In vivo immunological properties research on mesenchymal stem cells based engineering cartilage by a dialyzer pocket model.

As the seed cells, the immune properties of the mesenchymal stem cells are important for the tissue engineering restoring effect. But the in vivo research model is lacking. In the study, based on a dialyzer pocket model, changes in immunological properties and the differentiation of seeded mesenchymal stem cells (MSCs) in collagen hydrogel were studied in muscle and articular cavity implantation, respectively. The results showed that collagen hydrogel can induce MSCs to form cartilage tissue, followed by alteration of immunological properties. In muscle implantation, relatively low expression of major histocompatibility complex (MHC) molecules and low level of one-way mixed lymphocyte reactions (MLR) on the seeded MSCs were observed, but only a little cartilage tissue formed. In articular cavity implantation, more cartilage tissue formed, but higher MHC expressions and MLR level were found. Results indicated that the immunomodulation and the cartilage formation of the seeded MSCs will be impacted by the scaffold and the environment of the in vivo implanted site. The dialyzer pocket model can be used for the in vivo research for the MSC-based strategy of the tissue engineering, especially for the optimization of the immunomodulation.

Covered versus uncovered self-expandable metallic stents for palliation of malignant gastric outlet obstruction: a systematic review and meta-analysis.

BACKGROUND: Self-expandable metallic stents (SEMSs) are widely used for palliation of malignant gastric outlet obstruction (GOO). There are two types of SEMS, covered and uncovered, each with its own advantages and disadvantages. We aimed to compare the efficacy and safety between uncovered and covered SEMSs in the palliation of malignant gastric outlet obstruction. METHODS: Databases including PubMed, EMBASE, the Cochrane Library, the Science Citation Index and momentous meeting abstracts were searched and evaluated by two reviewers independently. RESULTS: Nine trials involving 849 patients were analyzed. Meta-analysis showed there was no significant difference in technical success rate (RR 1.0, 95% CI [0.98, 1.01]), clinical success rate (RR 1.04, 95% CI [0.98, 1.11]), post-stenting dysphagia score (WMD -0.01, 95% CI [-0.52, 0.50]), stent patency (WMD -0.31, 95% CI [-1.73, 1.11]), overall complications (RR 1.07, 95% CI [0.87, 1.32]) and reintervention rate (RR 1.30, 95% CI [0.92, 1.83]) between covered and uncovered SEMSs group. However, covered SEMSs were associated with higher migration rate (RR 3.48, 95% CI [2.16, 5.62], P < 0.00001) and lower obstruction rate (RR 0.42, 95% CI [0.24, 0.73], P = 0.002). CONCLUSIONS: In the palliative treatment of malignant gastric outlet obstruction, both covered and uncovered SEMSs are safely and effective. Covered stents can reduce the risk of restenosis, whereas uncovered stents are effective in decreasing stent migration.

Success rate of current human-derived gastric cancer organoids establishment and influencing factors: A systematic review and meta-analysis.

BACKGROUND: Human-derived gastric cancer organoids (GCOs) are widely used in gastric cancer research; however, the culture success rate is generally low. AIM: To explore the potential influencing factors, and the literature on successful culture rates of GCOs was reviewed using meta-analysis. METHODS: PubMed, Web of Science, and EMBASE were searched for studies. Two trained researchers selected the studies and extracted data. STATA 17.0 software was used for meta-analysis of the incidence of each outcome event. The adjusted Methodological Index for Non-Randomized Studies scale was used to assess the quality of the included studies. Funnel plots and Egger's test were used to detect publication bias. Subgroup analyses were conducted for sex, tissue source, histological classification, and the pathological tumor-node-metastasis (pTNM) cancer staging system. RESULTS: Eight studies with a pooled success rate of 66.6% were included. GCOs derived from women and men had success rates of 67% and 46.7%, respectively. GCOs from surgery or biopsy/endoscopic submucosal dissection showed success rates of 70.9% and 53.7%, respectively. GCOs of poorly-differentiated, moderately-differentiated and signet-ring cell cancer showed success rates of 64.6%, 31%, and 32.7%, respectively. GCOs with pTNM stages I-II and III-IV showed success rates of 38.3% and 65.2%, respectively. Y-27632 and non-Y-27632 use showed success rates of 58.2% and 70%, respectively. GCOs generated with collagenase were more successful than those constructed with Liberase TH and TrypLE (72.1% vs 71%, respectively). EDTA digestion showed a 50% lower success rate than other methods (P = 0.04). CONCLUSION: GCO establishment rate is low and varies by sex, tissue source, histological type, and pTNM stage. Omitting Y-27632, and using Liberase TH, TrypLE, or collagenase yields greater success than EDTA.

