Alpha-synuclein dynamics bridge Type-I Interferon response and SARS-CoV-2 replication in peripheral cells

Background Increasing evidence suggests a double-faceted role of alpha-synuclein (α-syn) following infection by a variety of viruses, including SARS-CoV-2. Although α-syn accumulation is known to contribute to cell toxicity and the development and/or exacerbation of neuropathological manifestations, it is also a key to sustaining anti-viral innate immunity. Consistently with α-syn aggregation as a hallmark of Parkinson's disease, most studies investigating the biological function of α-syn focused on neural cells, while reports on the role of α-syn in periphery are limited, especially in SARS-CoV-2 infection. Results Results herein obtained by real time qPCR, immunofluorescence and western blot indicate that α-syn upregulation in peripheral cells occurs as a Type-I Interferon (IFN)-related response against SARS-CoV-2 infection. Noteworthy, this effect mostly involves α-syn multimers, and the dynamic α-syn multimer:monomer ratio. Administration of excess α-syn monomers promoted SARS-CoV-2 replication along with downregulation of IFN-Stimulated Genes (ISGs) in epithelial lung cells, which was associated with reduced α-syn multimers and α-syn multimer:monomer ratio. These effects were prevented by combined administration of IFN-β, which hindered virus replication and upregulated ISGs, meanwhile increasing both α-syn multimers and α-syn multimer:monomer ratio in the absence of cell toxicity. Finally, in endothelial cells displaying abortive SARS-CoV-2 replication, α-syn multimers, and multimer:monomer ratio were not reduced following exposure to the virus and exogenous α-syn, suggesting that only productive viral infection impairs α-syn multimerization and multimer:monomer equilibrium. Conclusions Our study provides novel insights into the biology of α-syn, showing that its dynamic conformations are implicated in the innate immune response against SARS-CoV-2 infection in peripheral cells. In particular, our results suggest that promotion of non-toxic α-syn multimers likely occurs as a Type-I IFN-related biological response which partakes in the suppression of viral replication. Further studies are needed to replicate our findings in neuronal cells as well as animal models, and to ascertain the nature of such α-syn conformations.

Isolation of bone marrow mesenchymal stem cells in transgenic pigs and co-culture with porcine islets / 器官移植

Objective To investigate the isolation and culture of porcine bone marrow mesenchymal stem cell (BMSC) with α-1, 3-galactosyltransferase (GGTA1) gene knockout (GTKO), GTKO/ human CD46 (hCD46) insertion and cytidine monopho-N-acetylneuraminic acid hydroxylase (CMAH)/GGTA1 gene knockout (Neu5GC/Gal), and the protective effect of co-culture with porcine islets on islet cells. Methods Bone marrow was extracted from different transgenic pigs modified with GTKO, GTKO/hCD46 and Neu5GC/Gal. Porcine BMSC were isolated by the whole bone marrow adherent method and then cultured. The morphology of BMSC was observed and the surface markers of BMSC were identified by flow cytometry. Meantime, the multi-directional differentiation induced by BMSC was observed, and the labeling and tracing of BMSC were realized by green fluorescent protein (GFP) transfection. The porcine BMSC transfected with GFP were co-cultured with porcine islet cells. Morphological changes of porcine islet cells were observed, and compared with those in the porcine islet cell alone culture group. Results BMSC derived from pigs were spindle-shaped in vitro, expressing biomarkers of CD29, CD44, CD73, CD90, CD105 and CD166 rather than CD34 and CD45. These cells were able to differentiate into adipocytes, osteoblasts and chondrocytes. Porcine BMSC with GFP transfection could be labeled and traced, which could be stably expressed in the daughter cells after cell division. Porcine BMSC exerted certain protective effect on islet cells. Conclusions GFP-labeled porcine BMSC modified with GTKO, GTKO/hCD46 and Neu5GC/Gal are successfully established, which exert certain protective effect upon islet cells.

