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N Genetet

Publications and source records attributed to N Genetet.

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

Immunological study in primary intestinal lymphangiectasia.

Primary intestinal lymphangiectasia is a rare congenital condition associated with protein-losing enteropathy. Hypogammaglobulinemia and lymphopenia secondary to this condition are frequent but infectious complications are not. So far few immunological studies have been made in these patients. We report here the results of such a study carried out in two adolescents. Both patients presented with a dramatic decrease in serum gammaglobulins, especially IgG and IgA, and in peripheral blood lymphocytes, especially CD4 T helper cells. From a functional standpoint, the proliferative response to certain mitogens was reduced. A decrease in in vitro production of immunoglobulins by B lymphocytes may be due to a faulty T/B cell cooperation. Histological examination of duodenal biopsy specimens revealed a decreased number of intraepithelial lymphocytes. Colonoscopy revealed nodular lymphoid hyperplasia in the terminal ileum, confirmed by endoscopic biopsy. The role of these abnormalities in the development of infectious complications and lymphoma is underscored.

Adolescent↗
PubMed1992

Interferon production in severe hemophiliacs with and without HIV antibodies.

The interferon (IFN) system, both serum IFN levels and the in vitro IFN production, was investigated in 38 clinically asymptomatic multitransfused hemophiliacs, half positive and half negative for HIV antibodies. In most patients, no circulating IFN was detected; similar levels of IFN-alpha were obtained after peripheral blood mononuclear cell (PBMC) stimulation with Sendai virus both in hemophiliacs and controls, while production of IFN-gamma following stimulation with phytohemagglutin (PHA) was diminished in a large number of patients irrespective of their HIV serology. These data indicate that the deficiency in IFN-gamma generation is not only related to HIV contamination but may be a direct consequence of the chronic antigenic stimulation through Factor VIII concentrates.

HIV Seropositivity↗
PubMed1992

Surface markers in adult acute myeloblastic leukemia: correlation of CD19+, CD34+ and CD14+/DR--phenotypes with shorter survival. Groupe d'Etude Immunologique des Leucémies (GEIL).

The immunophenotype of blast cells was investigated in a multicentric study of 154 adult acute myeloblastic leukemias (AMLs). A panel of 27 monoclonal antibodies (MoAbs) was tested in indirect immunofluorescence. Expression of CD14 (UCHM1), CD19 (SB4), CD36 (OKM5), and HLA-DR were associated with higher mean leucocyte counts. CD14 expression correlated with low hemoglobin level and the absence of CD33 (MY9) with low platelet counts. Extramedullary disease was associated with CD16 (Leu11b) and HLA-DR antigen positivity. The study of relationships between surface markers and FAB criteria confirmed the predominant expression of CD14 in the M5 sub-group (p less than 0.000001) and the association of CD19 and CD36 with monocytic M4/M5 subgroups (respectively p less than 0.00002 and p less than 0.000001). All patients received an induction therapy including an anthracycline and cytarabine. The median follow-up was 13 months. The achievement of complete remission (CR) was inversely correlated with CD34 (B13C5) and CD19 expression: CR was obtained in 31 of 59 (53%) CD34-positive AML versus 64 of 75 (85%) CD34-negative cases (p less than 0.0001) and 11 of 24 (46%) CD19-positive versus 95 of 122 (78%) CD19-negative cases (p less than 0.01). In univariate analysis, a longer survival was associated with CD33 expression and the combined phenotypes CD36+/CD19- and CD16+/CD14-. Conversely, the CD18(IOT18)+/CDw65(VIM2)- phenotype was related to shorter survival. The expression of CD19, of CD34, and of the combined phenotype CD14+/DR--correlated with shorter survival as demonstrated both in univariate and multivariate analysis (p less than 0.03 in each case in multivariate analysis).

Antigens, CD↗
PubMed1991

Sertoli cells are the site of interleukin-1 alpha synthesis in rat testis.