Bibliometrics analysis based on the Web of Science: Current trends and perspective of gastric organoid during 2010-2023.

BACKGROUND: Three-dimensional organoid culture systems have been established as a robust tool for elucidating mechanisms and performing drug efficacy testing. The use of gastric organoid models holds significant promise for advancing personalized medicine research. However, a comprehensive bibliometric review of this bur-geoning field has not yet been published. AIM: To analyze and understand the development, impact, and direction of gastric organoid research using bibliometric methods using data from the Web of Science Core Collection (WoSCC) database. METHODS: This analysis encompassed literature pertaining to gastric organoids published between 2010 and 2023, as indexed in the WoSCC. CiteSpace and VOSviewer were used to depict network maps illustrating collaborations among authors, institutions and keywords related to gastric organoid. Citation, co-citation, and burst analysis methodologies were applied to assess the impact and progress of research. RESULTS: A total of 656 relevant studies were evaluated. The majority of research was published in gastroenterology-focused journals. Globally, Yana Zavros, Hans Clevers, James M Wells, Sina Bartfeld, and Chen Zheng were the 5 most productive authors, while Hans Clevers, Huch Meritxell, Johan H van Es, Marc Van de Wetering, and Sato Toshiro were the foremost influential scientists in this area. Institutions from the University Medical Center Utrecht, Netherlands Institute for Developmental Biology (Utrecht), and University of Cincinnati (Cincinnati, OH, United States) made the most significant contributions. Currently, gastric organoids are used mainly in studies investigating gastric cancer (GC), Helicobacter pylori-infective gastritis, with a focus on the mechanisms of GC, and drug screening tests. CONCLUSION: Key focus areas of research using gastric organoids include unraveling disease mechanisms and enhancing drug screening techniques. Major contributions from renowned academic institutions highlight this field's dynamic growth.

Using a synthetic machinery to improve carbon yield with acetylphosphate as the core.

In microbial cell factory, CO2 release during acetyl-CoA production from pyruvate significantly decreases the carbon atom economy. Here, we construct and optimize a synthetic carbon conserving pathway named as Sedoheptulose-1,7-bisphosphatase Cycle with Trifunctional PhosphoKetolase (SCTPK) in Escherichia coli. This cycle relies on a generalist phosphoketolase Xfspk and converts glucose into the stoichiometric amounts of acetylphosphate (AcP). Furthermore, genetic circuits responding to AcP positively or negatively are created. Together with SCTPK, they constitute a gene-metabolic oscillator that regulates Xfspk and enzymes converting AcP into valuable chemicals in response to intracellular AcP level autonomously, allocating metabolic flux rationally and improving the carbon atom economy of bioconversion process. Using this synthetic machinery, mevalonate is produced with a yield higher than its native theoretical yield, and the highest titer and yield of 3-hydroxypropionate via malonyl-CoA pathway are achieved. This study provides a strategy for improving the carbon yield of microbial cell factories.

Functional injectable hydrogel with spatiotemporal sequential release for recruitment of endogenous stem cells and in situ cartilage regeneration.

