<Abstract>Purpose: To investigate the effect of intravitreal injection of basic fibroblast growth factor(bFGF) on activation and proliferation of endogenous retinal progenitor cells in the Royal College of Surge...<Abstract>Purpose: To investigate the effect of intravitreal injection of basic fibroblast growth factor(bFGF) on activation and proliferation of endogenous retinal progenitor cells in the Royal College of Surgeons(RCS) rat. Methods: Twenty-four rats were studied after the 30th postnatal day(≥30). Eighteen RCS-p+/LAV rats were divided into 3 groups: bFGF-treated, vehicle-treated and untreated groups randomly, and 6 RCS-ray+p+/Lav respectively rats were used as normal controls. 6 μl of bFGF (5 μg/10 μl) or vehicle was injected into the vitreous on day 31, 33 and 35 after birth (P31, P33, P35) in the bFGF group and vehicle group respectively, and no injections were administered in the untreated and control groups. All the rats were euthanized, and their eyes were enucleated, hemisected and fixed at 50 d ays after birth for immunohistochemistry and measurement of outer nuclear layer thickness. Results:Nestin and Chx10 were positive in all retinal layers, intravitreal injection of bFGF in retina-dystrophic RCS(RCS-p+/Lav) rats induced intense labeling for the retinal progenitor cell markers Chx10 and Nestin, which were highly colocalized. Fluorescence intensity for both labels was somewhat less in the control rats, and much less in the vehicle-injected rats as well as in the untreated RCS rats. The outer nuclear layer(ONL) was significantly thicker in bFGF group than that in vehicle-treated or untreated group(P<0.01), but thinner than that of the control group(P<0.01). No significant difference was observed in the ONL thickness between the vehicle group and untreated group(P>0.05). Conclusion:bFGF may contribute to the activation of retinal progenitor cells in RCS rats,thus counteract degeneration by promoting the proliferation of the progenitor cells.展开更多
In the brain, there are hundreds of types of specialized neurons and to generate one type of them we need to have neural progenitors for differentiation to specific neuron type. Mesenchymal stem cells (MSCs) are easil...In the brain, there are hundreds of types of specialized neurons and to generate one type of them we need to have neural progenitors for differentiation to specific neuron type. Mesenchymal stem cells (MSCs) are easily isolated, cultured, manipulated ex vivo, showing great potential for therapeutic applications. The adult MSCs have the potential to produce progeny that differentiate into a variety of cell types such as neurons. This fact suggests that MSCs derived neurons are an important cell type and a deep understanding of the molecular characteristics of it would significantly enhance the advancement of cell therapy for neurological disorders. Therefore, in this study, we isolated, identified, and studied neural progenitors by measuring expression levels through neurogenesis pathway of three neural differentiation markers nestin (NES), neurofilament (NF-L), and microtubule association protein (MAP-2) from mouse bone marrow MSCs (mouse bmMSCs) by using butylated hydroxyanisole (BHA) and diethyl sulfoxide (DMSO) as neural inducers agents. The results of immunocytochemistry and Real Time-PCR showed that in contrast to MSCs, neural differentiated cells showed neural progenitor pattern by showing stable increase in NES gene expression through differentiation process with increasing the protein expression through different exposures times, while NF-L gene and protein expression start to increased after 48 h but not replaced the NES expression completely even when its expression passed NES levels. The maturation marker Map-2 expression was low during the duration of differentiation period in protein and gene expression, which prove that these cells are still progenitors and can be redirected into specific type of neurons by further treatments.展开更多
Pancreatic endocrine islets are vital for glucose homeostasis. However, the islet developmental trajectory and its regulatory network are not well understood. To define the features of these specification and differen...Pancreatic endocrine islets are vital for glucose homeostasis. However, the islet developmental trajectory and its regulatory network are not well understood. To define the features of these specification and differentiation processes, we isolated individual islet cells from TgBAC(neurod1:EGFP) transgenic zebrafish and analyzed islet developmental dynamics across four different embryonic stages using a single-cell RNA-seq strategy. We identified proliferative endocrine progenitors, which could be further categorized by different cell cycle phases with the G1/S subpopulation displaying a distinct differentiation potential. We identified endocrine precursors, a heterogeneous intermediate-state population consisting of lineage-primed alpha, beta and delta cells that were characterized by the expression of lineage-specific transcription factors and relatively low expression of terminally differentiation markers. The terminally differentiated alpha, beta, and delta cells displayed stage-dependent differentiation states, which were related to their functional maturation. Our data unveiled distinct states, events and molecular features during the islet developmental transition, and provided resources to comprehensively understand the lineage hierarchy of islet development at the single-cell level.展开更多
