[Objective] The aim was to study the reproduction of the three-line genic male sterile (GMS) lineparent Mian7MB-1 (B. NapusL.) and the seed production of F1 through somatic tissue culture. [Methed] Through hybridi...[Objective] The aim was to study the reproduction of the three-line genic male sterile (GMS) lineparent Mian7MB-1 (B. NapusL.) and the seed production of F1 through somatic tissue culture. [Methed] Through hybridization, a new breeding material Mian 7MB-1 in three-line genic temporary maintainer line propagated by tissue culture was used to improve the sterile plant rate of rapeseed in dual-purpose recessive GMS line, such as Mian 7AB type, S45AB type, and etc. And then the variety comparative test was performed. [Result] In order to avoid some fertility restoration phenomena occurring during the process of self-reproduction, Mian 7AB was propagated in bulk with somatic tissue culture of temporary maintainer line plant stem. The propagated temporary maintainer line seedlings were applied to the breeding and seed production of net room male sterile line parent, promoting the sterile plant rate of the male sterile line parent to 91.7% -93.5%. The male sterile line parents per hectare were enough for the seed production of hybrid F1 in 7 500 -15 000 hm^2. [ Conclusion ] Compared with the original dual-purpose GMS line, the seed production ultilizing male sterile line with high sterile plant rate greatly reduced the labor, significantly improved the seed yield, ensuring the seed quality and forming a perfect breeding and seed production system.展开更多
Soybean somatic cell could induce the development of embryoid which was similar to embryo morphologically and structurally. Somatic embryogenesis system of soybean was used to conduct genetic transformation of soybean...Soybean somatic cell could induce the development of embryoid which was similar to embryo morphologically and structurally. Somatic embryogenesis system of soybean was used to conduct genetic transformation of soybean because of its several advantages such as higher transformational efficiency, beetter synchronism and fewer plant chimeras among transgenic plants. After infected with agrobacterium tumefaciens,the initiation, differentiation and development of young cotyledon embryogenic cell of soybean which was cultured on selective culture medium with kanamycin were investigated through histological study. The result showed that somatic embryo was differentiated in non-bud differentiation way. The embryogenic cells were differentiated from epidermis of explant or cells in 1 layer or 2 layers, with the division of embryogenic cells and degradation and disorganization of surrounding cells, the embryogenic cells would form embryoid with analogous suspensor structure. Later, globular embryoid would extrude from epidermis then developed into heart-shape embryo. The experiment was expected to provide theoretical reference for the construction of high transformational system of using plant somatic embryogenesis induced by young cotyledon of soybean.展开更多
AIM: To investigate the changing pattern of β-catenin expression and its prognostic value in advanced colorectal cancer (CRC). METHODS: Archival tumor samples were analyzed for β-catenin using immunohistochemist...AIM: To investigate the changing pattern of β-catenin expression and its prognostic value in advanced colorectal cancer (CRC). METHODS: Archival tumor samples were analyzed for β-catenin using immunohistochemistry (IHC) in 95 patients with advanced CRC. RESULTS: Membranous β-catenin expression was found in the normal colorectal epithelium. Almost 100% of CRC cases showed membranous and cytoplasmic expression, and 55 (58%) cases showed nuclear expression. In univariate (Kaplan-Meier) survival analysis, only the nuclear index (NI) was a significant predictor of disease free survival (DFS) (P = 0.023; n = 35), with a NI above the median associated with longer DFS (34.2 too) than those with a NI below the median (15.5 too) (P = 0.045, ANOVA). The other indices were not significant predictors of DFS, and none of the three tested indices (for membranous, cytoplasmic, or nuclear expression) predicted diseasespecific survival (DSS). However, when dichotomized as positive or negative nuclear expression, the former was a significant predictor of more favorable DFS (P = 0.041) and DSS (P = 0.046). CONCLUSION: Nuclear β-catenin expression provides additional information in predicting patient outcome in advanced CRC.展开更多
