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Haematopoietic stem/progenitor cell (HSPC) integrates intracellular signal network from growth factors (GFs) and utilizes its proliferation feature to generate high yields of transplantable cells upon ex vivo culture. However, the molecular basis for HSPC activation and proliferation is not completely understood. The goal of this study was to investigate proliferation regulator in the downstream of GFs and develop HSPC expansion strategy. Microarray and Ingenuity Pathway Analysis were performed to evaluate differentially expressed genes in cytokine-induced CD34+ cells after ex vivo culture. We identified that MEK1 was a potential HSPC proliferation regulator, which represented indispensable roles and MEK1 silence attenuated the proliferation of HSPC. Notably, 500 nM MEK1 agonist, PAF C-16, increased the numbers of phenotypic HSPC and induced cell cycling of HSPC. The PAF C-16 expanded HSPC demonstrated comparative clonal formation ability and secondary expansion capacity compared to the vehicle control. Our results provide insights into regulating the balance between proliferation and commitment of HSPC by targeting the HSPC proliferation-controlling network. This study demonstrates that MEK1 critically regulates HSPC proliferation and cell production in the ex vivo condition for transplantation.

Natural killer-92 cells (NK-92 cells) need to be efficiently expanded by serum-free culture in vitro to meet clinical requirements. Fatty acids mainly provide substrates for energy production, which is of crucial importance to meet the energy demands of highly proliferating cells. This study optimized the medium (EM) for NK-92 cells by designing an experiment to expand cells efficiently. EM, an in-house designed chemically defined serum-free medium, was used as the basal medium. Fatty acids as additive ingredients were screened and optimized by the experimental design method. Three additives, arachidonic acid, myristic acid and palmitoleic acid, were screened; therefore, the optimized medium was named EM-FA. The total cell expansion of NK-92 cells in EM-FA was 72.61±11.95-fold on day 8, which was significantly higher than the 28.55±8.67-fold expansion in EM. To explore the mechanism by which fatty acids promote NK-92 cell expansion, the cell growth kinetics and metabolic characteristics in EM-FA were analyzed. The results showed that NK-92 cells in EM-FA were rapidly expanded while maintaining their cell phenotype and cytotoxicity and enhancing the oxygen consumption rate and mitochondrial function. Fatty acids promoted ATP production to elevate the energy flux for better cell expansion. This study developed an expansion strategy of NK-92 cells in vitro to facilitate their clinical application. KEY POINTS: • Arachidonic acid, myristic acid and palmitoleic acid in serum-free medium were optimized by experimental design to enable the rapid expansion of NK-92 cells in vitro. • Fatty acids upregulated oxidative phosphorylation levels and improved the energy metabolism of NK-92 cells.

Epigallocatechin-3-gallate (EGCG) is a kind of flavonoids and has the ability to promote differentiation of mesenchymal stem cells (MSCs) into osteoblasts. However, the EGCG is easily metabolized by cells during cell culture, which reduces its bioavailability. Therefore, in this paper, EGCG-loaded chitosan nanoparticles (ECN) were fabricated and entrapped into chitosan/alginate (CS/Alg) scaffolds to form CS/Alg-ECN scaffolds for improving the bioavailability of EGCG. The human umbilical cord mesenchymal stem cells (HUMSCs) were cultured on CS/Alg-ECN scaffolds to induce osteogenic differentiation. The results indicated that the CS/Alg-ECN scaffolds continuously released EGCG for up to 16 days. Besides, these results suggested that CS/Alg-ECN scaffolds promoted osteoblast differentiation through activating Wnt/β-catenin signaling pathway. Collectively, this study demonstrated that the entrapment ECN into CS/Alg scaffolds was a promising strategy for promoting osteogenesis of MSCs.

