Objective To investigate the possibility of differentiation of theisolated and cultured adipose-derived adult stem cells into chondrocytes, which is induced by the recombinant human bone morphogenetic protein 2 (rhBMP-2). Methods The rabbit adipose tissue was minced and digested by collagenase Type Ⅰ. The adposederived adult stem cells were obtained and then they were cultured inthe micropellet condition respectively in the rhBMP-2 group, the rhTGF-β1 group, the combination group, and the control group for 14 days. The differentiation of the adiposederived stem cells into chondrocytes was identifiedby the histological methods including HE, Alcian blue, Von kossa, and immunohistochemical stainings. Results After the continuous induction by rhBMP-2 and continuous culture for 14 days, the HE staining revealed a formation of the cartilage lacuna; Alcian blue indicated that proteoglycan existed in the extracellular matrix; the immunohistochemical staining indicated that collagen Ⅱ was in the cellular matrix; and Von kossa indicated that the adipose-derived stem cells couldnot differentiate into the osteoblasts by an induction of rhBMP-2. Conclusion In the micropellet condition, the adipose-derived adult stemcells can differentiate into the chondrocytes, which is initially induced by rhBMP-2. This differentiation can provide a foundation for the repair of the cartilage injury.
Objective To construct chemically extracted acellular nerve allograft (CEANA) with Schwann cells (SCs) from different tissues and to compare the effect of repairing peripheral nerve defect. Methods Bone marrow mesenchymal stem cells (BMSCs) and adi pose-derived stem cells (ADSCs) were isolated and cultured from 3 4-week-old SD mice with weighing 80-120 g. BMSCs and ADSCs were induced to differentiated MSC (dMSC) and differentiated ADSC (dADSC) in vitro.dMSC and dADSC were identified by p75 protein and gl ial fibrillary acidic protein (GFAP). SCs were isolated and culturedfrom 10 3-day-old SD mice with weighing 6-8 g. CEANA were made from bilateral sciatic nerves of 20 adult Wistar mice with weighing 200-250 g. Forty adult SD mice were made the model of left sciatic nerve defect (15 mm) and divided into 5 groups (n=8 per group) according to CEANA with different sources of SCs: autografting (group A), acellular grafting with SCs (5 × 105) (group B), acellular grafting with dMSCs (5 × 105) (group C), acellular grafting with dADSCs (5 × 105) (group D), and acellular grafting alone (group E). Motor and sensory nerve recovery was assessed by Von Frey and tension of the triceps surae muscle testing 12 weeks after operation. Then wet weight recovery ratio of triceps surae muscles was measured and histomorphometric assessment of nerve grafts was evaluated. Results BMSCs and ADSCs did not express antigens CD34 and CD45, and expressed antigen CD90. BMSCs and ADSC were differentiated into similar morphous of SCs and confirmed by the detection of SCs-specific cellsurface markers. The mean 50% withdrawal threshold in groups A, B, C, D, and E was (13.8 ± 2.3), (15.4 ± 6.5), (16.9 ± 5.3), (16.3 ± 3.5), and (20.0 ± 5.3) g, showing significant difference between group A and group E (P lt; 0.01). The recovery of tension of the triceps surae muscle in groups A, B, C, D, and E was 87.0% ± 9.7%, 70.0% ± 6.6%, 69.0% ± 6.7%, 65.0% ± 9.8%, and 45.0%± 12.1%, showing significant differences between groups A, B, C, D, and group E (P lt; 0.05). No inflammatory reactionexisted around nerve graft. The histological observation indicated that the number of myel inated nerve fiber and the myel in sheath thickness in group E were significantly smaller than that in groups B, C, and D (P lt; 0.01). The fiber diameter of group B was significantly bigger than that of groups C and D (P lt; 0.05) Conclusion CEANA supplementing with dADSC has similar repair effect in peripheral nerve defect to supplementing with dMSC or SCs. dADSC, as an ideal seeding cell in nerve tissue engineering, can be benefit for treatment of peripheral nerve injuries.
Objective To review research progress of adipose tissuederived stromal cells (ADSCs).Methods The recent articles on ADSCs were extensively reviewed, and the culture and differentiation ability of ADSCs were investigated.Results A population of stem cells could be isolated from adult adipose tissue, they were processed to obtain a fibroblast-like population of cells and could be maintained in vitro for extended periods with stable population doubling. The majority of the isolated cells were mesenchymal origin, with a few pericytes,endothelial cells and smooth muscle cells. ADSCs could be induced to differentiate intomultiple mesenchymal cell types, including osteogenic, chondrogenic, myogenic and adipogenic cells, they could also differentiate into nerve cells.Conclusion ADSCs can substitute mesenchymal stem cells and become an alternative stem cells source for tissue engineering.