Articular cartilage is refractory to self-healing due to the absence of vascular, nervous, and lymphatic systems, and its repair remains a clinical challenge. Tissue regeneration through in situ recruitment of stem cells via cell-free scaffolds is a promising alternative strategy. Herein, a kind of functional injectable hydrogel system (Col-Apt@KGN MPs), which is a collagen-based and microsphere-embedded cell-free scaffold, was designed to achieve spatiotemporal regulation of endogenous mesenchymal stem cells (MSCs) recruitment and their chondrogenic differentiation by respective release of aptamer 19S (Apt19S) and kartogenin (KGN). In vitro results confirmed that the Col-Apt@KGN MPs hydrogel had sequential release characteristics. Apt19S was rapidly released from the hydrogel within 6 days, while KGN was slowly released for 33 days via the degradation of poly(lactic-co-glycolic acid) (PLGA) microspheres. When cultured with MSCs, the Col-Apt@KGN MPs hydrogel supported the adhesion, proliferation, and chondrogenic differentiation of MSCs. In vivo results indicated that the Col-Apt@KGN MPs hydrogel effectively promoted the recruitment of endogenous MSCs in a rabbit full-thickness cartilage defect model; furthermore, the Col-Apt@KGN MPs hydrogel enhanced the secretion of cartilage specific extracellular matrix and achieved the reconstruction of subchondral bone. This study demonstrates that the Col-Apt@KGN MPs hydrogel possesses great potential in recruitment of endogenous stem cells and cartilage tissue regeneration.

Components and physical properties of hydrogels modulate inflammatory response and cartilage repair.

Collagen and hyaluronic acid are commonly applied in cartilage tissue engineering, yet there has been limited investigation into their inflammatory response, a crucial factor in articular cartilage repair. This study aimed to evaluate the impact of components and physical properties of hydrogels on inflammatory response and cartilage repair. Three kinds of hydrogels with comparable storage moduli at low frequencies were designed and fabricated, namely, methacrylic anhydride-modified hyaluronic acid hydrogel (HAMA), methacrylic anhydride-modified type I collagen hydrogel (CMA) and unmodified type I collagen hydrogel (Col). HAMA hydrogel was unfavorable for adhesion and spreading of BMSCs. Furthermore, HAMA hydrogel stimulated rapid migration and pro-inflammatory M1 polarization of macrophages, leading to persistent and intense inflammation, which was unfavorable for cartilage repair. CMA and Col hydrogels possessed the same component and facilitated the adhesion, spreading and proliferation of BMSCs. Compared with CMA hydrogel, Col hydrogel induced rapid migration and moderate M1 polarization of macrophages at the early stage of injury, which was mainly influenced by its fast dissolution rate, small pore size fiber network structure and rapid stress relaxation. In addition, the phenotype of macrophages timely transformed into anti-inflammatory M2 due to the properties of the collagen component, which shortened the duration of inflammation and enhanced cartilage repair. The results indicated that moderate macrophage activation adjusted by hydrogel components and physical properties was critical in modulating inflammation and cartilage regeneration.

Effect of bone morphogenetic protein-2 on proliferation and apoptosis of gastric cancer cells.

