Detection of histidine-rich glycoprotein and fibrinogen with nickel-enzyme conjugates: Purification of rabbit HRG.

Nickel-bound alkaline phosphatase and peroxidase enzymes were used to investigate nickel binding to plasma proteins. Rabbit plasma dilutions to 25,000 were positive by ELISA, while Western blot analysis showed a prominent reaction with histidine-rich glycoprotein (HRG) and lower reaction with fibrinogen (Fgn). To confirm their identities, purified HRG and Fgn were demonstrated to react with the nickel-bound enzymes by Western analysis.

Differential expression of laminin isoforms in diabetic nephropathy and other renal diseases.

Laminin a non-collagenous glycoprotein is a major component of the renal glomerular basement membrane and mesangium. Thus far eleven distinct chains have been described, permutations of which make up 15 laminin isoforms. Laminin molecules interact with cells and other matrix molecules during organ development and differentiation.

Renal cell carcinomas and pancreatic adenocarcinomas produce nidogen in vitro and in vivo.

The production of nidogen by four renal cell carcinoma (RCC) and three pancreatic adenocarcinoma (PAc) cell lines has been studied in cell culture and in xenografted tumours in nude mice. In RCC cells, immunoreactivity for nidogen was seen only after exposure to monensin to induce cytoplasmic accumulation of secretory proteins. In PAc cells, immunoreaction was also detectable in control cells.

Childhood membranous nephropathy, circulating antibodies to the 58-kD TIN antigen, and anti-tubular basement membrane nephritis: an 11-year follow-up.

Childhood membranous nephropathy (MNP) with anti-tubular basement membrane (anti-TBM) nephritis is a rare disorder that may have extrarenal manifestations. This article describes a new case to be added to the 10 previously reported. A renal biopsy specimen from a 1-year-old white boy with nephrotic syndrome, microhematuria, and hypertension showed MNP (granular global IgG, IgA and C3, and segmental IgM and C1q) associated with hypercellularity and granular deposits of IgM and C1q in the mesangium, arteriolar IgA, and linear TBM IgG, IgA, and C3.

Tubulointerstitial nephritis antigen (TIN-ag) is expressed in distinct segments of the developing human nephron.

Tubulointerstitial nephritis antigen (TIN-ag) is a 58 kDa glycoprotein restricted within the kidney to basement membranes underlying the epithelium of Bowman's capsule and proximal and distal tubules. Autoantibody formation against this component has been described in association with primary immune-mediated tubulointerstital nephritis, membranous nephropathy and anti-glomerular basement membrane nephritis. In the present report, the ontogeny of this protein was studied in human fetal kidney tissue by immunohistochemical analysis of immature and developing nephrons using a panel of monoclonal and polyclonal antibodies.

Alterations of corneal extracellular matrix after multiple refractive procedures: a clinical and immunohistochemical study.

Purpose: To describe the clinical course and alterations of the corneal extracellular matrix (ECM) and basement membrane (BM) in a cornea after hexagonal keratotomy, transverse keratotomies, and keratomileusis.

Methods: Frozen sections of this cornea and of 12 normal corneas were studied by immunofluorescence with specific antibodies. The patient history was analyzed to allow a clinical correlation.

Abnormalities of the extracellular matrix in keratoconus corneas.

Purpose: To study alterations of the extracellular matrix (ECM) and basement membrane (BM) components in human keratoconus corneas.

Methods: Fifteen normal and 13 keratoconus corneas were characterized by immunofluorescence with antibodies to 23 ECM and BM components.

Results: Keratoconus staining patterns for posterior nonscarred regions and Descemet's membrane were normal.

Detection of tubulointerstitial nephritis antigen (TIN-ag) in Lewis rat.

Tubulointerstitial nephritis antigen (TIN-ag) is a recently described basement membrane component reactive with autoantibodies in some forms of autoimmune mediated tubulointerstitial nephritis. Immunofluorescence studies using polyclonal and monoclonal antibodies have indicated a restrictive tissue distribution for TIN-ag, with the site of most prominent expression the kidney tubular basement membrane. However, Lewis rat does not demonstrate any immunoreactivity for TIN-ag and does not develop tubuloinsterstitial nephritis after injection of tubular basement membrane material.

Basement membrane abnormalities in human eyes with diabetic retinopathy.

