Serum-Free Suspension Adaptation of HEK-293T Cells: Basis for Large-Scale Biopharmaceutical Production

Abstract Human Embryonic Kidney 293T cells (HEK-293T) are the most common host for viral vector production and are also widely employed for recombinant protein production. These cells are typically cultured in monolayer (adherent culture) using culture medium containing fetal bovine serum (FBS), which impairs batch-to-batch reproducibility and scale-up. The adaptation of adherent cell culture to suspension culture in chemically defined serum-free culture medium is an attractive approach for large-scale bioprocess implementation while aiming for a Good Manufacturing Practice (GMP) compliant production process. Therefore, in the present study, our goal was to adapt HEK-293T cells to serum-free suspension culture conditions and evaluate the feasibility of adapted cells to be transfected using different plasmid vectors for recombinant protein production. Firstly, the cells were efficiently adapted to serum-free conditions by sequential adaptation (FBS-containing medium weaning). During the whole process, parameters such as cell growth, viability and doubling time were evaluated and compared to the control (adherent serum-supplemented HEK-293T cell culture). Afterwards, these cells were adapted to suspension culture by using Erlenmeyer flasks in an orbital shaker platform, being able to achieve meaningful cell density with high viability. Adapted cells presented a transfection efficiency of approximately 50% for all vector constructs used (1054-GFP, Factor-VIII and Factor-IX). Overall, it was possible to successfully adapt HEK-293T cells to suspension and serum-free conditions, which represents an important step towards the development of a scalable and GMP-compliant production process. In addition, adapted cells efficiently expressed the different transgene tested, opening up possibilities for its use in recombinant protein production.

Smad1/5 signal transduction regulates the ameloblastic differentiation of induced pluripotent stem cells

Abstract Induced pluripotent stem (iPS) cells could be induced into ameloblast-like cells by ameloblasts serum-free conditioned medium (ASF-CM), and bone morphogenetic proteins (BMPs) might be essential during the regulation of this process. The present study investigates the signal transduction that regulates the ameloblastic differentiation of iPS cells induced by ASF-CM. Mouse iPS cells were characterized and then cultured for 14 days in epithelial cell medium (control) or ASF-CM. Bone morphogenetic protein receptor II (BMPR-II) siRNA, inhibitor of Smad1/5 phosphorylation activated by activin receptor-like kinase (ALK) receptors, and inhibitors of mitogen-activated protein kinases (MAPKs) phosphorylation were used to treat the iPS cells in combination with ASF-CM. Real-time PCR, western blotting, and immunofluorescent staining were used to evaluate the expressions of ameloblast markers ameloblastin, enamelin, and cytokeratin-14. BMPR-II gene and protein levels increased markedly in ASF-CM-treated iPS cells compared with the controls, while the mRNA levels of Bmpr-Ia and Bmpr-Ib were similar between the ASF-CM and control groups. ASF-CM stimulation significantly increased the gene and protein expression of ameloblastin, enamelin and cytokeratin-14, and phosphorylated SMAD1/5, p38 MAPK, and ERK1/2 MAPK compared with the controls. Knockdown of BMPR-II and inhibition of Smad1/5 phosphorylation both could significantly reverse the increased expression of ameloblastin, enamelin, and cytokeratin-14 induced by ASF-CM, while neither inhibition of p38 nor ERK1/2 phosphorylation had significant reversing effects. We conclude that smad1/5 signaling transduction, activated by ALK receptors, regulates the ameloblastic differentiation of iPS cells induced by ameloblast-conditioned medium.

Suspension culture of Vero cells for the production of adenovirus type 5

Smad1/5 signal transduction regulates the ameloblastic differentiation of induced pluripotent stem cells