We previously showed that Wnt3a could stimulate human embryonic stem (hES) cell proliferation and affect cell fate determination. In the absence of feeder cell--derived factors, hES cells cultured under a feeder-fre...We previously showed that Wnt3a could stimulate human embryonic stem (hES) cell proliferation and affect cell fate determination. In the absence of feeder cell--derived factors, hES cells cultured under a feeder-free condition survived and proliferated poorly. Adding recombinant Wnt3a in the absence of feeder cell derived-factors stimulated hES cell proliferation but also differentiation. In the present study, we further extended our analysis to other Wnt ligands such as Wntl and Wnt5a. While Wntl displayed a similar effect on hES cells as Wnt3a, Wnt5a had little effect in this system. Wnt3a and Wntl enhanced proliferation of undifferentiated hES cells when feeder-derived self-renewal factors and bFGF are also present. To explore the possibility to promote the proliferation of undifferentiated hES cells by activating the Wnt signaling, we overexpressed Wnt3a or Wntl gene in immortalized human adult fibroblast (HAFi) cells that are superior in supporting long-term growth of undifferentiated hES cells than primary mouse embryonic fibroblasts. HAFi cells with or without a Wnt tmnsgene can be propagated indefinitely. Over-expression of the Wnt3a gene significantly enhanced the ability of HAFi feeder cells to support the undifferentiated growth of 3 different hES cell lines we tested. Co-expression of three commonly-used drug selection genes in Wnt3a-overpressing HAFi cells further enabled us to select rare hES clones after stable transfection or transduction. These immortalized engineered feeder cells (W3R) that co-express growth-promoting genes such as Wnt3a and three drug selection genes should empower us to efficiently make genetic modified hES cell lines for basic and translational research.展开更多
Objective: To prepare microencapsulated cells releasing human tissue inhibitor ofmetalloproteinase-2 (TIMP-2), and investigate their biological characteristics in vitro. Methods: Chinese hamster ovary (CHO) cell...Objective: To prepare microencapsulated cells releasing human tissue inhibitor ofmetalloproteinase-2 (TIMP-2), and investigate their biological characteristics in vitro. Methods: Chinese hamster ovary (CHO) cells were stably transfected with a human TIMP-2 expression vector, encapsulated in barium alginate microcapsules and cultured in vitro. Morphological appearance of the microcapsules was observed under a light microscope. Cell viability was assessed using MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay. Enzyme linked immunosorbent assay (ELISA) and reverse zymography were used to confirm the release of biologically active TIMP-2 from the microcapsules. Cryopreservation study of the microencapsulated cells was carried out using dimethyl sulfoxide (DMSO) as preservative agent. Results: The microcapsules appeared like a sphere with diameter of 300-600 ~tm. The surface of the capsule wall was clearly smooth. The microencapsulated cells survived well and kept proliferating over the 6 weeks observed. No significant difference in TIMP-2 secretion was found between encapsulated and unencapsulated cells. Reverse zymography confirmed the bioactivity of MMP (matrix metalloproteinase) inhibition of TIMP-2. The cryopreservation process did not damage the microcapsule morphology nor the viability of the cells inside. Conclusion: Microencapsulated engineered CHO cells survive at least 6 weeks after preparation in vitro, and secrete bioactive TIMP-2 freely from the microcapsules.展开更多
The histological hallmark of autoimmune hepatitis(AIH) is a dense portal mononuclear cell infiltrate that invades the surrounding parenchyma and comprises T and B lymphocytes,macrophages,and plasma cells.An unknown ...The histological hallmark of autoimmune hepatitis(AIH) is a dense portal mononuclear cell infiltrate that invades the surrounding parenchyma and comprises T and B lymphocytes,macrophages,and plasma cells.An unknown but powerful stimulus must be promoting the formation of this massive inflammatory cellular reaction that is likely to initiate and perpetuate liver damage.An autoimmune attack can follow different pathways to inflict damage on hepatocytes.Liver damage is likely to be orchestrated by CD4^+ T lymphocytes recognizing an autoantigenic liver peptide.To trigger an autoimmune response,the peptide must be embraced by an HLA class Ⅱ molecule and presented to naive CD4^+ T helper(Th0) cells by professional antigen presenting cells,with the co-stimulation of ligand-ligand fostering interaction between the two cells.Th0 cells become activated,differentiate into functional phenotypes according to the cytokines prevailing in the