Three-dimensional(3D)stem cell culture systems have attracted considerable attention as a way to better mimic the complex interactions between individual cells and the extracellular matrix(ECM)that occur in vivo.Moreo...Three-dimensional(3D)stem cell culture systems have attracted considerable attention as a way to better mimic the complex interactions between individual cells and the extracellular matrix(ECM)that occur in vivo.Moreover,3D cell culture systems have unique properties that help guide specific functions,growth,and processes of stem cells(e.g.,embryogenesis,morphogenesis,and organogenesis).Thus,3D stem cell culture systems that mimic in vivo environments enable basic research about various tissues and organs.In this review,we focus on the advanced therapeutic applications of stem cell-based 3D culture systems generated using different engineering techniques.Specifically,we summarize the historical advancements of 3D cell culture systems and discuss the therapeutic applications of stem cell-based spheroids and organoids,including engineering techniques for tissue repair and regeneration.展开更多
To investigate the biological character of human adipose-derived adult stem cells (hADAS cells) when cultured in vitro and the relationship between hADAS cell’s replication activity and the donor’s age factor, and t...To investigate the biological character of human adipose-derived adult stem cells (hADAS cells) when cultured in vitro and the relationship between hADAS cell’s replication activity and the donor’s age factor, and to assess the stem cells as a new source for tissue engineering. hADAS cells are isolated from human adipose tissue of different age groups (from adolescents to olds: <20 years old, 21―40 years old, 41―60 years old and >61 years old groups). The protein markers (CD29, CD34, CD44, CD45, CD49d, HLA-DR, CD106) of hADAS cells were detected by flow cytometry (FCM) to identify the stem cell, and the cell cycle was examined for P20 hADAS cells to evaluate the safety of the subculture in vitro. The generative activity of hADAS cells in different age groups was also examined by MTT method. The formula “ log2T D = t logN t ? logN 0” was used to get the time doubling (TD) of the cells. The results showed that the cells kept heredity stabilization by chromosome analysis for at least 20 passages. The TD of these cells increased progressively by ageing, and the TD of the <20 years old group was lower than that of the >61 years old group (statistical analysis of variance (ANOVA), P=0.002, P<0.05). These find- ings suggested that a higher level of hADAS cells replication activity was found in the younger dona- tors, and they represent novel and valuable seed cells for studies of tissue engineering.展开更多
This paper presents a new technique,termed femtosecond laser shock peening ablation in liquids(fs-LSPAL),which can realize simultaneous crack micro/nanomanufacturing and hierarchical micro/nanolaser ablation,giving ri...This paper presents a new technique,termed femtosecond laser shock peening ablation in liquids(fs-LSPAL),which can realize simultaneous crack micro/nanomanufacturing and hierarchical micro/nanolaser ablation,giving rise to the formation of diverse multiscale hierarchical structures,such as macroporous ratcheted structures and enéchelon microfringes decorated with parabolic nanoripples.Through analysis of surface morphologies,many phenomena have been confirmed to take place during fs-LSPAL,including enéchelon cracks,nanostriation,ripple densification,crack branching,and selective formation of high spatial frequency laser-induced periodic surface structures of 100–200 nm in period.At a high laser power of 700 mW,fs-LSPAL at scanning speeds of 0.2 mm s^-1 and 1 mm s^-1 enables the generation of height-fluctuated and height-homogeneous hierarchical structures,respectively.The height-fluctuated structures can be used to induce‘colony’aggregates of embryonic EB3 stem cells.At 200 mW,fs-LSPAL at 1 mm s^-1 is capable of producing homogeneous tilt macroporous structures with cracked structures interleaved among them,which are the synergistic effects of bubble-induced light refraction/reflection ablation and cracks.As shown in this paper,the conventional laser ablation technique integrated with its self-driven unconventional cracking under extreme conditions expands the horizons of extreme manufacturing and offers more opportunities for complex surface structuring,which can potentially be used for biological applications.展开更多
Human pluripotent stem cells(hPSC)hold considerable promise as a source of adult cells for treatment of diseases ranging from diabetes to liver failure.Some of the challenges that limit the clinical/translational impa...Human pluripotent stem cells(hPSC)hold considerable promise as a source of adult cells for treatment of diseases ranging from diabetes to liver failure.Some of the challenges that limit the clinical/translational impact of hPSCs are high cost and difficulty in scaling-up of existing differentiation protocols.In this paper,we sought to address these challenges through the development of bioactive microcapsules.A co-axial flow focusing microfluidic device was used to encapsulate hPSCs in microcapsules comprised of an aqueous core and a hydrogel shell.Importantly,the shell contained heparin moieties for growth factor(GF)binding and release.The aqueous core enabled rapid aggregation of hPSCs into 3D spheroids while the bioactive hydrogel shell was used to load inductive cues driving pluripotency maintenance and endodermal differentiation.Specifically,we demonstrated that one-time,1 h long loading of pluripotency signals,fibroblast growth factor(FGF)-2 and transforming growth factor(TGF)-β1,into bioactive microcapsules was sufficient to induce and maintain pluripotency of hPSCs over the course of 5 days at levels similar to or better than a standard protocol with soluble GFs.Furthermore,stem cell-carrying microcapsules that previously contained pluripotency signals could be reloaded with an endodermal cue,Nodal,resulting in higher levels of endodermal markers compared to stem cells differentiated in a standard protocol.Overall,bioactive heparin-containing core-shell microcapsules decreased GF usage five-fold while improving stem cell phenotype and are well suited for 3D cultivation of hPSCs.展开更多
基金supported by the National Research Foundation of Korea(NRF)grants funded by the Korean government(NRF-2021R1A4A3025206,NRF-2019M3A9H1103737,NRF-2021M3E5E7026407,NRF-2019R1I1A3A0106345).