Abstract Induced pluripotent stem (iPS) cells could be induced into ameloblast-like cells by ameloblasts serum-free conditioned medium (ASF-CM), and bone morphogenetic proteins (BMPs) might be essential during the regulation of this process. The present study investigates the signal transduction that regulates the ameloblastic differentiation of iPS cells induced by ASF-CM. Mouse iPS cells were characterized and then cultured for 14 days in epithelial cell medium (control) or ASF-CM. Bone morphogenetic protein receptor II (BMPR-II) siRNA, inhibitor of Smad1/5 phosphorylation activated by activin receptor-like kinase (ALK) receptors, and inhibitors of mitogen-activated protein kinases (MAPKs) phosphorylation were used to treat the iPS cells in combination with ASF-CM. Real-time PCR, western blotting, and immunofluorescent staining were used to evaluate the expressions of ameloblast markers ameloblastin, enamelin, and cytokeratin-14. BMPR-II gene and protein levels increased markedly in ASF-CM-treated iPS cells compared with the controls, while the mRNA levels of Bmpr-Ia and Bmpr-Ib were similar between the ASF-CM and control groups. ASF-CM stimulation significantly increased the gene and protein expression of ameloblastin, enamelin and cytokeratin-14, and phosphorylated SMAD1/5, p38 MAPK, and ERK1/2 MAPK compared with the controls. Knockdown of BMPR-II and inhibition of Smad1/5 phosphorylation both could significantly reverse the increased expression of ameloblastin, enamelin, and cytokeratin-14 induced by ASF-CM, while neither inhibition of p38 nor ERK1/2 phosphorylation had significant reversing effects. We conclude that smad1/5 signaling transduction, activated by ALK receptors, regulates the ameloblastic differentiation of iPS cells induced by ameloblast-conditioned medium.

Comparison of Effect of Serum-Free Culture Systems on Directional Erythroid Differentiation of Human Umbilical Cord Blood CD34 Cells / 中国实验血液学杂志

OBJECTIVE@#To compare the efficacy of directional erythroid differentiation in different serum free culture systems and to screen the optimal culture systems for inducing the differentiation of umbilical cord blood hematopoietic stem and progenior cells (HSPC) to erythroid cells.@*METHODS@#The CD34 cells from umbilical blood munonuclear cells were sorted by using the magnetic beads, and were inoculated into 3 different of culture systems (system 1, 2 and 3 respectively), to induce erythrold differentiation by 3 stage culture. The living cells were counted in different differentiation stages and were observed by Wright-Giemsa staining; the expression of CD71 and CD235a on cell surface was detected by flow cytometry, the erythroid differentiation pteency was detected via colony-forming test.@*RESULTS@#The ability of system 2 to promote the HSPC proliferation was the strongest, the efficacy of system 3 to promote the erythroid differentiation of HSPC was the most optimal; the proliferation ability of cells cultured in system 2 for 2-15 days all was higher than that of cells cutured in system 1 and 3 (P＜0.05). The flow cytometry detection showed that the expression of CD71 and CD235a on surface of cells cultured in system 3 was the highest, the CD235a percentage on day 15 of differentiation in system 3 was (92.33±3.89)%, that in system 2 was (84.67±3.12)%, while that in system 1 was (72.17±6.83)% (P＜0.05). Cell morplologic detection showed that throid differentiation was accelerated on day 12, the percentage of orthochromatic erythrocytes in system 3 was (67.67±2.08)% which was 10.69 and 25.34 times higher than that in system 2 and 1 respectively (P＜0.05). The colony-forming test showed the ratio of BFU-E in system 3 increased gradually on day 3-9 (r=0.99, P＜0.05), which was significanlly higher than that in system 2 and 1 on day 9 (90.35±5.52% vs 77.06±2.26% and 74.50±3.95%).@*CONCLUSION@#Culture system 3 is the most effective serum-free erythroid differentiation system, and the culture system 2 is the most powerful HSPC proliferation system. This study results provide a technical basis for further efficiently increasing and inducing the erythroid proliferation and differentiation of HSPC, and also provide culture system in vitro for the clinical application and basic research.

Long-Term Culture of Organotypic Hippocampal Slice from Old 3xTg-AD Mouse: An ex vivo Model of Alzheimer's Disease

OBJECTIVE: Conventional methods for organotypic hippocampal tissue slice culture (OHSC) have shown several disadvantages or limitations regarding age of animals used, duration of culture and difficulty using neurodegenerative models. Therefore, we tried to establish OHSC from old 3xTg-Alzheimer’s disease (AD) mice for longer period (over 4 weeks) and to validate utility of this system as a valid platform for translational neuroscience of AD. METHODS: OHSC was performed with old 3xTg-AD mice (12–14 months), old wild type mice (12–14 months) and young 3xTg-AD mice (2–4 months) using serum-free medium for 4 weeks. Hippocampal structure was evaluated by 4’, 6-diamidino-2-phenylindole (DAPI) intensity and neuronal metabolism was measured by Alamarblue assay. Pathologic characteristics of AD were also investigated; β-amyloid levels by ELISA, amyloid plaque deposition by Thioflavin-S staining, and glial activation by immunohistochemistry. RESULTS: Following 4-week culture in serum-free media, hippocampal cells and layers were well preserved in cultured slices from old AD mice as was in those from young AD and old wild type mice. On the contrary, excessive regression of total visible cells was observed in conventional serum-containing medium regardless of genotype of mice. In parallel with this well preserved structure, major pathologic characteristics of AD were also well manifested in hippocampal slices from old AD mice. CONCLUSION: Our findings suggest that long-term OHSC from old 3xTg-AD mouse can serve as a promising ex vivo system for studies on pathophysiology of AD, especially with the minimum number of sacrifice of experimental animals.

