Search results for "cell separation"
showing 10 items of 122 documents
Three-Dimensional Spheroid Primary Human Hepatocytes in Monoculture and Coculture with Nonparenchymal Cells
2018
Recent advances in the development of various culture platforms are promising for achieving more physiologically relevant in vitro hepatic models using primary human hepatocytes (PHHs). Previous studies have shown the value of PHHs three-dimensional (3D) spheroid models, cultured in low cell number (1330-2000 cells/3D spheroid), to study long-term liver function as well as pharmacological drug effects and toxicity. In this study, we report that only plateable PHHs aggregate and form compact 3D spheroids with a success rate of 79%, and 96% reproducibility. Out of 3D spheroid forming PHH lots, 65% were considered stable (<50% ATP decrease) over the subsequent 14 days of culture, with reproduc…
Primary Mucosal Epithelial Cell Cultivation: A Reliable and Accelerated Isolation
2019
We illustrate a reliable and accelerated isolation routine for mucosal epithelial cells, which thereupon can be used for soft tissue engineering. This is highly important in the field of soft tissue engineering because mucosal equivalents are frequently usable in several surgical fields like gynecology, urology, otorhinolaryngology, ophthalmology, maxillofacial surgery, and many others. In this context the isolation of mucosal epithelial cells suitable for tissue engineering is mandatory. The reliable cultivation of mucosal or skin epithelial cells is challenging and there is currently no reproducible method. We demonstrate a solution for this problem by developing an accelerated and nevert…
A Good Breath of Oxygen for Beta-Like Cells Obtained From Porcine Exocrine Pancreatic Tissue
2011
Ischemia is the most important factor that affects organ survival during harvesting. The two-layer method (TLM) is one of several cold storage solutions that seeks to preserve organs and cells avoiding in vivo and in vitro ischemia. We compared the retrieval of beta-like elements from exocrine pancreatic cells using TLM versus University of Wisconsin (UW) solutions. For this purpose pancreata laparoscopically harvested from 20 female pigs were preserved in UW solution or TLM before digestion. The resulting exocrine cells were divided into 2 groups: the first was cultured in a designed medium to allow differentiation into beta-like cells and the second was cryopreserved before the differenti…
Highly protective in vivo function of cytomegalovirus IE1 epitope-specific memory CD8 T cells purified by T-cell receptor-based cell sorting.
2005
ABSTRACTReconstitution of antiviral CD8 T cells is essential for controlling cytomegalovirus (CMV) infection after bone marrow transplantation. Accordingly, polyclonal CD8 T cells derived from BALB/c mice infected with murine CMV protect immunocompromised adoptive transfer recipients against CMV disease. The protective population comprises CD8 T cells with T-cell receptors (TCRs) specific for defined and for as-yet-unknown viral epitopes, as well as a majority of nonprotective cells with unrelated specificities. Defined epitopes include IE1/m123 and m164, which are immunodominant in terms of the magnitude of the CD8 T-cell response, and a panel of subordinate epitopes (m04, m18, M45, M83, a…
TH17 cells mediate pulmonary collateral priming
2010
Background Our laboratory has shown that inhalational sensitization to new antigens is facilitated through an ongoing T H 2-polarized inflammation of the lung, a phenomenon we call "collateral priming." Objective We were interested to analyze whether a T H 1-polarized pulmonary inflammation also facilitates priming toward new antigens and which cytokine or cytokines are involved. Methods T H 1-polarized T cells were generated in vitro and transferred into congenic mice. Mice were challenged initially with cognate antigen and an unrelated antigen; consecutively, they received cognate antigen or the secondary antigen. Airway inflammation, antigen-specific IgG2a levels, and airway hyperrespons…
Evaluation of the stromal vascular fraction of adipose tissue as the basis for a stem cell-based tissue-engineered vascular graft
2017
Abstract Objective One of the rate-limiting barriers within the field of vascular tissue engineering is the lengthy fabrication time associated with expanding appropriate cell types in culture. One particularly attractive cell type for this purpose is the adipose-derived mesenchymal stem cell (AD-MSC), which is abundant and easily harvested from liposuction procedures. Even this cell type has its drawbacks, however, including the required culture period for expansion, which could pose risks of cellular transformation or contamination. Eliminating culture entirely would be ideal to avoid these concerns. In this study, we used the raw population of cells obtained after digestion of human lipo…
Curasan PRP kit vs. PCCS PRP system
2002
An important reason to improve methods of isolating platelet-rich plasma (PRP) is the potential use of autologous thrombocyte growth factors. In addition to discontinuous cell separation, two methods for extracting PRP that can be performed directly by the surgeon are now available. This study compared the suitability of these two methods for the preparation of PRP. Whole blood was drawn from 47 healthy donors (18 men, 29 women) aged 20-59 years (mean 29.9, SD 7.7). For each donor, PRP was separated by the PCCS method (PCCS Kit, 3i Implant Innovations, Palm Beach Gardens, FL, USA) and by the Curasan method (analogous to the PRP kit, Curasan, Kleinostheim, Germany). Thrombocyte counts differ…
Quantification of thrombocyte growth factors in platelet concentrates produced by discontinuous cell separation.
2002
Platelet concentrates (PC) are increasingly used to increase bone regeneration in pre-prosthetic surgery. Although it is generally appreciated that certain growth factors (PDGF, TGF, EGF, and ECGF) are present in thrombocyte preparations, relatively little is known about these components in quantitative terms. The study reported here analysed the amounts of growth factors in PC produced under standard conditions from healthy volunteers. All the blood samples (237 in total) were analysed using Quantikine ELISA kits (R and D). The mean +/- SD platelet count in whole blood from these donors was 262,000+/-58,000/microl, while in PC produced by discontinuous cell separation it was 1.419,000+/-33…
Advanced Platelet-Rich Fibrin: A New Concept for Cell-Based Tissue Engineering by Means of Inflammatory Cells
2014
Choukroun's platelet-rich fibrin (PRF) is obtained from blood without adding anticoagulants. In this study, protocols for standard platelet-rich fibrin (S-PRF) (2700 rpm, 12 minutes) and advanced platelet-rich fibrin (A-PRF) (1500 rpm, 14 minutes) were compared to establish by histological cell detection and histomorphometrical measurement of cell distribution the effects of the centrifugal force (speed and time) on the distribution of cells relevant for wound healing and tissue regeneration. Immunohistochemistry for monocytes, T and B -lymphocytes, neutrophilic granulocytes, CD34-positive stem cells, and platelets was performed on clots produced from four different human donors. Platelets …
Functional characterization of hepatocytes for cell transplantation: customized cell preparation for each receptor.
2009
The first indication of hepatocyte transplantation is inborn liver-based metabolic disorders. Among these, urea cycle disorders leading to the impairment to detoxify ammonia and Crigler-Najjar Syndrome type I, a deficiency in the hepatic UDP-glucuronosyltransferase 1A1 present the highest incidence. Metabolically qualified human hepatocytes are required for clinical infusion. We proposed fast and sensitive procedures to determine their suitability for transplantation. For this purpose, viability, attachment efficiency, and metabolic functionality (ureogenic capability, cytochrome P450, and phase II activities) are assayed prior to clinical cell infusion to determine the quality of hepatocyt…