Detection of Calreticulin as a Candidate Prognostic Biomarker in Invasive Breast Carcinoma from a Biological Scaffold-Based 3D Co-culture System

@#Introduction: Breast cancer is the most common cancer in women and the world’s second leading cause of death in women, after lung cancer. Calreticulin (CRT), an endoplasmic reticulum (ER) multipurpose protein, has been proposed as a potential biomarker for breast cancer. However, reports on the correlation between CRT expression and cell invasiveness in breast cancer micro-tissues are scarce. Thus, in the current study, we analyzed the potential correlation between CRT and invasiveness of breast cancer in a biological scaffold-based 3D co-culture system. Methods: MCF7, MDA-MB-231 and MCF-10A breast cell lines were co-cultured in a 3-dimensional (3D) system with MRC-5 lung fibroblast cell line in the cell density ratio of 3:1. Thereafter, calreticulin gene and protein expression levels were determined based on quantitative reverse transcription-polymerase chain reaction (RT-qPCR) and immunohistochemistry, respectively. Moreover, via RT-qPCR analysis, the gene expression levels of calreticulin-related candidate metastasis genes in breast cancer micro-tissues were carried out. Results: The results showed occasional foci of lumen-like morphology in the non-cancerous breast micro-tissues and the formation of solid clusters for breast cancer micro-tissues. Moreover, immunohistochemistry results revealed protein expression of calreticulin in non-cancerous and cancerous breast micro-tissues with cytoplasmic and nucleic acid localizations. It was found that PCMT1 and ER-α genes were significantly downregulated (p < 0.01) in invasive breast cancer micro-tissues. Conclusion: This study suggests that CRT and CRT-related candidate metastasis genes may potentially serve as prognostic biomarkers in invasive breast carcinoma.

Structural diversification of bioactive bibenzyls through modular co-culture leading to the discovery of a novel neuroprotective agent

Bibenzyls, a kind of important plant polyphenols, have attracted growing attention for their broad and remarkable pharmacological activities. However, due to the low abundance in nature, uncontrollable and environmentally unfriendly chemical synthesis processes, these compounds are not readily accessible. Herein, one high-yield bibenzyl backbone-producing Escherichia coli strain was constructed by using a highly active and substrate-promiscuous bibenzyl synthase identified from Dendrobium officinale in combination with starter and extender biosynthetic enzymes. Three types of efficiently post-modifying modular strains were engineered by employing methyltransferases, prenyltransferase, and glycosyltransferase with high activity and substrate tolerance together with their corresponding donor biosynthetic modules. Structurally different bibenzyl derivatives were tandemly and/or divergently synthesized by co-culture engineering in various combination modes. Especially, a prenylated bibenzyl derivative ( 12) was found to be an antioxidant that exhibited potent neuroprotective activity in the cellular and rat models of ischemia stroke. RNA-seq, quantitative RT-PCR, and Western-blot analysis demonstrated that 12 could up-regulate the expression level of an apoptosis-inducing factor, mitochondria associated 3 (Aifm3), suggesting that Aifm3 might be a new target in ischemic stroke therapy. This study provides a flexible plug-and-play strategy for the easy-to-implement synthesis of structurally diverse bibenzyls through a modular co-culture engineering pipeline for drug discovery.

iPSCs ameliorate hypoxia-induced autophagy and atrophy in C2C12 myotubes via the AMPK/ULK1 pathway

Background Duchenne muscular dystrophy (DMD) is an X-linked lethal genetic disorder for which there is no effective treatment. Previous studies have shown that stem cell transplantation into mdx mice can promote muscle regeneration and improve muscle function, however, the specific molecular mechanisms remain unclear. DMD suffers varying degrees of hypoxic damage during disease progression. This study aimed to investigate whether induced pluripotent stem cells (iPSCs) have protective effects against hypoxia-induced skeletal muscle injury. Results In this study, we co-cultured iPSCs with C2C12 myoblasts using a Transwell nested system and placed them in a DG250 anaerobic workstation for oxygen deprivation for 24 h. We found that iPSCs reduced the levels of lactate dehydrogenase and reactive oxygen species and downregulated the mRNA and protein levels of BAX/BCL2 and LC3II/ LC3I in hypoxia-induced C2C12 myoblasts. Meanwhile, iPSCs decreased the mRNA and protein levels of atrogin-1 and MuRF-1 and increased myotube width. Furthermore, iPSCs downregulated the phosphorylation of AMPKA and ULK1 in C2C12 myotubes exposed to hypoxic damage. Conclusions Our study showed that iPSCs enhanced the resistance of C2C12 myoblasts to hypoxia and inhibited apoptosis and autophagy in the presence of oxidative stress. Further, iPSCs improved hypoxia-induced autophagy and atrophy of C2C12 myotubes through the AMPK/ULK1 pathway. This study may provide a new theoretical basis for the treatment of muscular dystrophy in stem cells.

