【Abstract】 Objective To investigate the biocharacteristics of c-kit+ human amniotic fluid-derived mesenchymal stemcells (HAFMSCs) and its capacity to differentiate into cardiomyocytes in vitro. Methods Fifty samples of human amnioticfluid were obtained from amniocenteses or voluntary termination of pregnancy and were expanded in vitro. c-kit+ HAFMSCs were sorted by flow cytometry and were recultured in the same media. c-kit+ HAFMSCs were amplified and identified, then exposed to osteogenic , adi pogenic, and myogenic media. The flow cytometry, and immunocytochemistry were used for identifying the cell phenotype, von Kossa staining for osteogenic differentiation, oil red O staining for adi pogenic differentiation, and real-time fluorescent quantitative PCR for the expressions of NKx2.5, Tbx5, GATA-4, and α-MHC genes. Results After the selection procedure, the percentage of c-kit+ HAFMSCs was 3.07% ± 1.03% of the total adherent cells. The cells expressed MSCs markers (CD29, CD44, CD73, CD90, CD105), and did not express hematopoietic stem cells markers (CD34, CD45). The cells were positive for human leukocyte antigen (HLA)-ABC, and negative for HLA-DR. They also expressed Oct-4, which characterized the undifferentiated stem cell state. The growth curves of c-kit+ HAMFSCs at passages 5, 10, and 15 were similar. Li pid droplet was observed by oil red O staining and calcium deposition by von Kossa staining in the cells at 21 days after adi pogenic and osteogenic induction. The myocardium special gene expressions of Tbx5, Nkx2.5, GATA-4, and α-MHC were significantly ber after myogenic induction than those before myogenic induction (P lt; 0.05). Conclusion Selected c-kit+ HAFMSCs by flow cytometry is a group of pure MSCs, which has potential to differentiate into cardiomyocytes and can be used as seeding cells for myocardium regeneration treatment.
Objective To investigate the expression of c-kit in human intermediate-spl it-thickness skin grafts and normal skin, and to recognize the role of c-kit in hyperpigmented process of the skin grafts. Methods The hyperpigmented intermediate-spl it-thickness skin grafts of 16 patients’ face and cervicum 1 year after operation was harvested and the normal skins around the recipient site and the donor site were used as controls. Envision immunohistochemical technique was usedto detect the expression and distribution of c-kit in the skin grafts and in the normal control skins, respectively. Medical image quantitative analysis system was used to quantitate the positive expression index (PI). Results The expression of c-kit was located in endochylema and cytolemma of melanocytes and keratinocytes in the basilar part of epidermis. The positive expression of c-kit was obvious in the intermediate-spl it-thickness skin grafts and blown zone was observed in the basilar part of epidermis; and was not obvious and local in normal control skins. The PI of c-kit in the intermediate-spl it-thickness skin grafts (131 216 ± 19 130) was significantly higher than that in the normal skin around the recipient site (92 958 ± 16 208) and in the normal skin around the donor site (91 306 ± 8 135); showing statistically significant difference (P lt; 0.05). Conclusion The expression of c-kit in intermediate-spl it-thickness skin grafts increases remarkably compared with that in normal control skin. c-kit may play an important adjusting role in the process of hyperpigmentation of skin grafts．
Objective To discuss the changes of c-kit/scf mRNA and protein in guinea pig gallbladder fed on high cholesterol diet. Methods Twenty guinea pigs were divided into two equal groups of 10 each：the control group and lithogenic group. Normal diet and high cholesterol diet was given to each group respectively. The period of stone permeation was six weeks. RT-PCR and Western blot were used to determin the expressions of c-kit and scf mRNA and protein. Results RT-PCR results showed that the expressions of c-kit mRNA（t=6.985，P＜0.01） and scf mRNA （t=6.028， P＜0.01）decreased significantly in lithogenic group compared with the control group. Western blot results showed that the expressions of c-kit protein （t=10.256， P＜0.01） and scf protein （t=9.586， P＜0.01）decreased significantly in lithogenic group compared with the control group. Conclusions The expressions of c-kit/scf mRNA and protein decrease during the formation of cholesterol gallstones in guinea pigs fed on high cholesterol diet. Inhibition of c-kit/scf pathway may play a role in the formation of cholesterol gallstones.
ObjectiveTo summarize the pathogenesis and epidemiology features of gastrointestinal stromal tumor(GIST), explore its diagnosis and therapy, and analyze its prognosis. MethodThe pertinent literatures about the pathogenesis, epidemiology features, diagnosis, therapy, and prognosis of GIST in recent years were reviewed. ResultsGIST was non-epithelial tumor which derived from interstitial cells of Cajal, was the most common mesenchymal tumor about accounting for 1%-3% in the digestive tract tumor. The median onset age of patients with GIST was 40-60 years. The gastric stromal tumor was about 60% in all the digestive tract tumor. The current consensus statement was that there was a relation between the pathogenesis of the GIST and proto-oncogene c-kit or platelet-derived growth factor receptor alpha(PDGFRα)gene mutation. But the mutations of PDGFRαand c-kit gene did not emerge at the same time in the same patient. The clinical manifestations of GIST were not specific, and the diagnosis mainly depended on endoscope and image technology, the correct diagnosis depended on pathological examination. The treatment of GIST was given priority of surgery and molecular targeted drug therapy, and the prognosis was closely related to risk assessment stratify of GIST. ConclusionsGISTs are mesenchymal tumors that has a potential of malignant transformation, the risk classification criteria for aggressive clinical course of primary GIST is an important indication for guiding the clinical therapy and prognostic evaluation. Further research would be needed in prevention, diagnosis, treatment, and relapse prevention of GIST.