Antibacterial hydrogels have received intensive interest in soft tissue repair, especially for preventing infections associated with impaired wound healing. However, developing an inherent antibacterial hydrogel dressing with antifouling ability without causing secondary damage to repaired tissues has proven to be promising and challenging. In this work, a mussel-inspired zwitterionic sulfobetaine acrylamide hydrogel incorporated with laponite (LAP) nanoplatelets and methacrylamide dopamine (DMA) has been developed for effective wound dressings, where LAP nanoplatelets and DMA endow the hydrogel with enhanced mechanical strength and substance adhesiveness, respectively. Moreover, LAP nanoplatelets could immobilize hydrophobic curcumin to form complexes, realizing the controlled release of curcumin to provide antimicrobial activities. In vitro results showed that hydrogels did not cause obvious cytotoxicity and hemolysis, but they still can well resist bovine serum albumin (BSA) adsorption. Wound closure and histopathological experiments have been performed in vivo to evaluate the therapeutic effects of the hydrogel by a full-thickness skin defect mouse model, and the results demonstrated that infected wounds could be well closed after being treated with the hydrogel for 15 days. Meanwhile, the full re-epithelialization and total formation of new connective tissues can be clearly observed by histological analysis. Moreover, the hydrogel could be easily removed from recovered tissues without causing secondary damage. Therefore, this antifouling and antimicrobial hydrogel dressing with suitable adhesiveness would provide a new strategy for wound healing without causing secondary damage.

Effective nutrient transport and appropriate mechanical stimulation play important roles in production of tissue-engineered bone grafts. In this study, an experimental set-up for magnetic-driven dynamic culture of cells was designed to mimic the microenvironment of the bone tissue. Here, its ability to contribute to osteogenic differentiation was investigated by inoculating human umbilical cord mesenchymal stem cells (HUMSCs) on magnetic scaffolds. The cytocompatibility of the developed magnetic scaffolds was verified for HUMSCs. Magnetic scaffolds seeded with HUMSCs were exposed to magnetic fields. The results showed that magnetic fields did not affect cell activity and promoted HUMSCs osteogenic differentiation. The magnetic scaffolds were magnetically driven for dynamic culture in the experimental set-up to evaluate the influence of HUMSCs osteoblast differentiation. The results indicated that magnetic-driven dynamic culture increased cell alkaline phosphatase (ALP) activity (p p

Ex vivo expansion is critical in facilitating the application of hematopoietic/progenitor stem cells (HSPCs) for regenerative therapies. Wnt signaling is implicated in the expansion and self-renewal maintenance of HSPCs. However, a reasonable method to regulate Wnt signaling in ex vivo cultures to achieve robust expansion of HSPCs has not yet been investigated. Here, cord blood-derived CD34+ cells were cultured with the activator of Wnt signaling 6-bromoindirubin-3′-oxime (BIO) under the following conditions: vehicle control (group A); BIO was added to the culture on days 0, 4, and 7 (group B); and BIO was added to the culture on days 0 and 7 (group C). Initial BIO treatment promoted the expansion of CD34+ cells on day 4. However, BIO supplementation on days 0 and 4 in group B attenuated HSPC expansion on day 7, while enhancing the multilineage commit potential and secondary expansion ability of expanded CD34+ cells. Based on this finding, an optimized BIO feeding strategy (group C) was proposed to support substantial expansion of HSPCs. After 10 days of culture, the expansion fold of CD34+ cells was 28.70 ± 0.46-folds, which was significantly higher than group A (16.20 ± 0.72-folds, p

The existing approaches of hematopoietic stem cells (HSCs) expansion in vitro were difficult to meet the needs of clinical application. While in vivo, HSCs efficiently self-renew in niche where they interact with three dimension extracellular matrix and stromal cells. Osteoblasts (OBs) are one of most significant stromal cells of HSCs niche. Here, we proposed a three-dimensional environment based on gallic acid grafted-chitosan (2c) scaffold and OBs differentiated from human umbilical cord mesenchymal stem cells (HUMSCs) to recapitulate the main components of HSCs niche. The results of alkaline phosphatase staining and alizarin red staining demonstrated that HUMSCs were successfully induced into OBs. The results showed that the expansions of CD34

The development of an effective cryopreservation method to achieve off-the-shelf and bioactive tissue-engineered constructs (TECs) is important to meet the requirements for clinical applications. The trehalose, a non-permeable cryoprotectant (CPA), has difficulty in penetrating the plasma membranes of mammalian cells and has only been used in combination with other cell penetrating CPA (such as DMSO) to cryopreserve mammalian cells. However, the inherent cytotoxicity of DMSO results in increasing risks with respect to cryopreserved cells. Therefore, in this study, permeable trehalose glycopolymers were synthesised for cryopreservation of TECs. The trehalose glycopolymers exhibited good ice inhibiting activities and biocompatibilities. Furthermore, the viability and function of TECs after cryopreservation with 5.0 wt% S2 were similar to those of the non-cryopreserved TECs. We developed an effective preservation strategy for the off-the-shelf availability of TECs.