To elucidate the cellular origin of interleukin-1 (IL-1) in the mammalian testis, we assayed IL-1 activity in culture media of Sertoli cells collected from rats at 20, 35 and 45 days of age as well as in culture media of interstitial, peritubular and germ cells from adult rats. IL-1 was detected in Sertoli cell culture media isolated from 35- and 45-day-old rats. At 45 days approximately twice as much IL-1 was produced than at 35 days. In contrast, IL-1 activity was not detected in 20-day-old rat Sertoli cell culture media nor in interstitial, peritubular and germ cell culture media. The Sertoli cell IL-1 activity was specifically neutralized by an IL-1 alpha antiserum. It is concluded that Sertoli cells produce IL-1 alpha and that this production increases during sexual maturation.

Animals↗
PubMed1991

Does peripheral blood T-lymphocyte population distribution in sarcoidosis provide a prognostic clue?

In its pulmonary form, sarcoidosis generally resolves spontaneously, but it may lead to fibrosis of the lung. The clinical, radiological and functional tests, as well as activity markers such as the serum angiotensin converting enzyme, intrathoracic uptake of 67Gallium and the cytological data provided by bronchoalveolar lavage are only the expressions at any given time of a disease which is constantly progressing and only partly express its evolutive potential. The authors studied the distribution of T-lymphocyte subsets in the peripheral blood and from bronchoalveolar lavage. 32 patients were included in the study. They were suffering from acute or chronic sarcoidosis of the mediastinum and lungs and were divided into 2 groups according to clinical, radiological and pulmonary function criteria; Group A (n = 19) included regressive forms (minimum follow up 2 years) and group B (n = 13) the progressive untreated forms. Lymphopenia with a decrease in the percentage of CD3 cells was found in both groups. The percentage of CD4 cells is significantly lower in group B (28 +/- 11%) than in group A (45 +/- 8%) (p < 0.01) or in the control population (46 +/- 8%) (p < 0.01). The percentage of CD8 cells is higher in group B (30 +/- 8%) than in group A (18 +/- 6%). This results in a CD4/CD8 ratio which is significantly reduced in group B (1 +/- 0.5) when compared with group A (2.72 +/- 0.8) (p < 0.01) and the control group (2.17 +/- 0.8) (p < 0.01), the difference between group A and the controls being minimal.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1988

Interferon production in severe hemophiliacs with and without HIV antibodies.

The interferon (IFN) system, both serum IFN levels and the in vitro IFN production, was investigated in 38 clinically asymptomatic multitransfused hemophiliacs, half positive and half negative for HIV antibodies. In most patients, no circulating IFN was detected; similar levels of IFN-alpha were obtained after peripheral blood mononuclear cell (PBMC) stimulation with Sendai virus both in hemophiliacs and controls, while production of IFN-gamma following stimulation with phytohemagglutin (PHA) was diminished in a large number of patients irrespective of their HIV serology. These data indicate that the deficiency in IFN-gamma generation is not only related to HIV contamination but may be a direct consequence of the chronic antigenic stimulation through Factor VIII concentrates.

HIV Seropositivity↗
PubMed1988

Induction of angiotensin converting enzyme in cultured human monocytes by a factor present in the bronchoalveolar lavage fluid of sarcoidosis patients.

Human peripheral blood monocytes synthesize a low level of angiotensin converting enzyme (ACE) when cultured in vitro for six days. If cell-free bronchoalveolar lavage fluid from sarcoidosis patients was included with the monocytes during culture, the monocyte ACE level increased significantly in a dose dependent manner. In contrast, the cell-free bronchoalveolar lavage fluid from control subjects and patients with idiopathic pulmonary fibrosis or hypersensitivity pneumonitis raised basal monocyte levels little, if at all. These results suggested that sarcoid lavage fluid contains a soluble ACE-inducing factor (AIF) that was absent or present in much lower concentrations in the bronchoalveolar lavage fluid of the other patients studied. Initial attempts to characterize this AIF indicated an apparent molecular weight of greater than 5000 daltons as determined by Amicon ultrafiltration. The AIF was stable to heating at 56 degrees for 1 hour. This finding demonstrated that lavage ACE was not responsible for the AIF activity since lavage ACE is inactivated under these conditions. Gamma-interferon (macrophage-activating factor) was also eliminated as the agent responsible for AIF activity since gamma-interferon decreased rather than increased monocyte ACE. In summary, bronchoalveolar lavage fluid from sarcoid patients contains a soluble factor (AIF) that induces ACE in cultured monocytes. Action of this factor in vivo may be responsible for the increased ACE levels seen in the monocyte-derived epithelioid granuloma cells of sarcoidosis.

