Objective To investigate effect on telomerase activity, apoptosis and p53/bcl-2 gene expression of MCF-7 cells line induced by paclitaxel.Methods By techniques of cell culture in vitro, telomeric repeat amplification protocol with ELISA(TRAP-ELISA) and flow-cytometry (FCM), MCF-7 cell line was treated by paclitaxel in various concentration for 72h.Results Paclitaxel down-regulated telomerase activity of MCF-7 cell, induced apoptosis of the cell in a concentration-dependent manner, significantly decreased expression of bcl-2 gene protein and increased expression of p53 gene protein. There was a positive correlation between telomerase activity and apoptosis and the expression of p53/bcl-2 gene protein.ConclusionPaclitaxel could down-regulate telomerase activity,induce apoptosis, decrease expression of bcl-2 gene protein and increase expression of p53 gene protein, which may be one of important mechanisms of Paclitaxel′s anticancer action.

Objective To investigate effect on telomerase activity of Hep-2 cells treated by anticancer drugs(hydroxycamptothecine, cisplatin and cytoxan).Methods By MTT method,we measured the 50% inhibitory concentration(IC 50 ) at 72h,and compared to untreated control cells. Telomerase activity of Hep-2 cells treated by the drugs in different concentration based on IC 50 for different time was observed by Telomeric Repeat Amplification Protocol with ELISA(TRAP-ELISA).Results Hydroxycamptothecine and cytoxan could inhibit proliferation of Hep-2 and down-regulate telomerase activity of Hep-2 cell. However, cisplatin promoted proliferation of Hep-2 and up-regulated telomerase activity of Hep-2 cell.Conclusions Hydroxycamptothecine and cytoxan could down-regulate telomerase activity of Hep-2 cell by direct or indirect pattern, which may correlate with drug concentration and time-dependent pattern.Cisplatin could up-regulate telomerase activity of Hep-2 cell, which mechanism is not clear.

The culture of umbilical cord-derived mesenchymal stem cells is extremely important for studies on umbilical cord mesenchymal stem cells. Optimization of cellculture technology is crucial for clinical application of mesenchymal stem cells and even celltherapy. Meanwhile, the labeling and tracer technique of umbilical cord-derived mesenchymal stem cells is a hotspot in stem celltransplantation. OBJECTIVE:To review the research and development of the cellmarkers and tracer methods of umbilical cord-derived mesenchymal stem cells. METHODS:A computer-based search of VIP, CNKI, Medline, Highwire and Foreign Journals Integration System databases was performed for articles concerning culture and labeling of umbilical cord-derived mesenchymal stem cells published from January 2001 to October 2013. The keywords were“stem cells, mesenchymal stem cells, umbilical cord-derived mesenchymalstem cells, cellculture, labeling methods”in Chinese and English, respectively. Final y, 35 articles were included in result analysis. RESULTS AND CONCLUSION:Umbilical cord-derived mesenchymal stem cells have not yet been widely used, mainly because of the immature isolation, culture and staining techniques of umbilical cord-derived mesenchymal stem cells. These techniques are worthy of further optimization studies. Although in recent years, cellmarkers and tracer technology of umbilical cord-derived mesenchymal stem cell s have made great progress, there are stil many problems need to be solved.

BACKGROUND: Antiviral drugs can reduce the incidence of early-onset cytomegalovirus(CMV)disease,but are associated with strong toxicity and the development of late-onset CMV disease.In order to prevent CMV disease better,cytotoxic T lymphocytes(CTL)may play a critical role in controlling CMV reactivation.Fluorescent HLA-peptide tetramers are used to monitor the recovery of CMV CTL in recipients of allogeneic transplants.OBJECTIVE: To explore the effect of HLA-peptide tetramers and adoptive immunotherapy in treating CMV disease.METHODS: A computer-based online search of Pubmed and Wanfang databases was performed for articles related to CTL detection,application of antiviral drugs and HLA-peptide tetramers,and adoptive immunotherapy with key words"HLA-peptide tetramers,cytomegalovirus,specific CTL,adoptive immunotherapy"in English and Chinese.Repetitive articles were excluded and 29 articles were included.RESULTS AND CONCLUSION: Adoptive immunotherapy with CMVs cytotoxic T cells as preemptive therapy is a very elegant strategy; however,generation of these cells is costly and time-consuming,and therefore the therapy is not available at every transplantation center.Magnetic selection of CMVs CD8+T cells from peripheral blood of CMV-seropositive donors by using HLA-peptide tetramers may be very hopeful,which simplifies adoptive immunotherapy.