OBJECTIVE: To investigate the effects of bone morphogenetic protein-2 (BMP-2) on the proliferation, differentiation and apoptosis of normal human gastric mucosal cells and gastric cancer cells. METHODS: Poorly differentiated gastric cancer BGC823 cells, moderately differentiated gastric cancer cells and normal human gastric mucosal epithelial GES-1 cells were independently treated with recombinant human BMP-2 or its inhibitor Noggin. MTT assay was performed to detect the proliferation, flow cytometry done to measure the cell cycle and apoptosis and immunohistochemistry carried out to determine the expression of cyclin-dependent kinase 4 (CDK4). RESULTS: BMP-2 exerted inhibitory effect on the growth of all types of cells and the inhibition become more evident with the increase of BMP-2 dose. After treatment with 200 ng/ml BMP-2, cancer cells arrested in G1 phase and those in S phase reduced. Gastric cancer cells had higher CDK4 expression than GES-1 cells. BMP-2 decreased CDK-4 expression in cancer cells but had no influence in GES-1 cells. Noggin conferred promotive effect on the growth of 3 types of cells. In 2 types of cancer cells, treatment with 2000 ng/ml Noggin significantly increased the proportion of cells in S phase but reduced that in G1 phase. However, Noggin did not affect the cell cycle of GES-1 cells. The CDK4 expression was markedly increased in 2 types of cancer cells but that of GES-1 remained unchanged after treatment with 2000 ng/ml Noggin. CONCLUSIONS: BMP-2 may inhibit the proliferation of both normal and malignant gastric epithelial cells, down-regulate CDK4 expression in gastric cancer cells and arrest gastric cancer cells in G1-phase in cell cycle. Through antagonizing BMP-2, Noggin, may accelerate the proliferation of gastric cancer cells. Thus, the abnormality of BMP signaling pathway may play an important role in the pathogenesis of gastric cancer.

Three-Dimensional Printing of Large-Scale, High-Resolution Bioceramics with Micronano Inner Porosity and Customized Surface Characterization Design for Bone Regeneration.

Three-dimensional printing technologies have opened up new possibilities for manufacturing bioceramics with complex shapes in a completely digital fabrication process. Some bioceramics have demonstrated elaborate design and high resolution in their small parts through digital light projection (DLP) printing. However, it is still a challenge to prepare large-scale, high-precision ceramics that can effectively regulate the bioactivity of materials. In this study, we fabricated a large-scale hydroxyapatite porous bioceramic (length >150 mm) using DLP. This bioceramic had highly micronanoporous surface structures (printing resolution <65 µm), which could be controlled by adjusting the solid content and sintering process. Both in vitro and in vivo results indicated that the designed bioceramic had promising bone regeneration ability. This study provides significant evidence for exploring the effects of microenvironments on bone tissue regeneration. These results indicated that DLP technology has the potential to produce large-scale bone tissue engineering scaffolds with accurate porosity.

Lysine acetylation of Escherichia coli lactate dehydrogenase regulates enzyme activity and lactate synthesis.

As an evolutionarily conserved posttranslational modification, protein lysine acetylation plays important roles in many physiological and metabolic processes. However, there are few reports about the applications of lysine acetylation in metabolic regulations. Lactate is a main byproduct in microbial fermentation, and itself also an important bulk chemical with considerable commercial values in many fields. Lactate dehydrogenase (LdhA) is the key enzyme catalyzing lactate synthesis from pyruvate. Here, we reported that Escherichia coli LdhA can be acetylated and the acetylated lysine sites were identified by mass spectrometry. The effects and regulatory mechanisms of acetylated sites on LdhA activity were characterized. Finally, lysine acetylation was successfully used to regulate the lactate synthesis. LdhA (K9R) mutant overexpressed strain improved the lactate titer and glucose conversion efficiency by 1.74 folds than that of wild-type LdhA overexpressed strain. LdhA (K154Q-K248Q) mutant can inhibit lactate accumulation and improve 3HP production. Our study established a paradigm for lysine acetylation in lactate synthesis regulation and suggested that lysine acetylation may be a promising strategy to improve the target production and conversion efficiency in microbial synthesis. The application of lysine acetylation in regulating lactate synthesis also provides a reference for the treatment of lactate-related diseases.

The synergistic regulation of chondrogenesis by collagen-based hydrogels and cell co-culture.

