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J Bariety

Publications and source records attributed to J Bariety.

At least 55 records · Page 3Linked to original sources
PubMed1989

Immunohistochemical study of complement S protein (Vitronectin) in normal and diseased human kidneys: relationship to neoantigens of the C5b-9 terminal complex.

The localization of S protein (Vitronectin) antigen was studied by indirect immunofluorescence and immunoelectron microscopy in normal adult human kidneys and in biopsy specimens from patients with a wide range of renal diseases, and compared with that of neoantigens of the C5b-9 terminal complement complex. S protein antigen was diffusely present in arteriolar perimyocytic matrices, the glomerular basement membrane and mesangial matrix, and tubular basement membranes in the cortex of normal and diseased kidneys without superimposable staining for C5b-9 neoantigens. Cell remnants embedded in normal and sclerotic extracellular matrices expressed S protein antigen and also stained for C5b-9 neoantigens. Several lines of evidence suggested that S protein present in connective matrices most likely represents S protein or C5b-9 complexes trapped from the circulation. Glomerular immune deposits and arteriolar hyalin deposits which contained C5b-9 neoantigens also contained S protein antigen in the same location. In a few specimens from patients with membranous nephritis stage I and IgA nephropathy, immune deposits contained neither detectable C5b-9 neoantigens nor S protein. The observed strong co-staining of immune deposits for S-protein and C5b-9 caution against the generalization that C5b-9 within glomerular immune deposits represent membrane-bound cytolytic complement complexes.

Adult↗
PubMed1989

Human liver Kupffer cells express CR1, CR3, and CR4 complement receptor antigens. An immunohistochemical study.

The expression of complement receptor antigens by human Kupffer cells (KC) was investigated by immunohistochemical techniques in seven normal human liver biopsies. Polyclonal and monoclonal antibodies were revealed by double labeling of cells using indirect immunofluorescence and immunoenzymatic techniques or by using double immunoenzymatic techniques. In most experiments, one antigen was revealed by streptavidin-biotin-peroxidase complexes whose reaction product was examined by light microscopy and the second antigen stained using the alkaline phosphatase antialkaline phosphatase method visualized by fluorescence microscopy using fluorescein isothiocyanate or tetramethylrhodamine isothiocyanate filters. KC were identified using monoclonal antibody EBM11 that recognizes 100% of KC in hepatic lobules and was paired with each antibody directed against complement receptors. CR1 and CR3 (alpha- and beta-chains) were found to be the predominant receptor antigens expressed by human KC. CR4 (p150,95) was expressed on all KC, but staining with anti-CR4 monoclonal antibodies was consistently weaker than that observed with anti-CR3 antibodies. No staining of KC was observed with anti-CR2 (CD 21) antibodies. Expression of CR1, CR3, and CR4 complement receptors on KC provides the cells with an optimal capacity to bind and phagocytize particles or immune complexes coated with any type of ligands for C3 receptors.

Antibodies, Monoclonal↗
PubMed1989

The human C3b receptor (CR1).

The human complement system is comprised of 19 plasma components and regulatory proteins and of at least 9 distinct cellular receptors for these proteins or their activation fragments. The important role of complement in host defense against infection is related to its capacity to opsonize microorganisms, lyze target cells, and induce the release of inflammatory mediators from leukocytes. Complement participates in the processing and clearance of immune complexes and in regulation of the immune response. Most of the biologic effects derived from complement activation depend on ligand-receptor interactions between complement proteins or their cleavage fragments and specific receptors on cells. Two types of ligands are generated during complement activation: soluble low-molecular-weight ligands, such as the anaphylatoxins C3a and C5a, and so-called bifunctional ligands that attach both to the target of complement activation (opsonins) and to the appropriate receptor on effector cells. The most abundant complement protein in plasma is C3. Activation of the classic and alternative complement pathways generates C3 convertases that cleave C3 into an anaphylatoxic fragment, C3a, and a major fragment, C3b, which is capable of forming a covalent linkage with the targets of complement activation. Surface-bound C3b is the preferential ligand for the C3b receptor, CR1 (CD 35), which is expressed on most peripheral blood cells. The receptor plays an important role in the processing of immune complexes, the phagocytosis of C3b-bearing microorganisms, and regulation of the immune response. The cellular expression of the molecule is decreased in patients with systemic lupus erythematosus (SLE) and in patients infected with the human immunodeficiency virus (HIV).

