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M C Bene

Publications and source records attributed to M C Bene.

At least 19 recordsLinked to original sources
PubMed2001

CD9 and HLA-DR expression by crevicular epithelial cells and polymorphonuclear neutrophils in periodontal disease.

BACKGROUND, AIMS: The composition of gingival crevicular fluid (GCF) is likely to reflect inflammatory modifications that take place in the gingiva during periodontal diseases. METHOD: In this study, GCF was collected at 3 different sites from 23 periodontal patients. The sites were assessed to be healthy, presenting gingivitis or periodontitis. 10 healthy individuals without any form of periodontal disease formed the control group and were sampled at one site each. The cell content of GCF was collected using Durapore Millipore strips, and 2 types of cells were studied: epithelial cells (EC) and polymorphonuclear neutrophils (PMN). The expression of CD9 and HLA-DR within or on the surface of these cells was studied in immunofluorescence on cytospin smears. RESULTS: Both CD9 and HLA-DR expression on EC differed significantly from control subjects, and the latter decreased according to the severity of the pathology. None of the PMN found in controls expressed CD9 or HLA-DR. However, in periodontal patients, the expression of HLA-DR within PMNs was detectable and increased according to the severity of lesions. CD9 expression on PMNs also increased with inflammation. CONCLUSION: This study shows that clinically healthy sites of periodontal patients already present signs of immunological activation characterised by a down modulation of HLA-DR expression on EC and an upregulation of these 2 molecules in PMN.

Adolescent↗
PubMed2001

[Sinobronchial syndrome].

The sinobronchial syndrome consists of chronic sinusitis and chronic nonspecific inflammation of the lower airways, typically chronic bronchitis, bronchiectasis and diffuse panbronchiolitis. This airway disease of unknown etiology is not related to smoking. It is common in Japan and is poorly described in western countries. We report a case in a non-Asian patient. The known efficacy of long-term low-dose erythromycin therapy justifies careful diagnosis of sinobronchial syndrome in patients of non-Asian ethnic origin.

Anti-Bacterial Agents↗
PubMed2000

[Polyclonal T lymphocyte proliferation in drug lymphocyte activation test].

BACKGROUND: We examined the clonality of the specific T cell reaction activated with specific drug antigens in patients with a positive lymphocyte activation test. PATIENTS AND METHODS: Ten patients were investigated. Their clinical features suggested drug allergy. Six weeks after a skin reaction, skin tests and lymphocyte activation tests were run. For each lymphocyte activation test, we explored the clonality of the T cell proliferation by examining the VJ rearrangement of the TCR gamma locus using polymerase chain reaction and denaturing gradient gel electrophoresis. RESULTS: All samples gave positive lymphocyte activation tests proving in vitro polyclonal T cell proliferation in reaction to a drug. There was no difference in clonality between the pilot lymphocyte activation test and the lymphocyte activation test after stimulation with phytohemagglutinin or with the drug antigen. DISCUSSION: Our findings show that in vitro T cell proliferation induced by a specific drug antigen as disclosed by the lymphocyte activation test is a polyclonal or oligoclonal cell proliferation. This lack of production of a preferential T clone in a T cell-mediated immune drug reaction implies that many T lymphocytes can recognize the antigen and be stimulated by the same drug.

Adult↗
PubMed1999

Enhanced expression of L-selectin on peripheral blood lymphocytes from patients with IgA nephropathy.

To investigate the homing characteristics of T and B lymphocytes which could explain the abnormal partition of IgA-producing cells in tonsils and bone marrow from patients with IgA nephropathy (IgAN), the expression of leucocyte adhesion molecules (CD11a, CD29, CD49d, CD62L, CD31) was assessed using flow cytometry on peripheral blood leucocytes from patients with biopsy-proven IgAN and controls. Higher proportions of T and B lymphocytes expressing higher amounts of L-selectin, as well as higher proportions of B cells expressing more CD31 were evidenced in IgAN patients. Conversely, serum levels of sCD62L were not different from controls, but significantly higher than serum levels in patients suffering from other renal diseases. We hypothesize that this over-expression of CD62L and CD31 may be involved in an enhanced efficiency of lymphoid cells homing to lymphoid tissues in this disease.

