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Biomedical subjects

T Krieg

Publications and source records attributed to T Krieg.

At least 181 records · Page 10Linked to original sources
PubMed1990

Binding to human jejunum of serum IgA antibody from children with coeliac disease.

Jejunal histology and the presence of serum IgA antibodies (JAB) binding to human jejunum in vitro were studied in 139 children with severe malabsorptive symptoms. Among 33 children with confirmed coeliac disease (ESPGAN criteria), 13 (93%) of 14 sampled before starting on a gluten-free diet had JAB, none of 21 sampled had JAB while on a gluten-free diet of long duration, and 90% of 30 sampled during gluten challenge had JAB. 53 children had severe jejunal villous atrophy (probable coeliac disease): 71% of those younger than 2 years and 94% of those aged 2-18 years had JAB during gluten intake. JAB could not be detected in 53 disease control patients (normal jejunal histology) and in 3 coeliac disease patients with selective IgA deficiency. Simultaneous determination of antigliadin (AGA) and antiendomysium (EMA) levels, and gliadin and tissue absorption studies, showed that JAB and AGA are different, whereas JAB and EMA are probably identical. IgA JAB could be the target-organ-related autoantibodies in coeliac disease.

Adolescent↗
PubMed1990

Immunogenetic associations of scleroderma-related antinuclear antibodies.

Patients selected for the presence of scleroderma-related antibodies (anti-DNA-topoisomerase I [anti-topo I; n = 43], anticentromere antibody [ACA; n = 63], or anti-Pm-Scl [n = 12]) were studied for class I and class II major histocompatibility complex antigens, as well as for Gm and Km allotypes. Anti-topo I was associated with HLA-DR5 (70% of patients versus 30.6% of controls; Pcorr = 0.0018, relative risk [RR] = 5.3). All patients with anti-Pm-Scl were positive for HLA-DR3 (versus 23.5% of controls; Pcorr less than 0.001); 6 of these patients were DR3/4 heterozygous (50% versus 3.5% of controls; Pcorr less than 0.001, RR = 27.3). Patients with ACA were frequently positive for HLA-DR1, DR4, or DRw8, with 73.7% demonstrating at least 1 of these alleles (versus 41.2% of controls; Pcorr = 0.0152, RR = 4.0). This group of ACA-positive patients who had DR1, DR4, and/or DRw8 consisted mainly of a subgroup of patients with rheumatoid arthritis. We conclude that different class II major histocompatibility complex antigens influence the formation of anti-topo I and anti-Pm-Scl. Important clinical differences between these patient groups and the immunogenetic heterogeneity support the notion of different antibody-defined scleroderma subsets.

Antibodies, Antinuclear↗
PubMed1990

Clinical association of autoantibodies to fibrillarin with diffuse scleroderma and disseminated telangiectasia.

Circulating autoantibodies against a variety of nuclear and nucleolar antigens are characteristic serologic findings in systemic scleroderma. Some of these antibodies correlate with clinical subsets of the disease. We describe three patients with systemic scleroderma and high autoantibody titers against U3 ribonucleoprotein-associated fibrillarin, a recently identified 34 kD nucleolar protein. These patients showed a progressive course with multiple organ and diffuse skin involvement with disseminated telangiectasia.

Adult↗
PubMed1990

Influence of eicosanoids on fibroblast chemotaxis and protein synthesis in vitro.

Metabolism of fibroblasts plays a key role in wound healing, fibrosis, rheumatoid arthritis, and similar physiological and pathological processes. The regulatory influence of eicosanoids, an important class of inflammatory mediators, on fibroblast metabolism, in these processes is, to date, unclear. The aim of this study was to investigate the effect of some eicosanoids on chemotaxis and protein synthesis of fibroblasts in vitro. Of twelve eicosanoids tested, only 5(S)-HETE, LTB4, and 12(S)-HETE were active as chemo-attractants for fibroblasts. 5(S)-HETE was the most potent attractant. It exerted its maximal activity at 10(-10) mol/l. 12(S)-HETE and LTB4 caused similar dose dependent fibroblast chemotaxis with a maximum of activity at 10(-7) M and 5 x 10(-8) M, respectively. Hydroxylation of LTB4 on C20 or methylation of the carboxy group of 12(S)-HETE decreased reactivity of the parent compounds only slightly. Eicosanoid induced chemotaxis could be antagonized by 12(S)-HETE but not by the proteinaceous chemoattractants fibronectin, PDGF, or EGF. Receptors for peptide and eicosanoid mediated chemotaxis are thus different. Inhibition of collagen synthesis was observed in the presence of 5(S)-HETE and 12(S)-HETE while total protein synthesis was unaffected by 12(S)-HETE and augmented by 5(S)-HETE. These data suggest that certain eicosanoids specifically regulate fibroblast activities in wound healing and similar events of connective tissue reorganization.