Efficacy of Human Platelet Rich Fibrin Exudate vs Fetal Bovine Serum on Proliferation and Differentiation of Dental Pulp Stem Cells

BACKGROUND AND OBJECTIVES: The imperative role of dental pulp stem cells (DPSCs) in regenerative therapy demands an in-vitro expansion which must deal with the safety and ethical problems associated with fetal bovine serum (FBS). The primary aim of this study was to compare the effects of human platelet rich fibrin (hPRF) exudate Vs FBS on proliferation and osteodifferentiation of human dental pulp stem cells (hDPSCs). The secondary one was to determine the optimum concentration of hPRF exudate inducing hDPSCs proliferation and osteodifferentiation. METHODS: The direct method was used to prepare hPRF exudate. hDPSCs were isolated from impacted mandibular third molars of twelve donors by the outgrowth method. For cell viability and proliferation rate testing, 96 well plates were used and the assay was done in duplicate and the trial repeated four times under the same conditions. Six wells were used to contain 10% FBS, serum free media, 1%, 5%, 10% and 20% concentrations of hPRF exudates, respectively. The proliferation assay was carried out by MTS tetrazolium cell proliferation assay kit and Elisa reader. The study design for osteodifferentiation protocol was exactly as the proliferation one and instead the assay was carried out by alizarin red with Elisa reader. RESULTS: Compared to 10% FBS, 10% hPRF exudate was the optimum concentration for hDPSCs proliferation, while 1% hPRF exudate was the optimum concentration for osteodifferentiation of hDPSCs. CONCLUSIONS: Avoiding the risk of zoonosis which may be occurred with FBS, it is recommended to use 10% hPRF exudate for proliferation and 1% for osteodifferentiation.

LPS Sensing Mechanism of Human Astrocytes: Evidence of Functional TLR4 Expression and Requirement of Soluble CD14

Among a myriad of pathogen-associated molecular pattern-sensing receptors, toll-like receptors (TLRs) are the principal core sensors of the host. Despite intensive studies for the expression of TLRs and their roles in the central nervous system, controversies remain regarding the expression and the function of TLR4 in human astrocytes. In order to clarify this issue, we attempted to verify functional expression of TLR4 in human astrocytes. Using Reverse transcription-polymerase chain reaction (RT-PCR), we confirmed that the human astrocytes express the TLR4 constitutively. To determine the function of TLR4, astrocytes were treated with TLR4 ligand or lipopolysaccharide (LPS), and then inflammatory cytokines expressions were checked using RT-PCR and enzyme-linked immunosorbent assay. Nuclear factor (NF)-κB activation was checked using electrophoretic mobility shift assay. Treatment of astrocytes with LPS increased tumor necrosis factor (TNF)-α, interleukin (IL)-6 and IL-8 expression and induced NF-κB activation. Neutralizing anti-TLR4 antibody blocked the effect of LPS on cytokine production and NF-κB activation in astrocytes. The effect of LPS on cytokine production and NF-κB activation was shown in the presence of serum but not in the absence of serum. Therefore, we investigated the sensing mechanism of LPS in human astrocytes. Human astrocytes were treated with LPS following neutralizing anti-CD14 antibody treatment in the presence of serum. Neutralizing anti-CD14 antibody treatment abolished the effect of LPS on cytokine expression and NF-κB activation. Additionally, supplement of recombinant CD14 in serum-free media induced LPS effect on cytokine production and NF-κB activation. In these results, we showed that human astrocytes constitutively express functional TLR4 and require soluble CD14 to recognize LPS.