microenvironment and the nature of the antigen,and initiate a cascade of immune reactions determined by the cytokines produced by the activated T cells.Th1 cells,arising in the presence of the macrophage-derived interleukin(IL) -12,secrete mainly IL-2 and interferon-gamma(IFN-γ),which activate macrophages,enhance expression of HLA classⅠ(increasing liver cell vulnerability to a CD8^+ T cell cytotoxic attack),and induce expression of HLA class Ⅱ molecules on hepatocytes.Th2 cells,which differentiate from Th0 if the microenvironment is rich in IL-4,produce mainly IL-4,IL-10,and IL-13 which favour autoantibody production by B lymphocytes.Physiologically,Th1 and Th2 antagonize each other.Th17 cells,a recently described population,arise in the presence of transforming growth factor beta(TGF-β) and IL-6 and appear to have an important effector role in inflammation and autoimmunity.Theprocess of autoantigen recognition is strictly controlled by regulatory mechanisms,such as those exerted by CD4^+CD25^+ regulatory T cells,which derive from Th0 in the presence of TGF-β,but in the absence of IL-6.If regulatory mechanisms fail,the autoimmune attack is perpetuated.Over the past three decades different aspects of the above pathogenic scenario have been investigated.In particular,a defect in immunoregulation affecting CD4^+CD25^+ regulatory T cells(T-regs) has been demonstrated in AIH,particularly at diagnosis or during relapse.Advances in the study of autoreactive T cells have occurred mostly in AIH type 2,since the knowledge that CYP2D6 is the main autoantigen has enabled the characterization of both CD4 and CD8 T cells targeting this cytochrome.CD4 T cells from patients with type 2 AIH positive for the predisposing HLA allele DRB10701 recognize seven regions of CYP2D6,five of which are also recognized by CD8 T cells.High numbers of IFN-γ producing CD4 T cells and CD8 T cells are associated with biochemical evidence of liver damage,suggesting a combined cellular immune attack.展开更多
AIM: To understand which and how different miRNAs are implicated in the process of hepatic stellate cell (HSC) activation. METHODS: We used microarrays to examine the differential expression of miRNAs during in vitro ...AIM: To understand which and how different miRNAs are implicated in the process of hepatic stellate cell (HSC) activation. METHODS: We used microarrays to examine the differential expression of miRNAs during in vitro activation of primary HSCs (pHSCs). The transcriptome changes upon stable transfection of rno-miR-146a into an HSC cell line were studied using cDNA microarrays. Selected differentially regulated miRNAs were investigated by quantitative real-time polymerase chain reaction during in vivo HSC activation. The effect of miRNA mimics and inhibitor on the in vitro activation of pHSCs was also evaluated.RESULTS: We found that 16 miRNAs were upregulated and 26 were downregulated significantly in 10-d in vitro activated pHSCs in comparison to quiescent pHSCs. Overexpression of rno-miR-146a was characterized by marked upregulation of tissue inhibitor of metalloproteinase-3, which is implicated in the regulation of tumor necrosis factor-α activity. Differences in the regulation of selected miRNAs were observed comparing in vitro and in vivo HSC activation. Treatment with miR-26a and 29a mimics, and miR-214 inhibitor during in vitro activation of pHSCs induced significant downregulation of collagen type Ⅰ transcription. CONCLUSION: Our results emphasize the different regulation of miRNAs in in vitro and in vivo activated pHSCs. We also showed that miR-26a, 29a and 214 are involved in the regulation of collagen type I mRNA.展开更多
Caveolin-2,a protein about 20 kD,is a major component of the inner surface of caveolae,small invaginations of the plasma membrane.Similar with caveolin-1 and caveolin-3,it serves as a protein marker of caveolae.Caveol...Caveolin-2,a protein about 20 kD,is a major component of the inner surface of caveolae,small invaginations of the plasma membrane.Similar with caveolin-1 and caveolin-3,it serves as a protein marker of caveolae.Caveolin-1 and-2 are located next to each other at 7q31.1 on human chromosome,the proteins encoded are co-localized and form a stable hetero-oligomeric complex,distributing similarly in tissue and cultured cells.Caveolin-3 is located on different chromosomes but confirmed to interact with caveolin-2.Caveolin-2 is similar to caveolin-1 in many respects but differs from the latter in functional domains,especially in G-protein binding domain and caveolin scaffolding domain.The mRNAs of both caveolin-1 and caveolin-2 are most abundantly expressed in white adipose tissue and are induced during differentiation of 3T3-L1 cells to adipocytes.Caveolin-2-deficinet mice demonstrate clear pulmonary defects,with little or no change in caveolin-1 expression and caveolae formation,suggesting that caveolin-2 plays a selective role in lung functions.Caveolin-2 is also involved in lipid metabolism and human cancers.展开更多