Identification of the metabolites from co-cultures of marine Streptomyces sp. IMB18-531 and Cladosporium sp. IMB19-099 / 药学学报

A new siderophore chelate (1) and 8 known compounds were identified from the liquid co-cultures of the marine-derived Streptomyces sp. IMB18-531 and Cladosporium sp. IMB19-099 by a combination of chromatography methods, including C18 reversed-phase medium pressure chromatography, gel column chromatography and HPLC. Their structures were determined by spectroscopic analysis and chemical methods as aluminioxamine E (1), desferrioxamine E (2), ferrioxamine E (3), terragine E (4), capsimicin (5), cyclo(L-prolinyl-L-tyrosine) (6), anthranilic acid (7), (Z)-14-methylpentadec-9-enoic acid (8), and (Z)-hexadec-8-enoic acid (9). Compound 2 showed inhibitory activities against the expression of liver fibrosis related genes COL1A1, MMP2, and TIMP2. Compounds 5, 8, and 9 displayed antibacterial activities against methicillin-resistant Staphylococcus aureus, S. epidermidis and Bacillus subtilis, with MICs of 16-64 μg·mL-1. Compound 5 showed cytotoxicities against human pancreatic cancer MIA Paca-2 and human colon cancer HT-29 cell lines with IC50 of 2.9 and 6.3 μmol·L-1, respectively.

Effect of Angelica dahurica coumarins on the transport behavior of puerarin across blood-brain barrier in vitro and in vivo / 药学学报

A BBB co-culture cell model consisting of rat brain microvascular endothelial cells (BMEC) and astrocytes (AS) was established to study the effect of Angelica dahurica coumarins on the transport behavior of puerarin across blood-brain barrier (BBB) in vitro and in vivo. The barrier function of this model was evaluated by measuring the transendothelial resistance, phenol red permeability and BBB related protein expression. The permeability assay and western blot methods were performed to study the effects of Angelica dahurica coumarins on the BBB permeability and the expression of BBB related protein. The animal experiment protocols in this study were approved by the Animal Ethics Committee of Xi'an Jiaotong University (Animal Ethics No.: 2021-1329). The results showed that the established BMEC/AS co-culture model could be used to evaluate drug transport across BBB in vitro. After combined with Angelica dahurica coumarins, the transport capacity of puerarin was significantly increased in vitro and in vivo. Additionally, Angelica dahurica coumarins enhanced BBB permeability and inhibited the protein expression of P-glycoprotein (P-gp), zonula occludens-1 (ZO-1) and occludin. Angelica dahurica coumarins might increase BBB permeability by inhibiting the expression of P-gp and tight junction protein, thereby increasing the content of puerarin in brain tissue.

Application progress of air-liquid interface exposure technology in respiratory system toxicity induced by diesel exhaust in vitro / 环境与职业医学

Diesel exhaust (DE) is an important pollution source widely existing in the living and production environment, which is closely related to the health of the public and occupational groups. The International Agency for Research on Cancer has classified DE as a Group 1 carcinogen. Considering the negative health impacts on the respiratory system due to DE exposure in vitro, it is crucial to apply reliable test systems allowing accurate assessment of the biological effects of DE. The exposure technology of respiratory system in vitro is considered as one of the feasible measures to implement the 3R (reduce, refine, and replace) principle in animal experiments. Compared with the traditional submerged culture in vitro models, the air-liquid interface (ALI) exposure technology has the advantages including fewer influencing factors, easier exposure condition control, and shorter exposure cycle. ALI has become an important tool to study molecular events associated with physiology and pathology of respiratory system, and action modes and interactions of different cell types. Also, ALI has been increasingly widely used because it can simulate the actual processes of human respiratory system cells and/or tissues to DE exposure. This review was intended to introduce the development and advantages of ALI exposure technology, and further summarized the application progress of ALI exposure technology in studying the respiratory toxicity induced by DE exposure in vitro, so as to provide new ideas and pathways for the use of ALI exposure technology in the study of biomarkers and mechanisms of respiratory toxicity associated with DE exposure, and provide basic data to screen and promote biomarkers for exposed populations.