A modified method by differential adhesion for enrichment of bladder cancer stem cells

ABSTRACT Purpose: In a previous study the vaccine was effective against bladder cancer in a mouse model. However, a small portion of tumors regrew because the vaccine could not eliminate bladder cancer stem cells (CSCs). In this study, we showed a modified method for the isolation of bladder CSCs using a combination of differential adhesion method and serum-free culture medium (SFM) method. Materials and Methods: Trypsin-resistant cells and trypsin-sensitive cells were isolated from MB49, EJ and 5637 cells by a combination of differential adhesion method and SFM method. The CSCs characterizations of trypsin-resistant cells were verified by the flow cytometry, the western blotting, the quantitative polymerase chain reaction, the resistance to chemotherapy assay, the transwell assay, and the tumor xenograft formation assay. Results: Trypsin-resistant cells were isolated and identified in CSCs characters, with high expression of CSCs markers, higher resistance to chemotherapy, greater migration in vitro, and stronger tumorigenicity in vivo. Conclusion: Trypsin-resistant cells displayed specific CSCs properties. Our study showed trypsin-resistant cells were isolated successfully with a modified method using a combination of differential adhesion method and SFM method.

Bisphenol A alters glucose metabolism in rat Sertoli cells in vitro / 中华男科学杂志

<p><b>OBJECTIVE</b>To observe the influence of different concentrations of bisphenol A (BPA) on glucose metabolism and lactate dehydrogenase (LDH) expression in rat Sertoli cells in vitro and investigate the mechanisms of BPA inducing male infertility.</p><p><b>METHODS</b>Using two-step enzyme digestion, we isolated Sertoli cells from male Wistar rats and constructed a primary Sertoli cell system, followed by immunohistochemical FasL staining. We randomly divided the Sertoli cells into a control group to be cultured in the serum-free minimal essential medium (MEM) plus dimethyl sulfoxide (DMSO) and three experimental groups to be treated with 100 nmol/L, 10 μmol/L, and 1 mmol/L BPA, respectively, in the MEM plus DMSO. After 48 hours of treatment, we measured the proliferation of the cells by CCK-8 assay, determined the concentrations of metabolites by NMR spectroscopy, and detected the expression of LDH in the Sertoli cells by RT-PCR and Western blot.</p><p><b>RESULTS</b>The purity of the isolated Sertoli cells was (96.05 ± 1.28)% (n = 10). Compared with the control group, the 100 nmol/L, 10 μmol/L, and 1 mmol/L BPA groups showed no remarkable changes in the proliferation of Sertoli cells ([98 ± 8]%, [96 ± 3]%, and [95 ± 3]%, P >0.05), but the 10 μmol/L and 1 mmol/L of BPA groups exhibited significantly decreased concentrations of intracellular glucose ([3.89 ± 0.07] vs [3.36 ± 0.24] and [3.04 ± 0.21] pmol/cell, P <0.05) and lactate ([0.43 ± 0.06] vs [0.29 ± 0.05] and [0.20 ± 0.03] pmol/cell, P <0.05). The expression of LDH mRNA was decreased with the increased concentration of BPA, while that of LDH protein reduced only in the 1 mmol/L BPA group (P <0.05).</p><p><b>CONCLUSION</b>High-concentration BPA decreases the expression of LDH and alters glucose metabolism in Sertoli cells, and therefore may reduce the provision of lactate for germ cells and impair spermatogenesis.</p>

Silymarin Protects Umbilical Cord-Derived Mesenchymal Stem Cells against Apoptosis Induced by Serum-Deprivation / 中国实验血液学杂志

<p><b>OBJECTIVE</b>To investigate the protection of silymarin against the human mesenchymal stem cell (MSC) apoptosis induced by serum deprivation and its underlying mechanism.</p><p><b>METHODS</b>Human umbilical cord MSCs were cultured in the absence of serum, and the silymain of different concentration (1-10 µg/ml) was added into the medium. MTT test was performed to observe the cell proliferation status. After being cultured for 72 hours, the cells were collected, and flow cytometry with Annexin-V-PI double-staining was used to detect the apoptotic cells from the control and silymarin-treated groups. Furthermore, the intracellular contents of BAX and BCL-2 were detected by Western blot for exploring the potential mechanism.</p><p><b>RESULTS</b>The silymarin promoted the proliferation of human UC-MSCs in a dose-dependent manner, reaching its maximal at a dose of 5 µg/ml. Moreover, silymarin could inhibit the serum deprivation-induced apoptosis of MSCs and, the inhibitory rate reached up to 30% when it was added at a concentration of 5 µg/ml. The content of intracellular BAX was obviously elevated after serum-deprivation treatment, and this increase could be blunted by the addition of silymarin. Meanwhile, the content of BCL-2 was not obviously changed.</p><p><b>CONCLUSION</b>The silymarin can stimulate MSC growth and inhibit the apoptosis of MSCs probably by the mitochondria pathway.</p>

