注重实践 强调综合 凸显思维——《树叶中的比》教学实录与反思

一、提出问题（播放歌曲《一叶知秋》）。师：同学们,知道这首歌吗？对,它就是2007年＂快乐男声＂全国总冠军陈楚生演唱的《一叶知秋》。（课件出示：一叶知秋。）师：＂一叶知秋＂还是个成语,什么意思呢？语文老师会怎么讲呢？（学生讨论回答。）师：那么,从数学的角度来看这＂一叶＂,又能知道些什么呢？今天,我们就一起来研究树叶。（板书：树叶）（课件出示柳树、香樟图片,聚焦两种树叶。）

Preliminary Study on Biological Properties of Adult Human Bone Marrow-derived Mesenchymal Stem Cells

Objective： To establish a method of culture and expansion of adult human bone marrow-derived MSCs in vitro and to explore their biological properties. Methods： Mononuclear cells were obtained from 5 mL adult human bone marrow by density gradient centrifugation with Percoll solution. Adult human MSCs were cultured in Dulbecco＇s Modified Eagle＇s Medium with low glucose （LG-DMEM） containing 10% fetal calf serum at a density of 2×10^5 cell/cm^2. The morphocytology was observed under phase-contrast microscope. The cell growth was measured by MTT method. The flow cytometer was performed to examine the expression of cell surface molecules and cell cycle. The ultrastructure of MSCs was observed under transmission electron microscope. The immunomodulatory functions of MSCs were measured by MTT method. The effects of MSCs on the growth of K562 cells and the dynamic change of HA, IV-C, LN concentration in the culture supernatant of MSCs was also observed. Results： The MSCs harvested in this study were homogenous population and exhibited a spindle-shaped fibroblastic morphology. The cell growth curve showed that MSCs had a strong ability of proliferation. The cells were positive for CD44, while negative for hematopoietic cell surface marker such as CD3, CD4, CD7, CD13, CD14, CD15, CD19, CD22, CD33, CD34, CD45 and HLA-DR, which was closely related to graft versus host disease. Above 90% cells of MSCs were found at G0/G1 phase. The ultrastructure of MSCs indicated that there were plenty of cytoplasmic organelles. Allogeneic peripheral blood lymphocytes proliferation was suppressed by MSCs and the inhibition ratio was 60.68% （P〈0.01）. The suppressive effect was also existed in the culture supernatant of MSCs and the inhibition ratio was 9.00% （P〈0.05）. When lymphocytes were stimulated by PHA, the suppression effects of the culture supernatant were even stronger and the inhibition ratio was 20.91% （P〈0.01）. Compared with the cell growth curve of the K562 ceils alone, the K562 ceils cocultured with MSCs grew slowly and the exponential phase of growth wasn＇t significant. Seeing from the concentration curve, as time passed, the concentration of HA increased quickly, while those of IV-C and LN didn＇t change much. Conclusion： The method for culture and expansion of adult human bone marrow-derived MSCs in vitro has been successfully established in this study. MSCs were a homogenous population that had unique growth phenotype and multilineage potential. Preliminary study proved that it had the abilities of immunomodulatory function, antitumor, hematopoietic supporting and could act as seed cell of tissue engineering.

王人美的倾城之恋

她就是三十年代红极一时的女星王人美。

Two New ent-Kauranoids from Isodon tenuifolia

Two new ent-kauranoids, tenuifolin A (3beta,6alpha, 15beta-trihydroxy-1alpha, 7beta-diacetoxy-11beta, 16beta-epoxy-ent-kaurane) (1) and tenuifolin B (1alpha,6alpha, 11beta-trihydroxy-3beta,7beta-diacetoxy-ent-kaur-16-en-15-one) (2), together with four known compounds were isolated from the aerial parts of Isodon tenuifolia (W. W. Smith) Kudo collected from Zhongdian County, Yunnan Province, China. Their structures were determined by the spectral methods (including 2D NMR techniques).