The suitable seeding cells and scaffolds are very important for tissue engineering to create functional cartilage. Although the physicochemical properties of scaffold and co-culture system of mesenchymal stem cells (MSCs) and chondrocytes could affect functional properties of engineered cartilage tissues respectively, the combined effects of them on chondrogenesis is currently unknown. Herein, methacrylated collagen (CMA30 and CMA80) hydrogels with different degradation rate and stiffness were prepared. The MSCs and chondrocytes were co-cultured or monocultured in collagen, CMA30 and CMA80 hydrogels in vitro or in vivo. The results demonstrated that cell spreading and proliferation was regulated by degradation rate and stiffness of hydrogels. Compared to single MSCs culture, co-culture cells in all collagen-based hydrogels significantly improved chondrogenesis. CMA30 hydrogel with moderate degradation rate and low storage modulus was the most effective for co-culture system to promote chondrogenesis compared to Col and CMA80 hydrogel in vitro culture, while there was no obvious difference between CMA30 and CMA80 hydrogel in vivo. Furthermore, the intercellular substance exchange was very important for co-culture system to maintain the positive effect on chondrogenesis. Overall, the current study highlights the synergistic effects of the physicochemical properties of collagen-based hydrogel and co-culture system on cartilage formation. STATEMENT OF SIGNIFICANCE: Scaffolds and cells play a key role in cartilage tissue engineering. The combined effects of physicochemical properties of collagen hydrogels and co-culture system (MSCs and chondrocytes) on chondrogenesis is unknown. In contrast to the studies that investigated the effect of single factor (scaffolds or cells) on cartilage formation, this manuscript explored the synergistic regulation of both scaffold properties and biological factors on chondrogenesis, and provided a promising strategy for cartilage tissue engineering.

Bacterial protein acetylation and its role in cellular physiology and metabolic regulation.

Protein acetylation is an evolutionarily conserved posttranslational modification. It affects enzyme activity, metabolic flux distribution, and other critical physiological and biochemical processes by altering protein size and charge. Protein acetylation may thus be a promising tool for metabolic regulation to improve target production and conversion efficiency in fermentation. Here we review the role of protein acetylation in bacterial physiology and metabolism and describe applications of protein acetylation in fermentation engineering and strategies for regulating acetylation status. Although protein acetylation has become a hot topic, the regulatory mechanisms have not been fully characterized. We propose future research directions in protein acetylation.

The effect of collagen hydrogels on chondrocyte behaviors through restricting the contraction of cell/hydrogel constructs.

Collagen is a promising material for tissue engineering, but the poor mechanical properties of collagen hydrogels, which tend to cause contraction under the action of cellular activity, make its application challengeable. In this study, the amino group of type I collagen (Col I) was modified with methacrylic anhydride (MA) and the photo-crosslinkable methacrylate anhydride modified type I collagen (CM) with three different degrees of substitution (DS) was prepared. The physical properties of CM and Col I hydrogels were tested, including micromorphology, mechanical properties and degradation properties. The results showed that the storage modulus and degradation rate of hydrogels could be adjusted by changing the DS of CM. In vitro, chondrocytes were seeded into these four groups of hydrogels and subjected to fluorescein diacetate/propidium iodide (FDA/PI) staining, cell counting kit-8 (CCK-8) test, histological staining and cartilage-related gene expression analysis. In vivo, these hydrogels encapsulating chondrocytes were implanted subcutaneously into nude mice, then histological staining and sulfated glycosaminoglycan (sGAG)/DNA assays were performed. The results demonstrated that contraction of hydrogels affected behaviors of chondrocytes, and CM hydrogels with suitable DS could resist contraction of hydrogels and promote the secretion of cartilage-specific matrix in vitro and in vivo.

Tissue engineered artificial liver model based on viscoelastic hyaluronan-collagen hydrogel and the effect of EGCG intervention on ALD.