Progress in antitumor effect of tumor-associated macrophages in co-culture system / 中华微生物学和免疫学杂志

Macrophages are important cells of the immune system. Tumor-associated macrophages are enriched macrophages near tumor cells or tissues. Their role is mainly to promote the construction of tumor inflammatory microenvironment and inhibit tumor immune response. Cell co-culture system is a symbiotic culture system formed by mimicking the internal environment of the body in vitro. The co-culture condition is relatively consistent with the environment in vivo, enabling better information exchange and material exchange between cells, which is a supplement to the monolayer cell culture and animal experiments. Tumor-associated macrophages and tumor cells co-exist in the tumor microenvironment. Thus, constructing a co-culture system for tumor-associated macrophages and tumor cells would be conducive to studying the antitumor effect of tumor-associated macrophages and developing new immunotherapy drugs. The co-culture system would provide a new direction for treating malignant tumors. This article mainly reviewed the co-culture patterns of macrophages and the antitumor effects of different phenotypes of macrophages, and highlighted the importance of using immunotherapy to treat malignant tumors in the tumor microenvironment.

A study on keloid fibroblast induced THP-1 derived macrophage polarization and inflammatory factor TNF-αexpression and its feedback effect / 中华医学美学美容杂志

Objective:To investigate the effect of keloid fibroblasts on the polarization and expression of inflammatory factors of M0 macrophages and possible mechanisms, and provide theoretical basis for new targets for keloid therapy.Methods:Keloids, normal skin tissues and paraffin specimens from patients undergoing plastic surgery in the First Affiliated Hospital of Sun Yat-sen University from November 2020 to September 2021 were collected, and fibroblasts of keloids and normal skins were isolated and co-cultured with M0 cells formed form THP-1 by phorbol ester (PMA)-stimulation to detect the expression of macrophage polarization markers and cytokines. Besides, keloid fibroblasts were treated with exogenous tumor necrosis factor-α(TNF-α) to detect its effect on the proliferation and extracellular matrix expression.Results:Macrophages were dominated by CD163 + (M2) in keloid tissues. Moreover, M0 cells expressed more TNF-α when co-cultured with keloid fibroblasts, compared with those with normal skin fibroblasts, in which, the positive staining rates of TNF-α were 19.32% and 29.52% respectively by flow cytometry. Furthermore, the proliferation was promoted and the expression of extracellular matrix proteins (COL3A1 and FN1)and Vimentin were upregulated in keloid fibroblasts under TNF-α stimulation. However, there was no significant difference in the expression of polarization surface markers CD86 and CD163 in macrophages, when co-cultured with keloid fibroblasts or normal skin fibroblasts. Conclusions:Keloid fibroblasts promote the expression of TNF-α in macrophages, which in turn promotes the proliferation and extracellular matrix secretion of keloid fibroblasts.

Application and population control strategy of microbial modular co-culture engineering / 生物工程学报

Traditional methods of microbial synthesis usually rely on a single engineered strain to synthesize the target product through metabolic engineering. The key cofactors, precursors and energy are produced by the introduced complex synthetic pathways. This would increase the physiological burden of engineering strains, resulting in a decrease in the yield of target products. The modular co-culture engineering has become an attractive solution for effective heterologous biosynthesis, where product yield can be greatly improved. In the modular co-culture engineering, the coordination between the population of different modules is essential for increasing the production efficiency. This article summarized recent advances in the application of modular co-culture engineering and population control strategies.