Hepatocytic differentiation of mesenchymal stem cells in cocultures with fetal liver cells

AIM： To investigate the hepatocytic differentiation of mesenchymal stem cells （MSCs） in co-cultures with fetal liver cells （FLC） and the possibility to expand differentiated hepatocytic cells. METHODS： MSCs were marked with green fluorescent protein （GFP） by retroviral gene transduction. Clonal marked MSCs were either cultured under liver stimulating conditions using fibronectin-coated culture dishes and medium supplemented with stem cell factor （SCF）, hepatocyte growth factor （HGF）, epidermal growth factor （EGF）, and fibroblast growth factor 4 （FGF-4） alone, or in presence of freshly isolated FLC. Cells in co-cultures were harvested, and GFP＋ or GFP- cells were separated using fluorescence activated cell sorting. Reverse transcription-polymerase chain reaction （RT-PCR） for the liver specific markers cytokeratin-18 （CK-18）, albumin, and alpha-fetoprotein （AFP） was performed in different cell populations. RESULTS- Under the specified culture conditions, rat MSCs co-cultured with FLC expressed albumin, CK-18, and AFP-RNA over two weeks. At wk 3, MSCs lost hepatocytic gene expression, probably due to overgrowth of the cocultured FLC. FLC also showed a stable liver specific gene expression in the co-cultures and a very high growth potential. CONCLUSION： The rat MSCs from bone marrow can differentiate hepatocytic cells in the presence of FLC in vitro and the presence of MSCs in co-cultures also prorides a beneficial environment for expansion and differentiation of FLC.

Human bone marrow-derived mesenchymal stem cells transplanted into damaged rabbit heart to improve heart function

Objective: The present study was designed to test whether transplantation of human bone marrow-derived mesen- chymal stem cells (hMSCs) in New Zealand rabbits with myocardial infarction can improve heart function; and whether engrafted donor cells can survive and transdifferentiated into cardiomyocytes. Methods: Twenty milliliters bone marrow was obtained from healthy men by bone biopsy. A gradient centrifugation method was used to separate bone marrow cells (BMCs) and red blood cells. BMCs were incubated for 48 h and then washed with phosphate-buffered saline (PBS). The culture medium was changed twice a week for 28 d. Finally, hematopoietic cells were washed away to leave only MSCs. Human MSCs (hMSCs) were premarked by BrdU 72 h before the transplantation. Thirty-four New Zealand rabbits were randomly divided into myocardial infarction (MI) control group and cell treated group, which received hMSCs (MI+MSCs) through intramyocardial injection, while the control group received the same volume of PBS. Myocardial infarction was induced by ligation of the left coronary artery. Cell treated rabbits were treated with 5×106 MSCs transplanted into the infarcted region after ligation of the coronary artery for 1 h, and the control group received the same volume of PBS. Cyclosporin A (oral solution; 10 mg/kg) was provided alone, 24 h before surgery and once a day after MI for 4 weeks. Echocardiography was measured in each group before the surgery and 4 weeks after the surgery to test heart function change. The hearts were harvested for HE staining and immunohistochemical studies after MI and cell transplantation for 4 weeks. Results: Our data showed that cardiac function was significantly improved by hMSC transplan- tation in rabbit infarcted hearts 4 weeks after MI (ejection fraction: 0.695±0.038 in the cell treated group (n=12) versus 0.554±0.065 in the control group (n=13) (P<0.05). Surviving hMSCs were identified by BrdU positive spots in infarcted region and transdifferentiated into cardiomyocytes characterized with a positive cardiac phenotype: troponin I. Conclusion: Transplan- tation of hMSCs could transdifferentiate into cardiomyocytes and regenerate vascular structures, contributing to functional im- provement.

Suppression of tumorigenesis by human mesenchymal stem cells in a hepatoma model

Human mesenchymal stem cells （hMSCs） can home to tumor sites and inhibit the growth of tumor cells. Little is known about the underlying molecular mechanisms that link hMSCs to the targeted inhibition of tumor cells. In this study, we investigated the effects of hMSCs on two human hepatoma cell lines （H7402 and HepG2） using an animal transplantation model, a co-culture system and conditioned media from hMSCs. Animal transplantation studies showed that the latent time for tumor formation was prolonged and that the tumor size was smaller when SCID mice were injected with H7402 cells and an equal number of Z3 hMSCs. When co-cultured with Z3 cells, H7402 cell proliferation decreased, apoptosis increased, and the expression of Bcl-2, c-Myc, proliferating cell nuclear antigen （PCNA） and survivin was downregulated. After treatment with conditioned media derived from Z3 hMSC cultures, H4702 cells showed decreased colony-forming ability and decreased proliferation. Immunoblot analysis showed that β-catenin, Bcl-2, c-Myc, PCNA and survivin expression was downregulated in H7402 and HepG2 cells. Taken together, our findings demonstrate that hMSCs inhibit the malignant phenotypes of the H7402 and HepG2 human liver cancer cell lines, which include proliferation, colony-forming ability and oncogene expression both in vitro and in vivo. Furthermore, our studies provide evidence that the Wnt signaling pathway may have a role in hMSC-mediated targeting and tumor cell inhibition.