Objective: In order to evaluate potential application for diagnosis and prognosis of non-small cell-lung cancer (NSCLC), as well as to determine its role in the pathogenesis of the disease, we prepared anti-human h...Objective: In order to evaluate potential application for diagnosis and prognosis of non-small cell-lung cancer (NSCLC), as well as to determine its role in the pathogenesis of the disease, we prepared anti-human hnRNPA2/B1 potyclonal antibody. Methods: Prokaryotic expression vector of pET28a (+)-hnRNP A2/B1 was constructed and bansformed into E.coli BL21. The recombinant protein induced by IPTG was purified and injected to rabbits for antibody preparation. Expression of hnRN P A2/B1 was examined in 45 tissues of NSCLC and 16 inflammatory pseudotumor tissues of lung by immunohistochemistry with the antibody. The commercial hnRNP A2/B1 monoclonal antibody was used as a controI.Results: (1) Polyclonal an-tibody against hnRNP A2/B1 with high title was obtained. (2) The positive staining in NSCLC tissues was 62.22%, which was substantially higher than that in normal tissues (40%, P = 0.035) or inflammatory pseudotumor tissues (31.25%, P=0.033). (3) Expression of hnRNP A2/B1 positively correlated with age and the history of smoking, whereas it negatively correlated with differentiation staging of tumors. (4) Follow-up study showed that the survival time of patients with positive staining was significantly shorter than that of patients without hnRNP A2/B1 expression (P=0.048). Conclusion: It is successful to make the recombinant protein and prepare the polyclonal antibody agonist human hnRNP A2/B1. It may be a valuable marker for the diagnosis and prognosis of NSCLC. Our results provide a basis for further study in clinical application.展开更多
[Objective]As a mosquito-repelling ornamental plant,Pelargonium×Citrosum Vanleenii(P.× Citrosum Vanleenii)is hard to be acquired because of its hybrid background,the paper was to a new regeneration system of...[Objective]As a mosquito-repelling ornamental plant,Pelargonium×Citrosum Vanleenii(P.× Citrosum Vanleenii)is hard to be acquired because of its hybrid background,the paper was to a new regeneration system of(P.× Citrosum Vanleenii).[Method] By studying the influence of plant growth regulators(PGRs)on explant type(leaves and petioles),the optimal combinations of PGRs to maximize SELSs(somatic embryo-like structure)and buds were established.[Result]0.2 mg/L NAA+1.0 mg/L BA was best for LS(leaves segments)and 0.2 mg/L NAA + 1.5 mg/L BAs was best for PS(petioles segments).Cultured plantlets were successfully acclimatized in soil where they grew normally without any morphological variation.Although both LS and PS were usable,the leaf was a better explant for induction of embryogenic calli,somatic embryo-like structures and buds.[Conclusion]This work offered a rapid and efficient system for plant regeneration of P.×Citrosum Vanleenii.展开更多
Mouse oocytes undergo polarization during meiotic maturation, and this polarization is essential for asymmetric cell divisions that maximize retention of maternal components required for early development. Without con...Mouse oocytes undergo polarization during meiotic maturation, and this polarization is essential for asymmetric cell divisions that maximize retention of maternal components required for early development. Without conventional centrosomes, the meiotic spindle has less focused poles and is barrel-shaped. The migration of meiotic spindles to the cortex is accompanied by a local reorganization and polarization of the cortex. LGN is a conserved protein involved in cell polarity and regulation of spindle organization. In the present study, we characterized the localization dynamics of LGN during mouse oocyte maturation and analyzed the effects of LGN upregulation and downregulation on meiotic spindle organization. At the germinal vesicle stage, LGN is distributed both cytoplasmically and at the cortex. During maturation, LGN localizes to the meiotic spindle apparatus and cortical LGN becomes less concentrated at the actin cap region. Excessive LGN induces meiotic spindle organization defects by elongating the spindle and enhancing pole focusing, whereas depletion of LGN by RNA interference results in meiotic spindle deformation and chromosome misalignment. Furthermore, the N-terminus of LGN has the ability of full-length LGN to regulate spindle organization, whereas the C-terminus of LGN controls cortical localization and polarization. Our results reveal that LGN is cortically polarized in mouse oocytes and is critical for meiotic spindle organization.展开更多