Objective To introduce the related issues in the clinical translational application of adipose-derived stem cells (ASCs). Methods The latest papers were extensively reviewed, concerning the issues of ASCs production, management, transportation, use, and safety during clinical application. Results ASCs, as a new member of adult stem cells family, bring to wide application prospect in the field of regenerative medicine. Over 40 clinical trials using ASCs conducted in 15 countries have been registered on the website (http://www.clinicaltrials.gov) of the National Institutes of Health (NIH), suggesting that ASCs represents a promising approach to future cell-based therapies. In the clinical translational application, the related issues included the quality control standard that management and production should follow, the prevention measures of pathogenic microorganism pollution, the requirements of enzymes and related reagent in separation process, possible effect of donor site, age, and sex in sampling, low temperature storage, product transportation, and safety. Conclusion ASCs have the advantage of clinical translational application, much attention should be paid to these issues in clinical application to accelerate the clinical translation process.
ObjectiveTo investigate the effect of burn on the fat metabolism by observing the effect of burn serum on the proliferation and adipose differentiation of 3T3-L1 preadipocytes. MethodsForty-eight male Sprague Dawley rats were randomly divided into sham burn group and burn at 1, 4, 7, 14, and 21 days groups, 8 rats in each group. The rats in burn groups were made the full-thickness thermal burns comprising 30% total body surface area. At 1, 4, 7, 14, and 21 days after burn, the serum of burn rats was collected. The rats in sham burn group were not treated as normal control. The proliferation activity of 3T3-Ll cells was detected using MTT method after treated by normal and burn serum. The burn serum having the highest proliferation inhibitory effect was chosen for subsequent study. The growth of 3T3-L1 cells in normal serum group (group A), burn serum group (group B), normal serum and adipogenic induction group (group C), burn serum and adipogenic induction group (group D) was observed using inverted microscope. After 7 days of treatment, the adipocytes was stained by oil red O and the absorbance (A) value was measured. The mRNA and protein levels of preoxisome proliferator-activated receptor γ (PPAR-γ) and lipoprotein lipase (LPL) were detected by real-time quantitative PCR and Western blot. ResultsThe proliferation ability of 3T3-L1 cells was significantly reduced in the group treated by 4-or 7-day burn serum (P<0.05), especially 7-day burn serum treatment group (P<0.05). Under inverted microscope, the cell morphology in group A and group B had no obvious change, but a large number of fat cells were observed in group C and a few were observed in group D. The positive or weak positive oil red O staining was observed in group C or group D, respectively. The cell counting and A value were significantly higher in group A than in group B, and in group C than in group D (P<0.05). The mRNA level of PPAR-γ in group B was significantly reduced when compared with that in group A (P<0.05). No significant difference was found in LPL mRNA levels and protein levels of PPAR-γ and LPL between group A and group B (P>0.05). The mRNA and protein levels of PPAR-γ and LPL were significantly attenuated in group D when compared with those in group C (P<0.05). ConclusionThe adipose differentiation of 3T3-L1 preadipocytes can be significantly reduced after treated by 7-day burn serum of rat.
To isolate and culture adi pose-derived stem cells (ADSCs), and to study the effects of the conditioned medium of ADSCs (ADSC-CM) treated with insul in on HaCaT cells. Methods ADSCs were isolated from adipose tissue donated by the patient receiving abdominal surgery and were cultured. The concentration of ADSCs at passage 3 was adjusted to 5 × 104 cells/mL. The cells were divided into 2 groups: group A in which the cells were incubated in 1 × 10-7 mol/ Linsul in for 3 days, and group B in which the cells were not treated with insul in. ADSC-CM in each group was collected 3 days after culture, then levels of VEGF and hepatocyte growth factor (HGF). HaCaT cells were cultured and the cells at passage 4 were divided into 4 groups: group A1, 0.5 mL 2% FBS and 0.5 mL ADSC-CM from group A; group B1, 0.5 mL 2% FBS and 0.5 mL ADSC-CM from group B; group C1, 1 mL 2% FBS of 1 × 10-7 mol/ L insul in; group D1, 1 mL 2%FBS. Prol iferation of HaCaT cells was detected by MTT method 3 days after culture, apoptosis rate of HaCaT cells was measured by Annexin V-FITC double staining 12 hours after culture, and the migration abil ity was measured by in vitro wound-heal ing assay 0, 12, 24, 36 and 48 hours after culture. Results The level of VEGF in groups A and B was (643.28 ± 63.57) and (286.52 ± 46.68) pg/mL, respectively, and the level of HGF in groups A and B was (929.95 ± 67.52) and (576.61 ± 84.29) pg/mL, respectively, suggesting differences were significant between two groups (Plt; 0.05). Cell prol iferation detection showed the absorbance value of HaCaT cells in group A1, B1, C1 and D1 was 0.881 ± 0.039, 0.804 ± 0.041, 0.663 ± 0.027 and 0.652 ± 0.042, respectively, suggesting there was significant difference between groups A1 and B1 and groups C1 and D1 (P lt; 0.01), group A1 was significantly