In alcoholic liver disease (ALD) research, animal models, as one of the most popular methods to explore pathology and therapeutic drug screening, show the limitations of expensive cost and ethic, as well as long modeling time. To minimize the use of animal models in ALD research, an artificial liver model has been developed by incorporating HepG2 cells into hydrogel matrix based on difunctional hyaluronan and collagen. And on this basis an alcohol-induced ALD model in vitro by adding alcohol in the engineering process has been established. Results showed that the construct exhibited a simulated synthetic and metabolic liver function thanks to the bionic fibrillar and viscoelastic characteristics of hydrogels. And the in vitro alcohol-induced ALD model was also proved to be successfully established, even presenting equal results with ALD mice. Furthermore, epigallocatechin gallate (EGCG) as an intervention on ALD was confirmed in both in vitro and in vivo model. The findings indicate our simple artificial liver model is not only highly predictive but also easy to apply to drug screening and implantation studies, suggesting a promising alternative to animal models. Moreover, as the main active ingredient of tea, EGCG's effective intervention and reversal effect on fatty liver provides support for the theory that green tea could prevent alcoholic fatty liver.

Fluorescence-activated droplet sorting for enhanced pyruvic acid accumulation by Candida glabrata.

One of the goals of metabolic engineering is to engineer strains that can optimally produce target metabolites. However, the current workflow for rational engineering of the metabolic pathway is sometimes time-consuming and labor-intensive. Here, we have established a cost-effective approach for screening for variants secreting metabolites. Different surface display systems were adopted and verified, which anchored pHluorin to the Candida glabrata cell surface to associate pyruvic acid detection with the read out of this reporter. A generalizable simulation approach based on computational fluid dynamics and regularity of generated droplet dimension was presented, which was found to be an efficient design tool to explore microfluidic characteristics or optimization. Finally, a microfluidic platform based on simulation coupled with surface display system was constructed. A mutant exhibiting a 73.6% increase in pyruvic acid production was identified. This ultrahigh-throughput screening pattern offers a practical guide for identifying microbial strains with many traits of interest.

High-Throughput Screening Technology in Industrial Biotechnology.

Based on the development of automatic devices and rapid assay methods, various high-throughput screening (HTS) strategies have been established for improving the performance of industrial microorganisms. We discuss the most significant factors that can improve HTS efficiency, including the construction of screening libraries with high diversity and the use of new detection methods to expand the search range and highlight target compounds. We also summarize applications of HTS for enhancing the performance of industrial microorganisms. Current challenges and potential improvements to HTS in industrial biotechnology are discussed in the context of rapid developments in synthetic biology, nanotechnology, and artificial intelligence. Rational integration will be an important driving force for constructing more efficient industrial microorganisms with wider applications in biotechnology.

Activated hyaluronic acid/collagen composite hydrogel with tunable physical properties and improved biological properties.

Self-crosslinkable and injectable hydrogels were fabricated with collagen type I (Col I) and N-hydroxy sulfosuccinimide activated hyaluronic acid (HA-sNHS) at physiological conditions without any initiators or crosslinkers. The physical properties of hydrogels, such as gelation time, swelling property, degradation property and mechanical property could be regulated by adjusting the substitution degree (DS) of HA-sNHS. Chondrocytes were encapsulated into hydrogels and their proliferation, phenotype maintenance and matrix secretion were characterized. The results demonstrated that chondrocytes in hydrogel Col I/HA-sNHS32% in which the DS of HA-sNHS was 32% secreted more cartilage specific matrix than others. The results of animal experiment demonstrated that hydrogels Col I and Col I/HA-sNHS32% both had good biodegradability and cytocompatibility. This study provided a novel and simple method for fabrication of self-crosslinkable and injectable hydrogels with tunable physical properties. It implied that these hydrogels could find some applications in the fields of cell encapsulation and tissue engineering.

The effects of chemical crosslinking manners on the physical properties and biocompatibility of collagen type I/hyaluronic acid composite hydrogels.