Antigen-Antibody Complex↗
PubMed1988

Peritubular cells are the site of erythropoietin synthesis in the murine hypoxic kidney.

Erythropoietin (Epo)-producing cells were identified in the murine hypoxic kidney by in situ hybridization. Profound anemia was induced in order to greatly increase Epo production. This resulted in high levels of Epo mRNA in the kidney. 35S-labeled DNA fragments of the murine Epo gene were used as probes for in situ hybridization. Control experiments conducted in parallel included kidneys of nonanemic mice, RNase-treated hypoxic kidney sections, and 35S-labeled non-Epo-related DNA. The Epo probe gave a specific hybridization signal in the hypoxic kidney in the cortex and to a lesser extent in the outer medulla. Glomerular and tubular cells were not labeled. All positive cells were identified as peritubular cells. Using immunofluorescence, we showed that cells with the same topography contained Factor VIII-related antigen. These data demonstrated that peritubular cells, most likely endothelial cells, constitute the major site of Epo production in the murine hypoxic kidney.

Animals↗
PubMed1988

Presence of the C3b complement receptor (CR1) antigen in the glomerular basement membrane of human fetal kidneys.

The distribution pattern of the C3b receptor (CR1) antigen, one of the earliest differentiation markers of the podocyte plasma membrane, has been studied during human renal ontogenesis by indirect immunofluorescence and immunoelectronmicroscopy using Fab'2 fragments of anti-CR1 antibodies. CR1 antigen has been detected at the open-stage glomerulus, which precedes constriction of the vascular pole, along the capillary wall, in a thick and homogeneous pattern of staining. By immunoelectronmicroscopy, CR1 antigen was present on the porocyte plasma membrane towards the glomerular basement membrane (GBM), and diffusely distributed within the GBM according to a decreasing intensity gradient from podocytes to endothelial cells. At a later stage of differentiation ('closed' glomerulus stage) when constriction of the vascular pole has occurred, the podocyte plasma membrane appeared diffusely labelled for CR1; the GBM was also stained with a decreasing intensity gradient from podocytes to endothelial cells. This result indicates that a plasma membrane receptor belonging to the cell coat of podocytes can be found in the extracellular space within the GBM. Thus the antigenic repertoire of the GBM of human fetal kidney comprises antigens of constituent molecules of the extracellular matrix and planted antigens originating from adjacent cells.

Basement Membrane↗
PubMed1988

Distinct phenotypic composition of diffuse interstitial and perivascular focal infiltrates in renal allografts: a morphometric analysis of cellular infiltration under conventional immunosuppressive therapy and under cyclosporine A.

Phenotypic analysis of interstitial mononuclear cell infiltrates was undertaken in 40 transplant renal specimens obtained from 38 patients in order to assess the influence of immunosuppressive therapy. Thirteen patients were given conventional immunosuppressive treatment (azathioprine and prednisone) and the other 25 received cyclosporine. The immunostaining was performed using seven antileucocyte antibodies by alkaline phosphatase-anti-alkaline phosphatase method. Interstitial infiltrates were distributed in two patterns: diffuse infiltrates and periglomerular/perivascular aggregates. The phenotypic composition was distinct in these two patterns: in diffuse infiltrates, monocytes/macrophages (EBM 11) represented the predominant inflammatory cell and were associated with a minor component of T cells (T 11). In contrast, aggregates had a major T lymphocyte phenotype in addition with few foci of B cells. T4 subset of T lymphocytes always predominated over T8 subset. The repartition and the proportion of each cell type were not significantly different in rejecting and not rejecting grafts and were not affected by the immunosuppressive regimen.

Administration, Oral↗
PubMed1988

Detection and localization of renin messenger RNA in human pathologic tissues using in situ hybridization.

In order to investigate the synthesis of renin in human pathologic tissues, the authors used in situ hybridization to detect and localize renin messenger RNA (mRNA). The probe was a 35S-radiolabeled 1.1-kb length complementary DNA of human renal renin. To compare the synthesis with the presence and the storage of renin, renin antigen was assessed by immunohistochemistry in the same tissues. The human pathologic tissues were as follows: two ischemic kidneys related to renovascular hypertension; two renal juxtaglomerular cell tumors; one extrarenal renin-secreting epithelioid sarcoma of soft tissues. In ischemic kidneys, the cells containing both renin mRNA and renin protein were found in numerous juxtaglomerular apparatus and in the wall of arterioles, shown by combined in situ hybridization and immunohistochemistry. Most of the tumor cells in the juxtaglomerular cell tumors and scarce tumor cells in the epithelioid sarcoma of soft tissues were positive by in situ hybridization and immunohistochemistry. These findings demonstrate that the presence of renin in these tissues is associated with local cellular production of renin. In particular, smooth muscle cells of the wall of arterioles are definitely capable of synthesizing renin. Moreover, in these tissues, gene expression (renin synthesis) and renin storage are concordant.

