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Cell Biology for Bioprocessing
Published in Wei-Shou Hu, Cell Culture Bioprocess Engineering, 2020
Most cells in tissues in vivo are quiescent, meaning that they are not dividing (Panel 2.2). The quiescent state is not merely the passive result of a lack of conditions necessary for growth, such as a missing essential nutrient. Rather, the quiescent state is imposed on the cell by the regulation of the organism. For example, stem cells in our body are in a quiescent state most of the time, as a result of cell cycle regulation through cyclin-dependent kinase inhibitors, transcription factors, and tumor suppressors. Cells that grow out from tissue explant have undergone changes in their cell growth control mechanism that enable them to proliferate in culture. In some cases, the cells outgrown from isolated tissue can be expanded serially over many passages and still retain normal morphology and cell behavior. They can even be cryopreserved in liquid nitrogen and be “banked” for future research, distribution, or manufacturing purposes. However, such repeated passaging and cell expansion in culture cannot be continued indefinitely. Eventually, senescence is reached. Before senescence, these cells are morphologically normal. Their karyotype is diploid, i.e., having two sets of normal chromosomes. Virtually all normal diploid cells derived from mammal tissues have a limited life span in culture, with the exception of embryonic stem cells and induced pluripotent stem cells.
®” Preserves Wet/Living Organisms for Observation in High Resolution under a Scanning Electron Microscope
Published in Akihiro Miyauchi, Masatsugu Shimomura, Industrial Biomimetics, 2019
To explore the effect of the SSE-based NanoSuit® for “wet-fixed specimens,” observations were carried out on chemically fixed pathology samples. Figure 15.4 shows images of a surgical explant of the human stomach wall including areas of normal and cancerous tissue. Morphological features were compared using two different preparations: specimens treated with the SSE-NanoSuit® solution and specimens prepared by conventional methods for SEM observation (fixation, freeze-drying, and metal coating). Specimens treated with the SSE-NanoSuit® solution (Fig. 15.4) appeared intact. By comparison, fixed specimens prepared by conventional metal coating for SEM showed obvious structural damage (data not shown).
The therapeutic role of the components of Aloe vera in activating the factors that induce osteoarthritic joint remodeling
Published in Badal Jageshwar Prasad Dewangan, Maheshkumar Narsingrao Yenkie, Novel Applications in Polymers and Waste Management, 2018
Abhipriya Chatterjee, Patit Paban Kundu
The function of IGF1 in articular cartilage metabolism has been an interesting subject of investigation in cartilagerelated diseases.75 IGF1 induced a series of anabolic effects and decreased catabolic responses when applied in monolayer or explant culture of normal cartilage from variety of species.76, 77 An in vivo study in rats showed that chronic defi ciency of IGF1 led to articular cartilage lesions which proved the fact that IGF1 is necessary to maintain cartilage integrity.74 Chondrogenic differentiation of mesenchyme stem cells is stimulated by IGF1, but it is reported to be enhanced further when a combination of IGF1 and TGFP1 is used. In animal models, IGF1 has led to enhanced repair of extensive cartilage defects and protection of the synovial membrane from chronic inflammation. However, with age and in osteoarthritis, chondrocytes fail to respond to IGF1.67, 77, 78 In spite of the fact that the ability of IGF1 to decrease catabolism in cartilage goes down with age and in osteoarthritic cartilage, a combination with BMP7 enhances the function of IGF1. Activity of BMP7 does not go down with age or injury, so its combina tion with IGF1 resolves the agerelated lack of property in IGF1.74, 79, 80
Determination of antibiotic impurities in good manufacturing practices-grade cell therapy medicinal products
Published in Preparative Biochemistry & Biotechnology, 2020
Olga Nehir Oztel, Seval Korkmaz, Erdal Karaoz