It is necessary to use chemical crosslinking to regulate the mechanical properties, biodegradability and biocompatibility of hydrogels. In this study, three kinds of collagen type I (Col I)/hyaluronic acid (HA) hydrogels with the same ratio and different chemical crosslinking manners were designed and fabricated, and the effects of chemical crosslinking manners on the physical properties and biocompatibility of hydrogels were investigated. The gelation time, mechanical property, swelling and degradability of hydrogels were characterized. Chondrocytes were encapsulated into these hydrogels to detect their effects on cell survival, proliferation, morphology and ECM secretion. Furthermore, the hydrogels were implanted into the back of SD rats to evaluate their biodegradability and biocompatibility in vivo. The results showed that chemical crosslinking manners of hydrogels could affect their physical properties to some extent. Chondrocytes encapsulated into these hydrogels showed a round or oval shape. ECM secretion of cells encapsulated in hydrogels increased with the elongation of culture duration, and cells encapsulated in hydrogels HA-sNHS/Col I (HSC) and HA-CHO/Col I (HCC) secreted more ECM than others. In vivo studies demonstrated that these hydrogels showed similar and acceptable inflammatory reaction.

Effect of cell density on adipogenic differentiation of mesenchymal stem cells.

The effect of cell density on the adipogenic differentiation of human bone marrow-derived mesenchymal stem cells (MSCs) was investigated by using a patterning technique to induce the formation of a cell density gradient on a micropatterned surface. The adipogenic differentiation of MSCs at a density gradient from 5 x 10(3) to 3 x 10(4) cells/cm2 was examined. Lipid vacuoles were observed at all cell densities after 1-3 weeks of culture in adipogenic differentiation medium although the lipid vacuoles were scarce at the low cell density and abundant at the high cell density. Real-time RT-PCR analysis showed that adipogenesis marker genes encoding peroxisome proliferator-activated receptor gamma2 (PPARgamma2), lipoprotein lipase (LPL), and fatty acid binding protein-4 (FABP4) were detected in the MSCs cultured at all cell densities. The results suggest that there was no apparent effect of cell density on the adipogenic differentiation of human MSCs.

Adipogenic differentiation of mesenchymal stem cells on micropatterned polyelectrolyte surfaces.

Three kinds of photoreactive polyelectrolytes of polyallylamine (PAAm), poly(acrylic acid) (PAAc), and poly(vinyl alcohol) (PVA) were synthesized by the introduction of azidophenyl groups in the respective polymers. The photoreactive PAAm, PAAc, and PVA were micropatterned on polystyrene surfaces by photolithography. Observation with optical microscopy and scanning probe microscopy demonstrated the formation of a striped pattern of polyelectrolytes with a width of 200 microm. The micropatterned polyelectrolytes swelled in water. The micropatterned surfaces were used for cell culture of mesenchymal stem cells (MSCs) and their effects on adipogenic differentiation were investigated. The MSCs adhered to and proliferated evenly on the PAAm- and PAAc-patterned surfaces while they formed a cell pattern on the PVA-patterned surface. The PAAm-, PAAc-grafted, and polystyrene surfaces supported cell adhesion while the PVA-grafted surface did not. When cultured in adipogenic differentiation medium, the adipogenic differentiation of MSCs on the polyelectrolyte-patterned surfaces was demonstrated by the formation of lipid vacuoles and gene expression analysis. Oil Red-O-positive cells showed an even distribution on the PAAm- and PAAc-patterned surfaces, while they showed a pattern on the PVA-patterned surface. The fraction of Oil RedO-positive cells increased with culture time. The MSCs cultured on the PAAm-, PAAc-grafted, and polystyrene surfaces in adipogenic differentiation medium expressed the adipogenesis marker genes of peroxisome proliferator-activated receptor gamma2 (PPARgamma2), lipoprotein lipase (LPL), and fatty acid binding protein 4 (FABP4). These results indicate that the PAAm-, and PAAc-grafted, and polystyrene surfaces supported the adipogenesis of MSCs while a PVA-grafted surface did not.