Background Unlike conventional cultivation systems, liquid mixing in floating photobioreactors (PBRs) is solely induced by their hydrodynamic movement in response to waves, and this movement is affected by the wave conditions (wave height and wave period), the PBR configuration and the culture depth. However, to the best of our knowledge, a practical study of the hydrodynamic movements of PBRs has not been previously conducted. Results This study aims to investigate the hydrodynamic performance of floating PBRs in response to wave conditions. First, the effects of the experimental wave height (2–10 cm) and wave period (0.8–1.8 s) on movement was investigated using two 1.0 m2 PBR models: a square PBR (1.0 m/1.0 m; length/width) and a rectangular PBR (1.7 m/0.6 m). The results indicated that wave movement became not only more intense with increasing wave height, but also less intense when the wave period decreased. However, the square PBR experienced more intense movement than the rectangular PBR, but also little mooring force. The effects of culture depth (0.5, 1.0 and 2.0 cm) were investigated and the results showed that the culture depth significantly affected the hydrodynamic movements of the PBRs; however, the mooring forces were unaffected. Finally, the movement and mooring-line forces of PBRs equipped with different mooring systems were investigated. The use of two different mooring systems had little effect on PBR movement; however, a mooring system with floaters was able to significantly reduce the mooring line forces compared to a system without floaters. During this study, the greatest force (10.5 N) was found for the rectangular PBR using a mooring system without floaters, whereas the lowest force (0.67 N) was observed for a rectangular PBR using a mooring system with floaters. Conclusions These studies have provided basic data describing the fluid dynamics of floating PBRs; as well as their structural design and scale up. These results also provide guidance for the selection of ocean fields with suitable wave conditions; as well as a proper mooring methods to ensure safe operation.

Ex vivo expansion is an effective strategy to acquire cytokine-induced killer (CIK) cells needed for clinical trials. In this work, the effects of dynamic suspension culture, which was carried out by shake flasks on a shaker, on CIK cells were investigated by the analysis of expansion characteristics and physiological functions, with the objective to optimize the culture conditions for ex vivo expansion of CIK cells. The results showed that the expansion folds of total cells in dynamic cultures reached 69.36 ± 30.36 folds on day 14, which were significantly higher than those in static cultures (9.24 ± 1.12 folds, P0.05), however, the proportions of CD3

Intracellular reactive oxygen species (ROS) play important roles in the ex vivo expansion of hematopoietic stem and progenitor cells (HSPCs). In this study, the effects of resveratrol (RES), on the ex vivo expansion of HSPCs were investigated by analyzing CD34+ cells expansion and biological functions, with the objective to optimize ex vivo culture conditions for CD34 + cells. Among the five tested doses (0, 0.1, 1, 10, 20, and 50 μM), 10 μM RES was demonstrated to be the most favorable for ex vivo CD34 + cells expansion. In the primary cultures, 10 μM RES favored higher expansion folds of CD34 + cells, CD34 + CD38 - cells, and colony-forming units (CFUs) ( P < 0.05). It was found that the percentages of primitive HSPCs (CD34 + CD38 - CD45R - CD49f + CD90 + cells) in 10 μM RES cultures were higher than those without RES. Further, in the secondary cultures, expanded CD34 + cells derived from primary cultures with 10 μM RES exhibited significantly higher total cells and CD34 + cells expansion ( P < 0.05). In the semisolid cultures, the frequency of CFU-GM and total CFUs of 10 μM RES group were both higher than those of without RES group, demonstrating that CD34 + cells expanded with 10 μM RES possessed better biological function. Furthermore, the addition of 10 μM RES downregulated the intracellular ROS level via strengthening the scavenging capability of ROS, and meanwhile reducing the percentages of apoptotic cells in cultures. Collectively, RES could stimulate the ex vivo expansion of CD34 + cells, preserved more primitive HSPCs and maintain better biological function by alleviating intracellular ROS level and cell apoptosis in cultures.