Antiangiogenic drugs enhance the ability of invasion and metastasis of breast cancer cells under serum starvation and hypoxia / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To investigate the ability of invasion and migration of breast cancer MDA-MB-231 cells under serum starvation and hypoxia, and the effect of antiangiogenic drugs, rh-endostatin and bevacizumab, on the ability of invasion and migration of breast cancer cells under serum starvation and/or hypoxia, in order to explore the potential risk of antiangiogenic therapy in clinics.</p><p><b>METHODS</b>The cells were randomized into 4 groups, i.e., group A: 10% fetal bovine serum (FBS) group; group B: hypoxia + 10% FBS group; group C: serum starvation group; group D: hypoxia + serum starvation group; each group was further divided into three subgroups as blank control, treated with rh-endostatin and bevacizumab, respectively. Cell counting kit-8 (CCK-8) was used to assess the inhibition rate of cell growth induced by endostatin and bevacizumab, in order to determine the proper working concentration and time of the two drugs. Transwell assay was conducted to detect the cell invasion and migration in vitro. The expressions of c-Met and MMP-9 were detected by Western blot. The cells treated with rh-endostatin or bevacizumab under serum starvation were tested by hybridization using Exiqon miBase 18.0 microarray. The miRNAs which exibited significant differences (P < 0.05) in miRNA hybridization were verified by real-time PCR assay.</p><p><b>RESULTS</b>CCK-8 assay showed that the inhibition rates of MDA-MB-231 cells cultured with 800 mg/L rh-endostatin for 48 h and 24 h were (32.2 ± 2.5)% and (27.0 ± 1.3)%, respectively, showing a significant difference (P = 0.023). The inhibition rates of MDA-MB-231 cells cultured with 80 mg/L bevacizumab for 48 h and 24 h were (30.5 ± 1.4) % and (26.1 ± 2.4) %, respectively, showing also a significant difference (P = 0.015). The Transwell assay showed that in the starvation blank group, the number of invaded and penetrated cells were 28.8 ± 2.2 and 31.4 ± 1.5, respectively, significantly different from that in the rh-endostatin and bevacizumab groups (P < 0.05). The relative expressions of c-Met and MMP-9 were 0.213 ± 0.017 and 0.542 ± 0.048, respectively, with a significant difference from those of the groups treated with each drug (P < 0.05 for both). The numbers of penetrated cells in the Transwell assay treated with rh-endostatin in hypoxia were 17.5 ± 2.1 and 16.5 ± 2.8, respectively, and the numbers of penetrated cells in the Transwell assay treated with bevacizumab were 16.3 ± 3.5 and 17.5 ± 2.4, respectively, showing no significant difference among them (P > 0.05 for both). The ability of migration and invasion of MDA-MB-231 cells and the expression of c-Met and MMP-9 were not impacted by hypoxia (P > 0.05). Real-time PCR assay showed that only the levels of miR-2355 and miR375 were significantly and stably decreased in the cells which had increased ability of invasion and migration. The relative expression levels of miR375 and miR-2355 in the serum starvation blank group were 0.550 ± 0.036 and 0.852 ± 0.121, respectively, significantly lower than that in the groups treated with rh-endostatin or bevacizumab (P<0.05). In the serum starvation group, the expression levels of miR375 and miR-2355 of cells treated with rh-endostatin were 0.295 ± 0.012 and 0.253 ± 0.011, and the expression levels of cells treated with bevacizumab were 0.234 ± 0.020 and 0.309 ± 0.022, respectively, (P > 0.05 for all). Compared with the serum starvation blank group, the expression levels of miR2355 and miR375 were significantly decreased when cells were treated with rh-endostatin/bevacizumab under serum starvation, but no significant difference was found between the two drugs (P > 0.05). However, hypoxia did not affect the expressions of miR2355 and miR375 (P > 0.05).</p><p><b>CONCLUSIONS</b>The results of this study suggest that serum starvation can increase the ability of invasion and migration of breast cancer cells. Furthermore, both rh-endostatin and bevacizumab may enhance their invasion and penetration ability under serum starvation condition.</p>

Comparison of Serum-Free Media in RBC Differentiation from Human Hematopoietic Stem Cells / 대한수혈학회지

