14 research outputs found
Reevaluation of the 22-1-1 antibody and its putative antigen, EBAG9/RCAS1, as a tumor marker
BACKGROUND: Tumor-associated antigens are appreciated as diagnostic markers, but they have also prompted tremendous efforts to develop tumor-specific immunotherapy. A previously cloned tumor-associated antigen, EBAG9, was initially defined by reactivity with the monoclonal antibody 22-1-1. Functionally, the EBAG9-encoded gene-product was believed to induce apoptosis in activated immune cells. However, using a cell-biological approach we identified EBAG9 as a Golgi-resident modulator of O-linked glycan expression, the latter product was then recognized by the 22-1-1 antibody. Secondly, EBAG9 expression was found physiologically in all murine tissues examined. This raised the question if EBAG9 is tumor-specific and mediates apoptosis itself or through O-linked glycans generated, among them the cognate 22-1-1 antigen Tn. METHODS: We have used immunohistochemistry to detect the expression of 22-1-1 and EBAG9 in various tissues. Correlation between expression of both antigens in cell lines was analysed by immunoblot and flow cytometry. Apoptosis was studied by using flow cytometry and Caspase-Glo™ 3/7 assay kit. Cellular distribution of EBAG9 was analysed by electron and confocal microscopy. RESULTS: Here, we compared expression of the 22-1-1 and EBAG9-defined antigens in normal and neoplastic tissues in situ. In contrast to 22-1-1 staining, EBAG9 is a ubiquitously expressed antigen in all normal and cancerous tissues. Functional studies on the role of 22-1-1 reactive material did not support any evidence for apoptosis induction. Employing electron and confocal microscopy, a refined subcellular localization of EBAG9 at the Golgi was obtained. CONCLUSION: We suggest that the estrogen-inducible EBAG9 gene-product and the 22-1-1 defined antigen are structurally and functionally separate antigens
Electrospun silk fibroin fiber diameter influences in vitro dermal fibroblast behavior and promotes healing of ex vivo wound models
Protective function of Ahnak1 in vascular healing after wire injury
AIM: Vascular remodeling following injury substantially accounts for restenosis and adverse clinical outcomes. In this study, we investigated the role of the giant scaffold protein Ahnak1 in vascular healing after endothelial denudation of the murine femoral artery. METHODS: The spatiotemporal expression pattern of Ahnak1 and Ahnak2 was examined using specific antibodies and real-time quantitative PCR. Following wire-mediated endothelial injury of Ahnak1-deficient mice and wild-type (WT) littermates, the processes of vascular healing were analyzed. RESULTS: Ahnak1 and Ahnak2 showed a mutually exclusive vascular expression pattern, with Ahnak1 being expressed in the endothelium and Ahnak2 in the medial cells in naive WT arteries. After injury, a marked increase of Ahnak1- and Ahnak2-positive cells at the lesion site became evident. Both proteins showed a strong upregulation in neointimal cells 14 days after injury. Ahnak1-deficient mice showed delayed vascular healing and dramatically impaired re-endothelialization that resulted in prolonged adverse vascular remodeling, when compared to the WT littermates. CONCLUSION: The large scaffold and adaptor proteins Ahnak1 and Ahnak2 exhibit differential expression patterns and functions in naive and injured arteries. Ahnak1 plays a nonredundant protective role in vascular healing
Supportive development of functional tissues for biomedical research using the MINUSHEET(R) perfusion system
Functional tissues generated under in vitro conditions are urgently needed in biomedical research. However, the engineering of tissues is rather difficult, since their development is influenced by numerous parameters. In consequence, a versatile culture system was developed to respond the unmet needs.Optimal adhesion for cells in this system is reached by the selection of individual biomaterials. To protect cells during handling and culture, the biomaterial is mounted onto a MINUSHEET(R) tissue carrier. While adherence of cells takes place in the static environment of a 24 well culture plate, generation of tissues is accomplished in one of several available perfusion culture containers. In the basic version a continuous flow of always fresh culture medium is provided to the developing tissue. In a gradient perfusion culture container epithelia are exposed to different fluids at the luminal and basal sides. Another special container with a transparent lid and base enables microscopic visualization of ongoing tissue development. A further container exhibits a flexible silicone lid to apply force onto the developing tissue thereby mimicking mechanical load that is required for developing connective and muscular tissue. Finally, stem/progenitor cells are kept at the interface of an artificial polyester interstitium within a perfusion culture container offering for example an optimal environment for the spatial development of renal tubules.The system presented here was evaluated by various research groups. As a result a variety of publications including most interesting applications were published. In the present paper these data were reviewed and analyzed. All of the results point out that the cell biological profile of engineered tissues can be strongly improved, when the introduced perfusion culture technique is applied in combination with specific biomaterials supporting primary adhesion of cells
Supplementary Material for: Protective Function of Ahnak1 in Vascular Healing after Wire Injury
<p><b><i>Aim:</i></b> Vascular remodeling following injury substantially
accounts for restenosis and adverse clinical outcomes. In this study,
we investigated the role of the giant scaffold protein Ahnak1 in
vascular healing after endothelial denudation of the murine femoral
artery. <b><i>Methods:</i></b> The spatiotemporal expression pattern of
Ahnak1 and Ahnak2 was examined using specific antibodies and real-time
quantitative PCR. Following wire-mediated endothelial injury of
Ahnak1-deficient mice and wild-type (WT) littermates, the processes of
vascular healing were analyzed. <b><i>Results:</i></b> Ahnak1 and Ahnak2
showed a mutually exclusive vascular expression pattern, with Ahnak1
being expressed in the endothelium and Ahnak2 in the medial cells in
naïve WT arteries. After injury, a marked increase of Ahnak1- and
Ahnak2-positive cells at the lesion site became evident. Both proteins
showed a strong upregulation in neointimal cells 14 days after injury.
Ahnak1-deficient mice showed delayed vascular healing and dramatically
impaired re-endothelialization that resulted in prolonged adverse
vascular remodeling, when compared to the WT littermates. <b><i>Conclusion:</i></b>
The large scaffold and adaptor proteins Ahnak1 and Ahnak2 exhibit
differential expression patterns and functions in naïve and injured
arteries. Ahnak1 plays a nonredundant protective role in vascular
healing.</p