higher than group B1 (P lt; 0.05). The apoptosis rate of HaCaT cells in groups A1, B1, C1 and D1 was 5.23% ± 1.98%, 8.82% ± 2.59%, 31.70% ± 8.85% and 29.60% ± 8.41%, respectively, indicating there was significant difference between groups A1 and B1 and groups C1 and D1 (P lt; 0.05), group B1 was significantly higher than group A1 (P lt; 0.05). The migration distance of HaCaT cells in groups A1, B1,C1 and D1 at 36 hours was (0.184 6 ± 0.019 2), (0.159 8 ± 0.029 4), (0.059 2 ± 0.017 6) and (0.058 2 ± 0.012 3) mm, respectively, whereas at 48 hours, it was (0.231 8 ± 0.174 0), (0.205 1 ± 0.012 1), (0.079 2 ± 0.008 1) and (0.078 4 ± 0.011 7) mm, respectively, suggesting there were significant differences between groups A1 and B1 and groups C1 and D1 at 36 and 48 hours (P lt; 0.01), group A1 was significantly higher than group B1 (P lt; 0.05) at 36 and 48 hours, no significant difference was evident at other time points(P gt; 0.05). Conclusion ADSCs treated with insul in can significantly promote the prol iferation and the migration of HaCaT cells and inhibit their apoptosis.
Objective To find a kind of simple and effective method for purifying and label ing stromal vascular fraction cells (SVFs) so as to provide a theoretical basis for cl inical application of SVFs. Methods The subcutaneous adi pose tissue were harvested form volunteers. The adi pose tissue was digested with 0.065%, 0.125%, and 0.185% type I collagenase,respectively. SVFs were harvested after digestion and counted. After trypan blue staining, the rate of viable cells was observed. SVFs was labeled by 1, 1’-dioctadecyl-3, 3, 3’, 3’-2-tetramethy-lindocyanine perchlorate (DiI). The fluorescent label ing and growth was observed under an inverted fluorescence microscope. MTT assay was used to detect cell proliferation. Results The number of SVFs was (138.68 ± 11.64) × 104, (183.80 ± 10.16) × 104, and (293.07 ± 8.31) × 104 in 0.065% group, 0.125% group, and 0.185% group, respectively, showing significant differences among 3 groups (P lt; 0.01). The rates of viable cells were 91% ± 2%, 90% ± 2%, and 81% ± 2% in 0.065% group, 0.125% group, and 0.185% group, respectively, and it was significantly higher in 0.065% group and 0.125% group than in 0.185% group (P lt; 0.01), but no significant difference was found between 0.065% group and 0.125% group (P=0.881). Inverted fluorescence microscope showed that the cell membranes could be labeled by DiI with intact cell membrane, abundant cytoplasm, and good shape, but nucleus could not labeled. SVFs labeled by DiI could be cultured successfully and maintained a normal form. MTT assay showed that similar curves of the cell growth were observed before and after DiI labeled to SVFs. Conclusion The optimal collagenase concentration for purifying SVFs is 0.125%. DiI is a kind of ideal fluorescent dye for SVFs.
Objective To further study the influence of the co-cultivation of vascular endothel ial cells (VECs) and adi pose-derived stromal cells (ADSCs) on cell osteogenic differentiation in vitro and provide experimental evidences of the probabil ity of the co-cultivation of VECs and ADSCs as the seed cells of tissue engineering. Methods The VECs derived fromcord blood and ADSCs were prepared by full-term pregnancy SD rats and 18-week-old SD rats, to carry on the morphological observation and immunohistochemical staining identification. The third generation of ADSCs and the VECs induced by conditioned medium for 6 weeks were cultured and were divided into groups A, B, and C as the experimental group according to cell ratios of 3 ∶ 1, 1 ∶ 1, and 1 ∶ 3, respectively. ADSCs or VECs was cultured alone in groups D and E as control groups. ALP and al izarin red staining were done respectively on the 7th day and 14th day; ALP and osteocalcin (OC) were detected respectively on the 4th day, 7th day, and 14th day. Results The VECs derived from cord blood showed mixed growth of short spindle and polygonal cells after 6 weeks of induction, the immunofluorescent staining result of von Willebrand factor was positive. ADSCs showed adherent mononuclear cells and spindle-shaped growth without dupl ication; the immunofluorescent staining result of CD90 was positive and no positive cells were seen in the control group. On the 7th day of cell culture, ALP staining showed that the results were negative in groups A, D, and E, and some positive cells were seen in groups B and C; on the 14th day, the results were still negative in groups D and E, and positive cells fused to sheet form in groups A, B, and C. von Kossa staining showed that the results were negative in all groups on the 7th day; few positve cells were seen in groups A, B, and C, and no positive cells were seen in groups D and E on the 14th day. The ALP contents increased gradually in all groups,which was highest in group B at every time point, showing significant difference (P lt; 0.01) between group B and other groups, between groups A, C and groups D, E. The OC value increased gradually in every group, which was highest in group B on the 7th and 14th days, showing significant difference between group B and other groups (P lt; 0.01), between group C and group D (P lt; 0.01) on the 4th and the 14th days, between groups A, C and group E (P lt; 0.05) on the 14th day. Conclusion ADSCs have potential of osteogenic differentiation by VECs in the system of co-culturing VECs and ADSCs in vitro, the influence on osteogenic differentiation is the best in a ratio of 1 ∶ 1.