BACKGROUND: Research on RBC production from hematopoietic stem cells has been conducted competitively in many countries. However those were in vitro successes and many hurdles still remain for large scale transfusable RBC production from stem cells. A need for large volume of culture media is a crucial factor for culture condition which researchers must overcome. In this study, we evaluated the efficiency of two commercial serum-free media, StemPro(R)-34 SFM and Stemline II hematopoietic stem cell expansion medium, in RBC differentiation from cord derived stem cells. METHODS: We cultured cord derived CD34+ cells in vitro and evaluated over the periods of 7 days, 14 days, 17 days and 21 days in culture for expanded cell count, cell morphology and differential count using the Wright Giemsa stain. RESULTS: Cell expansion and RBC differentiation developed rapidly in Stemline media compared to StemPro media. Enucleated RBCs were observed at 10~14 culture days and orthochromatic erythroblasts were shown up to 50% among culture cells at 17 days in Stemline media. The enucleated RBCs were observed at 17 days in StemPro Media. Although the erythroblasts in StemPro media are slow at differentiation, they maintain continuous expansion up to 21 days. CONCLUSION: In Stemline media, the expansion and differentiation to mature RBCs are processed much faster, but the cell condition slows down after 17 days. In the RBC production aspects, Stemline media is better than StemPro media as a rapid differentiation because it reduces the cost due to in vitro short culture duration.

Biological behaviors of lung cancer stem-like cells from human large-cell lung cancer cell line H460 / 南方医科大学学报

<p><b>OBJECTIVE</b>To isolate lung cancer stem-like cells (LCSCs) from human large-cell lung cancer cell line NCI-H460 (H460) and explore their biological characteristics.</p><p><b>METHODS</b>H460 cells were cultured in serum-free medium in the presence of specific growth factors. Quantitative PCR (qPCR), flow cytometry and colony formation assay were performed to characterize the stemness of H460 spheres. Adherent H460 cells and H460 cell spheres were inoculated subcutaneously in nude mice and the tumor growth was assessed.</p><p><b>RESULTS</b>The isolated LCSCs from H460 cells in serum-free medium grew as floating cell spheres and exhibited stronger proliferative activity than H460 cells. Compared with H460 cells, H460 cells spheres showed higher expressions of stem cell markers Sox2, Oct4, and especially Nanog, and possessed a stronger tumorigenicity in nude mice.</p><p><b>CONCLUSION</b>The serum-free culture system can effectively enrich lung cancer stem cells from human lung cancer stem cell line H460, and the high expression of Nanog may importantly contribute to the maintenance of cancer stem cell-like properties of the isolated LCSCs.</p>

Study on the induction and differentiation of megakaryocyte progenitor cell derived from umbilical cord blood / 中华血液学杂志

<p><b>OBJECTIVE</b>To build a protocol of separation and induction of megakaryocytes derived from cord blood mononuclear cells.</p><p><b>METHODS</b>Red blood cells were precipitated by hydroxyethyl starch (HES). Mononuclear cells were obtained by density gradient centrifugation with Ficoll. The inducing efficiencies of megakaryocytes by using of different cytokine cocktails and culture media were analyzed.</p><p><b>RESULTS</b>The best choice for erythrocyte sedimentation and high efficiency of nucleated cells retrieving were obtained by using of 1.5% HES. The isolated cord blood mononuclear cells were cultured with domestic serum-free medium supplemented with 116t (IL-11, IL-6, TPO), st36(SCF, TPO, IL-3, IL-6), pt36 (PDGF,TPO,IL-3,IL-6) or pst36 for 7 days. St36 group (50 ng/ml SCF, 50 ng/ml TPO, 20 ng/ml IL-3 and 50 ng/ml IL-6) yielded the most CD41/CD61 positive [(6.79±1.97)×10⁴]. The cell viability [(82.85 ± 0.64)%] of st36 group by using of imported serum-free medium was better than [(60.90±6.93)%] that in domestic medium on day 7 after induction, and CD41/CD61 positive cells count [(18.60±1.97)×10⁴] were more than domestic serum-free medium group. Therefore, we chose imported serum-free medium containing st36 to induce cord blood mononuclear cells. After a prolonged culture, the total cell numbers increased accompanied with an elevated percentage of CD41/CD61 positive cells, which reached (54.27 ± 6.31)% on day 14. Wright-Giemsa staining showed that different phase cells, such as megakaryoblast, promegakaryocyte and granular megakaryocyte, occurred after 10 days'culture. Clone forming unit-megakarocytes (CFU-MK) assay showed that the colonies count increased with the prolonged incubation. CFU-MK colonies were [1 236.0±32.9] on day 14, which was higher than that in medium without induction (P<0.01). Platelets from megakaryocytes showed agglutination function after 10 days'culture.</p><p><b>CONCLUSION</b>1.5% HES was the best solution to precipitate erythrocytes. The combination of an imported serum-free medium with IL-3, IL-6, SCF and TPO showed better induction efficiency than domestic medium or other cytokine cocktails. Meanwhile, induced megakaryocytes produced functional platelets.</p>