Adult↗
PubMed1987

Glomerular extracellular roughly granular material (ERGM). Its autofluorescent property and the question of its nuclear origin.

A glomerular extra-cellular roughly granular material (ERGM) has been described by several authors, mainly in association with membranoproliferative glomerulonephritis. This material is clearly identified on light and electron microscopy. Another peculiar morphological character of ERGM is its property of autofluorescence detailed in this study. The precise nature of this granular material remains questionable. Immunostaining shows the lack of superposition of autofluorescent ERGM with C3 and with C5b9. Nuclear origin of ERGM suspected on ultrastructural features failed to be proven by using immunolabelling with an anti-DNA serum.

Cell Nucleus↗
PubMed1987

Down modulation of Heymann's nephritis by mercuric chloride.

The time course of Heymann's nephritis (HN), assessed on proteinuria and immunomorphology, has been compared in Lewis (LEW) rats immunized with BB alone (group A) or injected with HgCl2 and subsequently immunized in a similar manner (group B). Whereas all rats from group A developed typical HN characterized by heavy proteinuria and abundant glomerular immune deposits, rats from group B did not develop or developed a markedly attenuated form of HN; proteinuria was never detectable, immune deposits were absent or minimal. No abnormalities were found in rats injected with HgCl2 alone. In order to explain our findings, we have studied the glomerular and tubular expression of the 330 kD nephritogenic glycoprotein (gp330) as well as the corresponding antibody response. In rats receiving HgCl2, gp330 was normally expressed on BB and glomerular epithelial cells as indicated by in vitro and in vivo binding of anti-gp330 antibodies, but titers of anti-BB and anti-gp330 antibodies were considerably lower than in group A control rats. These findings therefore suggest that HgCl2 acts by its immunodepressive effect recently related to an increase in T suppressor cells. This effect is paradoxical since HgCl2 induces autoimmunity in Brown-Norway rats, and we suggest that it may be akin to observations reported in clinical practice where drugs may be immunostimulatory in some patients and immunodepressive in others. The mercury model may therefore represent a unique tool to evaluate the relationship between genetics and drug-induced immune dysregulation.

Animals↗
PubMed1987

Is thromboxane a potent antinatriuretic factor and is it involved in the development of acute renal failure?

Glycerol-treated rats exhibited significantly increased urinary thromboxane B2(TXB)2, prostaglandin E2 (PGE2) and 6-ketoprostaglandin F1 alpha (6kPGF1 alpha) excretion and urine volume (UV). These increases were associated with significant decreases in creatinine clearance (CCr), urinary sodium concentration (UNa), urinary sodium excretion (UNaV), and fractional excretion of sodium (FENa%), which is consistent with the development of the prerenal (reversible) phase of acute renal failure (ARF). When glycerol-treated rats were pretreated with a selective inhibitor of thromboxane A2 (TXA2) synthesis (imidazole), urinary PGE2 and 6kPGF1 alpha excretion and UV remained unchanged, whereas CCr, UNa, UNaV decreases were partially prevented. Additionally, FENa% was increased, indicating inhibition of sodium reabsorption. The findings indicate that inhibition of TXA2 synthesis increases UNaV and partially improves CCr in glycerol-treated rats. Further histologic observation and functional follow-up over longer periods of time are needed to clarify the role of TXA2 in the development of ARF.

Acute Kidney Injury↗
PubMed1987

Freeze-fracture cytochemistry of rat glomerular capillary tuft. Determination of wheat germ agglutinin binding sites and localization of anionic charges.