Vascular and parenchymal basement membranes (BMs) are thickened in diabetes, but alterations in individual BM components in diabetic eyes, especially in diabetic retinopathy (DR), are obscure. To identify abnormalities in the distribution of specific constituents, we analyzed cryostat sections of human eyes obtained at autopsy (seven normal, five diabetic without DR, and 13 diabetic with DR) by immunofluorescence with antibodies to 30 BM and extracellular matrix components. In non-DR eyes, no qualitative changes of ocular BM components were seen.

Extracellular matrix alterations in human corneas with bullous keratopathy.

Purpose: To uncover abnormalities of extracellular matrix (ECM) distribution in human corneas with pseudophakic and aphakic bullous keratopathy (PBK/ABK).

Methods: Indirect immunofluorescence with antibodies to 27 ECM components was used on frozen sections of 14 normal and 20 PBK/ABK corneas.

Results: Fibrillar deposits of an antiadhesive glycoprotein tenascin in the anterior and posterior stroma, epithelial basement membrane (BM), bullae and subepithelial fibrosis (SEF) areas, and posterior collagenous layer (PCL) were revealed in disease corneas.

Identification of a cDNA encoding tubulointerstitial nephritis antigen.

Tubulointerstitial nephritis antigen (TIN-ag) is a 58-kDa basement membrane glycoprotein that is recognized by human autoantibodies in certain forms of tubulointerstitial nephritis. To further characterize this macromolecule and isolate cDNAs encoding TIN-ag, amino acid sequences from tryptic peptides were used to design and synthesize primers in order to amplify a probe for screening a rabbit kidney cortex cDNA library. A cDNA encoding TIN-ag was cloned and sequenced.

Human corneal basement membrane heterogeneity: topographical differences in the expression of type IV collagen and laminin isoforms.

Background: The corneal epithelium converges at the peripheral zone (limbus) with the conjunctival epithelium, forming a continuous sheet with phenotypically distinct regions--central, limbal, and conjunctival. The epithelial basement membrane (EBM) is important for corneal functions and cell adhesion, but its regional composition is poorly understood. Current literature is controversial as to the occurrence of type IV collagen in the cornea.

Heterogeneity of renal carcinoma.

Monoclonal antibodies were used to study the expression of three recently characterized basement membrane components and two carbohydrate antigens in 11 renal-cell carcinomas, using immunohistological and biochemical techniques. The expression of several site-specific kidney antigens in renal-cell carcinoma were studied to determine the origin of the carcinoma and if it is possible further classify this type of carcinoma. Tubulointerstitial nephritis antigen (TIN) and two alpha-chains of type IV collagen, alpha 1 (IV) and alpha 3 (IV) were studied.

Tubular basement membrane changes during induction and regression of drug-induced polycystic kidney disease.

Defective cell-extracellular matrix (ECM) biophysiology is considered a factor in the development of polycystic kidney disease (PKD). Altered biosynthesis of various ECM components may result in tubular dysmorphogenesis and uncontrolled tubular cystic expansion. In this study, expression of certain ECM components was investigated in a diphenylthiazole (DPT)-induced rat model of PKD.

Application of electron microscopic immunocytochemistry to the human kidney: distribution of type IV and type VI collagen in normal human kidney.

We used immunogold electron microscopic (IEM) techniques with periodate-lysine-paraformaldehyde-fixed and Lowicryl-embedded or cryopreserved tissues to study the distribution of alpha 1(IV) and alpha 3(IV) chains of Types IV and VI collagen in glomerular basement membrane (GBM) and mesangial matrix of glomeruli in normal human kidneys. Monoclonal antibodies to alpha 1(IV) and alpha 3(IV) collagen chains and Type VI collagen could be detected only with cryoultramicrotomy, whereas polyclonal anti-Type IV collagen antibody was detectable in Lowicryl-embedded tissue. Ultrastructural detail was better preserved in the Lowicryl-embedded tissue.

Glomerular distribution of type IV collagen in diabetes by high resolution quantitative immunochemistry.

We examined type IV collagen distribution and density in human diabetic kidneys by quantitative immunogold electron microscopy. We studied normal kidney transplant donors and "slow-track" and "fast-track" insulin dependent diabetic (IDDM) patients. The "slow-track" patients had IDDM for > or = 20 years and mesangial volume fraction (VvMes/glom) of < or = 0.