Advances in the co-culture of microalgae with other microorganisms and applications / 生物工程学报

Intense utilization and mining of fossil fuels for energy production have resulted in environmental pollution and climate change. Compared to fossil fuels, microalgae is considered as a promising candidate for biodiesel production due to its fast growth rate, high lipid content and no occupying arable land. However, monocultural microalgae bear high cost of harvesting, and are prone to contamination, making them incompetent compared with traditional renewable energy sources. Co-culture system induces self-flocculation, which may reduce the cost of microalgae harvesting and the possibility of contamination. In addition, the productivity of lipid and high-value by-products are higher in co-culture system. Therefore, co-culture system represents an economic, energy saving, and efficient technology. This review aims to highlight the advances in the co-culture system, including the mechanisms of interactions between microalgae and other microorganisms, the factors affecting the lipid production of co-culture, and the potential applications of co-culture system. Finally, the prospects and challenges to algal co-culture systems were also discussed.

Using OMICS technologies to analyze the mechanisms of synthetic microbial co-culture systems: a review / 生物工程学报

In recent years, the interaction mechanisms underpinning the synthetic microbial co-culture systems have gained increasing attention due to their potentials in various biotechnological applications. Exploration of the inter-species mechanisms underpinning the synthetic microbial co-culture system could contribute to a better understanding of the theoretical basis to further optimize the existing co-culture systems, and design new synthetic co-culture system for large-scale application. OMICS technologies such as genomics, transcriptomics, proteomics, and metabolomics could analyze the biological processes in a high throughput manner. Multi-omics analysis could achieve a "global view" of various members in the microbial co-culture systems, which presents opportunities in understanding synthetic microbial consortia better. This article summarizes recent advances in understanding the mechanisms of synthetic microbial co-culture systems using omics technologies, from the aspects of metabolic network, energy metabolism, signal transduction, membrane transport, stress response, community stability and structural rationality. All these findings could provide important theoretical basis for future application of the microbial co-culture systems with the aids of emerging biotechnologies such as synthetic biology and genome editing.

Co-cultured adventitious roots of Echinacea pallida and Echinacea purpurea inhibit lipopolysaccharide-induced inflammation via MAPK pathway in mouse peritoneal macrophages / 中草药·英文版

Objective: In order to elucidate the biological activity of the co-cultured adventitious roots (ARs) of Echinacea pallida and Echinacea purpurea and provide theoretical basis for its application, and the anti-inflammatory activities and potential mechanisms of co-cultured ARs were studied. Methods: The experimental materials were obtained by bioreactor co-culture technology and used in the activity research. In this study, mouse macrophages induced by lipopolysaccharide (LPS) were used as in vitro model. Different concentrations of AR extract (50–400 g/mL) were used to treat cells. The expression of pro-inflammatory cytokines was determined using enzyme linked immunosorbent assay. The inducible nitric oxide synthase and cyclooxygenase-2 expression, mitogen-activated protein kinase (MAPK) phosphorylation, and the inhibitor of nuclear factor-kappa B-α levels were determined by the Western blot analysis. Results: In the co-cultured ARs, total flavonoids and total caffeic acid were determined, and the contents of both bioactive compounds were significantly higher than those ARs from the single-species culture. Compared with the control group, the large amount of pro-inflammatory mediators was released after LPS stimulation. However, in the extract groups with different concentrations (25, 50, and 100 g/mL), the production of these pro-inflammatory mediators was inhibited in a dose-dependent manner. Furthermore, the levels of phosphorylation of MAPK proteins, including p-p38, p-c-Jun N-terminal kinase, and p-extracellular regulated protein kinases were significantly (P < 0.05) decreased in the extract groups, revealing that the AR extract probably involved in regulating the MAPK signaling pathway. Conclusion: Collectively, our findings suggested that the co-cultured ARs of E. pallida and E. purpurea can inhibit production of pro-inflammatory mediators in mouse peritoneal macrophages and possess the anti-inflammatory effect by regulating MAPK signaling pathways.