All samples of human Umbilical Cord Derived MSCs (UC-MSCs) as cell therapy medicinal products were manufactured at the cGMP-certified facility at Liv Hospital Center for Regenerative Medicine and Stem Cell Manufacturing (LivMedCell). Umbilical cords were obtained from consenting patients delivering full-term infants by Cesarean section, who faced no complications throughout pregnancy. Briefly, cords were rinsed using PBS (Invitrogen/Gibco, Paisley, UK), umbilical cord ven and arteries were then removed and the remaining tissue was minced into 1–2 mm3 mm pieces for explant culture. Culture was maintained in MSC NutriStem® XF Basal Medium and MSC NutriStem® XF Supplement Mix (Biological Industries, Cromwell, CT, USA) cell culture media supplied with 2% human serum (SeraCare, Milford, MA, USA) and 50 U/mL P/S (Biological Industries). Cells were grown in a humidified atmosphere containing 5% CO2 at 37 °C and were subcultured until the third passage. Culture medium is replaced every 5 d until fibroblast-like adherent cells reach 70% confluence. For MSC characterization and qualification, the cells were harvested at their third passages, and quality control (QC) tests were performed. In order to manufacture the cell based therapy products, flow cytometry analysis, cell viability assessment, mycoplasma detection, gene expression, telomerase activity, endotoxin and sterility tests were performed as “Valid Quality Control Tests”. Culture media were collected for the detection of antibiotic residues. All samples were tested under seven different groups as listed in Table 1.
Establishment and elicitation of transgenic root culture of Plantago lanceolata and evaluation of its anti-bacterial and cytotoxicity activity
Published in Preparative Biochemistry & Biotechnology, 2021
Samaneh Rahamouz-Haghighi, Khadijeh Bagheri, Ali Sharafi, Hossein Danafar
It is believed that Acetosyringone is one the most potent phenolic inducer associated with the vir genes of Agrobacterium[46] and this signal is transduced by a receptor virA protein located in the inner bacterial cell membrane.[47] In addition to optimal Agrobacterium growth, activation of Agrobacterium vir genes for instance virB, D and virG through virA via the phenolic inducers synthesized by plants such as Acetosyringone[48] is crucial for a successful transformation of Agrobacterium-mediated plant[49] once explant tissue browning is controlled in a good manner.
Enhancement of heavy metal tolerance and accumulation efficiency by expressing Arabidopsis ATP sulfurylase gene in alfalfa
Published in International Journal of Phytoremediation, 2019
V. Kumar, S. AlMomin, A. Al-Shatti, H. Al-Aqeel, F. Al-Salameen, A. B. Shajan, S. M. Nair
Genetic transformation of recalcitrant plant species such as Alfalfa requires optimization of several critical factors. Although there are several reports on the somatic embryogenesis of alfalfa, most reported methods are highly genotype-specific (Walker and Sato 1981; Novak and Konečná 1982; Dijak et al. 1986; Strickland et al. 1987; Hernandez-Fernandez and Christie 1989; Song et al. 1990; Kielly and Bowley 1992; Parrott and Bailey 1993; Shetty and McKersie 1993; Ninković et al. 1995; Shao et al. 2000; Pasternak et al. 2002; Tian et al. 2002; Liu et al. 2013; Fu et al. 2015). Therefore, optimization of the embryogenesis method is a very important factor, prior to any transformation attempt. Here, we report the development and optimization of a protocol to successfully generate transgenic alfalfa plants of the Regen SY genotype, using the somatic embryo-based regeneration method (Fu et al. 2014). The interaction between Agrobacterium and explants during the co-cultivation step is a critical factor affecting genetic transformation. Previous alfalfa transformation protocols involved ultra-sonication of leaf explants to induce micro wounds (Fu et al. 2014). However, this caused bleaching of the explants and permit over-growth of Agrobacteria. Consequently, manual wounding was performed to facilitate Agrobacterium infection in a more controlled manner. Since only a few cells in a plant tissue or organ explant can be genetically transformed using currently available methods, the selective growth of the transformed cells is crucial for the recovery of transgenic plants. The common strategy is that of constitutive expression of a selectable marker gene (Tian et al. 2002); however, we found that kanamycin selection of putative transgenic embryos was very efficient in generating transgenic alfalfa plants.