12-Hydroxy-5,8,10,14-eicosatetraenoic Acid↗
PubMed1990

Identification of basement membrane components in eosinophilic globules in a case of Spitz's nevus.

A case of Spitz's nevus with eosinophilic globules was examined using antibodies for several components of the basement membrane. Aggregated tumor cells revealed the same characteristics as normal nevocytic nevi, that is, they were surrounded by laminin and type-IV collagen, whereas type-VII collagen was absent. All of these components of basement membranes, including type-VII collagen, were also found in eosinophilic globules, which were densely stained by these antibodies. It is assumed that these eosinophilic globules are essentially composed of basement membrane components, which are probably synthesized by epidermal and possibly also by melanocytic tumor cells.

Basement Membrane↗
PubMed1990

Tumor necrosis factor alpha induces invasiveness of human skin fibroblasts in vitro.

The chemotactic response of fibroblasts plays an important role during wound healing and fibrosis. Several substances have been found to mediate fibroblast migration in vitro. In the tissue, however, fibroblasts have also the potential to pass through connective tissue barriers following a chemotactic stimulus. Since tumor necrosis factor alpha (TNF alpha) is a cytokine released by mononuclear cells during wound healing, we have been interested in studying its effect on the regulation of fibroblast chemotaxis and invasive migration. TNF alpha did not attract skin fibroblasts nor did it alter their chemotactic response towards other chemoattractants like fibroblast conditioned medium or fibronectin. However, whereas normal skin fibroblasts did not invade a collagen I gel, preincubation of the cells with TNF alpha markedly induced their invasive migration into the gel. This seems to be associated with a specific degradation of type I collagen, because TNF alpha did not promote the invasion of skin fibroblasts through a reconstituted basement membrane (Matrigel).

Adult↗
PubMed1990

Type III collagen aminopropeptide and laminin P1 levels in serum of patients with silicosis-associated and idiopathic systemic scleroderma.

A group of 191 patients with systemic scleroderma and 12 patients with silicosis-associated scleroderma were investigated for connective tissue turnover. The serum levels of type III collagen aminopropeptide (P-III-P), the laminin PI (Lam PI) fragment and the acid lysosomal beta-galactosidase (beta-Gal) were determined by specific radioimmunoassays and spectrofluorometry, respectively. Increased levels of type III collagen aminopropeptide strongly correlated with enhanced activity of beta-galactosidase. Both parameters correlated with the clinical course in idiopathic systemic scleroderma and in silicosis-associated scleroderma. Serum levels of Lam PI were also found to be elevated in both groups, although there was no correlation with the severity of the disease. Autoantibodies directed against the DNA topoisomerase Scl-70 and against centromeric proteins were found in a similar range in patients with idiopathic systemic and silicosis-associated scleroderma. These results suggest that P-III-P, Lam PI and beta-Gal are useful serological markers of fibrotic activity and demonstrate similarities between idiopathic systemic scleroderma and scleroderma associated with silica-dust exposure.

Aged↗
PubMed1990

Invasive migration of epidemic Kaposi's sarcoma cells in vitro.

Kaposi's sarcoma (KS) is a low grade malignant neoplasm which shows invasive growth and often occurs in immunosuppressed patients with the Acquired Immune Deficiency Syndrome (AIDS; epidemic KS). It is also found in elderly men where it is usually limited to the skin (classic KS). The present study investigated the chemotaxis and invasive migration of epidemic KS cells in vitro and compared them to cells grown from classic KS lesions and to fibroblasts. Epidemic KS cells demonstrated invasive migration through reconstituted basement membrane (Matrigel) as well as through interstitial connective tissue (collagen I) in early passages, whereas fibroblasts did not invade either barrier. Epidemic KS cells in late passages did not show any invasive migration. Following pretreatment with tumour necrosis factor alpha (TNF-alpha) there was no enhanced migration through the Matrigel and collagen I for epidemic KS cells, whereas classic KS cells showed an increased migration through the type I collagen barrier.