Objective As an inhibitor of the AhR signalling pathway, StemRegenin 1 (SR1) not only promotes the expansion of CD34+ cells but also increases CD34− cell numbers. These CD34− cells influenced the ex vivo expansion of CD34+ cells. In this work, the effects of periodically removing CD34− cells combined with SR1 addition on the ex vivo expansion and biological functions of HSCs were investigated. Materials and methods CD34− cells were removed periodically with SR1 addition to investigate cell subpopulations, cell expansion, biological functions, expanded cell division mode and supernatant TGF‐β1 contents. Results After 10‐day culture, the expansion of CD34+ cells in the CD34− cell removal plus SR1 group was significantly higher than that in the control group and the SR1 group. Moreover, periodically removing CD34− cells with SR1 addition improved the biological function of expanded CD34+ cells and significantly increased the percentage of self‐renewal symmetric division of CD34+ cells. In addition, the concentration of total TGF‐β1 and activated TGF‐β1 in the supernatant was significantly lower than those in the control group and the SR1 group. RT‐qPCR results showed that the periodic removal of CD34− cells with cooperation from SR1 further reduced the expression of AhR‐related genes. Conclusions Periodic removal of CD34− cells plus cooperation with SR1 improved the expansion of CD34+ cells, maintained better biological function of expanded CD34+ cells and reduced the TGF‐β1 contents by downregulating AhR signalling., SR1 increased self‐renewal symmetric division of cord blood CD34+ cells. Removal of CD34− cells cooperated with SR1 increased ex vivo expansion of cord blood CD34+ cells. Removal of CD34− cells cooperated with SR1 further downregulated AhR signalling

Background Cancer stem cells (CSCs) have been proposed to be responsible for tumor recurrence and chemo-resistance. Previous studies suggested that miR-153 played essential roles in lung cancer. However, the molecular mechanism of miR-153 in regulating the stemness of non-small cell lung cancer (NSCLC) remains poorly understood. In this study, we investigated the role of miR-153 in regulation of the stemness of NSCLC. Methods The stemness property of lung stem cancer cells was detected by sphere formation assay, immunofluorescence, and Western blot. Luciferase reporter assay was performed to investigate the direct binding of miR-153 to the 3′-UTR of JAG1 mRNA. Animal study was conducted to evaluate the effect of miR-153 on tumor growth in vivo. The clinical relevance of miR-153 in NSCLC was evaluated by Rt-PCR and Kaplan-Meier analysis. Results MiR-153 expression was decreased in lung cancer tissues. Reduced miR-153 expression was associated with lung metastasis and poor overall survival of lung cancer patients. Jagged1, one of the ligands of Notch1, is targeted by miR-153 and inversely correlates with miR-153 in human lung samples. More importantly, we found that miR-153 inhibited stem cell-like phenotype and tumor growth of lung adenocarcinoma through inactivating the Jagged1/Notch1 axis. Conclusion MiR-153 suppresses the stem cell-like phenotypes and tumor growth of lung adenocarcinoma by targeting Jagged1 and provides a potential therapeutic target in lung cancer therapy.

A light-controlled porphyrinic photosensitizer release system was developed based on host–guest TPP–Azo/PEG–β-CD supramolecular amphiphiles, which could significantly enhance the efficiency of photodynamic therapy. TPP–Azo was prepared via esterification between TPP and Azo derivatives, and further used to construct supramolecular amphiphiles with PEG–β-CD. TEM images showed that TPP–Azo/PEG–β-CD amphiphiles can self-assemble into spherical micelles, and then disaggregate under irradiation with 365 nm UV light. The phototoxicity and bio-distribution of TPP–Azo/PEG–β-CD micelles against the MCF-7 cell line were also evaluated by MTT assay, flow cytometry and confocal scanning laser microscopy, respectively. According to MTT assay, the IC50 of the spherical micelle was 31.2 μg mL−1, but it became 20.6 μg mL−1 upon pre-irradiation with 365 nm UV light. This shows for the first time that UV light can well stimulate the release of porphyrin photosensitizers and improve the photodynamic therapy efficiency based on the system of host–guest supramolecular amphiphiles.

RNA-binding proteins (RBPs) play an essential role in regulating the function of RNAs in a cellular context, but our ability to control RBP activity in time and space is limited. Here, we describe the engineering of LicV, a photoswitchable RBP that binds to a specific RNA sequence in response to blue light irradiation. When fused to various RNA effectors, LicV allows for optogenetic control of RNA localization, splicing, translation and stability in cell culture. Furthermore, LicV-assisted CRISPR-Cas systems allow for efficient and tunable photoswitchable regulation of transcription and genomic locus labeling. These data demonstrate that the photoswitchable RBP LicV can serve as a programmable scaffold for the spatiotemporal control of synthetic RNA effectors.

