfected cells formed tumors characterized by rapid, transient growth, central necrosis, and neutrophil infiltration.

Animals↗
PubMed1993

Synthesis of interleukin-5 by activated eosinophils in patients with eosinophilic heart diseases.

Eosinophilic endomyocardial disease represents a major evolutive risk in chronic eosinophilia-associated disorders. Eosinophil granule proteins appear to be involved in cardiac injury, but the mechanisms leading to eosinophil infiltration and degranulation are not clear. Interleukin-5 (IL-5) has been recently shown to be produced by eosinophils and might play a role in both chemoattraction and degranulation of eosinophils. In four cases of eosinophilic diseases with severe cardiac failure, we evaluated the proportion of eosinophil phenotypes and the serum levels of eosinophil cationic protein (ECP) and soluble IL-2 receptor (sIL-2R), markers of disease activity in the hypereosinophilic syndromes. All four patients showed a markedly increased proportion of hypodense eosinophils with elevated serum ECP and sIL-2R levels. In all four patients, extracellular deposition of eosinophil granule proteins and features of eosinophil activation were observed in cardiac tissues. The synthesis of IL-5 by eosinophils was detected in myocardial sections and blood cells by in situ hybridization and by immunostaining with a monoclonal antibody against human IL-5. Sixty percent to 90% of tissue eosinophils expressed IL-5 mRNA and IL-5 protein. These data suggest that IL-5 can be produced by eosinophils at the sites of myocardial tissue damage and might participate in local eosinophil activation.

Biopsy↗
PubMed1993

Conjunctival biopsy in scleroderma and primary Sjögren's syndrome.

Keratoconjunctivitis sicca complicates both scleroderma and Sjögren's syndrome. Scleroderma of recent onset is difficult to diagnose, but is easily recognized late in its course. To assess the value of the conjunctival biopsy in the diagnosis of scleroderma, we used light, scanning, and transmission electron microscopy to compare in a masked fashion specimens from 21 patients with scleroderma and 14 patients with primary Sjögren's syndrome. Epithelial changes permitted diagnosis of early scleroderma in the two groups of patients. Lymphocytic infiltrate was always present in Sjögren's syndrome, but not in scleroderma. Fibrosis was always found in scleroderma, even in scleroderma of recent onset, but was absent in Sjögren's syndrome. The fibrosis was distributed around capillaries in a band-like pattern and was associated with degranulating mast cells. Conjunctival biopsy is valuable for the early diagnosis of scleroderma and for differentiating between scleroderma and primary Sjögren's syndrome.

Adult↗
PubMed1993

Labial salivary gland biopsy is a reliable test for the diagnosis of primary and secondary amyloidosis. A prospective clinical and immunohistologic study in 59 patients.

OBJECTIVE: Reports of the detection of amyloidosis by labial salivary gland (LSG) biopsy have been mostly anecdotal. The aim of this study was to assess the value of this method in the diagnosis of amyloidosis. METHODS: LSG biopsy tissues were studied with a combination method using Congo red stain and immunohistologic characterization using an antibody directed against the serum amyloid P (SAP) component. Electron microscopy was performed in all cases. In a prospective study, we evaluated 30 patients with biopsy-proven AA or AL amyloidosis. We compared these patients with a control group of 29 age-matched patients without clinical or biologic evidence of amyloid disease (14 had rheumatoid arthritis and 15 had plasma cell dyscrasia). RESULTS: In 26 of the 30 patients with known systemic amyloidosis, amyloid deposits were identified on LSG biopsy (sensitivity of 86%). In 1 of the remaining patients, amyloid deposits were identified on LSG biopsy and systemic amyloidosis was confirmed by abdominal fat biopsy and 123I-labeled SAP scintigraphy. CONCLUSION: This study emphasizes the high sensitivity of LSG biopsy in the diagnosis of amyloidosis, even in the absence of oral symptoms.

Adult↗
PubMed1993

Stimulation of the secretion of latent cysteine proteinase activity by tumor necrosis factor alpha and interleukin-1.