Basement Membrane↗
PubMed1990

The hemidesmosomal plaque. I. Characterization of a major constituent protein as a differentiation marker for certain forms of epithelia.

To examine whether constituent proteins of hemidesmosomal structures can be used as markers for certain pathways of epithelial differentiation we have examined the occurrence of the major M- approximately 230,000 plaque protein, the "bullous pemphigoid" (BP) antigen. Several bovine, rat and human tissues and bovine cell culture lines were examined, using different human autoantibody preparations in immunocytochemistry and immunoblotting. We report that this protein, also unequivocally identified by cDNA cloning from expression libraries and DNA sequencing, occurs not only in different stratified epithelia but also, apparently always in hemidesmosomal structures, in urothelium of bladder and the complex epithelia of trachea, bronchus and several glands, notably myoepithelium-containing skin glands, the mammary gland and salivary glands. The protein is absent, however, in all single-layered epithelia and in several tissues reported to have subplasmalemmal densities structurally similar to hemidesmosomes, such as Purkinje fibers of heart, meninges and perineuria. A mammary-gland-derived epithelial cell line (BMGE + H) is particularly rich in hemidesmosomes. This has been used to study the endocytotic uptake of hemidesmosome-containing plasma membrane domains into cytoplasmic vesicles upon detachment of cell sheets during treatment with dispase, a proteolytic enzyme. We propose to use the Mr- approximately 230,000 plaque protein as a marker selective for certain subsets of epithelial cell types and epithelium-derived tumors in studies of fetal and tumor development, including differentiation diagnosis of carcinomas.

Amino Acid Sequence↗
PubMed1990

Cyclosporin in localized and systemic scleroderma--a clinical study.

Four patients with systemic scleroderma and 1 patient with localized scleroderma were treated with ciclosporin (CS), given in daily doses between 2.2 and 5.6 mg/kg body weight for 3-26 months. Under this medication clinical improvement was observed in 4 patients with partial regression of cutaneous sclerosis and inflammation, healing of fingertip ulcerations or leg ulcers and improvement of articular mobility. However, in 1 patient with rapidly advancing systemic scleroderma a short-term therapy with CS in low doses (2-3 mg/kg body weight) resulted in arterial hypertension and renal dysfunction. Therefore careful selection of patients and close-meshed controls are indicated when CS is considered as anti-inflammatory treatment in scleroderma.

Acute Kidney Injury↗
PubMed1990

Co-localization of transforming growth factor beta 2 with alpha 1(I) procollagen mRNA in tissue sections of patients with systemic sclerosis.

The role of transforming growth factor beta 2 (TGF-beta 2) in the pathogenesis of systemic sclerosis (SSc) was investigated by in situ hybridization of skin biopsies from six patients with SSc. Two patients with acute systemic lupus erythematosis (SLE), one with acute dermatomyositis (DM), and three healthy individuals were used as controls. TGF-beta 2 mRNA was found to be co-localized with pro alpha 1(I) collagen expression around dermal blood vessels in all patients with the inflammatory stage of SSc, whereas there was no expression of either gene in the dermis of patients in the fibrotic stage, the SLE patients or the normal controls. These findings provide evidence that TGF-beta 2 released by inflammatory cells around blood vessels may play a role in mediating the collagen gene disregulation in fibrosis.

Blood Vessels↗
PubMed1990

Dermatitis herpetiformis bodies. Ultrastructural study on the skin of patients using direct preembedding immunogold labeling.