基金Supported by "11thFive-Year" Crop Breeding Research of SichuanProvince "11thFive-Year" Joint Breeding Research Project Fun-ding of Sichuan Province.~~
文摘[Objective] The aim was to study the reproduction of the three-line genic male sterile (GMS) lineparent Mian7MB-1 (B. NapusL.) and the seed production of F1 through somatic tissue culture. [Methed] Through hybridization, a new breeding material Mian 7MB-1 in three-line genic temporary maintainer line propagated by tissue culture was used to improve the sterile plant rate of rapeseed in dual-purpose recessive GMS line, such as Mian 7AB type, S45AB type, and etc. And then the variety comparative test was performed. [Result] In order to avoid some fertility restoration phenomena occurring during the process of self-reproduction, Mian 7AB was propagated in bulk with somatic tissue culture of temporary maintainer line plant stem. The propagated temporary maintainer line seedlings were applied to the breeding and seed production of net room male sterile line parent, promoting the sterile plant rate of the male sterile line parent to 91.7% -93.5%. The male sterile line parents per hectare were enough for the seed production of hybrid F1 in 7 500 -15 000 hm^2. [ Conclusion ] Compared with the original dual-purpose GMS line, the seed production ultilizing male sterile line with high sterile plant rate greatly reduced the labor, significantly improved the seed yield, ensuring the seed quality and forming a perfect breeding and seed production system.
基金the National Natural Science Foundation of China (C02020504)the Scientific and Techrological Developing Scheme of Jilin Province (20050217-2+1 种基金20060204)the national 863 project (2006AA100104-17)~~
文摘Soybean somatic cell could induce the development of embryoid which was similar to embryo morphologically and structurally. Somatic embryogenesis system of soybean was used to conduct genetic transformation of soybean because of its several advantages such as higher transformational efficiency, beetter synchronism and fewer plant chimeras among transgenic plants. After infected with agrobacterium tumefaciens,the initiation, differentiation and development of young cotyledon embryogenic cell of soybean which was cultured on selective culture medium with kanamycin were investigated through histological study. The result showed that somatic embryo was differentiated in non-bud differentiation way. The embryogenic cells were differentiated from epidermis of explant or cells in 1 layer or 2 layers, with the division of embryogenic cells and degradation and disorganization of surrounding cells, the embryogenic cells would form embryoid with analogous suspensor structure. Later, globular embryoid would extrude from epidermis then developed into heart-shape embryo. The experiment was expected to provide theoretical reference for the construction of high transformational system of using plant somatic embryogenesis induced by young cotyledon of soybean.
基金Grants from the Special Government Funding (EVO) allocated to Turku University Central Hospital and Cancer Society of South-West Finland (Turku)
文摘AIM: To investigate the changing pattern of β-catenin expression and its prognostic value in advanced colorectal cancer (CRC). METHODS: Archival tumor samples were analyzed for β-catenin using immunohistochemistry (IHC) in 95 patients with advanced CRC. RESULTS: Membranous β-catenin expression was found in the normal colorectal epithelium. Almost 100% of CRC cases showed membranous and cytoplasmic expression, and 55 (58%) cases showed nuclear expression. In univariate (Kaplan-Meier) survival analysis, only the nuclear index (NI) was a significant predictor of disease free survival (DFS) (P = 0.023; n = 35), with a NI above the median associated with longer DFS (34.2 too) than those with a NI below the median (15.5 too) (P = 0.045, ANOVA). The other indices were not significant predictors of DFS, and none of the three tested indices (for membranous, cytoplasmic, or nuclear expression) predicted diseasespecific survival (DSS). However, when dichotomized as positive or negative nuclear expression, the former was a significant predictor of more favorable DFS (P = 0.041) and DSS (P = 0.046). CONCLUSION: Nuclear β-catenin expression provides additional information in predicting patient outcome in advanced CRC.