Intracellular reactive oxygen species (ROS) accumulation during culture process compromise cord blood-derived hematopoietic stem/progenitor cells (CB-HSPCs) proliferation potential dramatically. In this work, the effects of hyperoside (Hyp) on CD34+ cells were investigated by the analysis of cell expansion and secondary expansion potential, with the objective to optimize the culture conditions for ex vivo expansion of HSPCs. The results showed that the expansion of total cells treated with 1 μM Hyp reached 54.9 ± 9.6 folds, which was significantly higher than that of control cells (42.0 ± 8.1 folds, P

Summary Aim The prevalence and mortality rates of lung cancer in Xuanwei, Yunnan, China, are the highest in the world. The severe indoor air pollution caused by smoky coals with high benzo (a)pyrene (BaP) and quartz levels is the main environmental factor. The aim of this study was to investigate methylation profiles of promoters in eight genes in primary non-small cell lung cancers (NSCLC) exposed to smoky coals. Materials and methods Candidate genes including CDKN2A, DLEC1, CDH1, DAPK, RUNX3, APC, WIF1 and MGMT were determined for the promoter methylation status using Nested methylation-specific PCR (nMSP) in primary 23 NSCLC tissues and in circulating tumor DNA (ctDNA) isolated from 42 plasma samples (9 matched to tissues) as well as 10 healthy plasma samples, using Sanger sequencing to verify the results. Results Seven of the 8 genes, except MGMT, had relatively high methylation frequencies ranging from 39%–74% in tissues. Moreover, methylation frequencies in five genes identified in lung cancer plasma were 45% for CDKN2A, 48% for DLEC1, 76% for CDH1, 14% for DAPK, 29% for RUNX3, with a relatively good concordance of methylation among 9 tissues and paired plasma. However, the genes from all healthy plasma showed no methylation. Conclusions A panel of genes including CDKN2A, DLEC1, CDH1, DAPK and RUNX3 may be used as potential epigenetic biomarkers for early lung cancer detection. CDH1 promoter methylation was associated with lung cancer metastasis in areas of air pollution from buring of smoky coals. DLEC1 and CDH1 exhibited specific high methylation frequencies, different from previous reports.

The treatment of pathogenic bacterial infection has long been the most serious threat to human life and attracted widespread attention. Herein, we construct a supramolecular photosensitizer platform based on carboxylatopillar[5]arene (CP5) and tetrafluorophenyl porphyrin functionalized with a quaternary ammonium group (TFPP-QA) for combating bacteria and dispersing biofilm via photodynamic treatment. By introducing the host macrocycle CP5 and host-guest interaction, the supramolecular photosensitizer has great biocompatibility and acid-responsiveness. On the one hand, the acid-triggered dissociation of TFPP-QA/CP5 could induce the porphyrin photosensitizer to target bacterial cells and disrupt the charge balance of bacterial membranes, enhance the permeability of the bacterial membrane. On the other hand, the TFPP-QA/CP5 antibacterial platform possesses superb reactive oxygen species (ROS) generation capability under light irradiation, leading to enchanced photodynamic antibacterial efficacy. The in vitro and in vivo studies show that the supramolecular photosensitizers exhibit high antibacterial efficiency and biofilm dissipation effect under 660 nm light irradiation. Therefore, it is anticipated that the rational design and intergation of photosensitizers and quaternary ammonium compounds through the supramolecular strategy would provide a promising prospect for clinical photodynamic antimicrobial therapy. This article is protected by copyright. All rights reserved.

HA/GO hydrogels were prepared by methacrylated GO (MeGO) and methacrylated HA (MeHA) via an in-situ free radical polymerization, and then a series of HA/GO hydrogels with highly porous structure were obtained. All hydrogels exhibited excellent water absorption ability. Additionally, the elastic moduli of hydrogels were clearly enhanced by GO. CD34 + cells cultured on HA/GO-0.05 hydrogel showed higher expansion of CD34 + cells and CD34 + CD38 − cells compared to the other three hydrogels. Therefore, HA/GO-0.05 hydrogels have a potential for clinical-applied ex vivo expansion of hematopoietic stem cells.

YBCO coils with epoxy resin impregnation tend to experience degraded performance, which is due to the mismatch of the thermal contraction coefficients among former, epoxy, and HTS conductors which will generate thermal stresses that induce delamination of the superconducting layer. Several coils have been fabricated and tested, using the YBCO wires from SuperPower Inc. (SP), and Shanghai Superconductor Technology Corporation (SSTC). No degradation of the coil performance was detected for small SP coils, even with epoxy resin impregnation. However, for SP coils and SSCT coils using more than 100 m of YBCO wires, they all exhibited degraded performance after the epoxy resin impregnation. A possible solution to this problem is proposed and a 400 m SSCT coil has been successfully fabricated and tested.