A Milk Protein, Casein, as a Proliferation Promoting Factor in Prostate Cancer Cells

PURPOSE: Despite most epidemiologic studies reporting that an increase in milk intake affects the growth of prostate cancer, the results of experimental studies are not consistent. In this study, we investigated the proliferation of prostate cancer cells treated with casein, the main protein in milk. MATERIALS AND METHODS: Prostate cancer cells (LNCaP and PC3), lung cancer cells (A459), stomach cancer cells (SNU484), breast cancer cells (MCF7), immortalized human embryonic kidney cells (HEK293), and immortalized normal prostate cells (RWPE1) were treated with either 0.1 or 1 mg/mL of alpha-casein and total casein extracted from bovine milk. Treatments were carried out in serum-free media for 72 hours. The proliferation of each cell line was evaluated by an 3-(4,5-Dimethyl-thiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay. RESULTS: alpha-Casein and total casein did not affect the proliferations of RWPE1, HEK293, A459, SNU484, MCF7, HEK293, or RWPE1 cells. However, PC3 cells treated with 1 mg/mL of alpha-casein and casein showed increased proliferation (228% and 166%, respectively), and the proliferation of LNCaP cells was also enhanced by 134% and 142%, respectively. The proliferation mechanism of alpha-casein in PC3 and LNCaP cells did not appear to be related to the induction of Insulin-like growth factor-1 (IGF-1), since the level of IGF-1 did not change upon the supplementation of casein. CONCLUSIONS: The milk protein, casein, promotes the proliferation of prostate cancer cells such as PC3 and LNCaP.

A Milk Protein, Casein, as a Proliferation Promoting Factor in Prostate Cancer Cells

PURPOSE: Despite most epidemiologic studies reporting that an increase in milk intake affects the growth of prostate cancer, the results of experimental studies are not consistent. In this study, we investigated the proliferation of prostate cancer cells treated with casein, the main protein in milk. MATERIALS AND METHODS: Prostate cancer cells (LNCaP and PC3), lung cancer cells (A459), stomach cancer cells (SNU484), breast cancer cells (MCF7), immortalized human embryonic kidney cells (HEK293), and immortalized normal prostate cells (RWPE1) were treated with either 0.1 or 1 mg/mL of alpha-casein and total casein extracted from bovine milk. Treatments were carried out in serum-free media for 72 hours. The proliferation of each cell line was evaluated by an 3-(4,5-Dimethyl-thiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay. RESULTS: alpha-Casein and total casein did not affect the proliferations of RWPE1, HEK293, A459, SNU484, MCF7, HEK293, or RWPE1 cells. However, PC3 cells treated with 1 mg/mL of alpha-casein and casein showed increased proliferation (228% and 166%, respectively), and the proliferation of LNCaP cells was also enhanced by 134% and 142%, respectively. The proliferation mechanism of alpha-casein in PC3 and LNCaP cells did not appear to be related to the induction of Insulin-like growth factor-1 (IGF-1), since the level of IGF-1 did not change upon the supplementation of casein. CONCLUSIONS: The milk protein, casein, promotes the proliferation of prostate cancer cells such as PC3 and LNCaP.

NCAM140 and pCREB Expression after Tianeptine Treatment of SH-SY5Y Cells

OBJECTIVE: Antidepressants Modulate Neuronal Plasticity. Tianeptine, An Atypical Antidepressant, Might Be Involved In The Restoration Of Neuronal Plasticity; It Primarily Enhances The Synaptic Reuptake Of Serotonin. Ncam140 Is Involved In Neuronal Development Processes, Synaptogenesis And Synaptic Plasticity. We Investigated The Effect Of Tianeptine On The Expression Of Ncam140 And Its Downstream Signaling Molecule In The Human Neuroblastoma Cell Line Sh-sy5y. METHODS: NCAM protein expression was measured in human neuroblastoma SH-SY5Y cells that were cultivated in serum-free media and treated with 0, 10, or 20 microM tianeptine for 6, 24, or 72 hours. NCAM140 expression in the tianeptine treatment group was confirmed by Western blot, and quantified through measurement of band intensity by absorbance. CREB and pCREB expression was identified after treatment with 20 microM tianeptine for 6, 24, and 72 hours by Western blot. RESULTS: Compared to cells treated for 6 hours, cells treated with 0 or 10 microM tianeptine for 72 hours showed a significant increase in NCAM140 expression and cells treated with 20 microM tianeptine showed a significant increase after 24 and 72 hours. The pCREB level in cells treated with 20 microM tianeptine increased in time-dependent manner. CONCLUSION: Our findings indicated that the tianeptine antidepressant effect may occur by induction of NCAM140 expression and CREB phosphorylation.

