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31.
Evaluation of trehalose and sucrose as cryoprotectants for hematopoietic stem cells of umbilical cord blood 总被引:1,自引:0,他引:1
Rodrigues JP Paraguassú-Braga FH Carvalho L Abdelhay E Bouzas LF Porto LC 《Cryobiology》2008,56(2):144-151
Bone marrow transplantation (BMT) is a therapeutic procedure that involves transplantation of hematopoietic stem cells (HSC). To date, there are three sources of HSC for clinical use: bone marrow; mobilized peripheral blood; and umbilical cord blood (UCB). Depending on the stem cell source or type of transplantation, these cells are cryopreserved. The most widely used cryoprotectant is dimethylsulfoxide (Me2SO) 10% (v/v), but infusion of Me2SO-cryopreserved cells is frequently associated with serious side effects in patients. In this study, we assessed the use of trehalose and sucrose for cryopreservation of UCB cells in combination with reduced amounts of Me2SO. The post-thawed cells were counted and tested for viability with Trypan blue, the proportion of HSC was determined by flow cytometry, and the proportion of hematopoeitic progenitor cells was measured by a colony-forming unit (CFU) assay. A solution of 30 mmol/L trehalose with 2.5% Me2SO (v/v) or 60 mmol/L sucrose with 5% Me2SO (v/v) produced results similar to those for 10% (v/v) Me2SO in terms of the clonogenic potential of progenitor cells, cell viability, and numbers of CD45+/34+ cells in post-thawed cord blood cryopreserved for a minimum of 2 weeks. Thus, cord blood, as other HSC, can be cryopreserved with 1/4 the standard Me2SO concentration with the addition of disaccharides. The use of Me2SO at low concentrations in the cryopreservation solution may improve the safety of hematopoietic cell transplantation by reducing the side effects on the patient. 相似文献
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Abdelhay A Magnin JP Gondrexon N Baup S Willison J 《Applied microbiology and biotechnology》2008,79(5):881-888
In the present paper, the degradation of phenanthrene, a model polycyclic aromatic hydrocarbon compound, by the Mycobacterium strain 6PY1 was optimized in a biphasic culture medium. The optimization and modeling were performed using the design of
experiments methodology. The temperature, the silicone oil/mineral salts medium volume ratio, and the initial cell concentration,
were used as the central composite design parameters. In all experiments, the phenanthrene was degraded to undetectable levels.
Response surface methodology was successfully employed to derive an empirical model describing the rate and time of degradation
and to deduce the optimal degradation conditions. As a result of the optimization processes, the optimal responses for the
degradation rate, the volumetric degradation rate, and the 90% degradation time were estimated to be 0.172 mg h−1, 22 mg l−1 h−1, and 18 h, respectively. 相似文献
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R. Binato T. de Souza Fernandez C. Lazzarotto‐Silva B. Du Rocher A. Mencalha L. Pizzatti L. F. Bouzas E. Abdelhay 《Cell proliferation》2013,46(1):10-22
Ex vivo expansion and manipulation of human mesenchymal stem cells are important approaches to immunoregulatory and regenerative cell therapies. Although these cells show great potential for use, issues relating to their overall nature emerge as problems in the field. The need for extensive cell quantity amplification in vitro to obtain sufficient cell numbers for use, poses a risk of accumulating genetic and epigenetic abnormalities that could lead to sporadic malignant cell transformation. In this study, we have examined human mesenchymal stem cells derived from bone marrow, over extended culture time, using cytogenetic analyses, mixed lymphocyte reactions, proteomics and gene expression assays to determine whether the cultures would retain their potential for use in subsequent passages. Results indicate that in vitro cultures of these cells demonstrated chromosome variability after passage 4, but their immunomodulatory functions and differentiation capacity were maintained. At the molecular level, changes were observed from passage 5 on, indicating initiation of differentiation. Together, these results lead to the hypothesis that human mesenchymal stem cells cultures can be used successfully in cell therapy up to passage 4. However, use of cells from higher passages would have to be analysed case by case. 相似文献
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Abdelhay Benhalla Mohamed Houssou Moussa Charif 《Bioprocess and biosystems engineering》2010,33(6):759-771
This paper deals with the linearization of the full activated sludge model No 1 (ASM1) in the scope of interaction analysis.
For consistency, the linearization procedure is developed and validated within the BSM1 simulation benchmark framework. It
is based on reaction rate approximation by linear combinations of states. The linear rate models are identified and incorporated
in the mass balance equations, yielding a linear locally equivalent to the ASM1 model. Linear models for anoxic and aerated
compartments are proposed. It is observed that the presented models track very closely the nonlinear ASM1 responses to various
influent data. The key feature of this linearization strategy is that the gotten linear version of the ASM1 model is linear
time invariant (LTI) and that it conserves the states biological interpretation and the original ASM1 dimension. It allows,
therefore, application of interaction analysis methods and makes it possible to determine motivated control configurations
for the ASM1 model. 相似文献