Long non-coding RNAs (lncRNAs) are known to be potential factors in promoting tumor progression. However, the function and mechanism of lncRNA XIST in non-small cell lung cancer (NSCLC) remains poorly understood. The expression levels of lncRNA XIST in NSCLC tissues and cell lines were detected with real-time PCR, and the correlation of the expression level of XIST with histopathological characteristics and prognosis was analyzed. The biological function of lncRNA XIST was validated through assays in vivo and in vitro. The expression of lncRNA XIST was significantly up-regulated in NSCLC tissues. In addition, overexpression of XIST was positively correlated with the advanced clinical status of tumors, as well as poor overall survival and DFS. A tumor suppressive effect was presented via functional knockdown of lncRNA XIST. Up-regulation of XIST enhanced the proliferation, migration, and invasion ability of NSCLC cells both in vivo and in vitro. Mechanically, it was indicated that XIST could serve as an endogenous competitive RNA modulating miR-744, leading to the miR-744/RING1 signaling pathway inhibition and Wnt/β-catenin signaling pathway activation. Taken together, it was confirmed here that XIST overexpression is associated with tumor progression phenotype and the newly discovered XIST/miR-744/RING1 axis, which could serve as a potential biomarker and therapeutic target for NSCLC.

Objective Ex vivo expansion is an effective way to produce cytokine‐induced killer (CIK) cells needed for clinical trials. Here, ex vivo expansion and metabolism characters of CIK cells in static and dynamic cultures and the relationship between cell expansion and metabolism were investigated. Materials and methods Oxygen transfer efficiency was assessed by computational fluid dynamics technique. Cell phenotype, apoptosis and of transporter expression were determined by flow cytometry and Western blotting. Metabolites and enzyme activities were assessed by biochemical methods. Results Dynamic cultures favoured better CIK cell expansion without impairing their phenotype and cytotoxicity, enhanced oxygen transfer efficiency. The glucose metabolism flux of cells in dynamic cultures was enhanced by upregulating surface glucose transporter 1 expression and phosphofructokinase activity. Moreover, pentose phosphate pathway (PPP) metabolic flux was enhanced through upregulating glucose‐6‐phosphate dehydrogenase activity. Glutaminolysis was also accelerated via boosting glutamine transporters expression, glutaminase (GLS) and glutamate dehydrogenase activities. Together with higher oxygen consumption rate and extracellular acidification rate, it was suggested that cells in dynamic cultures were in a more vigorous metabolic state for ATP production. Conclusion Dynamic cultures accelerated glucose and glutamine metabolic flux to promote ATP production, elevated glucose metabolic flux through PPP to promote biosynthesis for better cell expansion. These findings may provide the basis for ex vivo CIK cell expansion process optimization.

Hematopoietic stem/progenitor cells (HSPCs) ex vivo expansion is critical in facilitating their widespread clinical application. NF-κB pathway is implicated in the energy homeostasis and metabolic adaptation. To explore the effect of NF-κB pathway on the ex vivo HSPC expansion and metabolism, the 50 nM–1 μM inhibitor of NF-κB pathway TPCA-1 was used to expand cord blood derived CD34+ cells in serum-free culture. The expansion folds, function, mitochondrial profile and metabolism of HSPCs were determined. After 10 days of culture with 100 nM TPCA-1, the expansion of total cells， CD34+CD38− cells， and CD34+CD38−CD45RA−CD90+CD49f+ cells were significantly increased compared to the cytokine priming alone. Notably, TPCA-1 treatment generated ~ 2-fold greater percentage of CD34+EPCR+ and CD34+CD38−CD45RA−CD90+CD49f+ cells compared to cytokine only conditions. Moreover, TPCA-1 expanded CD34+ cells displayed enhanced serial colonies forming potential and secondary expansion capability. NF-κB inhibition increased the expression of self-renewal related genes, while downregulated the expression of mitochondrial biogenesis regulator (Pgc1α) and mitochondrial chaperones and proteases (ClpP, Hsp10, Hsp60). Mitochondrial mass and membrane potential were markedly decreased with TPCA-1 treatment, leading to the reduced mitochondrial reactive oxygen species (ROS) level in HSPCs. NF-κB inhibition displayed augmented glycolysis rate with compromising mitochondrial metabolism. This study demonstrated that NF-κB pathway inhibition improved glycolysis and limited ROS production that promoted the ex vivo expansion and maintenance of functional HSPCs.

