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Proliferation Ability (proliferation + ability)
Selected AbstractsIsolation of human foetal myoblasts and its application for microencapsulationJOURNAL OF CELLULAR AND MOLECULAR MEDICINE, Issue 1 2008Anna Aihua Li Abstract Foetal cells secrete more growth factors, generate less immune response, grow and proliferate better than adult cells. These characteristics make them desirable for recombinant modification and use in microencapsulated cellular gene therapeutics. We have established a system in vitro to obtain a pure population of primary human foetal myoblasts under several rounds of selection with non-collagen coated plates and identified by desmin staining. These primary myoblasts presented good proliferation ability and better differentiation characteristics in monolayer and after microencapsulation compared to murine myoblast C2C12 cells based on creatine phosphokinase (CPK), major histocompatibility complex (MHC) and multi-nucleated myotubule determination. The lifespan of primary myoblasts was 70 population doublings before entering into senescent state, with a population time of 18,24 hrs. Hence, we have developed a protocol for isolating human foetal primary myoblasts with excellent differentiation potential and robust growth and longevity. They should be useful for cell-based therapy in human clinical applications with microencapsulation technology. [source] MRG15, a component of HAT and HDAC complexes, is essential for proliferation and differentiation of neural precursor cellsJOURNAL OF NEUROSCIENCE RESEARCH, Issue 7 2009Meizhen Chen Abstract Neurogenesis during development depends on the coordinated regulation of self-renewal and differentiation of neural precursor cells (NPCs). Chromatin regulation is a key step in self-renewal activity and fate decision of NPCs. However, the molecular mechanism or mechanisms of this regulation is not fully understood. Here, we demonstrate for the first time that MRG15, a chromatin regulator, is important for proliferation and neural fate decision of NPCs. Neuroepithelia from Mrg15 -deficient embryonic brain are much thinner than those from control, and apoptotic cells increase in this region. We isolated NPCs from Mrg15 -deficient and wild-type embryonic whole brains and produced neurospheres to measure the self-renewal and differentiation abilities of these cells in vitro. Neurospheres culture from Mrg15 -deficient embryo grew less efficiently than those from wild type. Measurement of proliferation by means of BrdU (bromodeoxyuridine) incorporation revealed that Mrg15 -deficient NPCs have reduced proliferation ability and apoptotic cells do not increase during in vitro culture. The reduced proliferation of Mrg15 -deficient NPCs most likely accounts for the thinner neuroepithelia in Mrg15 -deficient embryonic brain. Moreover, we also demonstrate Mrg15 -deficient NPCs are defective in differentiation into neurons in vitro. Our results demonstrate that MRG15 has more than one function in neurogenesis and defines a novel role for this chromatin regulator that integrates proliferation and cell-fate determination in neurogenesis during development. © 2008 Wiley-Liss, Inc. [source] Immunohistochemical comparison of ,-catenin expression by human normal epidermis and epidermal tumorsTHE JOURNAL OF DERMATOLOGY, Issue 11 2007Keiko FUKUMARU ABSTRACT ,-Catenin, a cytoplasmic protein that binds directly to the intracellular domain of cadherin, controls various functions such as cell adhesion. In many human carcinomas, E-cadherin-mediated cell,cell adhesion is lost or disturbed and related to metastasis. The purpose of this study was to compare the expression of ,-catenin in the normal epidermal keratinocytes and samples from cutaneous benign and malignant epidermal tumors in 140 patients. Our study population consisted of 140 patients with benign or malignant epidermal tumors. Using immunohistochemical methods, we compared the expression of ,-catenin in their normal epidermal keratinocytes, and in samples from 61 benign (seborrheic keratosis, n = 33; verruca vulgaris, n = 14; keratoacanthoma, n = 14), and 79 malignant (Bowen's disease, n = 18; basal cell carcinoma, n = 33; squamous cell carcinoma, n = 28) epidermal tumors. ,-Catenin was found to be expressed in the cell membrane of normal keratinocytes. Compared to other cell components of the normal epidermis, basal cells showed the strongest ,-catenin expression in all 140 patients. While absent in three of 61 benign tumors, compared to normal basal cells, the expression of ,-catenin in the other 58 tumors was not significantly different; it was reduced in 71 of 79 malignant tumors (P < 0.0001). In Bowen's disease, the expression of ,-catenin on the tumor cell membrane was reduced, however, strong expression was seen in the nuclei and cytoplasm. Our results suggest that ,-catenin expression on the membrane of keratinocytes is associated with the differentiation of normal keratinocytes but not with their stage of differentiation, nor with the proliferation ability of epidermal tumor cells. [source] Adipose-derived stem cell: a better stem cell than BMSCCELL BIOCHEMISTRY AND FUNCTION, Issue 6 2008Yanxia Zhu Abstract To further study the proliferation and multi-differentiation potentials of adipose-derived stem cells (ADSCs), the cells were isolated with improved methods and their growth curves were achieved with cck-8. Surface protein expression was analyzed by flow cytometry to characterize the cell phenotype. The multi-lineage potential of ADSCs was testified by differentiating cells with adipogenic, chondrogenic, osteogenic, and myogenic inducers. The results showed that about 5,×,105 stem cells could be obtained from 400 to 600,mg adipose tissue. The ADSCs can be continuously cultured in vitro for up to 1 month without passage and they have several logarithmic growth phases during the culture period. Also, the flow cytometry analysis showed that ADSCs expressed high levels of stem cell-related antigens (CD13, CD29, CD44, CD105, and CD166), while did not express hematopoiesis-related antigens CD34 and CD45, and human leukocyte antigen HLA-DR was also negative. Moreover, stem cell-related transcription factors, Nanog, Oct-4, Sox-2, and Rex-1 were positively expressed in ADSCs. The expression of alkaline phosphatase (ALP) was detected in the early osteogenic induction and the calcified nodules were observed by von Kossa staining. Intracellular lipid droplets could be observed by Oil Red staining. Differentiated cardiomyocytes were observed by connexin43 fluorescent staining. In order to obtain more stem cells, we can subculture ADSCs every 14 days instead of the normal 5 days. ADSCs still keep strong proliferation ability, maintain their phenotypes, and have stronger multi-differentiation potential after 25 passages. Copyright © 2008 John Wiley & Sons, Ltd. [source] | |||||||||||||