0000000000055735
AUTHOR
Karl-herrmann Meyer Zum Büschenfelde
showing 9 related works from this author
Proteinase-3 mRNA expressed by glomerular epithelial cells correlates with crescent formation in Wegener's granulomatosis
2000
Proteinase-3 mRNA expressed by glomerular epithelial cells correlates with crescent formation in Wegener's granulomatosis. Background Wegener's granulomatosis (WG) is characterized by systemic vasculitis with crescentic glomerulonephritis (CGN) and circulating autoantibodies directed against neutrophil cytoplasmic antigens (ANCA). Proteinase 3 (PR-3), a neutral serine proteinase in neutrophils implicated in the growth control of myeloid cells, has been identified as the target antigen for ANCA in WG. Since the kidneys are frequently involved in WG, we studied the in situ expression of PR-3 by renal parenchymal cells. Methods We assessed the expression of PR-3 in kidney biopsies of 15 patien…
Dexamethasone modulates α2-macroglobulin and apolipoprotein E gene expression in cultured rat liver fat-storing (Ito) cells
1991
Fat-storing (Ito) cells are perisinusoidal liver cells thought to play a central role in vitamin A metabolism and fibrogenesis. Glucocorticoids have been shown to be beneficial in the treatment of certain types of liver diseases by delaying the development of cirrhosis. To study the regulatory effects of dexamethasone on Ito cell gene expression, Ito cells were isolated from normal rat liver and primary cultures were established. The effect of dexamethasone on the synthesis of α2-macroglobulin, apolipoprotein E, fibronectin and actin was examined. Protein synthesis was studied both at the protein level and at the RNA level by means of biosynthetic labeling, immunoprecipitation followed by s…
Selection of hepatitis B virus variants with aminoacid substitutions inside the core antigen during interferon-? therapy
2000
The hepatitis B virus (HBV) core antigen carries many epitopes relevant for B and T cell response that show aminoacid variation during viral infection. In a longitudinal analysis, sequential serum samples of 15 patients that suffered from chronic HBV infection were collected before, during, and after high-dose IFN-α treatment. The HBV preCore/Core (preC/C) sequence of the selected samples in each patient was determined and analysed for sequence variations compared to the pretreatment sample. The positions of HBV core aminoacid substitutions were assigned to immunodominant B, CD4+ and CD8+ cell epitopes. Seventy-five percent of all aminoacid substitutions were found within immunodominant T a…
Synthesis of undulin by rat liver fat-storing cells: Comparison with fibronectin and tenascin
1992
Abstract Fat-storing cells (FSCs) are known to synthesize various components of the hepatic extracellular matrix and thereby play an important role during liver fibrogenesis. The aim of our study was to investigate the synthesis of undulin, a recently described connective tissue protein belonging to the fibronectin—tenascin superfamily of glycoproteins, by fat-storing cells in primary culture. SDS-PAGE analysis of immunoprecipitates from cell layer lysates or media pulse-labeled with radioactive methionine revealed undulin-specific bands A (270 kDa), B1 (190 kDa), and B2 (180 kDa) after reduction. A single undulin-specific transcript was detected at about 7 kb. Undulin synthesized by cell-f…
Mutation specific PCR and direct solid phase sequencing assay for the detection of hepatitis B virus pre-C/C mutants in anti-HBe-positive, chronic he…
1994
Sequence analysis of the HBV DNA from patients with anti-HBe+, chronic hepatitis B revealed that the lack of HBeAg is mostly due to a single GA transition at nucleotide position 1896, resulting in a translational stop codon. A point mutation-specific polymerase chain reaction (msPCR) for the detection of this genetic variant was established. Two serologically defined groups of patients with symptomatic chronic hepatitis B (HBeAg+ n = 14, anti-HBe+ n = 11) were included in this study. Viral DNA from 43 sera (26 eAg+/17 anti-HBe+) was amplified twice, using two different sets of PCR primers. Each set contained the same — strand primer, but the + strand primers differed at their 3′-end, thus b…
Quantitation of HCV-replication using one-step competitive reverse transcription-polymerase chain reaction and a solid phase, colorimetric detection …
1994
A solid phase assay for the colorimetric detection of competitively amplified HCV-cDNA has been established and used to investigate clinical samples from patients with chronic hepatitis. The assay is based on the reduction in the amplification of an hepatitis C virus-related competitor molecule by wild-type hepatitis C virus during polymerase chain reaction. The internal standard contains a lac operator sequence, allowing the amount of amplified competitor to be determined using a lac I-repressor/beta-galactosidase fusion protein. The reduction in the amplification of competitor is dependent upon the concentration of HCV-RNA in the original sample. External hepatitis C virus wild-type stand…
Differential expression of collagen types I, III, and IV by fat-storing (Ito) cells in vitro
1992
It has been observed that Ito cells in vitro undergo phenotypical changes ("activation") similar to those noted in vivo during the development of liver fibrosis. Because conflicting data have been published on the amount and different types of collagens synthesized by Ito cells in vitro, collagen biosynthesis was studied at different "activation" stages on both the protein and RNA levels. Immunoprecipitation of endogenously labeled collagen showed that freshly isolated ("resting") Ito cells synthesize mainly collagen type IV. Collagen type I was hardly detectable in the earlier stage of primary culture, but it clearly increased starting 5 days after isolation. Compared with the basal rates …
HBV viral load within subpopulations of peripheral blood mononuclear cells in HBV infection using limiting dilution PCR.
1999
Abstract Extrahepatic viral load in peripheral blood mononuclear cells (PBMCs) of patients with hepatitis B virus (HBV) is still under debate. In this study, HBV infection rates and viral titers were examined within all PBMC subpopulations using limiting dilution-PCR (LD-PCR). PBMCs of patients with acute or chronic hepatitis B were separated by magnetic beads in monocytes, B-cells, CD4+ T-cells, CD8+ T-cells, and NK cells. Using two-round nested PCR, HBV-DNA sequences were detected in all patients examined within each PBMC subpopulation. The frequencies of HBV-positive cells and viral loads were calculated by Poisson analysis of HBV PCR results from serial dilutions of cells and cell lysat…
Hepatitis B defective virus with rearrangements in the preS gene during chronic HBV infection.
1991
We have found a defective form of HBV2 in a HBsAg- and anti-HBe-positive patient with liver cancer. Viral deletions were identified in the preS coding region using PCR. The presence of deleted HBV forms was observed in serum, PBMC, and liver samples. After sequencing 12 clones were analyzed (subtype adr). In 9 out of 12 clones a 183-bp in-frame deletion was recorded in the preS1 region (2995 to 3177). Three out of 9 clones also yielded rearrangements of the preS2 N-terminal part. Four out of 9 showed numerous point mutations in the preS1 and preS2 sequence. In addition, 3 out of 12 clones, which did not show the 183-bp preS1 deletion were found to have small deletions and insertions in the …