PubMed Health⌕ Search

Biomedical subjects

C Sapin

Publications and source records attributed to C Sapin.

At least 73 records · Page 4Linked to original sources

Induction of susceptibility to HgCl2 immune glomerulonephritis in the Lewis rat by immunocompetent cells from susceptible F1 hybrids.

Susceptibility to HgCl2-induced glomerulonephritis was transferred to resistant Lewis (LEW) rats, irradiated and reconstituted with (LEW X BN)F1 hybrid immunocompetent cells. This glomerulonephritis was similar to that observed in Brown-Norway (BN) rats with a first stage characterized by anti-glomerular basement membrane antibodies and a second stage with immune complex-type deposits in the glomerular tufts and in the small renal arteries.

Animals↗

Ultrastructural study of nephritis induced in Brown Norway rats by mercuric chloride.

Chronic intoxication by mercuric chloride induces a two-phased nephropathy in Brown Norway rats characterized at first by a linear fixation of antiglomerular basement membrane antibody, then by a granular arteriolar and glomerular fixation of IgG superimposed on the linear one. On the 8th and 9th days, concomitant with the glomerular fixation of antiglomerular basement membrane antibodies, electron microscopy studies demonstrated an influx of monocytes into the glomerular and interstitial capillaries and a focal detachment of the glomerular endothelial cells. On the 14th and 15th days, subendothelial heterogeneous material and scattered subepithelial deposits appeared in glomeruli. By the 60th day, no cellular infiltration nor glomerular endothelial alterations persisted. Subepithelial glomerular deposits were seen in half of the animals, and abnormal deposits situated between muscular cells of the arteriolar walls were seen in all of them. These observations suggest that the glomerular fixation of antiglomerular basement membrane antibodies induces transient alterations of the inner aspect of the glomerular capillary wall. Arteriolar and subepithelial glomerular deposits confirm the idea that an immune-complex disease replaces the antiglomerular basement membrane antibody-mediated process. The morphologic expression of the transition between these two mechanisms is evident around the 15th day.

Animals↗

Extrarenal immune complex type deposits induced by mercuric chloride in the Brown Norway rat.

It has been reported previously that HgCl2 chronically injected in the BN rat induced a biphasic renal disease. During the first stage, anti-glomerular basement membrane antibodies appeared and during the second stage, an immune-complex type glomerulonephritis was observed. In the present study, a systemic immune disease is described. During the first stage, antibasement membrane antibodies were observed in various extrarenal structures. Their localization has been found to depend mainly on the characteristics of the endothelium. During the second stage, immune-complex type deposits containing IgG and C3 were found in most vascular structures. Their localization did not apparently depend on the endothelial characteristics. Among the organs tested the lung was most often spared. The occurrence of immune complex deposits was found to depend on the dose of HgCl2 injected: deposits were absent in some high dose HgCl2-injected rats but they were very numerous in low dose HgCl2-injected rats. These deposits probably have a pthogenic role although no major histological lesion could be found. This model may help to explain immune complex type deposits in systemic diseases.

Animals↗

Ultrastructural evidence, by immunoperoxidase technique, for a tubular reabsoprtion of endogenous albumin in normal rat.

The reabsorption of endogenous albumin in the proximal tubules of the normal Munich-Wistar rat has been studied using immunoperoxidase techniques. The lumina of the superficial proximal tubules were found to remain open after in situ fixation, allowing good penetration of the conjugates. Labeling typical of an endocytotic process was observed only in the proximal tubules. This fact suggests that the glomerular filtration barrier is not an absolute one for denogenous albumin.

Albumins↗

Mercuric chloride-induced anti-glomerular basement membrane antibodies in the rat: genetic control.

Mercuric chloride induces anti-glomerular basement membrane antibodies in the Brown-Norway rat. Various other inbred rat strains (Lewis, Wistar AG, August, PVG/c) were not found to be able to produce such antibodies under the same experimental conditions. Hybrids (F1, F2 and F1 x LEW) were bred from Brown-Norway and Lewis rats and injected with mercuric chloride. It has been demonstrated that the induction of anti-glomerular basement membrane antibodies by mercuric chloride in these crosses is under genetic control. The response was found to depend on two or three genes one of which was H-1-linked. The negative results obtained with L.BN congenic rats were in complete agreement with this conclusion.

Animals↗

Induction of anti-glomerular basement membrane antibodies in the Brown-Norway rat by mercuric chloride.

