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Hannover, Germany

Lemke A.K.,University of Kiel | Sandy J.D.,Rush University Medical Center | Voigt H.,University of Kiel | Dreier R.,University of Munster | And 7 more authors.
Cell and Tissue Research | Year: 2010

Pro-inflammatory cytokines induce meniscal matrix degradation and inhibition of endogenous repair mechanisms, but the pathogenic mechanisms behind this are mostly unknown. Therefore, we investigated details of interleukin-1 (IL-1α)-induced aggrecan turnover in mature meniscal tissue explants. Fibro-cartilagenous disks (3 mm diameter×1 mm thickness) were isolated from the central, weight-bearing region of menisci from 2-year-old cattle. After 3 or 6 days of IL-1α-treatment, GAG loss (DMMB assay), biosynthetic activity ([35SO4]-sulfate and [3H]-proline incorporation), gene expression (quantitative RT-PCR) and the abundance (zymography, Western blot) of matrix-degrading enzymes and specific aggrecan products were determined. Meniscal fibrocartilage had a 4-fold lower GAG content (per wet weight) than adjacent articular cartilage, and expressed MMPs-1, -2, -3 and ADAMTS4 constitutively, whereas ADAMTS5 m-RNA was essentially undetectable. Significant IL-1 effects were a decrease in biosynthetic activity, an increase in GAG release and in the expression/abundance of MMP-2, MMP-3 and ADAMTS4. Fresh tissue contained aggrecan core protein products similar to those previously described for bovine articular cartilage of this age. IL-1 induced the release of aggrecanase-generated CS-substituted products including both high (>250 kDa) and low molecular weight (about 75 kDa) species. TIMP-3 (but not TIMP-1 and -2 or a broad spectrum MMP inhibitor) inhibited IL-1-dependent GAG loss. In addition, IL-1 induced the release of preformed pools of three known G1-bearing products. We conclude that aggrecanases are responsible for IL-1-stimulated GAG release from meniscal explants, and that IL-1 also stimulates release of G1-bearing products, by a process possibly involving hyaluronan fragmentation. © Springer-Verlag 2010. Source

Zhang J.,University of Bonn | Dublin P.,University of Bonn | Griemsmann S.,University of Bonn | Klein A.,A-Life Medical | And 5 more authors.
PLoS ONE | Year: 2013

Herein we demonstrate with PCR, immunodetection and reporter gene approaches that the widely used human Glial Fibrillary Acidic Protein (hGFAP)-Cre transgene exhibits spontaneous germ-line recombination activity in leading to deletion in brain, heart and tail tissue with high frequency. The ectopic activity of hGFAP-Cre requires a rigorous control. We likewise observed that a second widely used nestin-Cre transgene shows germ-line deletion. Here we describe procedures to identify mice with germ-line recombination mediated by the hGFAP-Cre and nestin-Cre transgenes. Such control is essential to avoid pleiotropic effects due to germ-line deletion of loxP-flanked target genes and to maintain the CNS-restricted deletion status in transgenic mouse colonies. Copyright: © 2013 Zhang et al. Source

Krenn V.,Zentrum fur Histologie | Kno P.,Zentrum fur Histologie | Ruther W.,Klinik fur Orthopadie | Jakobs M.,Zentrum fur Histologie | And 5 more authors.
Orthopade | Year: 2010

Background: Meniscal degeneration (MD) is a structural change of fibrous cartilage that is common in orthopaedic diagnostics and relevant for health insurance matters. So far, there has been neither a standardised scoring system nor an immunohistochemical marker for MD. Material and method: In this retrospective trial, the meniscal tissue of 60 patients was assessed immunohistochemically for NITEGE (G1 fragment of the proteoglycan aggrecan) expression. NITEGE expression was correlated with defined grades of MD: little (grade 0/1), medium (grade 2), or severe (grade 3). Results: Detection of extracellular NITEGE deposits in grade 2 or 3 MD had a positive predictive value and specificity of 100%, whereas no deposits were found in grade 0/1 MD. Sensitivity in advanced MD was 55%. Detection of extracellular NITEGE correlated positively with the grade of degeneration, as did patient age and the grade of degeneration. The patient age of those with grade 0/1 MD was significantly lower than for grade 3 (p<0.0001). Conclusion: The thoroughly defined degeneration score (grade 1 - grade 3 MD) is suitable to assess the severity of degeneration. Extracellular NITEGE deposits can be regarded as an immunohistochemical marker for advanced (grades 2 and 3) MD. © 2010 Springer Medizin Verlag. Source

Langer H.F.,University of Tubingen | Von Der Ruhr J.W.,University of Tubingen | Daub K.,University of Tubingen | Schoenberger T.,University of Tubingen | And 17 more authors.
Journal of Molecular Medicine | Year: 2010

Tissue injury is inevitably accompanied by disruption of the endothelium and exposure of the subendothelial matrix. To generate a guidance molecule directing progenitor cells to sites of vascular lesions, we designed a bifunctional protein. The protein consists of the soluble platelet collagen receptor glycoprotein VI and an antibody to CD133 (hereafter called GPVI-CD133). In vitro and in vivo, this construct substantially mediates endothelial progenitor cell (EPC) homing to vascular lesions. Exposure of EPCs to GPVI-CD133 did not impair their capability to differentiate toward mature endothelial cells as verified by the formation of colony-forming units, the upregulation of endothelial markers CD31 and CD146 analyzed by flow cytometry or von Willebrand factor and endoglin assessed by immunofluorescence microscopy, as well as the presence of Weibel-Palade bodies using transmission electron microscopy. In vivo, GPVI-CD133 augments reendothelialization of vascular lesions. Thus, this bifunctional protein could be a potential new therapeutic option for cardiovascular diseases. © 2010 Springer-Verlag. Source

Koch R.,Anatomisches Institute | Hennig-Pauka I.,Klinik fur Kleine Klauentiere | Gasse H.,Anatomisches Institute
Pneumologie | Year: 2010

The histological composition of the Lamina propria in pigs especially in the cranial fold of the glottis gives reason to expect other phoniatric properties than in man. Age-related changes must be considered. © 2010 Georg Thieme Verlag KG Stuttgart New York. Source

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