Objective To study the alteration of telomerase activity of MCF 7 cell line of breast cancer in the presence of different anticancer drugs. Methods The hyperplasia and viability of MCF 7 cell were detected by cell counting and trypan blue exclusion, and the telomerase activity was measured by TRAP.The alteration of MCF 7 cell and its related factors of telomerase activity were observed on cell growing in different condition. Results In abscence of drug, there was a positive correlation between hyperplasia and telomerase activity of the cell(r= 0.901 ). Adriamycin, paclitaxel and cisplatin could obviously inhibit the growth and reduce the telomerase activity of the cell in a dose-dependent and time-dependent fashion, and this reduction in telomerase activity closely correlated with the reduction in the number of viable cells. Conclusions Adriamycin, paclitaxel and cisplatin can inhibit the growth of MCF 7 cell, which may be correlated with the reduction in telomerase activity and cell viability.

BACKGROUND:If an extract can prolong the S phase and reduce the percentage of apoptosis after co-culture with cels, it is proved that the extract is able to promote cel proliferation. OBJECTIVE: To prove the effects of chicken egg-white extracts with different components on the proliferation, cel cycle and apoptosis of 293T cels. METHODS: An ultrafiltration unit was used to separate chicken egg-white extracts into different components that were > 10 ku, < 10 ku, > 3 ku and < 3 ku to co-culture with cels for 3 days. Then, cel proliferation, cel cycle and cel apoptosis were detected. RESULTS AND CONCLUSION:Chicken egg-white extract components of < 10 ku and < 3 ku could promote cel proliferation, increase the percentage of S-phase cels and reduce the percentage of apoptosis. In conclusion, chicken egg-white extract components that are < 10 ku and < 3 ku can promote cel proliferation, as wel as increase the percentage of S-phase cels and reduce apoptosis percentage.

BACKGROUND:There are less studies addressing whether bone marrow mesenchymal stem cells from systemic lupus erythematosus patients are different from healthy people.
OBJECTIVE:To compare the multi-differentiation capacity of bone marrow mesenchymal stem cells isolated from systemic lupus erythematosus model mice and normal control mice.
METHODS:Bone marrow mesenchymal stem cells of systemic lupus erythematosus model mice and C57BL mice were isolated and cultured fol owed by osteogenic and adipogenic differentiations, respectively. Differentiation abilities of two kinds of mouse bone marrow mesenchymal stem cells were observed.
RESULTS AND CONCLUSION:Passaged bone marrow mesenchymal stem cells from C57BL mice were long spindle-shaped and evenly distributed, while bone marrow mesenchymal stem cells from systemic lupus erythematosus model mice showed slow growth and were relatively smal er than those from C57BL mice. After osteogenic induction, the amount of calcium salt and calcium nodules were significantly less in the bone marrow mesenchymal stem cells from systemic lupus erythematosus model mice than from normal control mice. PCR detection showed that expressions of Runx2, alkaline phosphatase and osteocalcin were also significantly decreased in the bone marrow mesenchymal stem cells from systemic lupus erythematosus model mice. After adipogenic induction, the number of lipid droplets in the bone marrow mesenchymal stem cells from systemic lupus erythematosus model mice was significantly less than the control group, and PCR detection also showed significantly decreased expression of adipogenic genes, including PPARγ2 and lipoprotein lipase. These findings suggest that the bone marrow mesenchymal stem cells from systemic lupus erythematosus model mice exhibit lower osteogenic and adipogenic capacities than those from normal C57BL mice, and also have the impaired multi-differentiation ability.

