ESE-3 transcription factor and tumorigenesis / 基础医学与临床

ESE-3 belongs to the epithelium-specific ETS transcription factor subfamily of ETS (E26) located in chromosome 11p12. It belongs to the transcriptional regulation factor which forms transcription complexes with its effector molecules, enhancing or inhibiting transcription of different downstream target genes. The expression of ESE-3 is abnormal in many kinds of tumors, such as colon cancer, pancreatic cancer, prostate cancer, breast cancer and so on. It suggests that ESE-3 plays an important role on the pathogenesis of various tumors.

Adipogenic potentials of mesenchymal stem cells from human bone marrow, umbilical cord and adipose tissue are different / 中国实验血液学杂志

Mesenchymal stem cells (MSCs) could be obtained from many sources, and there are differences between them. This study was purposed to compare and analyze the basic biological characteristics of umbilical cord, adipose tissue-and bone marrow-derived MSC (UC-MSCs, AD-MSCs and BM-MSCs). The MSCs were isolated from umbilical cord, adipose tissue and bone marrow were cultured; the morphology of UC-MSCs, AD-MSCs and BM-MSCs was observed by using microscopy; the immunophenotype, differentiation potential and expression of peroxisome proliferation-activated receptor-γ (PPAR-γ) mRNA were detected by using flow cytometry, differentiation test (von kossais and 0:1 red O staining) and quantitative fluorescent PCR, respectively. The results showed that the UC-MSCs, AD-MSCs and BM-MSCs displayed similar morphology under confocal microscope after being stained with rhodamine phalloidin and DAPL. The immunophenotypes of these three originated cells conform to coincide with identification criterion for MSCs, and showed similar expression level. During adipogenic induction the adipogenic potential of these MSCs was different, AD-MSCs exhibited the highest adipogenic potential, UC-MSCs displayed the lowest, while potential of BM-MSCs get between; however, the osteogenic differentiation potential of UC-MSCs, AD-MSCs and BM-MSCs was similar. The PCR detection showed that the expression level of PPAR-γ mRNA was the highest in AD-MSCs and the lowest in UC-MSCs, while expression level in BM-MSCs get between, these results were identical with the adipogenic potential, suggest that the difference of adipogenic potential in 3 kinds of MSCs was associated with basic expression level of PPAR-γ mRNA. It is concluded that UC-MSCs, AD-MSCs and BM-MSCs exhibit similar morphology, the immunophenotypes of these MSCs coincide with identification criterion for MSCs, the osteogenic potential of these MSCs is similar, while the adipogenic potential and the expression level of PPAR-γ mRNA are different. The difference-associated mechanisms need to further study.

IL-1β promotes the hematopoietic support of human umbilical cord mesenchymal stem cells / 中国实验血液学杂志

This study was aimed to investigate the effect of IL-1β on hematopoietic support of human umbilical cord mesenchymal stem cells (hUC-MSC). 2×10(6) hUC-MSC were seeded in 75 cm(2) flasks, after adherence to wall for 2 h, 10 ng/ml IL-1β was added in hUC-MSC supernatant and cultured for 36 h, then the culture supernatants and cells were harvested. The effect of conditioned medium with/without IL-1β on CD34(+) cell hematopoietic support was observed, mRNA expression changes of hUC-MSC cultured in medium with/without IL-1β were monitored by real time PCR, the differences in hematopoiesis-related factors were detected by ELISA. The results showed that the conditioned culture medium of hUC-MSC with IL-1β enhanced the ability to form colony of CD34(+) cells, especially CFU-G and CFU-GM in vitro; IL-1β promoted the mRNA expression of GM-CSF, G-CSF, IL-6 on MSC; IL-1β also promoted the secretion of GM-CSF, G-CSF, and IL-6 protein from hUC-MSC. It is concluded that IL-1β enhances hematopoietic support capacity especially, capability of MSC to myeloid differentiation.

