Search results for " Heterologou"
showing 10 items of 103 documents
In Vitro Cultured Islet‐Derived Progenitor Cells of Human Origin Express Human Albumin in Severe Combined Immunodeficiency Mouse Liver In Vivo
2004
Studies in rodents suggest the presence of a hepatopancreatic stem cell in adult pancreas that may give rise to liver cells in vivo. The aim of the present study was to determine the ability of human islet-derived cells to adopt a hepatic phenotype in vivo. Cultured human islet-derived progenitor cells that did not express albumin in vitro were stained with the red fluorescent dye PKH26 and injected into the liver of severe combined immunodeficiency mice. After 3 or 12 weeks, red fluorescent cells were detected in 11 of 15 livers and were mostly single cells that were well integrated into the liver tissue. Human albumin was found in 8 of 11 animals by immunohistochemistry, and human albumin…
High miR-196a levels promote the oncogenic phenotype of colorectal cancer cells.
2009
AIM: To analyze the relevance of the microRNA miR-196a for colorectal oncogenesis. METHODS: The impact of miR-196a on the restriction targets HoxA7, HoxB8, HoxC8 and HoxD8 was analyzed by reverse transcription polymerase chain reaction (RT-PCR) after transient transfection of SW480 cancer cells. The miR-196a transcription profile in colorectal cancer samples, mucosa samples and diverse cancer cell lines was quantified by RT-PCR. Transiently miR-196a-transfected colorectal cancer cells were used for diverse functional assays in vitro and for a xenograft lung metastasis model in vivo. RESULTS: HoxA7, HoxB8, HoxC8 and HoxD8 were restricted by miR-196a in a dose-dependent and gene-specific mann…
Molecular imaging of VEGF in gastrointestinal cancer in vivo using confocal laser endomicroscopy
2010
Vascular endothelial growth factor (VEGF) is a therapeutic target in gastrointestinal cancer (GiC). However, its in vivo visualisation could not be achieved to date with endoscopic techniques. Confocal laser endomicroscopy (CLE) is a novel imaging technique for gastrointestinal endoscopy providing in vivo microscopy at subcellular resolution. The aim of the study was to evaluate CLE for in vivo molecular imaging of VEGF in GiC.Molecular imaging of tumours in APCmin mice, in xenograft models and in surgical specimens of patients with colorectal cancer (CRC) was achieved after application of labelled antibodies. The tumour sites were scanned with the probe for the strongest specific fluoresce…
Xenograft rejection in marine sponges. Isolation and purification of an inhibitory aggregation factor from Geodia cydonium.
1981
In sponges there exists a graft rejection mechanism in which an inhibitory aggregation factor is involved. The inhibitory aggregation factor has been isolated from a culture medium containing dissociated cells of the sponge Geodia cydonium. Using ion-exchange and gel fractionation the factor was purified and shown to be electrophoretically pure. The factor has a molecular weight of 27000 and was characterized as a glycoprotein. The activity of the inhibitory aggregation factor was not affected by heat treatment, but treatment with trichloroacetic acid resulted in the irreversible loss of activity. The inhibitory aggregation factor affects the aggregation-factor-mediated reaggregation of dis…
Magnetic separation of encapsulated islet cells labeled with superparamagnetic iron oxide nano particles.
2012
Islet cell transplantation is a promising option for the restoration of normal glucose homeostasis in patients with type 1 diabetes. Because graft volume is a crucial issue in islet transplantations for patients with diabetes, we evaluated a new method for increasing functional tissue yield in xenogeneic grafts of encapsulated islets. Islets were labeled with three different superparamagnetic iron oxide nano particles (SPIONs; dextran-coated SPION, siloxane-coated SPION, and heparin-coated SPION). Magnetic separation was performed to separate encapsulated islets from the empty capsules, and cell viability and function were tested. Islets labeled with 1000 μg Fe/ml dextran-coated SPIONs expe…
Prolactin supplementation to culture medium improves beta-cell survival
2010
OBJECTIVES.: Recent studies demonstrated that prolactin (PRL) has beneficial effects on β cells for islet transplantation. We examined the effect of human recombinant PRL (rhPRL) supplementation to the culture media to determine its potential use in the context of clinical islet transplantation. MATERIALS AND METHODS.: Each human islet isolated from 14 deceased multiorgan donors was cultured in Miami modified media-1 supplemented with or without rhPRL (500 μg/L) for 48 hr. β-Cell survival and proliferation (BrdU and Ki-67) were determined by laser scanning cytometry. The cytoprotective effects of rhPRL against noxious stimuli were assessed by flow cytometry (tetramethylrhodamine ethyl ester…
Tumour oxygenation during fractionated radiotherapy--comparison with size-matched controls.
1999
The effect of fractionated irradiation on the oxygenation status of experimental tumours was investigated using polarographic assessment of the pO2 distribution. Since an improvement in tumour oxygenation could simply be the result of tumour shrinkage, a comparison of pO2 readings of untreated size-matched control tumours was performed. Irradiation was carried out using 6 fractions of 6 Gy applied within 11 days. A comparison of polarographic pO2 data with size-matched untreated tumours revealed a significant improvement in oxygenation after the irradiation. The median pO2 was 0.9+/-0.1 mm Hg for unirradiated tumours at a volume of 180 mm3, while the corresponding data for irradiated tumour…
Non-specific Effects of Vaccines Illustrated Through the BCG Example: From Observations to Demonstrations
2018
Epidemiological studies regarding many successful vaccines suggest that vaccination may lead to a reduction in child mortality and morbidity worldwide, on a grander scale than is attributable to protection against the specific target diseases of these vaccines. These non-specific effects (NSEs) of the Bacille Calmette-Guérin (BCG) vaccine, for instance, implicate adaptive and innate immune mechanisms, with recent evidence suggesting that trained immunity might be a key instrument at play. Collectively referring to the memory-like characteristics of innate immune cells, trained immunity stems from epigenetic reprogramming that these innate immune cells undergo following exposure to a primary…
Pigmented esthesioneuroblastoma showing dual differentiation following transplantation in nude mice
1989
Esthesioneuroblastoma (ESTH) is a neuroepithelial-cell-derived neoplasm of the olfactory mucosa composed of homogeneous small round cells which contain neurosecretory granules. Melanin has been detected in such tumours only occasionally. Here we describe a new case of ESTH with divergent differentiation. The primary neoplasm was found in a 67 year-old female, involving the left nasal and maxillary sinus; she died of cerebral metastasis ten months after diagnosis. Histologically only small round cells were seen, with S-100 and NSE positivity. Electron microscopy revealed neurosecretory granules and filaments, as well as the occasional presence of melanosomes. A nude mice xenograft line has b…
Engraftment kinetics of human CD34+ cells from cord blood and mobilized peripheral blood co-transplanted into NOD/SCID mice
2004
We have reported short periods of post transplant neutropenia in human patients co-transplanted with cord blood (CB) and low numbers of haploidentical mobilized peripheral blood (MPB) CD34+ cells. To investigate the effect that the proportion of MPB to CB cells may have on engraftment kinetics, we have co-transplanted fixed numbers of human CB CD34+ cells mixed with different numbers of MPB CD34+ cells into NOD/SCID mice. We periodically quantified the proportion of human cells and the relative contribution of MPB and CB cells to the human engraftment on marrow aspirates. At the lowest MPB/CB ratios (5 : 1, 10 : 1), the contribution of CB cells predominated at all time points analyzed, and …