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Biomedical subjects

M C Bene

Publications and source records attributed to M C Bene.

At least 91 records · Page 5Linked to original sources
PubMed1984

IgA nephropathy: dimeric IgA-secreting cells are present in episcleral infiltrate.

Recent publications have reported a frequent association between IgA nephropathy and episcleritis. In this article, the authors report on the immunohistologic study of an episcleral biopsy obtained in a female patient with Berger's disease and frequent episodes of episcleritis. Numerous dimeric-IgA-secreting cells were demonstrated in the episcleral inflammatory infiltrate. It also should be mentioned that microhematuria often occurred within a few days after the beginning of episcleritis in this patient. These results suggest the participation of ocular mucosal immunity in some cases of IgA nephropathy.

Adult↗
PubMed1984

Behaviour of thyroid tissue from patients with Graves' disease in nude mice.

Thyroid tissue from five patients with hyperthyroidism due to Graves' disease was transplanted into nu/nu mice (2 to 4 mice per thyroid) in order to assess whether the tissues would remain hyperfunctional. Before surgery, the patients received only propranolol and iodine for ten days. Transplants were removed from the mice after 10, 20, 30 or 57 days, and compared to the initial tissue, as well as toxic nodules from two patients and thyroid tissue from two normal subjects grafted similarly. All transplants survived, as proven by histology and autohistoradiography with 131I uptake, while all signs of hyperfunction and dysimmunity disappeared. Conversely, both transplanted toxic nodules remained hyperfunctional. These results indicate that, in spite of the in situ presence of most factors of auto-immune reactions, thyroid tissue from patients with Graves' disease is not autonomous and depends on the extra-thyroid environment.

Adult↗
PubMed1984

Transplantation of human hyperthyroid tissue to the nude mouse. An experimental model.

This study analyzes the outcome of human normal and hyperfunctioning thyroid tissue transplanted to the nude mouse. Thyroid fragments from 7 patients with Graves' disease were transplanted to nude mice (nu/nu). Before surgery, the patients had been treated with propranolol and iodine; none had received antithyroid therapy. The transplants were removed on the 12th day following transplantation and were studied by light microscopy and autohistoradiography. At this time, all immunologic disorders found on the operative samples had disappeared, and the tissue had lost its hyperfunctioning characteristics. In contrast, transplants from toxic adenoma remained hyperfunctioning, with elevated serum T3 and T4 levels. Similarly, transplants from normal thyroid tissue remained unchanged, and serum T3 and T4 levels remained within the normal range, as if under the influence of the hypothalamic and pituitary regulation of the mice. These findings emphasize the role of the extrathyroid immunologic environment in the regulation of Graves' disease, whereas toxic adenoma remains autonomous.

Adenoma↗
PubMed1983

Immunoglobulin A nephropathy. Quantitative immunohistomorphometry of the tonsillar plasma cells evidences an inversion of the immunoglobulin A versus immunoglobulin G secreting cell balance.

Primary IgA nephropathy (Berger's disease) is characterized by renal deposits of IgA, the origin of which is still unknown. However, several clinical and biological findings suggest that these immunoglobulins might have a mucosal origin, and that such patients should present mucosal abnormalities. This paper reports the results of the immunohistomorphometrical analysis of tonsillar plasma cells from seven patients suffering from Berger's disease and seven controls also with recurrent tonsillitis. IgG, IgA, and IgM-secreting cells were enumerated after immunofluorescent staining of serial frozen-cut sections from 20 tonsils. In controls, a predominance of the IgG-secreting population, similar to this reported in the literature was observed (65% of IgG secreting cells and 29% of IgA plasma cells), while an inversion in the patients' plasma cells percentages was evidenced (IgG:37%, IgA:56%). This increment in the IgA population was paralleled by an augmentation of the number of dimeric IgA-secreting cells (75% of IgA plasma cells), stained both for cytoplasmic IgA and J chain. In controls, the latter cells were in similar proportions as previously reported by others (45% of IgA plasma cells). These results demonstrate an imbalance in the IgA-producing system of patients with Berger's disease, which is in keeping with the hypothesis favoring a mucosal origin for the mesangial IgA present in their kidneys.