Isolation and biological characteristics of mesenchymal stem cells derived from human placenta decidua basalis / 中国实验血液学杂志

Comparing to bone marrow mesenchymal stem cells (MSCs), placenta-derived MSCs have the advantages of adequate sources, low immunogenicity, little risk of viral contamination, and no ethical controversy, and thus possess a better prospect for clinical application. Placental tissue not only includes chorionic and amniotic, but also contains decidua basalis which locate in the maternal placenta surface. The biological characteristics of MSCs isolated from decidua basalis have not been well studied. This study was aimed to investigate the biologic characteristics of placenta decidua basalis-derived MSC from placenta decidua basalis (DB) by enzymatic digestion. Short tandem repeats (STR) test was used to identify the cells derived from the maternal placenta surface. Growth rate of decidua basalis mesenchymal stem cells (DB-MSC) was measured by MTT. Cell cycle and cell phenotype were detected by flow cytometry. Inducing differentiation was used to evaluate multipotency of DB-MSC. For testing the immunosuppression of DB-MSC, they were co-cultured with peripheral blood mononuclear cells (PBMNC) stimulated by phytohemagglutinin (PHA) and then IFN-γ in the co-cultured media was quantified by ELISA. The results showed that the cells were derived from the maternal placenta by STR analysis. DB-MSC showed typical fibroblast morphology in the culture and were positive for the MSC surface markers: CD90, CD73, CD105, CD44 and negative for CD45, CD11b, and CD34. DB-MSC underwent osteogenic, adipogenic and chondrogenic differentiation in inducing medium. DB-MSC could inhibit the secretion of IFN-γ by PBMNC. It is concluded that the cells are isolated from placenta decidua basalis and possess the basic characteristics of MSC. DB-MSC can be an important maternal autologous MSC and may be a safe and effective treatment for immune system diseases, which makes the DB-MSC as an important source of autologous MSC from mother. DB-MSC can be safely for the treatment of the mother's immune system diseases.

Long term in-vitro expansion reduces immune modulation function of placental chorionic villi mesenchymal stem cells / 中国实验血液学杂志

The main aim of this study was to investigate the biological activities and immune modulation changes of chorionic villi mesenchymal stem cells (CV-MSC) after long term culture. The morphology of the CV-MSC of passage 3 and passage 9 were observed by microscopy, and their phenotypes were detected by flow cytometry. CV-MSC of passage 3 and 9 were co-cultured with PHA-stimulated PBMNC, and IFN-γ concentration in culture medium was detected by ELISA. The mRNA expression of COX-2, HGF and HLA-G in CV-MSC were detected by real-time PCR. The results showed that after long term culture, the CV-MSC kept the MSC morphology and most of the phenotypes including CD31, CD34, CD44, CD45, CD62L, CD73, CD90, CD105, CD117, CD151, CD235a, CD271 and HLA-DR, while the CD49d was significantly up-regulated. Immune modulation ability of CV-MSC was reduced and the mRNA expression of COX-2 and HGF was down regulated after long term culture, but the expression of HLA-G did not found to be obvious change. It is concluded that the long term in vitro expansion changes the expression of CD49d and reduces immune modulation of CV-MSC.

Effect of 15-deoxy-Δ(12), 14-prostaglandin J2 on the cytokines in the culture supernatant of bone marrow mesenchymal stem cells / 中国实验血液学杂志