OBJECTIVE: Cultured synovial fibroblast-like cells from 3 patients with rheumatoid arthritis (RA) and 3 patients with osteoarthritis (OA) were evaluated for their potential to secrete cysteine proteinases spontaneously and after stimulation by tumor necrosis factor alpha (TNF alpha) or interleukin-1 (IL-1). METHODS: Culture media and cell lysates were analyzed before and after high performance liquid chromatography (HPLC) using the enzymatic substrate, Z-Phe-Arg-AMC, and by immunoblotting with anti-cathepsin B antiserum. Immunolocalization of cathepsin B was studied on cell monolayers. RESULTS: Latent cysteine proteinase activity was found to be secreted spontaneously by cultured synovial fibroblast-like cells. This activity was increased after treatment with either TNF alpha or IL-1. Stimulated protease activity was eluted by HPLC at a peak coincident with that of purified cathepsin B. By immunoblot, cell supernatants contained a 43-kd form of cathepsin B, while cell lysates contained a 30-kd form, consistent, respectively, with cathepsin B before and after cleavage of its propeptide. An intracellular increase in cathepsin B after treatment with TNF alpha was also seen with immunohistochemical studies. CONCLUSION: TNF alpha (in the 6 cases studied) and IL-1 (in 4 cases) stimulated the secretion of a latent cysteine proteinase activity from synovial fibroblast-like cells, which appears to represent primarily cathepsin B.

Arthritis, Rheumatoid↗
PubMed1993

[Is the expression of TNF-alpha and cell adhesion molecules a marker of development of rheumatoid vasculitis?].

TNF-alpha, ICAM1, VCAM1, ELAM, CD44 and DR expression were studied (indirect immunoperoxydase methods) on labial salivary gland sections in 5 patients with proven rheumatoid vasculitis (before and after treatment), 5 patients with RA and 5 normal controls. TNF-alpha and cell adhesion molecules were particularly expressed in vasculitic areas of patients with systemic vasculitis and only before the onset of the treatment.

Biomarkers↗
PubMed1993

High incidence of lymphoid infiltration on labial salivary gland biopsy in non-Hodgkin's lymphomas: clinical implications.

Sjögren's syndrome (SS) is characterized by an increased risk of developing a non-Hodgkin's lymphoma (NHL). We performed labial salivary gland biopsy (LSGB) in 103 patients with untreated NHL, negative for human immunodeficiency virus. Median age was 58 years (range 21-79) and M/F 1.3. Using the Working Formulation, 37 patients had low-grade NHL and 66 had intermediate- or high-grade NHL. Dense lymphocytic infiltration (positive focus score 3 or 4) was found in 28 patients. 10 (35%) of these 28 patients fulfilled criteria for possible SS. 15/28 patients had an identical monotypic infiltrate on LSGB and NHL tissue (including two of the 10 patients with criteria for SS). The significance of the lymphoid infiltrate of LSGB was unknown in the five remaining patients with positive focus score. Significant correlations were found between positive focus score and presence of two or more extranodal sites of disease (P = 0.02), impaired performance status (P = 0.004), splenomegaly (P = 0.05), increased gammaglobulin level (P = 0.03), and beta 2 microglobulin (P = 0.004). Considering intermediate- or high-grade NHL, we found significant correlation between positive focus score and unfavourable prognosis according to the two Dana Farber Cancer Institute indexes (P < 0.04), to the LNH-84 index (P = 0.05), and to the international index (P = 0.003). In conclusion, systematic evaluation of LSGB in 103 patients with NHL found lymphoid infiltration in 28% of them, but possible SS could be considered in only 10%. This lymphoid infiltration, though not correlated with any particular histological subtypes, was associated with unfavourable clinical prognostic factors, especially in intermediate- or high-grade NHL.

Adult↗
PubMed1993

Segregation of eosinophil proteins in alveolar macrophage compartments in chronic eosinophilic pneumonia.