Differentiation of hepatocytoid cell induced from whole-bone-marrow method isolated rat myeloid mesenchymal stem cells

AIM： To explore the expansion and differentiation of hepatocytoid cell induced from myeloid mesenchymal stem cell （MSC） in vib＇o, in order to find suitable resource of hepatocytes for bioartiflcial liver or liver transplantation. METHODS： The rat myeloid MSC was isolated and divided into three groups which were cultured by Friedensteion method, and then were induced by culture fluid, culture fluid plus cholestatic serum and culture fluid plus hepatocyte growth factor （HGF）, respectively. Hepatocytoid cell as well as expression of CK18 and AFP was observed by immunohistochemistry. RESULTS： After the induction for 21 d, hepatocytoid cell was observed, and its expression of CK18 and AFP was detected by immunohistochemistry in MSC cultured with cholestatic serum. Furthermore, on the 35^th d, albumin mRNA was expressed in the cell, suggesting the inducing effect was similar to that by HGF.CONCLUSION： Rat myeloid MSC can differentiate into hepatocyte lineage under appropriate condition. This method is easy to operate.

Ex vivo expansion and pluripotential differentiation of cryopreserved human bone marrow mesenchymal stem cells

This study is aimed at investigating the potentials of ex vivo expansion and pluri-differentiation of cryopreservation of adult human bone marrow mesenchymal stem cells （hMSCs） into chondrocytes, adipocytes and neurocytes. Cryopreserved hMSCs were resuscitated and cultured for 15 passages, and then induced into chondrocytes, adipocytes and neurocytes with corresponding induction medium. The induced cells were observed for morphological properties and detected for expressions of type II collagen, triglyceride or neuron-specific enolase and nestin. The result showed that the resuscitated cells could differentiate into chondrocytes after exposure to transforming growth factor 61 （TGF-~0, insulin-like growth factor I （IGF-I） and vitamin C （Vc）, and uniformly changed morphologically from a spindle-like fibroblastic appearance to a polygonal shape in three weeks. The induced cells were heterochromatic to safranin O and expressed cartilage matrix-procollagenal （If） mRNA. The resuscitated cells cultured in induction medium consisting of dexamethasone, 3-isobutyl-l-methylxanthine, indomethacin and IGF-I showed adipogenesis, and lipid vacuoles accumulation was detectable after 21 d. The resuscitated hMSCs were also induced into neurocytes and expressed nestin and neuron specific endolase （NSE） that were special surface markers associated with neural cells at different stage. This study suggested that the resuscitated hMSCs should be still a population ofpluripotential cells and that it could be used for establishing an abundant bMSC reservoir for further experiment and treatment of various clinical discases.

5-Azacytidine induces changes in electrophysiological properties of human mesenchymal stem cells

Previously, mouse bone marrow-derived stem cells （MSC） treated with the unspecific DNA methyltransferase inhibitor 5-azacytidine were reported to differentiate into cardiomyocytes. The aim of the present study was to investigate the efficiency of a similar differentiation strategy in human mononuclear cells obtained from healthy bone marrow donors. After 1-3 passages, cultures were exposed for 24 h to 5-azacytidine （3 μM） followed by 6 weeks of further culture. Drug treatment did not induce expression of myogenic marker MyoD or cardiac markers Nkx2.5 and GATA-4 and did not yield beating cells during follow-up. In patch clamp experiments, approximately 10-15% of treated and untreated cells exhibited L-type Ca^2＋ currents. Almost all cells showed outwardly rectifying K^＋ currents of rapid or slow activation kinetics. Mean current amplitude at ＋60 mV doubled after 6 weeks of treatment compared with time-matched controls. Membrane capacitance of treated cells was significantly larger than in controls 2 weeks after treatment and remained high after 6 weeks, Expression levels of mRNAs for the K^＋ channels Kv 1,1, Kv 1,5, Kv2,1, Kv4,3 and KCNMA 1 and for the Ca^2＋ channel Cav 1.2 were not affected by 5-azacytidine. Treatment with potassium channel blockers tetraethylammonium and clofilium at concentrations shown previously to inhibit rapid or slowly activating K^＋ currents of hMSC inhibited proliferation of these cells. Our results suggest that despite the absence of differentiation ofhMSC into cardiomyocytes, treatme.nt with 5-azacytidine caused profound changes in current density.