15-Deoxy-Δ(12), 14-prostaglandin J2 (15d-PGJ2), a well known peroxisome proliferator activated receptor (PPAR) γ ligand, has been shown to inhibit cellular proliferation and induce apoptosis and differentiation. However, whether 15d-PGJ2 influences the cytokines in the culture supernatant of bone marrow mesenchymal stem cells (BM-MSC) is unknown. This study was purposed to investigate the influence of 15d-PGJ2 on cytokines in the culture supernatant of BM-MSC. The fibroblast-like cells attached to the culture dish from bone marrow of healthy donors were isolated. The immunophenotype and differentiation potential of the obtained cells were detected by flow cytometry and oil red O and von kassa staining respectively to confirm that these cells were BM-MSC. Thereafter, the BM-MSC were cultured with complete medium supplemented with 10, 20, 40 and 60 µmol/L 15d-PGJ2 for 24 hours respectively. The real-time PCR was used to assay the PPARγ mRNA level, the confocal immuno fluorescence technique was used to detect the expression level of PPARγ. The results showed that the BM-MSC underwent apoptosis and got detached from the culture dish when the concentration of 15d-PGJ2 was no less than 20 µmol/L. The PPARγ mRNA level of BM-MSCs cultured with medium containing 10 µmol/L 15d-PGJ2 was higher than that cultured without 15d-PGJ2, and the difference was statistically significant (P < 0.05). The enhancement of PPARγ expression was observed after stimulated by 15d-PGJ2. The protein chip detecting the culture supernatants of BM-MSC cultured with 10 µmol/L 15d-PGJ2 or without 15d-PGJ2 for 24 hours demonstrated that expression levels of some of the cytokines varied. It is concluded that the down-regulation of TIMP-2 exists after treatment of 15d-PGJ2, which is statistical significant.

Supportive effects of conditioned culture media of human umbilical cord mesenchymal stem cells on hematopoiesis in vitro / 中国实验血液学杂志

This study was aimed to explore whether the conditioned culture medium of human umbilical cord-derived mesenchymal stem cells (hUC-MSC) has supportive effects on hematopoiesis in vitro. hUC-MSC were cultured in 75 cm(2) culture flasks at a concentration of 2×10(6) cells per flask. After 48 h, the conditioned culture medium was harvested. CD34(+) cells were isolated with the human cord blood CD34 positive selection kit. The CD34(+) cells were plated in three different culture systems: the culture supernatant from hUC-MSC added into incomplete methylcellulose without recombinant human cytokines as conditioned culture medium; the complete methylcellulose medium with recombinant human cytokines as positive control medium; incomplete methylcellulose adding DMEM/F12 with 10% FBS instead of conditioned culture medium as the negative control medium. After 14 days of culture, colonies containing ≥ 50 cells were scored and types of colonies were classified under inverted microscope. The immunophenotypes of cells which were collected from the colonies were detected by flow cytometry. The results showed that conditioned culture medium of hUC-MSC supported the differentiation of CD34(+) cells into CFU-G (47.67 ± 0.58), CFU-GM (48.67 ± 4.73) and CFU-M (3.00 ± 2.00) in vitro, while the CFU-E, BFU-E or CFU-GEMM were absent. Comparatively, in the positive control medium all kinds of CFU were observed. Interestingly, the percentage of CD45(+)cells of CFU in conditioned culture medium (97.43 ± 2.15)% was more than CD45(+)cells in positive control medium (39.69 ± 0.96)% (P < 0.05). It is concluded that the conditioned culture medium of hUC-MSC has been confirmed to have ability to support hematopoiesis separately in vitro. Besides, it enhances the differentiation of CD34(+) cells into myeloid cells except cells of erythroid lineage.

Comparative study of biological characteristics of human umbilical cord and placental chorionic villous mesenchymal stem cells / 中国实验血液学杂志