Adult↗
PubMed1998

The reliability and specificity of c-kit for the diagnosis of acute myeloid leukemias and undifferentiated leukemias. The European Group for the Immunological Classification of Leukemias (EGIL).

We document findings on c-kit (CD117) expression in 1,937 pediatric and adult de novo acute leukemia cases, diagnosed in five single European centers. All cases were well characterized as to the morphologic, cytochemical, and immunologic features, according to the European Group for the Immunological Classification of Leukemias (EGIL). The cases included 1,103 acute myeloid leukemia (AML), 819 acute lymphoblastic leukemia (ALL), 11 biphenotypic acute leukemia (BAL), and 4 undifferentiated (AUL). c-kit was expressed in 741 (67%) AML cases, regardless of the French-American-British (FAB) subtype, one third of BAL, all four AUL, but only in 34 (4%) of ALL cases. The minority of c-kit+ ALL cases were classified as: T-cell lineage (two thirds), mainly pro-T-ALL or T-I, and B lineage (one third); cells from 62% of these ALL cases coexpressed other myeloid markers (CD13, CD33, or both). There were no differences in the frequency of c-kit+ AML or ALL cases according to age being similar in the adult and pediatric groups. Our findings demonstrate that c-kit is a reliable and specific marker to detect leukemia cells committed to the myeloid lineage, and therefore should be included in a routine basis for the diagnosis of acute leukemias to demonstrate myeloid commitment of the blasts. c-kit expression should score higher, at least one point, in the system currently applied to the diagnosis of BAL, as its myeloid specificity is greater than CD13 and CD33. Findings in ALL and AUL suggest that c-kit identifies a subgroup of cases, which may correspond to leukemias either arising from early prothymocytes and/or early hematopoietic cells, both able to differentiate to the lymphoid and myeloid pathways.

Acute Disease↗
PubMed1998

Maturation of B cells in the lamina propria of human gut and bronchi in the first months of human life.

Little is known of the maturation of the mucosae-associated lymphoid tissue (MALT) in man, because, for ethical reasons, tissues from newborns are not easy to obtain. We used the opportunity provided by autopsies systematically performed in infants who died of Sudden Infant Death Syndrome (SIDS) to study the maturation of the MALT after birth. Gut and bronchus samples of 90 infants from postpartum to 90 months and who died from SIDS were collected and studied by histological and immunofluorescence examination. Plasma cells, absent at birth, appeared within a few hours after birth and initially were of the IgM isotype. IgA plasma cells appeared at 12 days. These cells were first observed in gut and later in bronchi, indicating that maturation of the gut precedes that of bronchi. The number of plasma cells increased rapidly over time and IgA plasma cells became predominant after 3 weeks in the gut and 6 weeks in bronchi. At birth, only small IgM bearing B-cell foci were seen and organized germinal centers appeared to develop over a few days, first in the gut and only later in bronchi. These results confirm that, in man, the MALT organization at birth is still in its fetal form and that maturation depends on intestinal challenges and evolves over several weeks before IgA becomes the predominant isotype secreted.

B-Lymphocytes↗
PubMed1998

Activation of epithelial cells in gastritis.

BACKGROUND: Helicobacter pylori is now recognised to be the major cause of antral gastritis and a risk factor for further development of gastric cancer. This infection results in local inflammation and a modification of gastric mucosal epithelial cell characteristics. Systematic investigation for the expression of the secretory component by gastric epithelium in a personal historical series of biopsy specimens showed the expression of this activation marker in 38% of the cases, 19% also showing clear signs of H. pylori infection. AIMS: To further appreciate the activation of epithelial cells in the chronic gastric inflammation associated with H. pylori infection and other types of gastritis without consideration of the grade of gastritis. METHODS: Punch gastric biopsies from 36 patients (10 patients with confirmed H. pylori gastritis, 16 patients with non-H. pylori gastritis and 10 controls) were tested for the expression of ICAM-1/CD54, HLA-DP, -DQ, -DR, secretory component and bcl-2 by immunofluorescence. RESULTS: Up-regulation of most markers was observed both in H. pylori and non-H. pylori gastritis, although secretory component, CD54 and DP expression was more closely associated with H. pylori gastritis. CONCLUSION: H. pylori infection appears to activate gastric epithelial cells more strongly than other types of gastritis. This suggests an active relationship between this bacterium and epithelial cells. Investigation of the up-regulationship between this bacterium and epithelial cells. Investigation of the up-regulation of secretory component, ICAM-1/CD54 or DP in gastric biopsies may serve as extensive markers in search of H. pylori gastric infections.