基金Supported by Guangdong Science and Technology Plan Grants 2008B030301300
文摘<Abstract>Purpose: To investigate the effect of intravitreal injection of basic fibroblast growth factor(bFGF) on activation and proliferation of endogenous retinal progenitor cells in the Royal College of Surgeons(RCS) rat. Methods: Twenty-four rats were studied after the 30th postnatal day(≥30). Eighteen RCS-p+/LAV rats were divided into 3 groups: bFGF-treated, vehicle-treated and untreated groups randomly, and 6 RCS-ray+p+/Lav respectively rats were used as normal controls. 6 μl of bFGF (5 μg/10 μl) or vehicle was injected into the vitreous on day 31, 33 and 35 after birth (P31, P33, P35) in the bFGF group and vehicle group respectively, and no injections were administered in the untreated and control groups. All the rats were euthanized, and their eyes were enucleated, hemisected and fixed at 50 d ays after birth for immunohistochemistry and measurement of outer nuclear layer thickness. Results:Nestin and Chx10 were positive in all retinal layers, intravitreal injection of bFGF in retina-dystrophic RCS(RCS-p+/Lav) rats induced intense labeling for the retinal progenitor cell markers Chx10 and Nestin, which were highly colocalized. Fluorescence intensity for both labels was somewhat less in the control rats, and much less in the vehicle-injected rats as well as in the untreated RCS rats. The outer nuclear layer(ONL) was significantly thicker in bFGF group than that in vehicle-treated or untreated group(P<0.01), but thinner than that of the control group(P<0.01). No significant difference was observed in the ONL thickness between the vehicle group and untreated group(P>0.05). Conclusion:bFGF may contribute to the activation of retinal progenitor cells in RCS rats,thus counteract degeneration by promoting the proliferation of the progenitor cells.
文摘In the brain, there are hundreds of types of specialized neurons and to generate one type of them we need to have neural progenitors for differentiation to specific neuron type. Mesenchymal stem cells (MSCs) are easily isolated, cultured, manipulated ex vivo, showing great potential for therapeutic applications. The adult MSCs have the potential to produce progeny that differentiate into a variety of cell types such as neurons. This fact suggests that MSCs derived neurons are an important cell type and a deep understanding of the molecular characteristics of it would significantly enhance the advancement of cell therapy for neurological disorders. Therefore, in this study, we isolated, identified, and studied neural progenitors by measuring expression levels through neurogenesis pathway of three neural differentiation markers nestin (NES), neurofilament (NF-L), and microtubule association protein (MAP-2) from mouse bone marrow MSCs (mouse bmMSCs) by using butylated hydroxyanisole (BHA) and diethyl sulfoxide (DMSO) as neural inducers agents. The results of immunocytochemistry and Real Time-PCR showed that in contrast to MSCs, neural differentiated cells showed neural progenitor pattern by showing stable increase in NES gene expression through differentiation process with increasing the protein expression through different exposures times, while NF-L gene and protein expression start to increased after 48 h but not replaced the NES expression completely even when its expression passed NES levels. The maturation marker Map-2 expression was low during the duration of differentiation period in protein and gene expression, which prove that these cells are still progenitors and can be redirected into specific type of neurons by further treatments.
基金the National Key Basic Research Program of China (2015CB942800)the National Key Research and Development Program of China, Stem Cell and Translational Research (2016YFA0100500)the National Natural Science Foundation of China (NSFC)(3187145 31671500, 31730060, and 81371264).
文摘Pancreatic endocrine islets are vital for glucose homeostasis. However, the islet developmental trajectory and its regulatory network are not well understood. To define the features of these specification and differentiation processes, we isolated individual islet cells from TgBAC(neurod1:EGFP) transgenic zebrafish and analyzed islet developmental dynamics across four different embryonic stages using a single-cell RNA-seq strategy. We identified proliferative endocrine progenitors, which could be further categorized by different cell cycle phases with the G1/S subpopulation displaying a distinct differentiation potential. We identified endocrine precursors, a heterogeneous intermediate-state population consisting of lineage-primed alpha, beta and delta cells that were characterized by the expression of lineage-specific transcription factors and relatively low expression of terminally differentiation markers. The terminally differentiated alpha, beta, and delta cells displayed stage-dependent differentiation states, which were related to their functional maturation. Our data unveiled distinct states, events and molecular features during the islet developmental transition, and provided resources to comprehensively understand the lineage hierarchy of islet development at the single-cell level.