Because advantage of tissue origin and proliferation potential, the umbilical cord-derived mesenchymal stem cells (UC-MSC) and placental chorionic villous-derived mesenchymal stem cells (CV-MSC) have clinical application potential, as compared with bone marrow MSC. But whether the differences of biological characteristics exist between UC-MSC and CV-MSC, which deserve to be further explored. This study was purposed to compare the biological characteristics of UC-MSC and CV-MSC. The placental and umbilical cord were cleaned by using the sterile physiological salt, the UC-MSC and CV-MSC were separated by enzyme digestion. Short tandem repeat (STR) analysis was used to detect whether the MSC obtained from fetal tissue. MTT method was used to detect proliferation of MSC. Flow cytometry was applied to analyze cell phenotype. The different differential medium was used to detect their multi-directional differentiation capacity. After the MSC and PHA-stimulated peripheral blood mononuclear cells were co-cultured, the γ-interferon (IFN-γ) levels of the co-culture supernatant were detected using the ELISA. The results showed that these MSC were derived from fetal tissue by STR analysis. They were adherent cells with typical fibroblast morphology. Cells expressed the MSC surface markers CD90, CD73 and CD105 and CD44, not expressed CD45 and of CD11b and CD34.These cells could differentiate into osteoblasts and adipoblasts under culture with different conditioned medium, but in the adipogenic differentiation of CV-MSC, the larger lipid droplets appeared. It is concluded that these cells are obtained MSC. These MSC can inhibit peripheral blood mononuclear cells stimulated by PHA to secrete IFN-γ, and the the CV-MSC have a stronger suppression capacity, which makes the CV-MSC to have a greater advantage in the treatment of autoimmune diseases.

Umbilical cord mesenchymal stem cell transplantation for treatment of experimental autoimmune myasthenia gravis in rats / 中国实验血液学杂志

Umbilical cord mesenchymal stem cell (UCMSC) transplantation has been widely used in the treatment of a variety of diseases due to their advantages such as abundant resources, low immunogenicity and large ex vivo expansion capacity. This study was aimed to investigate the effects of UCMSC on experimental autoimmune myasthenia gravis (EAMG) rats. The distribution of human-derived cells was observed by immunofluorescence method, the effect of MSC on B-cell in situ-secreted antibodies was assayed by ELISPOT, the secreted IFN-γ level was detected by using Transwell test. The results showed that UCMSC were able to migrate to inflammation region and lymph nudes, moreover human-derived cells could be detected in medulla zone of lymph nudes. In vitro in situ detection of AchR specific antibody secretion revealed that the full contact of MSC with lymphnode-derived lymphocytes could effectively inhibit production of AchR antibody. Transwell test indicated that the direct contact of UCMSC with CD4 T cells could effectively decrease production of IFN-γ, which modulated the unbalance between Th1/Th2 to a certain extent. It is concluded that UCMSC can regulate the immune system by direct cell-cell contact or/and release of cytokines, which bring a new insight into knowledge about MSC-based therapy for EAMG.

Reversal of leukemia multidrug resistance by sequence-specific short hairpin RNA / 中国实验血液学杂志

This study was aimed to design and screen short hairpin RNA (shRNA) molecules targeting multidrug resistance gene (mdr1), as well as to investigate the effects of shRNA expression vector on K562/A02 cells. Mdr1-shRNA expression vector was transfected into K562/A02 cells by lipofectamine 2000, and G418 was added to screen and establish the stable expression cell strain. The expressions of mdr1 mRNA and protein were detected by real-time RT-PCR and Western blot respectively. The sensitivity of cells to chemodrugs after interference were tested by CCK8 assay. The function of p-glycoprotein was determined by Rhodamine 123 efflux experiment. The results showed that all of 4 mdr1-shRNA expression vectors could significantly knockdown the expression of p-glycoprotein as compared with control vector, moreover, the vector targeting 508 - 526 sites of mdr1 gene was the best one. It is concluded that the mdr1-shRNA expression vector gained by screening can significantly knockdown the expression of mdr1 gene and reverse leukemia drug resistance, paving the way for the application of RNAi in the following animal experiments.

Role of antiapoptotic Bcl-X(L) in megakaryocyte differentiation and maturation / 中国医学科学院学报