文摘We previously showed that Wnt3a could stimulate human embryonic stem (hES) cell proliferation and affect cell fate determination. In the absence of feeder cell--derived factors, hES cells cultured under a feeder-free condition survived and proliferated poorly. Adding recombinant Wnt3a in the absence of feeder cell derived-factors stimulated hES cell proliferation but also differentiation. In the present study, we further extended our analysis to other Wnt ligands such as Wntl and Wnt5a. While Wntl displayed a similar effect on hES cells as Wnt3a, Wnt5a had little effect in this system. Wnt3a and Wntl enhanced proliferation of undifferentiated hES cells when feeder-derived self-renewal factors and bFGF are also present. To explore the possibility to promote the proliferation of undifferentiated hES cells by activating the Wnt signaling, we overexpressed Wnt3a or Wntl gene in immortalized human adult fibroblast (HAFi) cells that are superior in supporting long-term growth of undifferentiated hES cells than primary mouse embryonic fibroblasts. HAFi cells with or without a Wnt tmnsgene can be propagated indefinitely. Over-expression of the Wnt3a gene significantly enhanced the ability of HAFi feeder cells to support the undifferentiated growth of 3 different hES cell lines we tested. Co-expression of three commonly-used drug selection genes in Wnt3a-overpressing HAFi cells further enabled us to select rare hES clones after stable transfection or transduction. These immortalized engineered feeder cells (W3R) that co-express growth-promoting genes such as Wnt3a and three drug selection genes should empower us to efficiently make genetic modified hES cell lines for basic and translational research.
文摘Objective: To prepare microencapsulated cells releasing human tissue inhibitor ofmetalloproteinase-2 (TIMP-2), and investigate their biological characteristics in vitro. Methods: Chinese hamster ovary (CHO) cells were stably transfected with a human TIMP-2 expression vector, encapsulated in barium alginate microcapsules and cultured in vitro. Morphological appearance of the microcapsules was observed under a light microscope. Cell viability was assessed using MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay. Enzyme linked immunosorbent assay (ELISA) and reverse zymography were used to confirm the release of biologically active TIMP-2 from the microcapsules. Cryopreservation study of the microencapsulated cells was carried out using dimethyl sulfoxide (DMSO) as preservative agent. Results: The microcapsules appeared like a sphere with diameter of 300-600 ~tm. The surface of the capsule wall was clearly smooth. The microencapsulated cells survived well and kept proliferating over the 6 weeks observed. No significant difference in TIMP-2 secretion was found between encapsulated and unencapsulated cells. Reverse zymography confirmed the bioactivity of MMP (matrix metalloproteinase) inhibition of TIMP-2. The cryopreservation process did not damage the microcapsule morphology nor the viability of the cells inside. Conclusion: Microencapsulated engineered CHO cells survive at least 6 weeks after preparation in vitro, and secrete bioactive TIMP-2 freely from the microcapsules.