Metformin alleviates intestinal epithelial barrier damage by inhibiting endoplasmic reticulum stress-induced cell apoptosis in colitis cell model / 浙江大学学报·医学版

To investigate the effect and mechanism of metformin on intestinal epithelial barrier injury in ulcerative colitis. A cell model of colitis was established by co-culture of human colon cancer cell line Caco-2 and human monocyte cell line THP-1. The colitis model cells were treated with metformin at concentration of for Flow cytometry was used to detect Caco-2 cell apoptosis, and Western blotting was used to detect the protein expression of tight junction proteins and endoplasmic reticulum stress-related proteins. After metformin treatment, the apoptosis rate of Caco-2 cells was decreased from (14.22±2.34)% to 0.61)% (=3.119, <0.05), and the expression levels of tight junction protein-1 and claudin-1 increased (=5.172 and 3.546, both <0.05). In addition, the expression levels of endoplasmic reticulum-related proteins glucose regulated protein (GRP) 78, C/EBP homologous protein (CHOP) and caspase-12, as well as the phosphorylation level of PRKR-like endoplasmic reticulum kinase (PERK) and eukaryotic translation initiation factor 2α (eIF2α) decreased (all <0.05). Metformin may alleviate the intestinal epithelial barrier damage in colitis by reducing intestinal epithelial cell apoptosis and increasing the expression of tight junction proteins, which may be associated with the inhibition of endoplasmic reticulum stress-induced apoptotic pathway.

Induction and differentiation of induced pluripotent stem cells into macrophages: a review / 生物工程学报

Induced pluripotent stem cells (iPSCs) are a type of cells similar to embryonic stem cells but produced by reprogramed somatic cells. Through in vitro differentiation of iPSCs, we can interrogate the evolution history as well as the various characteristics of macrophages. iPSCs derived macrophages are not only a good model for drug screening, but also an important approach for immunotherapy. This review summarizes the advances, challenges, and future directions in the field of iPSCs-derived macrophages.

Co-culture of Neural Stem Cells and Spinal Cord Acellular Scaffold in Vitro / 中国康复理论与实践

Objective:To observe the adhesion, growth and differentiation of rat neural stem cells (NSCs) on spinal cord acellular scaffold (SCAS) to evaluate its feasibility for spinal cord tissue engineering. Methods:NSCs derived from neonatal Sprague-Dawley rat cerebral cortex were cultured and identified. SCAS were prepared from female Sprague-Dawley rat spinal cord tissues using modified chemical extraction and physical oscillation, and evaluated. The third generation NSCs were planted on SCAS and co-cultured, the morphology of the cells on the scaffold was observed with immunofluorescence, immunohistochemistry and scanning electron microscope. Results:The cultured cells were NSCs, which could proliferate and differentiate. The porosity, water content and enzymatic hydrolysis rates of the prepared SCAS were significantly higher than that of normal spinal cord (|t| > 4.679, P < 0.01). The matrix structure of SCAS was loosely network-like, with few residual nuclei. NSCs adhered and grew well, and differentiated into neurons and glial cells on SCAS. Conclusion:This kind of SCAS shapes multi-channel spatial structure and is suitable for NSCs adhesion, growth and differentiation, which can be used for spinal cord tissue engineering.

Production of lactate from carbon fixation by cyanobacteria: development and prospect / 生物工程学报

Lactate is an important industrial chemical and widely used in various industries. In recent years, with the increasing demand for polylactic acid (PLA), the demand for lactate raw materials is also increasing. The contradiction between the high cost and the market demand caused by the heterotrophic production of lactate attracts researchers to seek other favorable solutions. The production of lactate from photosynthetic carbon fixation by cyanobacteria is a potential new raw material supply strategy. Based on the photosynthetic autotrophic cell factory, it can directly produce high optical purity lactate from carbon dioxide on a single platform driven by solar energy. The raw materials are cheap and easy to obtain, the process is simple and controllable, the products are clear and easy to separate, and the double effects of energy saving and emission reduction and production of high value-added products are achieved at the same time, which has important research and application value. This paper reviews the development history of cyanobacteria carbon sequestration to produce lactate, summarizes its research progress and encounters technical difficulties from the aspects of metabolic basis, metabolic engineering strategy, metabolic kinetics analysis and technical application, and prospects the future of this technology.