Autologous transplantation of bone marrow mesenchymal stem cells on diabetic patients with lower limb ischemia

Objective： To study the efficacy and safety of autologous transplantation of bone marrow mesenchymal stem cells on diabetic patients with lower limb ischemia. Methods： Fifty Type 2 diabetic patients with lower limb ischemia were enrolled and randomized to either transplanted group or control group. Patients in both group received the same conventional treatment. Meanwhile, 20 ml bone marrow from each transplanted patient were collected, and the mesenchymal stem cells were separated by density gradient centrifugation and cultured in the medium with autologous serum. After three-weeks adherent culture in vitro, 7.32×10^8-5.61×10^9 mesenchymal stem cells were harvested and transplanted by multiple intramuscular and hypodermic injections into the impaired lower limbs. Results： At the end of 12-week follow-up, 5 patients were excluded from this study because of clinical worsening or failure of cell culture. Main ischemic symptoms, including rest pain and intermittent claudication, were improved significantly in transplanted patients. The ulcer healing rate of the transplanted group （1 5 of 18, 83.33%） was significantly higher than that of the control group （9 of 20, 45.00%, P=0.012）.The mean of resting ankle-brachial index （ABI） in transplanted group significantly was increased from 0.61±0.09 to 0.74±0.11 （P〈0.001）. Magnetic resonance angiography （MRA） demonstrated that there were more patients whose score of new vessels exceeded or equaled to 2 in the transplant patients （11 of 15） than in control patients （2 of 14, P=0.001）. Lower limb amputation rate was significantly lower in transplanted group than in the control group （P=0.040）. No adverse effects was observed in transplanted group. Conclusion： These results indicate that the autologous transplantation of bone marrow mesenchymal stem cells relieves critical lower limb ischemia and promotes ulcers healing in Type 2 diabetic patients.

A critical role of IFNγ in priming MSC-mediated suppression of T cell proliferation through up-regulation of BT-H1

Bone-marrow-derived mesenchymal stem cells （MSCs） have been shown to possess immunosuppressive properties, e.g., by inhibiting T cell proliferation. Activated T cells can also enhance the immunosuppression ability of MSCs. The precise mechanisms underlying MSC-mediated immunosuppression remain largely undefined, although both cell-cell contact and soluble factors have been implicated; nor is it clear how the immunosuppressive property of MSCs is modulated by T cells. Using MSCs isolated from mouse bone marrow, we show here that interferon gamma （IFNγ）, a well-known proinflammatory cytokine produced by activated T cells, plays an important role in priming the immunosuppressive property of MSCs. Mechanistically, IFNγ acts directly on MSCs and leads to up-regulation of B7-H1, an inhibitory surface molecule in these stem cells. MSCs primed by activated T cells derived from IFNγ-/- mouse exhibited dramatically reduced ability to suppress T cell proliferation, a defect that can be rescued by supplying exogenous IFNγ. Moreover, siRNA-mediated knockdown of B7-H1 in MSCs abolished immunosuppression by these cells. Taken together, our results suggest that IFNγ plays a critical role in triggering the immunosuppresion by MSCs through upregulating B7-H1 in these cells, and provide evidence supporting the cell-cell contact mechanism in MSC-mediated immunosuppression.

Inflammatory bowel disease: Moving toward a stem cell-based therapy

The incidence and prevalence of Crohn's disease (CD) and ulcerative colitis (UC), the two major forms of inflammatory bowel diseases (IBD), are rising in western countries. The modern hygienic lifestyle is probably at the root of a disease where, in genetically susceptible hosts, the intestinal commensal flora triggers dysregulated immune and inflammatory responses. Current therapies ranging from anti-inflammatory drugs to immunosuppressive regimens, remain inadequate. Advances in our understanding of the cell populations involved in the pathogenetic processes and recent findings on the regenerative, trophic and immunoregulatory potential of stem cells open new paths in IBD therapy. Hematopoietic and mesenchymal stem cells are catalyzing the attention of IBD investigators. This review highlights the pivotal fi ndings for stem cell-based approaches to IBD therapy and collects the encouraging results coming in from clinical trials.