Adult↗
PubMed1998

Evaluation of human sperm acrosome reaction and viability by flow cytometry.

We report in this work a quantitative procedure developed to evaluate the acrosomal reaction and vitality of human spermatozoa, with three color staining simultaneously. Twenty normal human sperm were labeled with GB24 monoclonal antibody, a fluorescein isothiocyanate conjugated lectin and propidium iodide (supravital stain). Four conjugated lectins were investigated: WGA, Con-A, PNA and UEA-1. Acrosome reaction was induced with calcium ionophore A-23187. Analyses were made by flow cytometry and electron microscopy. A high percentage of spermatozoa that stained with propidium iodide was found. The results of four lectins show an interaction between GB24 and lectin binding. Significant differences of fluorescence index were obtained between the samples with calcium ionophore A-23187 and the samples without it. The WGA-GB24 association shows an independent behavior and this may depend on the fact that WGA binds to the cytoplasmic membrane of human spermatozoa and GB24 antibody bind inner acrosome membrane. Using Con-A, PNA and UEA-I a crowded staining is likely to occur because these lectins and GB24 antibody mainly bind to acrosome membranes, and our results then show a close relation.

Acrosome Reaction↗
PubMed1997

Coexpression of CD40 and class II antigen HLA-DR in Graves' disease thyroid epithelial cells.

In Graves' disease, thyroid epithelial cells abnormally express HLA-DR Class II molecules in the vicinity of lymphocyte infiltrates, suggesting that lymphocyte proliferation is sustained by the appropriate presentation of antigenic material. The ability of thyroid epithelial cells to provide the necessary second signals has however not been documented. The expression of HLA-DR, CD40, CD40L, CD80, and CD28 was investigated on thyroid samples from 30 patients (Graves' disease, n = 16; benign toxic adenoma, n = 8; multinodular goiter, n = 6). Apoptotic cells were searched for using the TUNEL method. CD40 appeared to be coexpressed with HLA-DR in Graves' disease patients samples and in two control samples also containing lymphoid infiltrates. Almost no apoptotic cells were found. These data suggest that thyroid epithelial cells from Graves' disease patients have the ability to successfully present autoantigens. The near absence of apoptotic cells in surrounding lymphoid infiltrates is in keeping with this efficient provision of a rescue second signal.

Adolescent↗
PubMed1997

Specific humoral immune responses in 12 cases of food sensitization to sesame seed.

BACKGROUND: Hypersensitivity to sesame seeds is becoming increasingly frequent, probably owing to the larger use of this compound in international food. OBJECTIVES: This study investigated serum responses of 12 sesame sensitized patients (seven with food allergy, five with food sensitization), to a sesame protein extract, and attempted at identifying sesame major antigens. METHODS: Sesame protein extracts were prepared from black, white and brown sesame seeds. Electrophoretic analysis showed similar protein patterns in the three extracts, and proper preservation of the proteins integrity. The brown sesame extract was used to set-up an ELISA assay and measure serum levels of antisesame IgG, IgA, IgM and IgE in 12 samples from sesame-sensitized individuals and six controls. It also allowed to perform western blot analyses in order to investigate the molecular weight of sesame proteins recognized by IgG, IgA and IgE. RESULTS: Nineteen protein bands were observed upon polyacrylamide gel electrophoresis of the sesame protein extracts. Using this whole extract in ELISA, significant antisesame IgG, IgA and IgE-responses were observed in the serum of sensitized individuals, different from the lower signals obtained with control samples. Western blot analysis demonstrated highly polymorphic IgG and IgA responses and a more restricted IgE response pattern, suggesting that two proteins, respectively, 14 kDa and 25 kDa are mostly involved in sesame IgE-dependent hypersensitivity, the 25 kDa band presenting several characteristics of a major allergen. CONCLUSIONS: This study reports novel information on the possible involvement of a 25 kDa sesame protein in IgE-dependent hypersensitivity to sesame seeds.