Adult↗
PubMed1988

Does immunodeficiency in uremic patients promote dialysis-related amyloidosis?

The present study was undertaken to evaluate the immune function of 5 hemodialysis patients with dialysis-related amyloidosis as compared to 6 without, both groups having a dialytic age from 7 to 21 years, and 5 healthy controls. We investigated serum levels of immunoglobulins (IgG, IgA, IgM), made skin tests and measured peripheral lymphocyte subsets using monoclonal antibodies. 1) The absolute numbers of T3, T4 and T8 cells were significantly lower in hemodialysis patients than controls and T3, T4 cells were lower in patients with amyloidosis than in those without: T3 (m +/- SD/microliter), 387 +/- 253 vs 744 +/- 207 (p = 0.03); T4, 262 +/- 115 vs 589 +/- 297 (p = 0.04). 2) Serum levels of IgG and IgM were significantly lower in patients with amyloidosis than in the others: IgG (m +/- SD, g/l), 10.2 +/- 1.4 vs 15.4 +/- 3.2 (p less than 0.001); IgM, 0.65 +/- 0.28 vs 1.65 +/- 0.37 (p less than 0.001). 3) Delayed hypersensitivity studied by skin tests showed less than 3 positive antigens in 4/5 patients with amyloidosis against 1/6 patients without. These data suggest there is a marked defect of T-cell help in uremic patients with dialysis-related amyloidosis.

Adult↗
PubMed1987

Murine monoclonal antibody suitable for use as an Rh reagent, anti-e.

The production by the hybridoma technique of a monoclonal antibody which behaves as an anti-e agglutinin is described. A reagent was made from ascitic fluid diluted in RPMI 1640 culture medium and bovine serum albumin. All red blood cells bearing the e antigen were agglutinated; no reactivity was recorded with untreated EE red cells suspensions. However, cross-reactivity was observed with enzyme-pretreated EE cells. The characteristics of this monoclonal antibody are described and are in accordance with the standard references.

Animals↗
PubMed1987

Immunological parameters in Graves' disease: are they useful for indication and monitoring of antithyroid drug treatment?

This paper reviews the available published data on studies of a correlation between the presence or intensity of measurable immunological abnormalities or markers in Graves' disease and the outcome after a course of antithyroid drug. The following parameters are discussed: circulating anti-thyroid-stimulating hormone receptor antibodies; antitubulin antibodies; human lymphocyte antigens, and repartition of T-lymphocyte subsets. At the present time no single parameter has any real practical value for individual patients either to indicate or monitor antithyroid drug therapy. The more useful information remains the anti-thyroid-stimulating hormone receptor level at the end of treatment which, if elevated, is predictive of relapse. Several areas of research, however, appear promising.

Antithyroid Agents↗
PubMed1987

[Anomalies of cellular immunity in Graves' disease treated by synthetic antithyroid drugs: effects on prognosis].

The involvement of humoral immunity mechanism in etiology of Graves' disease was observed for the first time in 1956. Twenty years later cellular auto-immune dysfunction was also described. To day, there is evidence for suppressor T cell deficiency and decrease in T suppressor lymphocytes in Graves' disease and cell mediated immunity might be one of the most important point in the pathogenesis of Graves disease. For the future, cellular auto-immune dysfunction might be used to predict the evolution of the disease and to choice the best therapeutic scheme.

Antithyroid Agents↗
PubMed1987

[T lymphocyte subsets in alveolar lavage and peripheral blood in sarcoidosis and extrinsic allergic alveolitis].