文摘Three-dimensional(3D)stem cell culture systems have attracted considerable attention as a way to better mimic the complex interactions between individual cells and the extracellular matrix(ECM)that occur in vivo.Moreover,3D cell culture systems have unique properties that help guide specific functions,growth,and processes of stem cells(e.g.,embryogenesis,morphogenesis,and organogenesis).Thus,3D stem cell culture systems that mimic in vivo environments enable basic research about various tissues and organs.In this review,we focus on the advanced therapeutic applications of stem cell-based 3D culture systems generated using different engineering techniques.Specifically,we summarize the historical advancements of 3D cell culture systems and discuss the therapeutic applications of stem cell-based spheroids and organoids,including engineering techniques for tissue repair and regeneration.
基金the Science and Technical Research Funds of Guangdong Province, China (Grant Nos. 2004B34001004 and04009423)
文摘To investigate the biological character of human adipose-derived adult stem cells (hADAS cells) when cultured in vitro and the relationship between hADAS cell’s replication activity and the donor’s age factor, and to assess the stem cells as a new source for tissue engineering. hADAS cells are isolated from human adipose tissue of different age groups (from adolescents to olds: <20 years old, 21―40 years old, 41―60 years old and >61 years old groups). The protein markers (CD29, CD34, CD44, CD45, CD49d, HLA-DR, CD106) of hADAS cells were detected by flow cytometry (FCM) to identify the stem cell, and the cell cycle was examined for P20 hADAS cells to evaluate the safety of the subculture in vitro. The generative activity of hADAS cells in different age groups was also examined by MTT method. The formula “ log2T D = t logN t ? logN 0” was used to get the time doubling (TD) of the cells. The results showed that the cells kept heredity stabilization by chromosome analysis for at least 20 passages. The TD of these cells increased progressively by ageing, and the TD of the <20 years old group was lower than that of the >61 years old group (statistical analysis of variance (ANOVA), P=0.002, P<0.05). These find- ings suggested that a higher level of hADAS cells replication activity was found in the younger dona- tors, and they represent novel and valuable seed cells for studies of tissue engineering.
基金the financial support by RIKEN FY2019‘Emerging Collaboration Seed’of‘Collaboration Seed Fund’(Grant No.100948-201901010000-340130)。
文摘This paper presents a new technique,termed femtosecond laser shock peening ablation in liquids(fs-LSPAL),which can realize simultaneous crack micro/nanomanufacturing and hierarchical micro/nanolaser ablation,giving rise to the formation of diverse multiscale hierarchical structures,such as macroporous ratcheted structures and enéchelon microfringes decorated with parabolic nanoripples.Through analysis of surface morphologies,many phenomena have been confirmed to take place during fs-LSPAL,including enéchelon cracks,nanostriation,ripple densification,crack branching,and selective formation of high spatial frequency laser-induced periodic surface structures of 100–200 nm in period.At a high laser power of 700 mW,fs-LSPAL at scanning speeds of 0.2 mm s^-1 and 1 mm s^-1 enables the generation of height-fluctuated and height-homogeneous hierarchical structures,respectively.The height-fluctuated structures can be used to induce‘colony’aggregates of embryonic EB3 stem cells.At 200 mW,fs-LSPAL at 1 mm s^-1 is capable of producing homogeneous tilt macroporous structures with cracked structures interleaved among them,which are the synergistic effects of bubble-induced light refraction/reflection ablation and cracks.As shown in this paper,the conventional laser ablation technique integrated with its self-driven unconventional cracking under extreme conditions expands the horizons of extreme manufacturing and offers more opportunities for complex surface structuring,which can potentially be used for biological applications.
基金supported in part by the grants from the Mayo Clinic Center for Regenerative Medicine,J.W.Kieckhefer Foundation and Al Nahyan Foundation,from Regenerative Medicine Minnesota(RMM 101617 TR 004)and from NIH(DK107255).
文摘Human pluripotent stem cells(hPSC)hold considerable promise as a source of adult cells for treatment of diseases ranging from diabetes to liver failure.Some of the challenges that limit the clinical/translational impact of hPSCs are high cost and difficulty in scaling-up of existing differentiation protocols.In this paper,we sought to address these challenges through the development of bioactive microcapsules.A co-axial flow focusing microfluidic device was used to encapsulate hPSCs in microcapsules comprised of an aqueous core and a hydrogel shell.Importantly,the shell contained heparin moieties for growth factor(GF)binding and release.The aqueous core enabled rapid aggregation of hPSCs into 3D spheroids while the bioactive hydrogel shell was used to load inductive cues driving pluripotency maintenance and endodermal differentiation.Specifically,we demonstrated that one-time,1 h long loading of pluripotency signals,fibroblast growth factor(FGF)-2 and transforming growth factor(TGF)-β1,into bioactive microcapsules was sufficient to induce and maintain pluripotency of hPSCs over the course of 5 days at levels similar to or better than a standard protocol with soluble GFs.Furthermore,stem cell-carrying microcapsules that previously contained pluripotency signals could be reloaded with an endodermal cue,Nodal,resulting in higher levels of endodermal markers compared to stem cells differentiated in a standard protocol.Overall,bioactive heparin-containing core-shell microcapsules decreased GF usage five-fold while improving stem cell phenotype and are well suited for 3D cultivation of hPSCs.