Comparación del cultivo "in vitro" de Toxoplasma gondii cepa RH en las líneas celulares Hep-2 y Vero / Comparison of "in vitro" culture of Toxoplasma gondii RH strain in Hep-2 and Vero cell lines

Introducción: La toxoplasmosis es una zoonosis causada por Toxoplasma gondii, parásito intracelular obligado capaz de replicarse en todas las células nucleadas, permitiendo su aislamiento y mantenimiento en cultivo celular. Objetivo: Comparar el cultivo de Toxoplasma gondii (RH), en células Hep-2 y Vero empleadas para propagación parasitaria. Métodos: Se optimizaron las condiciones para cultivo de Toxoplasma gondii (RH), en células Vero y Hep-2; se sembraron 500.000 y 1.000.000cel./mm3 y se infectaron 1.000.000 y 2.000.000taq/mm3 respectivamente, se hizo seguimiento hasta las 120 horas para determinar invasión celular, porcentaje de rosetas, de viabilidad y rendimiento de taquizoitos. Resultados: A las 48 horas de incubación se evidenció el 90% de invasión parasitaria en las dos líneas celulares así como el mayor recuento de rosetas; a las 120 horas se obtuvieron los mayores recuentos de taquizoitos extracelulares y un mayor índice de rendimiento de 185,9 en las células Hep-2, en la concentración de 500.000cel./mm3 y 1.000.000taq/mm3. Se obtuvo una viabilidad parasitaria promedio superior al 80% para las dos líneas celulares. Conclusiones: Se obtuvo un mayor rendimiento parasitario viable en las células Hep-2 por lo que esta línea celular puede considerarse como el mejor modelo para la propagación y mantenimiento parasitario de T. gondii (RH).

Introduction: Toxoplasmosis is a zoonosis caused by Toxoplasma gondii, which is an obligate intracellular parasite capable of replicate itself in all nucleated cells, allowing their isolation and maintenance in cell culture. Objective: To compare cultivation Toxoplasma gondii (RH) in Hep-2 cells and Vero employed to spread parasitic. Methods: The conditions were optimized for cultivation of Toxoplasma gondii (RH) in Vero and Hep-2 cells lines, 500.000 and 1.000.000cel./mm³ were seeded and 1.000.000 and 2.000.000taq/mm³ were infected respectively, a track to determine cell invasion, percentage of rosettes and viability and efficiency of tachyzoites was made until the 120 hours. Results: After 48 hours of incubation, 90% of parasite invasion was evident in both cell lines as well as the largest count rosettes. At 120 hours higher counts of extracellular tachyzoites and a higher rate of performance of 185.9 in Hep-2 cells at concentration of 1.000.000taq/mm³ and 500.000cel./mm³ were obtained. Average parasite viability over 80 % was obtained for both cell lines. Conclusions: Higher parasitic performance was obtained viable in Hep-2 cells, so that this cell line can be considered as the preferred model for the propagation and maintenance of T. gondii (RH).

Culture of bovine ovarian follicle wall sections maintained the highly estrogenic profile under basal and chemically defined conditions

Follicle cultures reproduce in vitro the functional features observed in vivo. In a search for an ideal model, we cultured bovine antral follicle wall sections (FWS) in a serum-free defined medium (DM) known to induce 17β-estradiol (E2) production, and in a nondefined medium (NDM) containing serum. Follicles were sectioned and cultured in NDM or DM for 24 or 48 h. Morphological features were determined by light microscopy. Gene expression of steroidogenic enzymes and follicle-stimulating hormone (FSH) receptor were determined by RT-PCR; progesterone (P4) and E2 concentrations in the media were measured by radioimmunoassay. DM, but not NDM, maintained an FWS morphology in vitro that was similar to fresh tissue. DM also induced an increase in the expression of all steroidogenic enzymes, except FSH receptor, but NDM did not. In both DM and NDM, there was a gradual increase in P4 throughout the culture period; however, P4 concentration was significantly higher in NDM. In both media, E2 concentration was increased at 24 h, followed by a decrease at 48 h. The E2:P4 ratio was higher in DM than in NDM. These results suggest that DM maintains morphological structure, upregulates the expression of steroidogenic enzyme genes, and maintains steroid production with a high E2:P4 ratio in FWS cultures.