Hepatogenic differentiation of human mesenchymal stem cells from adipose tissue in comparison with bone marrow mesenchymal stem cells

AIM： To investigate and compare the hepatogenic transdifferentiation of adipose tissue-derived stem cells （ADSC） and bone marrow-derived mesenchymal stem cells （BMSC） in vitro. Transdifferentiation of BMSC into hepatic cells in vivo has been described. Adipose tissue represents an accessible source of ADSC, with similar characteristics to BMSC. METHODS： BMSCs were obtained from patients undergoing total hip arthroplasty and ADSC from human adipose tissue obtained from lipectomy. Cells were grown in medium containing 15% human serum. Cultures were serum deprived for 2 d before cultivating under similar pro-hepatogenic conditions to those of liver development using a 2-step protocol with sequential addition of growth factors, cytokines and hormones. Hepatic differentiation was RT-PCR-assessed and liver-marker genes were immunohistochemically analysed.RESULTS： BMSC and ADSC exhibited a fibroblastic morphology that changed to a polygonal shape when cells differentiated. Expression of stem cell marker Thyl decreased in differentiated ADSC and BMSC. However, the expression of the hepatic markers, albumin and CYPs increased to a similar extent in differentiated BMSC and ADSC. Hepatic gene activation could be attributed to increased liver-enriched transcription factors （C/EBPβ and HNF4α）, as demonstrated by adenoviral expression vectors.CONCLUSION： Mesenchymal stem cells can be induced to hepatogenic transdifferentiation in vitro. ADSCs have a similar hepatogenic differentiation potential to BMSC, but a longer culture period and higher proliferation capacity. Therefore, adipose tissue may be an ideal source of large amounts of autologous stem cells, and may become an alternative for hepatocyte regeneration, liver cell transplantation or preclinical drug testing.

Liver-specific gene expression in mesenchymal stem cells is induced by liver cells

AIM： The origin of putative liver cells from distinct bone marrow stem cells, e.g. hematopoietic stem cells or multipotent adult progenitor cells was found in recent in vitro studies. Cell culture experiments revealed a key role of growth factors for the induction of liver-specific genes in stern cell cultures. We investigated the potential of rat mesenchymal stem cells （MSC） from bone marrow to differentiate into hepatocytic cells in vitro. Furthermore, we assessed the influence of cocultured liver cells on induction of liver-specific gene expression. METHODS： Mesenchymal stem cells were marked with green fluorescent protein （GFP） by retroviral gene transduction. Clonal marked MSC were either cultured under liver stimulating conditions using fibronectin-coated culture dishes and medium supplemented with SCF, HGF, EGF, and FGF-4 alone, or in presence of freshly isolated rat liver cells. Cells in cocultures were harvested and GFP＋ or GFP- cells were separated using fluorescence activated cell sorting. RT-PCR analysis for the stem cell marker Thyl and the hepatocytic markers CK-18, albumin, CK-19, and AFP was performed in the different cell populations. RESULTS： Under the specified culture conditions, rat MSC cocultured with liver cells expressed albumin-, CK-18, CK-19, and AFP-RNA over 3 weeks, whereas MSC cultured alone did not show liver specific gene expression, CONCLUSION： The results indicate that （1） rat MSC from bone marrow can differentiate towards hepatocytic lineage in vitro, and （2） that the microenvironment plays a decisive role for the induction of hepatic differentiation of rMSC.

Changes of the Microtubule Arrays During Mitosis in Prothallus Cells of Dryopteris crassirhizoma

Microtubule arrays in prothalli large-vacuolated and meristematic dividing cells of the fern Dryopteris crassirhizoma Nakai were studied using Steedman's wax, indirect immunofluorescence labelling and confocal laser scanning microscopy. Results showed that the use of high paraformaldehyde concentration (8%) allowed good fixation of prothallus cells, which are characterized by numerous (meristematic cells) and big (large-vacuolated cells) vacuoles. Results also plead for the efficiency of Steedman's wax embedding method in: (1) avoiding excessive use of enzyme for digesting cell wall in the process of the microtubule cytoskeleton labelling, (2) minimizing the autofluorescence effect in cells through utilization of alcohol in sample dehydration, and (3) permitting a clear visualization of microtubule patterns during the cell mitosis. Steedman's wax, coupled with immunofluorescence labelling and confocal laser scanning microscopy techniques, allows a good investigation of cell division process in plants by using simple multicellular organisms such as fern prothalli.