Accumulation of inflammatory and immune cells within lung parenchyma would constitute the initial step in producing the alveolar structural abnormalities. It is usually assumed that alveolitis, as assessed by broncho-alveolar lavage (BAL), represents a biological assessment of lung disease activity. The aim of this study, using monoclonal antibodies, is to characterize the T lymphocytes alveolitis in the lung and in peripheral blood in 3 well-defined populations: 1 degree) control subjects (n = 7); 2 degrees) patients with biopsy proven mediastino-pulmonary sarcoidosis (sarc) (n = 73), classified according to their clinical activity as active, inactive, chronic, and treated; 3 degrees) patients with extrinsic alveolar alveolitis (EAA) (n = 19). For the same BAL volume, the % of CD4+ cells and the CD4/CD8 ratio are increased in chronic and active sarc, contrasting with an increase in the % of CD8+ cells and a decrease in the CD4/CD8 ratio in the EAA. In absolute values, there are 2 times as many CD4+ cells and 5 times as many CD8+ cells in EAA than in sarcoidosis. In sarcoidosis, corticotherapy tends to normalize the CD4/CD8 ratio although the intensity of the lymphocytic alveolitis is not affected. In the peripheral blood, lymphopenia is observed only in the active form of sarc. in the CD4+ population, without any significant change in the CD4/CD8 ratio compared to the other groups. The number and distributions of BAL. T lymphocytes subsets may constitute a biological indicator for diagnostic orientation, but they do not distinguish sufficiently between the different groups of sarcoidosis to be of any prognostic value.

Adult↗
PubMed1987

[Immunologic characteristics of repeated spontaneous abortions].

In 28 couples with spontaneous abortions, data of immunological investigations revealed an elevated frequency of HLA DR compatibility and immunological characteristics defining distinct patterns of immune responsiveness. In the half of women with recurrent spontaneous abortion (RSA) we observed a failure to develop a recognition response to paternal inherited fetal antigens expressed by the lack of classical evidence of in vivo allo-immunization such as antipaternal antibodies, and the absence of the inhibitors of cell-mediated immunity found in maternal blood during pregnancy. In few cases, the paternal cells are inefficient to elicit in vitro maternal cell-mediated lympholysis. In most women with a normal pregnancy occurring after spontaneous abortions or prior to RSA, an immune recognition response was evidenced by the presence of antipaternal antibodies and/or blocking factor acting on in vitro cell-mediated lympholysis. These observations support the hypothesis that immunological process could be the cause of some fetal losses of unknown etiology, through a defective or unsuitable maternal immune response.

Abortion, Habitual↗
PubMed1987

[Anti-CD3 monoclonal antibodies. Characterization and function].

Four anti-T lymphocyte monoclonal antibodies were produced by the hybridoma technique. Percentages of miscellaneous labelled cell suspensions, as profiles of fluorescent histograms, showed a reactivity of these 4 reagents quite comparable to that observed with anti-CD3 monoclonal antibodies. Labelling summation studies, cell-sorting studies and blocking experiments gave similar results as gave other anti-CD3 reagents. Biochemical study and functional tests: modulation effects and mitogenic properties, argued for the belonging of these 4 antibodies to the CD3 cluster. The actual data concerning the CD3 molecule are briefly resumed to underline the interest of such antibodies in the understanding of T-lymphocyte activation mechanisms during the immune response.

Animals↗
PubMed1987

[Value of computer processing of data acquired by cytofluorometry for biological analyses].

The amount of informations relative to cell analysis generated on a flow cytometer must often be processed on a computer so that accurate and efficient analysis can be performed on the stored data, and have the power to consider complex signal distributions. A Ortho 50H flow cytometer was complemented with a Persona 1600 microcomputer (LogAbax) via an acquisition system directly connected to the photomultiplier assemblies. In the configuration we used, three primary signals are processed and stored simultaneously, thus providing six parameters for each cell. The analysis of the data can be delayed or operated immediately after each acquisition. Turbo Pascal was used for all programming. The implanted programs are available for the processing of histograms relative to immunofluorescence or DNA analyses. They allow the user to operate on data obtained after selecting the cells on a two-parameter basis. Examples of immunofluorescence and DNA analyses obtained on experimental preparations are presented.

Animals↗