<p><b>OBJECTIVE</b>To investigate the role of antiapoptotic Bcl-x(L) protein in megakaryocyte differentiation and maturation.</p><p><b>METHODS</b>RNA interference was used to block the expression of Bcl-x(L) when K562 cells were induced to differentiate into megakaryocyte (CD61 + cells) by PDBu, and the expression of Bcl-x(L) was evaluated with flow cytometry and reverse transcription polymerase chain reaction (RT-PCR). The CD34 + cell fraction was positively isolated by using the MiniMACS system from normal bone marrow. Immunochemical staining and flow cytometry were used to detect the expression of Bcl-x(L) in the differentiation (CD41 + cells) of CD34 + cells induced by trombopoietin (TPO).</p><p><b>RESULTS</b>Among K562 cells induced by PDBu, the percentage of CD6L + cells rapidly increased in 24 hours and maintained at a high positive level in 72 hours. When exposured to si-Bcl-x(L), the percentage of CD6 1 + cells only slightly increased in 72 hours. The expression of Bcl-x(L) mRNA was significantly decreased after transfection compared with that of control group, and Bcl-x(L) protein expression decreased correspondingly. After the CD34 + bone marrow cells having been treated with TPO for 5 days to 20 days, the Bcl-x(L)-megakaryocytes increased as the culture time prolonged, and there was a strong expression of Bcl-x(L) in immature megakaryocyte and an obviously decreased expression in degenerating megakaryocytes maturation.</p><p><b>CONCLUSIONS</b>Increased expression of antiapoptotic Bcl-x(L) may be essential to mature megakaryocyte. The down-regulation of antiapoptotic Bcl-x(L) in mature megakaryocyte may be crucial to platelets formation.</p>

Effect of silencing hypoxia-inducible factor-1 alpha by RNA interference on human breast carcinoma cell line / 中国医学科学院学报

<p><b>OBJECTIVE</b>To investigate the effect of short hairpin RNA (shRNA) targeting hypoxia-inducible factor-1 alpha (HIF-1 alpha) on the human breast carcinoma MCF-7 cell line.</p><p><b>METHODS</b>The hypoxia environment was achieved by treating cells with cobalt chloride. The shRNA eukaryotic expression vector targeting HIF-1 alpha was constructed, and transfected into MCF-7 cells through lipofectamine 2000. Semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR) was used to study the expression of vascular endothelial growth factor (VEGF). The mRNA and protein level of HIF-1 alpha were detected by real-time PCR and Western blot. Sub-G1 apoptotic population analysis, Annexin V/PI binding assay, and DNA ladder analysis were applied to investigate the cell apoptosis. The cell cycle was detected by flow cytometry.</p><p><b>RESULTS</b>The mRNA and protein level of HIF-1 alpha increased after exposure of MCF-7 cells to hypoxia (P < 0.01). However, apoptosis was lower in hypoxia compared with normoxia (P < 0.05). The HIF-1 level of MCF-7 transfected with HIF-1 alpha shRNA decreased approximately 91.63% (P < 0.01). When the cells were treated with or without apoptosis inducer Ara-C, the apoptosis of MCF-7 cells transfected with HIF-1 alpha shRNA increased by 1.75 times (P < 0.01) and 61. 31 times (P < 0.01), respectively. The expression of VEGF in MCF-7 cells transfected with HIF-1 alpha shRNA decreased 66.8% compared with untransfected cells (P < 0.05). Cell cycle progression was inhibited when the MCF-7 cells were transfected with HIF-1 alpha shRNA.</p><p><b>CONCLUSIONS</b>HIF-1 alpha plays an anti-apoptotic role in human breast carcinoma MCF-7 cell line. The shRNA we designed targeting HIF-1 alpha in MCF-7 can promote cell apoptosis, inhibit the expression of VEGF, and delay cell cycle progression.</p>

High expression of mirobial transglutaminase gene from Streptoverticillium mobaraense in Escherichia coli / 生物工程学报

The microbial transglutamunase (MTG) gene was amplified from the genomic DNA of Streptoverticillium mobaraensea by using PCR and inserted into pET vector to construct the expression plasmid called pET-MTG. The pET-MTG was transfected into E. coli (Rosetta DE3) and the MTG protein was found to be highly expressed as inclusion bodies. The inclusion bodies were isolated and subjected to denaturation and re-naturation, followed by strong cation ion-exchange chromatography to purify the expressed MTG. The specific activity of purified MTG was close to that of native MTG. Taken together, this study might provide a base for the industrial production of microbial transglutaminase.