Anti-glomerular basement membrane (GBM) antibodies were induced in the Brown-Norway rat by mercuric chloride. The existence of anti-GBM antibodies was suspected because of the immunofluorescent linear pattern. It was proved because eluted antibodies from kidneys and circulating IgG had an anti-glomerular basement membrane activity. A glomerular basement membrane antigen modified by HgCl2 is probably responsible for the appearance of such antibodies. The previous demonstration of the occurrence of an immun complex type glomerulonephitis, in outbred Wistar rats, under the same experimental conditions, suggests the existence of a genetic control for this type of immune response.

Animals↗

Isolation of rat and rabbit IgM from normal serum using anti-human mu antibody-polyacrylamide beads immunosorbents.

The antigenic relationship between human IgM and IgM from other species has been utilized in isolating rat and rabbit IgM from normal sera by means of an anti-human mu-polyacrylamide beads immunoadsorbent. The isolated IgM was found to be pure by immunoelectrophoretic analysis and Ouchterlony technique. The antisera obtained were monospecific for mu-chains after absorption with IgG. Lastly, the IgM isolated always retained its antibody activity.

Animals↗

Immunoelectron microscopic and immunochemical demonstrations of serum proteins in the alveolar lining material of the rat lung.

By means of antibodies labeled with horseradish peroxidase, autologous albumin and IgG were visualized in electron microscopy on the alveolar epithelial surface of the rat lung, as a continuous cell coat, as free granular deposits, or associated with tubular myelin figures. These 2 proteins were detected by immunochemistry in alveolar washing. After ultracentrifugation of alveolar washing, they were still found in the phospholipid-rich precipitate fraction by immunization of rabbits and by immunoelectron microscopy. Thus, albumin and IgG appeared as normal alveolar components in the rat lung; fibrinogen was not found under normal conditions.

Animals↗

Isolation of normal human IgA, IgM and IgG fragments by polyacrylamide beads immunoadsorbents.

Polyacrylamide beads antibody immunoabsorbents were used in order to isolate human IgA, IgM and fragments of papain-digested human IgG. The proteins obtained were pure as judged by immunochemical techniques. The antisera raised with these purified proteins were monospecific. The binding capacity and the yield were satisfactory. These antibody immunoadsorbents offer several advantages; a) highly purified antigens can be quickly obtained in a one-step procedure from body fluids; b) their handling is easy especially when using a column; c) they can be used for a long period of time and for many experiments without any noticeable loss in their binding capacity.

Absorption↗

Ultrastructural immunoperoxidase demonstration of autologous albumin in the alveolar capillary membrane and in the alveolar lining material in normal rats.

The location of autologous serum albumin within the alveolar-capillary membrane was studied in the rat under physiological conditions using antialbumin antibodies labeled with peroxidase. Albumin was detected in the lung interstitium, and in numerous pinocytic vesicles within endothelial cells and type I alveolar epithelial cells. The immunoreaction was also positive at the level of plasmalemmal membranes of both cell types and in the alveolar lining material.

Animals↗

Inhibition by colchicine of fibrinogen translocation in hepatocytes.

In the rat, 8 h after intraperitoneal administration of colchicine, fibrinogen (detected by antirat fibrinogen antibodies labeled with peroxidase) accumulated in the lumina of the rough endoplasmic reticulum of the hepatocytes; 16 and 24 h after colchicine administration, fibrinogen was detected, respectively, in the lumina of the smooth endoplasmic reticulum and in the Golgi apparatus. The effect of colchicine on the cytoplasmic translocation of fibrinogen could be due to a direct action of the drug on the membranes of the endoplasmic reticulum or could be the indirect result of the disruptive action of the drug on the microtubules.

Animals↗

[The sensitivity of direct and indirect methods in immunofluorescence and immunoperoxidase techniques: a comparative study (author's transl)].

A comparative study of the sensitivities of the immunofluorescence and immunoperoxidase techniques was undertaken. The material used was tissue from experimental and human glomerulonephritis. With the direct method, immunoperoxidase was 10 to 30 times more sensitive than immunofluorescence. However, the sensitivities became equivalent if the level of the labeling in immunofluorescence was equal to or superior to 6. In the indirect method, the sensitivity of the immunoperoxidase technique was one to ten-fold greater than with immunofluorescence.

Animals↗

Glomerulonephritis with - and 1C-globulin deposits induced in rats by mercuric chloride.

Repeated subcutaneous injections of 0.15 or 0.25 mg/100 g of body weight of HgCl(2) may induce a membranous glomerulonephritis in rats. This glomerulonephritis with subepithelial deposits is similar, by electron microscopy and immunohistochemistry, to experimental chronic glomerulonephritis caused by immune complexes and to the human membranous glomerulonephritis.

Animals↗