Methicillin-resistant Staphylococcus aureus (MRSA) has emerged as one of the most important pathogens both in health care and in community-onset infections. Cbf-K16, a cathelicidin-like antimicrobial peptide, presented broad antimicrobial activity during our previous studies. We evaluated the potential for synergy of Cbf-K16 with ceftazidime/ampicilin against MRSA, which was resistant to these two antibiotics with the minimum inhibitory concentration more than 64 μg/ml. The combinations showed a synergistic effect by a checkerboard assay with a fractional inhibitory concentration index ≤0.5. The killing curves of the combination treatment against MRSA showed that CFU counts decreased rapidly within 4 h by almost five logs, while single medication groups and the control group exhibited little inhibitory effect. In addition, in a mice bacteremia model, studies indicated that the combination treatment significantly prolonged the survival time of mice infected with MRSA, with a death protection rate of 80 %. Flow cytometry analysis and transmission electron microscopy indicated that combination-treated MRSA was completely ruptured with the cellular contents leaked out. The synergistic effect showed that Cbf-K16 selectively killed cells with non-integrity induced by cell wall inhibition antibiotics, suggesting that Cbf-K16 is a potential therapeutic agent and adjuvant for antimicrobial chemotherapy.

This study aimed to use floating photobioreactor (PBR) to produce microalgae biomass for aquaculture applications, and this was tested with cultivation of Isochrysis zhangjiangensis. The highest cell density of 16.1 ± 0.61 × 106 cell L–1 was obtained in an outdoor culture with a depth of 5.0 cm in 1.0 m2 floating PBR, but deeper culture resulted in higher biomass productivity. Large-scale cultivation at size of 10 m2 (1000 L) produced the highest cell density of 17.8 × 106 cell L–1 and highest biomass productivity of 0.115 g L–1 d–1, which was at the same level as that for flat-panel PBR (100 L). This developed technique provides an innovative approach to produce microalgae on site for use as fresh aquaculture feed, as well as fresh cells for use as seed inoculums for large-area aquaculture water bodies. This approach provides not only a low-cost microalgae production system but also better integration between microalgae production and aquaculture.

The insulin-like growth factor-2 mRNA-binding protein 1 (IGF2BP1) plays essential roles in embryogenesis and carcinogenesis. IGF2BP1 serves as a post-transcriptional fine-tuner regulating the expression of some essential mRNA targets required for the control of tumor cell proliferation and growth, invasion, and chemo-resistance, associating with a poor overall survival and metastasis in various types of human cancers. Therefore, IGF2BP1 has been traditionally regarded as an oncogene and potential therapeutic target for cancers. Nevertheless, a few studies have also demonstrated its tumor-suppressive role. However, the details about the contradictory functions of IGF2BP1 are unclear. The growing numbers of microRNAs (miRNAs) and long non-coding RNAs (lncRNAs) have been identified as its direct regulators, during tumor cell proliferation, growth, and invasion in multiple cancers. Thus, the mechanisms of post-transcriptional modulation of gene expression mediated by IGF2BP1, miRNAs, and lncRNAs in determining the fate of the development of tissues and organs, as well as tumorigenesis, need to be elucidated. In this review, we summarized the tissue distribution, expression, and roles of IGF2BP1 in embryogenesis and tumorigenesis, and focused on modulation of the interconnectivity between IGF2BP1 and its targeted mRNAs or non-coding RNAs (ncRNAs). The potential use of inhibitors of IGF2BP1 and its related pathways in cancer therapy was also discussed.