文摘The histological hallmark of autoimmune hepatitis(AIH) is a dense portal mononuclear cell infiltrate that invades the surrounding parenchyma and comprises T and B lymphocytes,macrophages,and plasma cells.An unknown but powerful stimulus must be promoting the formation of this massive inflammatory cellular reaction that is likely to initiate and perpetuate liver damage.An autoimmune attack can follow different pathways to inflict damage on hepatocytes.Liver damage is likely to be orchestrated by CD4^+ T lymphocytes recognizing an autoantigenic liver peptide.To trigger an autoimmune response,the peptide must be embraced by an HLA class Ⅱ molecule and presented to naive CD4^+ T helper(Th0) cells by professional antigen presenting cells,with the co-stimulation of ligand-ligand fostering interaction between the two cells.Th0 cells become activated,differentiate into functional phenotypes according to the cytokines prevailing in the microenvironment and the nature of the antigen,and initiate a cascade of immune reactions determined by the cytokines produced by the activated T cells.Th1 cells,arising in the presence of the macrophage-derived interleukin(IL) -12,secrete mainly IL-2 and interferon-gamma(IFN-γ),which activate macrophages,enhance expression of HLA classⅠ(increasing liver cell vulnerability to a CD8^+ T cell cytotoxic attack),and induce expression of HLA class Ⅱ molecules on hepatocytes.Th2 cells,which differentiate from Th0 if the microenvironment is rich in IL-4,produce mainly IL-4,IL-10,and IL-13 which favour autoantibody production by B lymphocytes.Physiologically,Th1 and Th2 antagonize each other.Th17 cells,a recently described population,arise in the presence of transforming growth factor beta(TGF-β) and IL-6 and appear to have an important effector role in inflammation and autoimmunity.Theprocess of autoantigen recognition is strictly controlled by regulatory mechanisms,such as those exerted by CD4^+CD25^+ regulatory T cells,which derive from Th0 in the presence of TGF-β,but in the absence of IL-6.If regulatory mechanisms fail,the autoimmune attack is perpetuated.Over the past three decades different aspects of the above pathogenic scenario have been investigated.In particular,a defect in immunoregulation affecting CD4^+CD25^+ regulatory T cells(T-regs) has been demonstrated in AIH,particularly at diagnosis or during relapse.Advances in the study of autoreactive T cells have occurred mostly in AIH type 2,since the knowledge that CYP2D6 is the main autoantigen has enabled the characterization of both CD4 and CD8 T cells targeting this cytochrome.CD4 T cells from patients with type 2 AIH positive for the predisposing HLA allele DRB10701 recognize seven regions of CYP2D6,five of which are also recognized by CD8 T cells.High numbers of IFN-γ producing CD4 T cells and CD8 T cells are associated with biochemical evidence of liver damage,suggesting a combined cellular immune attack.
基金Supported by Institute of Bioengineering and Nanotechnology (Biomedical Research Council, Agency for Science, Technology and Research, Singapore)
文摘AIM: To understand which and how different miRNAs are implicated in the process of hepatic stellate cell (HSC) activation. METHODS: We used microarrays to examine the differential expression of miRNAs during in vitro activation of primary HSCs (pHSCs). The transcriptome changes upon stable transfection of rno-miR-146a into an HSC cell line were studied using cDNA microarrays. Selected differentially regulated miRNAs were investigated by quantitative real-time polymerase chain reaction during in vivo HSC activation. The effect of miRNA mimics and inhibitor on the in vitro activation of pHSCs was also evaluated.RESULTS: We found that 16 miRNAs were upregulated and 26 were downregulated significantly in 10-d in vitro activated pHSCs in comparison to quiescent pHSCs. Overexpression of rno-miR-146a was characterized by marked upregulation of tissue inhibitor of metalloproteinase-3, which is implicated in the regulation of tumor necrosis factor-α activity. Differences in the regulation of selected miRNAs were observed comparing in vitro and in vivo HSC activation. Treatment with miR-26a and 29a mimics, and miR-214 inhibitor during in vitro activation of pHSCs induced significant downregulation of collagen type Ⅰ transcription. CONCLUSION: Our results emphasize the different regulation of miRNAs in in vitro and in vivo activated pHSCs. We also showed that miR-26a, 29a and 214 are involved in the regulation of collagen type I mRNA.
基金Supported by National Basic Research Program of China (973 Program) (2004CB518602,2006CB503909)National High Technology Research and Development Program of China (863 Program) (2009AA02Z192)
文摘Caveolin-2,a protein about 20 kD,is a major component of the inner surface of caveolae,small invaginations of the plasma membrane.Similar with caveolin-1 and caveolin-3,it serves as a protein marker of caveolae.Caveolin-1 and-2 are located next to each other at 7q31.1 on human chromosome,the proteins encoded are co-localized and form a stable hetero-oligomeric complex,distributing similarly in tissue and cultured cells.Caveolin-3 is located on different chromosomes but confirmed to interact with caveolin-2.Caveolin-2 is similar to caveolin-1 in many respects but differs from the latter in functional domains,especially in G-protein binding domain and caveolin scaffolding domain.The mRNAs of both caveolin-1 and caveolin-2 are most abundantly expressed in white adipose tissue and are induced during differentiation of 3T3-L1 cells to adipocytes.Caveolin-2-deficinet mice demonstrate clear pulmonary defects,with little or no change in caveolin-1 expression and caveolae formation,suggesting that caveolin-2 plays a selective role in lung functions.Caveolin-2 is also involved in lipid metabolism and human cancers.