Adolescent↗
PubMed1983

[Antigenic markers of immunocompetent cells in rheumatoid synovial membrane].

Immunologic characteristics of cells present in rheumatoid synovium from 15 patients were analyzed either "in situ" on frozen sections or after elution. Monoclonal antibodies directed against T cell subpopulation antigens and anti-Ia-like were used. T cells bearing the phenotype T3+, T4+, Ia+ are numerous, and they appeared gathered in lymphoid follicles and in perivascular areas. They are in close relationship with large Ia+ cells probably macrophagic in nature. Numerous dendritic cells as well as intimal cells are also Ia+. Some ratios T8+/T4+ cells are higher than results previously reported. This discrepancy could be related to drugs received by the patients before surgery.

Anti-Inflammatory Agents↗
PubMed1983

Graves' disease: in situ localization of lymphoid T cell subpopulations.

An in situ analysis of immunological features in thyroids from 15 Graves' disease patients has been performed. This study included a search for immune complexes visualized near the follicle's basement membranes with fluorescent rabbit antisera to human IgG, IgA, IgM, C1q, C3 and C9. Cellular immunity was investigated on the humoral side by visualization of B cells and plasma cells. Two series of monoclonal antibodies (OKT3, 4 and 8, Leu 1, 2a and 3a) were used to label the infiltrating cells' membrane. These studies demonstrated the prevalence of T cells, a majority of them with OKT8/Leu 2a suppressor/cytotoxic phenotype. No correlation was found between this observation and peripheral blood T cell subsets analysis.

Antibodies, Monoclonal↗
PubMed1983

[A new etiology of episcleritis: nephropathies with IgA and/or isolated C3 deposits].

Scleritis is a condition of the eye often associated with systemic diseases, allergy and infections. Nomoto et al. have reported the frequency of episcleritis in patients with IgA nephropathy (Berger's disease), a primary glomerulonephritis initially described by Berger in 1968. It is characterized by mesangial deposits of IgA, and is considered one of the most frequent nephritides in France. We report our study of the association of scleritis with glomerulonephritis (GN). Fifty-three GN patients were examined for the presence of scleritis. The exact type of nephropathy in each patient was determined by a renal biopsy and immunofluorescence studies. Episcleritis was found in 10 GN patients: in 5 out of 27 Berger's disease, 3 out of 4 patients with isolated mesangial C3 deposits, 1 out of 2 patients with membraneous GN, and 1 out of 5 patients with membranoproliferative GN. The finding of episcleritis in 18% of patients with IgA nephropathy is very similar to the results reported by Nomoto et al. (15%). As no other cause of episcleritis was found in these positive patients, the ocular lesion may be considered to be related to their GN. Episcleritis patient had no abnormal levels of serum IgA, but circulating immune complexes activating the alternate pathway of the complement system were present in most of them. In one female patient with Berger's disease and frequent episodes of episcleritis, an episcleral biopsy was obtained for immunohistological studies. Large numbers of dimeric IgA secreting plasma cells were observed in this tissue. These results suggest the involvement of ocular surface immunity in some cases of IgA nephropathy. It might therefore be useful to investigate the renal function of patients presenting recurrent episodes of episcleritis.

Complement C3↗
PubMed1982

Improvement of cellular immunity and IgA production in immunodeficient children after treatment with synthetic serum thymic factor (FTS).

Three children with IgA and IgE deficiency and T-cell defects (two related patients with ataxia telangiectasia and one with common variable immune deficiency) were treated with synthetic serum thymic factor (FTS) intravenously. A reduction in frequency and severity of infection was noted concomitantly with improvement in cell-mediated-immunity tests. Serum IgA, which was absent in two patients, appeared within 4 weeks of treatment and increased significantly in the third patient. Specific antibodies against vaccination antigens appeared for the first time or increased to titres higher than ever before. In two patients, transient interruption of FTS administration was followed by a regression of the immunological improvement, but this disappeared after the treatment was started again.