Intracellular reactive oxygen species (ROS) play important roles in the ex vivo expansion of hematopoietic stem and progenitor cells (HSPCs). In this study, the effects of resveratrol (RES), on the ex vivo expansion of HSPCs were investigated by analyzing CD34

Thermosensitive poly(N-isopropylacrylamide) (PNIPAM)-based substrates have presented great promise in cell sheet engineering. However, non-functionalized PNIPAM cannot be well applied for cell cultivation, due to the low cell adhesion. Herein, to enhance PNIPAM-based substrates and to promote cell proliferation and detachment, a polyhedral oligomeric silsesquioxane (POSS) nanoscale inorganic enhanced agent has been introduced into PNIPAM matrices to construct POSS-containing hybrid hydrogels. The hydrogels were facilely prepared using POSS as a cross-linker via one-pot crosslinking reaction under UV irradiation. The swelling behavior, thermal stability and the mechanical properties of POSS–PNIPAM hybrid hydrogels have been evaluated and they are all dependent on the content of POSS. The in vitro experiment confirms that human amniotic mesenchymal stem cells (hAMSCs) exhibit clearly enhanced adhesion and proliferation on the substrates of POSS–PNIPAM hybrid hydrogels in comparison to the pure PNIPAM hydrogel without POSS. Based on the thermal-responsiveness of PNIPAM, the proliferated cells are easily released without damage from the surface of hybrid hydrogels. Therefore, POSS-enhanced PNIPAM hybrid hydrogels provide a unique approach for harvesting anchorage dependent stem cells.

Poly(maleimide isobutyl polyhedral oligomeric silsesquioxane-alt-vinylbenzyl polyethylene glycol) (P(MIPOSS-alt-VBPEG)) amphiphilic copolymer brushes with a sequence of alternating MIPOSS and polyethylene glycol (PEG) side chains were synthesized via ordinary radical polymerization and reversible addition–fragmentation transfer (RAFT) polymerization. A series of alternating copolymer brushes prepared by RAFT polymerization had a low polydispersity index (PDI) of less than 1.25. The thermal properties of these copolymers were evaluated by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The results displayed that the MIPOSS units could effectively enhance the thermal properties of the hybrid copolymers. The self-assembly behavior of the P(MIPOSS-alt-VBPEG) amphiphilic copolymer brushes in aqueous media was also studied by fluorescence spectrophotometry (FS), transmission electron microscopy (TEM) and dynamic light scattering (DLS). The results showed that these alternating copolymer brushes could form spherical aggregates in water.

Amphiphilic PNIPAM-b-PTPPC6MA block copolymers were first synthesized using porphyrin-containing monomers. The mono-hydroxylphenyl-triphenylporphyrin photosensitizer, TPP-OH, was modified into a porphyrin monomer, and it was further used to construct the amphiphilic PNIPAM-b-PTPPC6MA block copolymers using RAFT polymerization. PNIPAM-b-PTPPC6MA block copolymers can self-assemble into a plethora of morphologies ranging from spheres to vesicular aggregates and further to a single large vesicle. The PNIPAM-b-PTPPC6MA micelles exhibited a high singlet oxygen quantum yield. Moreover, confocal laser scanning microscopy (CLSM) and flow cytometry analysis confirmed that PNIPAM-b-PTPPC6MA micelles could effectively enhance the internalization rate in MCF-7 cells. According to the MTT assay, PNIPAM-b-PTPPC6MA micelles exhibited low dark toxicity and efficient PDT efficacy towards MCF-7 cells. Thus PNIPAM-b-PTPPC6MA block copolymers have the potential application for photodynamic therapy.

Ex vivo expansion of hematopoietic stem cells (HSCs) with most current methods can hardly satisfy clinical application requirement. While in vivo, HSCs efficiently self-renew in niche where they interact with 3D extracellular matrix and stromal cells. Therefore, co-cultures of CD34

Ex-vivo expansion technologies were developed for application of hematopoietic stem cells (HSCs) derived from cord blood (CB). The cytokine combination was essential to expand HSCs ex vivo and maintain the function of expanded HSCs. However the optimal cytokine combination was not determined. In this study, two combinations of cytokines were applied in ex-vivo expansion of HSCs to investigate the effect on the hematopoietic repopulating ability of expanded HSCs. CB CD34(+) cells were expanded with SCF + TPO + FL (STF) or SCF + TPO + FL + IL-3 + IL-6 (STF36) for 7 days and got 30.3 ± 6.4 and 39.8 ± 7.3 folds of total cells, respectively. The cells cultured by both STF and STF36 could engraft and repopulate in non-obese diabetic/severe combined immunodeficiency (NOD/SCID) mice effectively; however, the STF group achieved higher level of engraftment. These result demonstrated that the cytokine combination of STF36 favored the expansion of cells, while the cytokine combination of STF facilitated the engraftment and multi-lineage repopulating in vivo. These findings may have important implications for the cell therapy.