基金a grant from the Provincial Natural Sciences Foundation of Anhui(No.050430703)Major Scientific Research Programs of the Department of Science and Technology of Anhui(No.05023086)
文摘Objective: In order to evaluate potential application for diagnosis and prognosis of non-small cell-lung cancer (NSCLC), as well as to determine its role in the pathogenesis of the disease, we prepared anti-human hnRNPA2/B1 potyclonal antibody. Methods: Prokaryotic expression vector of pET28a (+)-hnRNP A2/B1 was constructed and bansformed into E.coli BL21. The recombinant protein induced by IPTG was purified and injected to rabbits for antibody preparation. Expression of hnRN P A2/B1 was examined in 45 tissues of NSCLC and 16 inflammatory pseudotumor tissues of lung by immunohistochemistry with the antibody. The commercial hnRNP A2/B1 monoclonal antibody was used as a controI.Results: (1) Polyclonal an-tibody against hnRNP A2/B1 with high title was obtained. (2) The positive staining in NSCLC tissues was 62.22%, which was substantially higher than that in normal tissues (40%, P = 0.035) or inflammatory pseudotumor tissues (31.25%, P=0.033). (3) Expression of hnRNP A2/B1 positively correlated with age and the history of smoking, whereas it negatively correlated with differentiation staging of tumors. (4) Follow-up study showed that the survival time of patients with positive staining was significantly shorter than that of patients without hnRNP A2/B1 expression (P=0.048). Conclusion: It is successful to make the recombinant protein and prepare the polyclonal antibody agonist human hnRNP A2/B1. It may be a valuable marker for the diagnosis and prognosis of NSCLC. Our results provide a basis for further study in clinical application.
基金Supported by Fund of Jinhua Science Technology Foundation of China(2009-2-02)
文摘[Objective]As a mosquito-repelling ornamental plant,Pelargonium×Citrosum Vanleenii(P.× Citrosum Vanleenii)is hard to be acquired because of its hybrid background,the paper was to a new regeneration system of(P.× Citrosum Vanleenii).[Method] By studying the influence of plant growth regulators(PGRs)on explant type(leaves and petioles),the optimal combinations of PGRs to maximize SELSs(somatic embryo-like structure)and buds were established.[Result]0.2 mg/L NAA+1.0 mg/L BA was best for LS(leaves segments)and 0.2 mg/L NAA + 1.5 mg/L BAs was best for PS(petioles segments).Cultured plantlets were successfully acclimatized in soil where they grew normally without any morphological variation.Although both LS and PS were usable,the leaf was a better explant for induction of embryogenic calli,somatic embryo-like structures and buds.[Conclusion]This work offered a rapid and efficient system for plant regeneration of P.×Citrosum Vanleenii.
文摘Mouse oocytes undergo polarization during meiotic maturation, and this polarization is essential for asymmetric cell divisions that maximize retention of maternal components required for early development. Without conventional centrosomes, the meiotic spindle has less focused poles and is barrel-shaped. The migration of meiotic spindles to the cortex is accompanied by a local reorganization and polarization of the cortex. LGN is a conserved protein involved in cell polarity and regulation of spindle organization. In the present study, we characterized the localization dynamics of LGN during mouse oocyte maturation and analyzed the effects of LGN upregulation and downregulation on meiotic spindle organization. At the germinal vesicle stage, LGN is distributed both cytoplasmically and at the cortex. During maturation, LGN localizes to the meiotic spindle apparatus and cortical LGN becomes less concentrated at the actin cap region. Excessive LGN induces meiotic spindle organization defects by elongating the spindle and enhancing pole focusing, whereas depletion of LGN by RNA interference results in meiotic spindle deformation and chromosome misalignment. Furthermore, the N-terminus of LGN has the ability of full-length LGN to regulate spindle organization, whereas the C-terminus of LGN controls cortical localization and polarization. Our results reveal that LGN is cortically polarized in mouse oocytes and is critical for meiotic spindle organization.