Adolescent↗
PubMed1982

[T-lymphocyte subpopulations in chronic inflammatory rheumatism].

Monoclonal antibodies to a series of human lymphocytes subpopulations antigens (OKT) specific of the peripheral T cells (OKT3), of the inducer population (OKT4) of the suppressor cytotoxic population (OKT 5, OKT8), and anti-Ia (OKI1) were used to study blood lymphocytes from 50 patients with active or inactive rheumatoid arthritis (RA) and from 23 patients with ankylosing spondylitis (AS). In RA patients, there is a significant decrease of the total T cell population (T3 +) with higher percentages of helper (T4 +) T cells than in controls. In active forms of the disease, there also is a decrease in the suppressor cytotoxic (T5 + and T8 +) subset with a significant increase of the immunoregulating ratios T4 +/T5 + or T4 +/T8 +. Elevated levels of Ia + lymphocytes are found in all RA patients. Corticosteroid treatment seems to erase these abnormalities. On the contrary in AS patients, no significant modification of the T cell populations was evidenced.

Antibodies, Monoclonal↗
PubMed1982

The effects of immunomodulation on peripheral T cell subsets.

Monoclonal antibody assays were employed to monitor modifications induced in human peripheral lymphocyte subsets by thymectomy or the administration of a series of immunomodulating drugs: synthetic thymic factor, cimetidine or various combinations of anti-thymocyte globulin, azathioprine and steroids. In patients with myasthenia gravis, thymectomy produced a gradual progressive decrease in the elevated OKT4/OKT8 ratios associated with this disease until normal ratios were achieved after one year. Administration of synthetic thymic factor to three immunodeficient children for one month produced increased serum IgA levels accompanied by a normalization of proportions of total T cells and T cell subsets. Four of five uremic patients receiving cimetidine exhibited a marked increase in the percentage of OKT8+ T cells observed in subsequent blood samples with a concomitant increase in immature (OKT4+, OKT8+) lymphocytes that suggested an increase in release of such lymphocytes from the thymus. Assessment of 29 longterm renal allograft recipients by repeated T cell monitoring over an extended period of time confirmed the findings of other investigators that an increase in the OKT4+/OKT8+ ratio was predictive of subsequent allograft rejection episodes while subnormal OKT4+/OKT8+ ratios were indicative of possible cytomegalovirus or herpes virus infections.

Animals↗
PubMed1982

IgA nephropathy: characterization of the polymeric nature of mesangial deposits by in vitro binding of free secretory component.

IgA nephropathy, as Berger defined it, is characterized by mesangial deposits of IgA, which are easily visualized by immunofluorescence on kidney biopsies. The structure (mono- or dimeric) of these IgA has not been clearly defined so far. Fifteen renal biopsies were studied to find out whether these IgA are serum monomers, or are polymers from a different origin. This was done by tissue fixation in vitro of free secretory component, which was then visualized by immunofluorescence (IF). In all 15 cases, the IgA deposits were shown to lack bound secretory component, but were able to bind, specifically, with the free secretory component. The presence of J chain in these deposits was also evidenced by indirect IF. These findings favour the hypothesis that these immunoglobulins are polymeric.

Fluorescent Antibody Technique↗
PubMed1982

In vitro induction of monoclonal antibody-defined T-cell markers in lymphocytes from immunodeficient children by synthetic serum thymic factor (FTS).

Lymphocytes from five children suffering from ataxia telangectasia or various unclassified immune deficiencies were tested in vitro for their sensitivity to synthetic serum thymic factor (FTS). The percentages of cells bearing T cell markers were elevated after incubation with FTS at graded concentrations (0.25, 2.5 and 25 ng/ml), by microlymphocytotoxicity or indirect immunofluorescence, using monoclonal anti-Lyt1 antibodies. In four cases, more than 30% of the non-T non-B cells acquired the Lyt1 T cell marker. These four children had low levels of circulating FTS. In the fifth child, who had a normal serum FTS level, and in two age-matched controls, there was no significant increase in the percentage of cells bearing the T marker.

Adolescent↗