Supporting effect of human skeletal muscle-derived myoendothelial cells on hematopoietic stem/progenitor cells in vitro / 中国组织工程研究

BACKGROUND: Human skeletal muscle derived myoendothelial cells (MECs) are located in the vascular wall and co-express the markers of muscle stem cells and vascular endothelial cells (CD56+CD34+CD144+CD45-). Studies have shown that MECs are similar to mesenchymal stem cells, express the surface markers of mesenchymal stem cells and have the potential of multidirectional differentiation. OBJECTIVE: To establish an in vitro culture system for human umbilical cord blood CD34+ cells with MECs as trophoblastic layer, and to evaluate the in vitro supporting effect of human skeletal muscle MECs on hematopoietic stem/progenitor cells by measuring the changes in the number, immunophenotype and colony forming ability of CD34+ cells before and after culture. METHODS: There were three groups in the experiment. In experimental group, human umbilical cord blood CD34+ cells were co-cultured with MECs as the nourishing layer; in control group, human umbilical cord blood CD34+ cells were co-cultured with bone marrow mesenchymal stem cells as the nourishing layer; and in blank control group, human umbilical cord blood CD34+ cells were cultured alone without the nourishing layer. The main outcome measures, including the number of human umbilical cord blood CD34+ cells, immunophenotype of blood cells and colony formation ability of hematopoietic stem/progenitor cells were analyzed and compared at 1, 2, and 4 weeks after co-culture. No detection was conducted at 5 weeks due to the lack of survived cells. RESULTS AND CONCLUSION: (1) The number of human umbilical cord blood CD34+ cells increased by MECs as the nourishing layer compared with bone marrow mesenchymal stem cells as the nourishing layer at 1, 2, and 4 weeks; however, there was no significant difference between the two groups (P > 0.05). (2) The cell immunophenotype by flow cytometry analysis indicated that only in the 2nd week, the expression of CD34+CD33- in human umbilical cord blood CD34+ cells in the control group was significantly higher in the experimental group (P 0.05). (3) The colony formation capacity of hematopoietic stem/progenitor cells showed no significant difference between the experimental and control groups at 1, 2, and 4 weeks (P > 0.05). (4) Due to the non-nourishing layer culture system, the number of human umbilical cord blood CD34+ cells decreased significantly in the 1st week, and no cells survived in the 2nd week. Therefore, blood cell immunophenotype and colony analysis could not be performed. (5) To conclude, human skeletal muscle MECs as trophoblasts are the same as human bone marrow mesenchymal stem cells, which have a hematopoietic support in vitro.

Role and potential of adipose-derived stem cells in cranio-maxillofacial bone regeneration / 中国组织工程研究

BACKGROUND: The repair of cranio-maxillofacial bone defects is still facing severe challenges, and the introduction of the concept of bone regeneration points out a new direction for this problem. Adipose-derived stem cells are easy to access and have strong osteogenic differentiation capacity, which are considered as ideal seed cells for cranio-maxillofacial bone regeneration. OBJECTIVE: To review the influencing factors of osteogenic differentiation of adipose-derived stem cells as well as the research progress in cranio-maxillofacial bone regeneration, thus providing ideas for further study on adipose-derived stem cells in promoting cranio-maxillofacial bone regeneration. METHODS: A computer-based online search of PubMed, Wanfang, and CNKI databases was performed to retrieve papers published from January 2013 to February 2020 with the search terms of “adipose-derived stem cells, cranio-maxillofacial, oral tissue regeneration, periodontal tissue regeneration, bone regeneration, bone defects, osteogenesis” in English and Chinese. Finally, 88 papers were included for summary. RESULTS AND CONCLUSION: Adipose-derived stem cells can be induced to differentiate to osteoblasts and are easy to acquire in large quantities. It has a strong ability of expansion in vitro and has a broad application prospect in the field of cranio-maxillofacial bone regeneration. miRNAs/microRNAs play a role in the osteogenic differentiation of adipose-derived stem cells. The osteogenic differentiation ability of adipose-derived stem cells can be improved by the means of co-culture with other cells, combined with platelet-rich plasma or modified titanium and gene technology. Compared with conventional extracorporeal scaffolds, adipose-derived stem cells combined with injectable scaffolds have greater potential in osteogenesis. Some progress has been made in repairing cranio-maxillofacial bone defects with adipose-derived stem cells, but there is still a lack of sufficient evidence in large-scale clinical trials.