Tubulointerstitial nephritis antigen interacts with laminin and type IV collagen and promotes cell adhesion.

Tubulointerstitial nephritis (TIN) antigen has been recently identified as a novel basement membrane macromolecule. It consists of a single chain of 58 kDa and exhibits a restricted distribution. The interaction between TIN antigen and laminin or type IV collagen has been studied using solid-phase binding assays and found to be for both macromolecules specific, saturable, and with an affinity in the low micromolar range.

Immunochemical and biochemical evidence for distinct basement membrane heparan sulfate proteoglycans.

Two antigenically and structurally related heparan sulfate proteoglycans (HSPG), with masses of 200 and 350 kDa, have been isolated and characterized from bovine renal tubular basement membranes (BTBM) using DEAE-Sephacel, octyl-Sepharose CL-4B, and Propac PA-1 chromatography. Heparitinase treatment revealed core proteins of 145 and 125 kDa, with corresponding core proteins after trifluoromethanesulfonic acid treatment of 88 and 82 kDa, from the 200- and 350-kDa HSPGs, respectively. The separated HSPGs produced similar tryptic peptide maps, had similar amino acid compositions, and had similarly sized GAG chains.

Role of a basement membrane glycoprotein in anti-tubular basement membrane nephritis.

Tubulointerstitial nephritis antigen (TIN antigen) is a basement membrane component which is recognized by human autoantibodies in TIN and has been shown to induce TIN in Brown Norway (BN) rats. Detectable by immunofluorescent microscopy, TIN antigen reacts with monoclonal, polyclonal, and human autoantibodies in basement membranes of kidney cortex, small intestine, skin and cornea. Specific sites of TIN antigen within kidney cortex include basement membranes of proximal tubules, distal tubules, Bowman's capsule and peritubular capillaries, with highest concentration in proximal tubular basement membrane (TBM).

Characterization of a non-Goodpasture autoantibody to type IV collagen.

Goodpasture's syndrome is a very severe and aggressive autoimmune kidney disease. The patients' autoantibodies, which are pathogenic, are restricted to the C-terminal region of the alpha 3-chain of type IV collagen. In this paper we characterize an anti-type IV collagen antibody from a patient with a non-progressive form of glomerulonephritis.

The Goodpasture antigen: common epitopes in the globular domains of collagen IV.

To determine the nature of Goodpasture antibody-reactive epitopes on the globular domains of collagen IV [non collagenous (NC) domain], Goodpasture antigen was characterized by immunochemical and immunohistological techniques using affinity-purified (AP) Goodpasture autoantibodies. Affinity purification of Goodpasture autoantibodies toward alpha 1(IV), alpha 2(IV), and alpha 3(IV) NC domains was performed and revealed antigenic cross-reactivity with all alpha(IV) NC domain subunits, which was confirmed by inhibition ELISA. Since by immunofluorescent microscopy all 3 AP Goodpasture antibodies only stained the central portion (lamina densa) of bovine glomerular basement membrane, it appears that there are common epitopes reactive with Goodpasture autoantibodies present on alpha 1(IV) NC, alpha 2(IV) NC, and alpha 3(IV) NC domains.

The structural organization of type IV collagen. Identification of three NC1 populations in the glomerular basement membrane.

Type IV collagen, which has long been assumed to contain two alpha 1(IV) and one alpha 2(IV) chains, also contains alpha 3(IV), alpha 4(IV), and alpha 5(IV) chains. Stoichiometry of collagenous alpha(IV) chains differs among tissues, suggesting the existence of subclasses of type IV collagen, each with a unique chain composition. This study seeks to define, by characterization of subunit compositions of NC1 domain populations, the structural organization of type IV collagen from bovine glomerular basement membrane.

Role of antibodies to tubulointerstitial nephritis antigen in human anti-tubular basement membrane nephritis associated with membranous nephropathy.

We report three patients, from two unrelated families, with anti-tubular basement membrane (TBM) antibody nephritis associated with membranous nephropathy. This rare disorder is characterized by nephrotic syndrome, tubular dysfunction, and progression to renal failure. Direct immunofluorescent studies in these patients revealed linear IgG deposition along the proximal TBM, while circulating antibodies reacting with proximal TBM but not with glomerular basement membrane were identified by indirect immunofluorescence.