ABSTRACT
BACKGROUND:In 2001, Zuk et al found adipose-derived stem cels (ASCs) from the aspirate of liposuction for the first time, which launched a new era of stem cel research. In recent years, stem cels have been proved to widely exist in many tissues and organs. ASCs are always in the spotlight of plastic and reconstructive surgery, tissue engineering and regenerative medicine because of extensive sources and simple isolation. OBJECTIVE: To review the fat tissue harvesting and ASCs isolation, purification, expansion, and cryopreservation, to discuss the main factors which influence the yield, proliferation capacity and differentiation potential of ASCs, and to predict the future research interests based on current issues. METHODS:On September 10th, 2015, relevant articles were searched in PubMed using the folowing format: (adipose stem cels[Title]) OR (adipose-derived stem cels[Title]) OR (adipose-derived mesenchymal stem cels[Title]) and in SinoMed using the folowing format in Chinese: (“adipose-derived stem cels” [Title])or(“adipose-derived mesenchymal stem cels”[Title]). Finaly, 81 representative articles were included according to their titles and abstracts. In this review, we also introduced relevant experience about the aforementioned procedures from the Department of Plastic Surgery and Tissue Regeneration and Molecular Cel Engineering Lab of University of Texas, MD Anderson Cancer Center, USA. RESULTS AND CONCLUSION:The widely dispersed fat tissues potentialy provide abundant stem cels for tissue engineering and regenerative medicine. Liposuction is a mini-invasive approach for harvesting fat tissues. Colagenase digestion is the major method for ASCs isolation due to its simplicity and high yield in basic research. However, clinical fat transplantation without ASCs isolation or non-colagenase isolation of stromal vascular fraction or ASCs is preferred. The phenotype, proliferation and differentiation capacity of ASCs may be affected by several factors during the fat tissue harvesting and ASCs isolation. Therefore, a standard protocol for ASCs isolation is needed.
ABSTRACT
BACKGROUND:Rabbit bone marrow mesenchymal stem cels as a kind of adult stem cels with strong proliferation and multilineage differentiation potential exhibit a tremendous application potential in tissue engineering and biological therapy. OBJECTIVE:To in vitro culture, proliferate and identify rabbit bone marrow mesenchymal stem cels and to observe cel biological characteristics. MEHTODS:Bone marrow of rabbits was extracted under sterile conditions to separate bone marrow mesenchymal stem cels using the whole bone marrow adherence method and Percol density gradient centrifugation method. Afterwards, the cels were purified and proliferated using differential adherence method. Morphology and growth pattern of cels were observed under microscope, and expression of cel surface antigen markers was detected by flow cytometry. RESULTS AND CONCLUSION:Rabbit bone marrow mesenchymal stem cels presented with short adherent time and fast growth. After passage and purification, impurities cel counts were decreased. Primary cels presented with triangular, fusiform and spindly shapes. Passage 5 cels with single shape showed the typical polar swirling growth, and could not express CD34 and CD45, but expressed CD29 and CD44. These findings indicate that the cels cultured using the whole bone marrow adherence method and Percol density gradient centrifugation method possess stem cel characteristics in morphology, surface markers and multilineage differentiation, which have been identified as bone marrow mesenchymal stem cels by flow cytometry.
ABSTRACT
BACKGROUND:Mesenchymal stem cel s as potential seeded cel s have been widely used in tissue engineering and clinic therapy;thus, the precise, safe, effective isolation of mesenchymal stem cel s is the particular important premise to build culture system. OBJECTIVE:To review the methods of isolating mesenchymal stem cel s and to compare the merit and demerit of different methods, thereby providing theoretical basis for safe and high-effective isolation of mesenchymal stem cel s. METHODS:A computer-based online research of CNKI and PubMed databases was performed to col ect articles, which included reviews, clinical trials and experiments, published between 1965 and 2014 with the key words of“mesenchymal stem cel s (MSCs), isolation methods”in Chinese and English. A total of 52 articles were included according inclusion and exclusion criteria RESULTS AND CONCLUSION:(1) The whole bone marrow culture method can derive a mass of mesenchymal stem cel s, which need to be purified. (2) The density gradient centrifugation method which uses the media with the density of 1.073 g/mL can be used to harvest more purified cel s. (3) The tissue digestion method is suitable for digestion and isolation of adipose tissue and umbilical cord tissue. Type II col agenase digestion is better, but they are both limited by a high demand for operative techniques. (4) Immunomagnetic bead separation is appropriate to study the biological characteristics of a kind of subpopulation of mesenchymal stem cel s which express special surface markers. (5) The combination method is also an optimal way. (6) Some new methods limited by few dates require further studies.