We propose here the use of freeze-fracture to gain access and to label in vitro glomerular components and locate WGA receptors and anionic sites. Tissues are frozen, fractured under liquid nitrogen, and thawed. Freeze-fracture rendered all glomerular structures directly accessible to the reagents. This made possible study of the nature and topology of cationized ferritin and WGA binding sites. WGA-gold complexes were observed over plasma membranes of podocytes and of endothelial and mesangial cells. Labeling of podocytes and endothelial cells was similar in the mesangial area and in the peripheral part of the capillary loop. Cross-fractures of extracellular matrices showed that WGA bound uniformly to the glomerular basement membrane (GBM) as well as to mesangial matrix. In fractured specimens treated with neuraminidase, WGA was no longer observed over podocytes but it consistently labeled the surface of endothelial and mesangial cells. Whereas in GBM cross-sections WGA binding was greatly reduced or even abolished, it remained unmodified in the mesangium. This shows that only NeuNAc (sialic acid) might account for the binding of WGA to podocytes, whereas GlcNAcs appear to be the main WGA binding sites on endothelial and mesangial cells and in the mesangial matrix. Both NeuNAc and GLcNAc residues are probably associated in GBM. With cationized ferritin (pI 8.3) at pH 7.4, intense, continuous labeling was seen all over the different plasma membranes, denser in podocytes than in endothelial cells. CF was also observed in cross-fractured profiles of extracellular matrices and never appeared agglutinated in discrete sites.

Animals↗
PubMed1987

Effect of methylprednisolone and cyclophosphamide in mercury-induced autoimmune glomerulonephritis.

The effects of methylprednisolone and of cyclophosphamide were tested in mercury-induced autoimmune disease in Brown-Norway rats. Survival, proteinuria, presence of antiglomerular basement membrane bound antibodies and of immune complex type deposits, amounts of circulating immune complexes, and total serum IgE were studied. Serum IgE represents the most sensitive marker in this drug-induced autoimmune disease. Methylprednisolone alone (1.5 mg/kg per day) affected the course of the disease only slightly. Cyclophosphamide (20 mg/kg every other day) given from day 0 completely prevented all the autoimmune manifestations, but the rats were profoundly immunosuppressed. The same protective effect was obtained with lower cyclophosphamide dosage (15 mg/kg on day 0 and then 2 mg/kg per day). More interestingly, cyclophosphamide given from day 10 or 15 (20 mg/kg twice a week or every other day), at a time when the disease was already expressed, resulted in partial or complete recovery, provided that the rats had not exhibited heavy proteinuria before initiation of treatment. Cyclophosphamide is therefore a powerful agent, able to prevent and even to reduce the consequences of polyclonal activation in this model.

Animals↗
PubMed1987

Glomerulonephritis, B monoclonal small lymphocytic lymphoma and mixed cryoglobulinemia.

A novel association in the same patient with small lymphocytic lymphoma, type II cryoglobulinemia and glomerulonephritis is reported. This case is also characterized by a quite unusual sequence of glomerular alterations. A first renal biopsy showed severe endocapillary proliferative glomerulonephritis due to monocytic infiltration without any evidence of deposition of immune reactants. The immune deposits associated with type II cryoglobulinemia were only observed at a second renal biopsy performed five months later. This case shows that mononuclear cells can be responsible in and of themselves for severe glomerular damage, without deposition of immune material, and suggests that monocytic infiltration might be the first stage of type II cryoglobulinemia associated glomerulonephritis.

B-Lymphocytes↗
PubMed1986

Angiotensin I converting enzyme in human intestine and kidney. Ultrastructural immunohistochemical localization.

The localization of immunoreactive angiotensin I-converting enzyme (ACE) has been investigated at the optical and ultrastructural level with anti-human ACE antibodies in the human kidney and small intestine. In both tissues ACE was found in blood vessels and in extravascular situation in the absorptive epithelial cells of intestinal mucosa and renal proximal tubules. Ultrastructural immunohistochemistry showed that in intestinal and renal proximal tubular cells ACE was prominent in microvilli and brush borders. In the kidney ACE was also present on the basolateral part of the plasmalemmal membrane, where it may contribute to the regulation of angiotensin II-dependent absorption processes. Intracellular positivities were also observed inside the renal vascular endothelial and proximal tubular cell in endoplasmic reticulum and nuclear envelope reflecting the synthesis and the cellular processing of ACE. The intestinal microvascular endothelium was strongly labeled suggesting that the mesenteric circulation is an important site for the production of angiotensin II. Vascular endothelial ACE was also detected in the peritubular but not glomerular capillaries of the kidney.

Antibodies↗