Skin samples from three adult patients with dermatitis herpetiformis (DH) and granular IgA deposits in the papillary tips were studied using ultrastructural immunogold technique. IgA positive, so-called DH bodies were identified as amorphous clumps--most probably immunocomplex aggregates--scattered throughout the upper papillary dermis. Dermatitis herpetiformis bodies were seen underneath the basement membrane, sometimes along microfibrillar bundles, as well as adjacent to the papillary collagen fibers and within the surface (microfibrillar) region of elastic tissue. Some DH bodies, however, were not related to any fibrillar components. The collagen and elastic fibers, microfibrillar bundles, anchoring fibrils, and elastic microfibrils themselves were unlabeled. Dermatitis herpetiformis bodies were not found in normal human skin. The results of our ultrastructural study indicate that DH bodies either are bound to a nonfibrillar component of dermal connective tissue or represent deposits of immune complexes trapped in DH skin.

Actin Cytoskeleton↗
PubMed1990

Chemotactic migration of normal dermal fibroblasts towards epidermal growth factor and its modulation by platelet-derived growth factor and transforming growth factor-beta.

During the repair phase of wound healing, fibroblasts migrate to the site of injury where they proliferate and synthesize constituents of the extracellular matrix of connective tissue. Their activity is regulated by mediators originating from cells of the blood clotting and inflammatory stage such as platelet-derived growth factor, epidermal growth factor, transforming growth factor-beta and other cytokines. This communication shows that chemotactic migration of normal dermal fibroblasts is elicited by epidermal growth factor in vitro and that platelet-derived growth factor and transforming growth factor-beta can down-regulate this activity. This suggests that in vivo these growth factors are part of an intricate network which connects and coordinates proliferation, protein synthesis and chemotactic migration of fibroblasts.

Cell Movement↗
PubMed1990

[Pulmonary manifestation of progressive systemic scleroderma: prognostic value of centromere antibodies and antibodies to Scl-70 nucleoprotein].

We examined 74 patients with systemic sclerosis. 21 of them (= 28%) had Scl-70 antibodies in their blood serum and 12 (= 16%) were anticentromere antibody positive, whereas in 41 cases (= 56%) none of these antibodies could be detected. In patients with Scl-70 antibodies lung function tests showed a decrease in vital capacity (p less than 0.05), total capacity (p less than 0.01), and diffusing capacity (p greater than 0.05/n.s.) as compared to ACA-positive patients. A limitation of pulmonary function was seen in 76% of Scl-70-positive patients, in 44% of antibody-negative patients, and in only 33% in the ACA-positive group. A disabling respiratory limitation was found in 14% of Scl-70-positive patients, and in 7% of antibody-negative patients, whereas none of the ACA-positive patients had a higher degree of respiratory insufficiency. We conclude that pulmonary involvement in systemic sclerosis is most frequent and severe in patients with Scl-70 antibodies; it is relatively rare and of minor severity in ACA-positive patients. Antibody-negative patients are in between these extremes.

Adolescent↗
PubMed1989

[Changes in collagen connective tissue and fibroblasts in aging].

Some of the characteristic features of aging skin, such as wrinkling, loss of elasticity, and atrophy, can largely be attributed to dermal changes. The amount of collagen in the skin decreases, while the cross linking increases, and the solubility of collagen is reduced. The total number of fibroblasts decreases, and their metabolism shows characteristic alterations. Some of the functions of fibroblasts in aging skin, such as the synthesis of protein and collagen, but also proliferation and chemotaxis, can be investigated by means of in vitro models. In addition, various syndromes of premature aging (e.g. progeria, Werner's syndrome) have proved useful models and have contributed considerably to the understanding of aging processes.

Aged↗
PubMed1989

[Fibrocytes and fibroblasts. Definition and significance in wound healing and fibrotic diseases of the skin].

Fibroblasts are not only responsible for connective tissue synthesis in the dermis, but in addition have to fulfill several functions including chemotaxis, attachment and proliferation as well as tissue remodelling. They interact with various molecules of the extracellular matrix which to a certain extent can regulate some of these cellular functions. Furthermore fibroblast metabolism is influenced by cytokines released by other cells. Some of these factors e.g. TNF, TGF-beta or interferon-y have been shown to regulate specifically some functions whereas others can modulate the cellular differentiation. An exact knowledge of the interaction with the extracellular matrix and the response to various cytokines released during pathological conditions is required for the understanding of altered fibroblast metabolism leading to wound healing defects or fibrosis.

Fibroblasts↗