ObjectiveTo review the research progress of constructing injectable tissue engineered adipose tissue by adipose-derived stem cells (ADSCs). MethodsRecent literature about ADSCs composite three-dimensional scaffold to construct injectable tissue engineered adipose tissue is summarized, mainly on the characteristics of ADSCs, innovation of injectable scaffold, and methods to promote blood supply. ResultsADSCs have a sufficient amount and powerful ability such as secretion, excellent compatibility with injectable scaffold, plus with methods of promoting blood supply, which can build forms of injectable tissue engineered adipose tissue. ConclusionIn despite of many problems to be dealt with, ADSCs constructing injectable tissue engineered adipose tissue may provide a promising source for soft-tissue defect repair and plastic surgery.
Objective To compare two kinds of myofascial flap encapsulating adi pose-derived stromal cells (ADSCs) in adi pogenic efficacy in vivo, and to provide experimental basis for the efficient transplantation of free adi pose tissue. Methods ADSCs were isolated from the subcutaneous adipose tissue in the neck of 10 New Zealand rabbits (aged 3-4 months old, male and female, weighing 2.0-2.5 kg), and primary culture and subculture of ADSCs were conducted. When the cells at passage 3 covered 70%-80% of the bottom of the culture flask, BrdU (10 μg/mL) was appl ied to label the cells for 48 hours before performing immunofluorescence staining. Oil red O staining observation was conducted to thosecells 2 weeks after being induced towards adi pocyte, al izarin red staining observation was performed 3 weeks after being induced towards osteoblast, and alcian blue staining was conducted 2 weeks after being induced towards chondrocyte. Besides, after being induced towards adipocyte for 2 weeks, 1 × 107 ADSCs/piece at passage 3 labeled by BrdU was seeded into Col I (10 mm × 10 mm × 5 mm/piece) to prepare cell carrier complex. The experiment was divided into two groups: group A in which vascular pedicled dextral latissimus dorsi fascial flap was adopted to encapsulate the complex; group B in which dextral gluteus maximus fascial flap with no specific vessel pedicle was appl ied to encapsulate the complex. Rabbits in each group went through autogenous ADSCs transplant and self control. The implants were dislodged 8 weeks after operation, HE staining and immunohistochemistry staining were performed to testify cambium, the wet weight and micro vessel count of the cambium in each group were tested, immunofluorescence staining was performed to determine the origin of cambium and microvascular endothel ium. Results The nucleus of ADSCs positive for BrdU label ing showed green fluorescence under fluorescence microscope, with the positive label ing ratio of ADSCs above 90%. For ADSCs at passage 3, the formation of red l ipid droplets within cells was observed 2 weeks after being induced towards adipocyte, red calcium nodules were evident 3 weeks after being induced towards osteoblast, and highly congregated cell mass positive for alcian blue staining appeared 2 weeks after being induced towards chondrocyte. Eight weeks after operation, neogenetic blood vessel grew into scaffolds and no obvious fibreencapsulation was observed in group A, while few blood vessel grew into scaffolds in group B. The wet weight of cambium in group A and B was (0.149 5 ± 0.017 3) g and (0.095 3 ± 0.012 7) g, respectively, indicating there was a significant difference between two groups (P lt; 0.01). HE staining showed the formation of neogenetic adipose tissue and the growth of micrangium in the implant, and the degradation and absorption of scaffold. The micro vessel count of group A and B was 31.2 ± 4.5 and 19.3 ± 2.6, respectively, indicating there was a significant difference between two groups (P lt; 0.01). Eight weeks after operation, the immunofluorescence staining of cambium showed that the cell nucleus of regenerated adi pocytes and partial capillary endothel ium in groups A and B presented green fluorescence. Conclusion ADSCs encapsulated by vascular pedicled latissimus dorsi fascial flap and collagen protein scaffold complex has a higher adi pogenic efficacy in vivo than the gluteus maximus fascial flap with no specific vessel pedicle.