Objective To establish a method for isolation of cynomolgus monkey umbilical cord mesenchymal stem cells.Methods Fresh cynomolgus monkey umbilical cord was directly minced into pasty fine pieces, and the pieces were cultured in tissue flask with DMEM/F12 medium supplemented with 10% fetal bovine serum.The morphological characteristics of the resulting cells were examined, and their expression of mesenchymal cell surface markers were analyzed by flow cytometry.The multidifferentiation potential was examined in vitro, too.Results The fibroblast-like cells were successfully isolated from the fresh umbilical cord by an adherent culture procedure.These adherent cells expressed mesenchymal markers including CD29, CD44, and CD90, and also could be induced to differentiate into adipocytes, osteoblasts and chondrocytes.Conclusion Mesenchymal stem cells can be isolated from fresh cynomolgus monkey umbilical cord by using an adherent culture procedure.

BACKGROUND:Umbilical cord as childbirth waste has wide variety of sources and can be easily obtained, without any ethical and legal restrictions. Therefore, human umbilical cord mesenchymal stem cells break al the restrictions originated from other sources of mesenchymal stem cells. OBJECTIVE:To review the application of human umbilical cord mesenchymal stem cells in cartilage diseases, neuroglioma, ischemic brain injury, lung disease, liver disease and models of myocardial infarction. METHODS:The PubMed and Wanfang databases were searched by the first author using the keywords of“human umbilical cord mesenchymal stem cells, disease models, celltherapy”in English and Chinese, respectively. Seventy-three articles were searched and final y, 35 articles were included in result analysis. RESULTS AND CONCLUSION:Human umbilical cord mesenchymal stem cells have multilineage differentiation capacity similar to bone marrow mesenchymal stem cells. Compared with bone marrow mesenchymal stem cells, human umbilical cord mesenchymal stem cells have lower immunogenicity. Human umbilical cord mesenchymal stem cells show certain curative effects on cartilage disease, neuroglioma, ischemic brain injury, lung disease, liver disease and myocardial infarction, indicating that human umbilical cord mesenchymal stem cells can be used for celltransplantation to treat various diseases.

BACKGROUND: The inoculation of hybridoma cell strain onto mouse abdominal cavity may obtain ascites containing mass antibody. Previous method to purify monoclonal antibody in ascites is complex and difficult to operate.OBJECTIVE: To prepare, purify and label anti-human leukocyte antigen (HLA)-I class molecule light chain monoclonal antibody, and to detect the expression of tumor cell surface HLA-I class molecules. METHODS: Hybridoma cells were inoculated onto the mouse abdominal cavity. Ascites containing anti-human light chain beta2-microglobulin antibody were obtained and purified with the modified caprylic acid-ammonium sulfate method. The purified monoclonal antibody was labeled with fluorescein isothiocyanate to detect peripheral blood mononuclear cells, T2 cells expressing blank HLA-A2 molecule and K562 cells surface HLA-I class molecules. The expression of HLA-I class molecules was determined by using flow cytometry and fluorescent microscopy. RESULTS AND CONCLUSION: The purified anti-human light chain beta2-microglobulin-fluorescein isothiocyanate monoclonal antibodies accounted for 96% purity. Flow cytometry results showed that, the HLA-I class molecules were highly expressed in peripheral blood mononuclear cells surface, lowly expressed in T2 cells, and not expressed in K562 cells surface. It is a simple and convenient method to purify ascites with the modified caprylic acid-ammonium sulfate method, and according prepare anti-human light chain beta2-microglobulin-fluorescein isothiocyanate. This method is effective to distinguish the levels of HLA-I class molecules expressed in various cells.