BACKGROUND: The objective was to characterise the process and consequences of eosinophil activation and lysis in patients with chronic eosinophilic pneumonia and to compare them with those in patients with eosinophil pulmonary infiltrates from other causes. METHODS: Cells from bronchoalveolar lavage fluid of four patients with chronic eosinophilic pneumonia and four patients with eosinophilic infiltrates associated with Sjögren's syndrome, drug hypersensitivity pneumonia, postradiotherapy fibrosis, and pulmonary disease associated with graft versus host disease were studied ultrastructurally and with immunogold labelled antibodies directed against eosinophil proteins: major basic protein, eosinophil cationic protein, and Charcot-Leyden crystal protein. The concentration of eosinophil cationic protein was also measured in bronchoalveolar fluid. RESULTS: In the four patients with chronic eosinophilic pneumonia, ultrastructural studies demonstrated numerous lysed eosinophils. Further, three released eosinophil proteins were detected in distinct cytoplasmic structures in alveolar macrophages. These features were not found in the four patients with eosinophilic pulmonary infiltrates from other causes. CONCLUSION: Eosinophils in chronic eosinophilic pneumonia show signs of activation with release of eosinophil proteins. The appearance of three of these eosinophil proteins in different macrophage compartments suggests that macrophage uptake, with or without intracellular transport of released eosinophil proteins, involves separate mechanisms. This interaction does not lead to macrophage lysis, however, and one or more of these eosinophil proteins might directly affect macrophage function.

Adult↗
PubMed1993

Expression of human mucin genes in respiratory, digestive, and reproductive tracts ascertained by in situ hybridization.

In recent years considerable advances have been made in our knowledge of the peptide moiety of human mucins through cDNA cloning. In many diseases disorders in mucin biosynthesis are observed, which result either from changes in the synthesis of the carbohydrate side chains or from differences in the relative expression of the different apomucins, each of which may affect physical properties of the viscous gel. We describe in situ hybridization studies on healthy human mucosae with five different oligonucleotide probes corresponding to each of the human genes known to date that encode secreted mucins, i.e., MUC 2, 3, 4 (HGM nomenclature) and 5B, 5C (proposed name). These genes present a nucleic tandem repeat organization. The choice of oligonucleotide probes was made to amplify the signal by hybridization of many small probes on the same mRNA molecules. A characteristic pattern of mucin gene expression was observed for each mucosa.

Base Sequence↗
PubMed1992

[Gold salt deposits in the conjunctiva in rheumatoid arthritis after gold therapy. A systematic study of 15 biopsies].

Ocular abnormalities have long been recognized as a potential adverse effect of gold therapy in patients with rheumatoid arthritis. Clinical symptoms and ocular tissue lesions possibly related to use of gold therapy were routinely evaluated in eleven patients. There were few clinical manifestations: only one patient had typical accumulation of gold in the anterior crystalloid. In contrast, routine ultrastructural and microprobe studies of conjunctival biopsy specimens disclosed accumulation of gold salts in every case. Gold was visible as aurosomes in the conjunctival macrophages. Aurosomes were seen in patients treated for as little as one month, occurred even with low doses (0.3 g), and were still visible after several years. Duration of accumulation can be roughly estimated on the basis of the morphologic appearance of aurosomes which are lamellar after a few weeks of gold therapy and rod-shaped beyond one month.

Adult↗
PubMed1992

Interleukin 5 messenger RNA expression by eosinophils in the intestinal mucosa of patients with coeliac disease.

Interleukin 5 (IL-5), the major factor involved in eosinophil differentiation, is produced by T cells or mast cells. In the present study, we found that eosinophils infiltrating the mucosa of four patients with active coeliac disease also express the IL-5 mRNA. No positive signal was obtained in normal duodenum tissues and in the cell infiltrate from patients submitted to gluten restriction. The identification of labeled mucosal cells as eosinophils relied on their typical morphology. Moreover, highly purified blood eosinophils from three out of four patients with eosinophilia were also strongly labeled with the IL-5 antisense but not with the corresponding sense probe. Together, these results suggest that eosinophils have the capacity to synthesize IL-5, which could contribute to paracrine interactions with T and B cells and, in autocrine fashion, locally participate, through binding to the IL-5 receptor, to eosinophil differentiation and activation. These data might have implications not only in the pathology of coeliac disease but also in other diseases associated with eosinophil infiltration.

Celiac Disease↗
PubMed1992

Immunopathological study of eosinophils in eosinophilic granuloma of bone: evidence for release of three cationic proteins and subsequent uptake in macrophages.