Adult↗
PubMed1996

Investigation of activation markers demonstrates significant overexpression of the secretory component on salivary glands epithelial cells in Sjögren's syndrome.

Labial salivary glands biopsies (LSG) performed to support clinical anomalies suggestive of Sjögren's syndrome (SS) sometimes fail to confirm the diagnosis. Here we investigated whether epithelial activation markers could provide further information. Frozen cut sections of LSG from 40 patients, including 23 confirmed SS, were examined in immunofluorescence for the expression of HLA class II molecules, the protector of apoptosis bcl-2, the intercellular adhesion molecule 1 (ICAM-1) and secretory component (SC). Class II molecules were highly expressed on epithelial cells in SS patients (DR > DP > DQ). Bcl2 was expressed in infiltrating cells which were more numerous in the group of SS patients. ICAM-1 was present on endothelial and infiltrating cells of a few patients in both groups. Epithelial cells produced SC in 83% of SS patients samples vs four cases of non-SS patients (P = 0.0002). Investigation of the expression of SC on glandular epithelial cells could therefore be proposed as a marker of SS.

Adult↗
PubMed1995

Isoelectric restriction of human immunoglobulin isotypes.

The partition of human serum immunoglobulins along a pH gradient of ampholynes was investigated using the recently developed method of preparative isoelectrofocusing. Each isotype was demonstrated to display a specific pI range, with limited overlapping. IgA appear to be the most acidic serum immunoglobulins while IgG are clearly basic.

Adolescent↗
PubMed1995

Altered partition of T cell subsets in the peripheral blood of healthy workers exposed to flour dust.

Occupational exposure to organic compounds can induce obvious immunological disorders or more subtle modifications. We investigated peripheral blood lymphocyte subsets in 34 bakers and 82 millers exposed to wheat flour dust, and 51 salt factory workers. Significantly decreased levels of CD4+, CD8+, CD57+ and CD8+/57+ cells were noted in mill workers, and of CD57+ cells in bakers. CD29+ and CD4+/CD29+ cells were significantly lower in millers, CD4+/CD45RA+ cells higher in all exposed workers. The lower numbers of positive cells noted in millers appeared associated to significantly higher (p < 0.001) levels of CD29 and CD45RA expression as measured by fluorescence intensity. These data are opposite to those previously reported in asthmatic workers exposed to flour dust. Since the individuals tested here were clinically healthy, the alterations of T-cell subsets observed could be interpreted as a successful attempt at immunoregulation maintaining homeostasis.

Antigens, CD↗
PubMed1995

Serum anti-dextran antibodies in IgA nephropathy.

Abnormally high humoral responses have been described in IgA nephropathy (IgAN), towards antigens commonly involved in infectious events or food intolerance. Here we report a comparative analysis of humoral responses to a common environmental antigen, dextran B 512, present both in nonpathogenic microorganisms and normal diet. Dextran-specific IgG, IgA and IgM were assayed using an ELISA method in serum samples from 121 patients with IgAN, 40 controls and 32 patients with biopsy-proven renal diseases different from IgAN. Among the latter, 17 were transplant recipients. Anti-dextran IgG antibodies were found significantly (p < 0.05) more frequently and at higher levels in IgAN patients than in patients with other renal diseases. Anti-dextran IgA were at significantly (p < 0.05) higher levels in IgAN patients than in controls or untransplanted NIgAN patients. However, similarly elevated levels of anti-dextran IgA were found in IgAN patients and transplanted patients with other renal diseases. These data confirm that IgA and IgG responses towards common antigens are elevated in IgAN, possibly as a consequence of the pathogenesis of this disease rather than because of renal impairment. Moreover, since the same degree of dysregulation was noted in the control group of transplanted patients whose initial diagnosis was not IgAN, these data favour the hypothesis of a global dysregulation of the IgA system in IgAN, yielding enhanced humoral immune responses to possible pathogens and diet antigens.

Adult↗