Cytoskeletal arrangement and its intercellular connection in wheat young leaf cells

By using the techniques of partial digestion of cell wall and selective extraction, we examined the cytoskeleton of wheat young leaf cells under scanning electron micro-scope(SEM). A 3-dimensional cytoskeletal system, showing some new features, was observed. The cortical network located beneath the cross wall was an anastomosing organization. The association of nucleus with the cell wall by some skeletal filaments was also found. It is noticeable that there were cytoskeletal filaments, which passed through cell wall and connected together with cytoskeletal arrays of adjacent cells. Thus, it is possible that an integral skeletal network existed within the young leaf tissue of wheat.

COMBINATION OF γ-INTERFERON WITH TRAIL AND CISPLATIN OR ETOPOSIDE INDUCES APOPTOSIS IN HUMAN NEUROBLASTOMA CELL LINE SH-SY5Y

Objective To study the effect of γ-interferon （IFNγ）, tumor necrosis factor related apoptosis inducing ligand （TRAIL）, and cisplatin or etoposide induced apoptosis in human neuroblastoma cell line SH-SY5Y and its possible molecular mechanisms. Methods The expressions of Caspase 8 mRNA and protein were detected with RT-PCR and Western blot analysis. The effects of IFNγ, TRAIL, IFNγ ＋ TRAIL, IFNγ ＋ Caspase 8 inhibitor ＋ TRAIL, IFNγ ＋ cisplatin ＋ TRAIL, and IFNγ ＋ etoposide ＋ TRAIL on the growth and apoptosis of SH-SY5Y cells were detected with the methods of MTT and flow cytometry. The relative Caspase 8 activity was measured with colorimetric assay. Results Caspase 8 was undetectable in SH-SY5Y cells but an increased expression of Caspase 8 mRNA and protein was found after treatment with IFNγ. SH-SY5Y ceils themselves were not sensitive to TRAIL, but those expressing Caspase 8 after treatment with IFNγ were. The killing effect of TRAIL on SH-SY5Y cells expressing Caspase 8 was depressed by Caspase 8 inhibitor. Cisplatin and etoposide could enhance the sensitivity of TRAIL on SH-SY5Y cells. The relative Caspase 8 activity of SH-SY5Y cells in IFNγ ＋ TRAIL group was significantly higher than those of control group, IFNγ group, TRAIL group, and inhibitor group （ P 〈 0. 01 ）. There was no significant difference among IFNγ ＋ TRAIL group, IFNγ ＋ cisplatin ＋ TRAIL group, and IFNγ ＋ etoposide ＋ TRAIL group. Conclusions IFNγ could sensitize SH-SY5Y cells to TRAIL-induced apoptosis and this may be realized by the up-regulation of Caspase 8. Cisplatin and etoposide could enhance the killing effect of TRAIL on SH-SY5Y cells.

Autologous serum can induce mesenchymal stem cells into hepatocyte-like cells

Objective： To investigate whether the rabbit serum after radiofrequency ablation to liver tumor can induce mesenchymal stem cells （MSCs） differentiating into hepatocyte-like cells in order to find a new source and culture process for repairing liver injury. Methods： A tumor piece of 1 mm× 1mm×1 mm was transplanted into a tunnel at right liver of rabbits. The model of liver tumor was established after 2-3 weeks. The serum was collected from rabbits 72 h after being subjected to radiofrequency ablation of the liver tumor. Mesenchymal stem cells were isolated from rabbit bone marrow and cultured in DMEM containing autologous rabbit serum. Three kinds of media （L-DMEM） were tested respectively： ① containing 10% fetal calf serum （FCS）; ② containing 30% rabbit autologous serum after radiofrequency ablation of the liver tumor （ASRF）; ③ containing 30% rabbit autologous serum （AS）. MSCs were cultured on 12-well plates until passage 2 and examined under the light and electron microscopy at indicted intervals. The expression of albumin and CKl8 was detected using immunofluorescence to identify the characteristics of differentiated cells. Results： MSCs performed differently in the presence of fetal calf serum, rabbit autologous serum and rabbit autologous serum after radiofrequency ablation of the liver tumor. Induced by the serum after radiofrequency ablation to liver tumor for 7 d, the spindle-shaped MSCs turned into round shaped and resembled hepatocyte-like cells. The reactions were not found in MSCs cultured in FCS and AS groups. After induction for 14 d, slender microvilli, cell-cell junction structure and cholangiole emerged, and the differentiated cells expressed albumin and CKl 8. All those could not been observed in 10% FCS and 30% autologous serum groups. Conclusion： Mesenchymal stem cells differentiate into hepatocyte-like cells in the serum after radiofrequency ablation of liver tumor, providing us a potential cell source and culture process for clinical application in liver injury repairing.