Eosinophils from two patients with eosinophilic granuloma of bone (EGB) were studied by combined immunohistochemical and immuno-ultrastructural methods with antibodies directed against three eosinophil granule proteins: major basic protein, eosinophil cationic protein, and eosinophil peroxidase. Immunohistostaining showed the presence and distribution of large numbers of eosinophils in the granuloma. Immuno-ultrastructural methods showed alterations of eosinophil fine structure associated with some steps in the release of granule proteins. No granule extrusion was seen, but rather cationic proteins diffused within cytoplasmic tubulo-vesicular structures. Furthermore, the three granule proteins were found within phagolysosomes of surrounding macrophages, suggesting an interaction between eosinophils and phagocytic cells at the destructive stage of EGB.

Adolescent↗
PubMed1992

Activated eosinophils in adult coeliac disease: evidence for a local release of major basic protein.

The eosinophil population is increased in the jejunal mucosa of patients with coeliac disease. Eosinophils may participate in the mucosal damage by releasing their granule components that have cytotoxic properties such as eosinophil cationic protein (ECP) and major basic protein (MBP). This study aimed to assess the presence of ECP and MBP in the jejunal mucosa of 10 adult patients with active coeliac disease who presented with villous flattening. Endoscopic jejunal biopsy specimens were obtained from macroscopically flattened jejunal mucosa and were processed for ultrastructural study and immunogold labelling using anti-MBP, anti-ECP, and anti-IgA antibodies. Numerous eosinophils were found in the upper part of the lamina propria and showed two types of morphological change: some were lytic and others exhibited ultrastructural signs of activation, containing altered granules with fading of the central core. IgA plasma cells were intermingled with eosinophils and had dense deposits on the external side of their cytoplasmic membrane. MBP was detected in central cores of granules but also diffusely in their matrix and in tight association with dense extracellular deposits. Conversely, ECP was detected only in the matrix of eosinophil granules. This study showed that numerous eosinophils are in an activated state in the mucosa of patients with active coeliac disease and release cytotoxic proteins such as MBP, which could contribute to the mucosal damage. The observation that eosinophils and IgA plasmocytes were closely associated in the mucosa supports a role for IgA in eosinophil recruitment and activation in coeliac disease.

Adolescent↗
PubMed1992

Increased intestinal permeability in active pulmonary sarcoidosis.

Altered permeability of the gut is a well-described feature in Crohn's disease. Because of pathologic similarities between Crohn's disease and sarcoidosis, we initiated this study to evaluate the permeability of the gut mucosal lining in patients with pulmonary sarcoidosis. A group of 18 patients with biopsy-proven pulmonary sarcoidosis (active n = 8, inactive n = 10) were included in the study. Control groups included 22 patients with Crohn's disease (active n = 12, inactive n = 10), nine untreated patients with recent pulmonary tuberculosis, six patients with coal worker's pneumoconiosis (CWP), eight patients with idiopathic pulmonary fibrosis (IPF), and 16 healthy subjects. All were nonsmokers. The 24-h urinary excretion of 100 microCi 51Cr-ethylenediaminetetraacetic acid (51Cr-EDTA) was used to test the intestinal permeability (IP). As previously demonstrated, patients with active Crohn's disease demonstrated a dramatic increase in IP (7.7 +/- 1.4%) that was clearly reduced in inactive CD (2.34 +/- 0.54%). Patients with active pulmonary sarcoidosis exhibited a marked increased IP to 51Cr-EDTA (4 +/- 0.54%), which was not found in patients with inactive sarcoidosis (1.6 +/- 0.17%). IP was normal in patients with pulmonary tuberculosis (1.03 +/- 0.25%), CWP (2.1 +/- 0.54%), and IPF (1.9 +/- 0.33%) and did not differ from the control group (1.76 +/- 0.23%). In addition, in 6 patients with active pulmonary sarcoidosis, the concentrations of albumin and hyaluronan were measured in jejunal perfusion fluid and compared with those obtained from 10 patients with active Crohn's disease and 16 control subjects.(ABSTRACT TRUNCATED AT 250 WORDS)

Albumins↗