Establishment and characterization of two new human embryonic stem cell lines, SYSU-1 and SYSU-2

Background Human embryonic stem cells can propagate indefinitely in vitro and are able to differentiate into derivatives of all three embryonic germ layers. The excitement surrounding human embryonic stem cells lies largely in their potential to produce specialized cells that can be used for transplant therapies. However, further investigation requires additional cell lines with varying genetic background. Therefore, efforts to derive and establish more human embryonic stern cell lines are highly warranted. Methods Surplus embryos （blastocysts） from donors were used to isolate the inner cell mass by immunosurgery. All cells were cultured continuously on irradiated murine embryonic fibroblasts feed layer and likely human embryonic stem cell colonies were subsequently characterized by cell surface marker staining, karyotyping and teratoma formation. Results Two human embryonic stern cell lines （SYSU-1 and SYSU-2） were established from surplus embryos. The two lines express several pluripotency markers including alkaline phosphatase, SSEA- 4, Tra-1-60, Oct-4, Nanog and Rex-1. They remain in undifferentiated state with normal karyotype after prolonged passages and can form embryoid bodies in vitro and teratoma in vivo. Conclusion Two new human embryonic stem cell lines have been established from surplus embryos. They can be used to understand selfrenewal and differentiating mechanisms and provide more choices for regenerative medicine.     

Establishment of human embryonic stem cell line from gamete donors

Background Human embryonic stem (HES) cell derived from human blastocyst can be propagated indefinitely in the primitive undifferentiated state while remaining pluripotent. It has exciting potential in human developmental biology, drug discovery, and transplantation medicine. But there are insufficient HES cell lines for further study. Methods Three oocyte donors were studied, and 3 in vitro fertilization (IVF) cycles were carried out to get blastocysts for the establishment of HES cell line. Isolated from blastocysts immunosurgically, inner cell mass (ICM) was cultured and propagated on mouse embryonic fibroblasts (MEFs). Once established, morphology, cell surface markers, karyotype and differentiating ability of the cell line were thoroughly analyzed. Results Four ICMs from 7 blastocysts were cultured on MEFs. After culture, one cell line ( criES-1 ) was established and met the criteria for defining human pluripotent stem cells including a series of markers used to identify pluripotent stem cells, morphological similarity to primate embryonic stem cells and HES reported else where. Normal and stable karyotype maintained over 60 passages, and demonstrated ability to differentiate into a wide variety of cell types. Conclusions HES cell lines can be established from gamete donors at a relatively highly efficient rate. The establishment will exert a widesoread impact on biomedical research.     

The labeling of C57BL/6j derived embryonic stem cells with enhanced green fluorescent protein

Objective To labele MESPU35,a embryonic stem(ES)cell line derived from C57BL/6j mouse,with enhanced green fluorescent protein(EGFP)for further application.Methods The EGFP gene was controlled by the hybrid CA promoter/enhancer (CMV enhancer/chicken beta-actin promoter/beta-actin intron)to construct the vector of the transgene,pCA-EGFP.The vector was transfected into MESPU35 by electroporation.Results We generated EGFP expressing ES cells demonstrating normal properties.The green fluorescence of EGFP expressing cells was maintained in propagation of the ES cells for more than 30 passages as well as in differentiated cells.Cultured in suspension,the“green”ES cells aggregated,and formed embryoid bodies maintaining the green fluorescence at varying developmental stages.The“green” embryoid bodies could expand and differentiate into various types of cells,exhibiting ubiquitous green fluorescence.Concluslons The hybrid CA promoter/enhancer used to control the EGFP expressing ES cells,resulted in more intense and ubiquitous activity.The EGFP transfected cells yield bright green fluorescence,which can be visualized in real time and in situ.In addition,the ES cells,MESPU35,are derived from C57BL/6j mice,which are the most widely used in oncology,physiology and genetics.Compared to 129 substrains.C57BL/6j mice avoid a number of potential problems apparent in the other strains.     

Establishment of cervical lymph node metastasis model of squamous cell carcinoma in the oral cavity in mice

Background Oral squamous cell carcinoma （OSCC） is the most prevalent malignant tumor in the head and neck region, comprising more than 90% of all oral malignancies. A feasible approach for an animal model to study OSCC lymph node metastasis was established and biological behaviors of three oral squamous cell carcinoma cell lines were compared. Methods After implanting three kinds of cell lines （GDC185, Tca8113, Tca83） into three different anatomical sites in nude mice, namely the tongue, floor of the mouth, and axillary fossa, we observed the tumorigenicity and the metastatic capacity, which was confirmed by histopathology under a surgical microscope. Results The animal model injected with GDC185 cells into the floor of the mouth had the highest rate of neck lymph node metastasis （55.6%） and the cell lines had significantly different biological behaviors. Conclusions Nude mice injected with GDC185 cells into the floor of the mouth could be used as a feasible animal model to study neck metastasis of oral squamous cell carcinoma.     

1-MT enhances potency of tumor cell lysate-pulsed dendritic cells against pancreatic adenocarcinoma by downregulating the percentage of tregs

This study examined whether 1-methyl-tryptophan [1-MT,an indoleamine 2,3-dioxygenase(IDO) inhibitor] could reduce CD4+CD25+ regulatory T cells(Tregs) proliferation and improve the anti-tumor efficacy of dendritic cells(DCs) pulsed with tumor cell lysate in the mice bearing pancreatic adenocarcinoma.The models of pancreatic adenocarcinoma were established in C57BL/6 mice by subcutaneous injection of Pan02 cells.Eight mice which were subcutaneously injected with PBS served as control.The expression of IDO was...     

Anti-tumor Effects of pNEgr-mlL-12 Recombinant Piasmid Induced by X-irradiation and Its Mechanisms

Objective To study the effect of gene radiotherapy combining injection of recombinant plasmid pNEgr-mIL-12 with local X-irradiation on cancer growth and to elucidate the mechanisms of tumor inhibition. Methods Alkaline lysis was used to extract the plasmid and polyethylene glycol 8000 (PEG 8000) was applied for further purification of plasmids. Enzyme-linked immunosorbent assay (ELISA) was used to detect the expression of IL-12 protein. C57BL/6J mice were subcutaneously inoculated with B16 melanoma cells and the plasmid was injected directly into the tumor. Gene-radiotherapy combining pNEgr-mIL-12 recombinant plasmid with X-irradiation was given three times to C57BL/6J mice bearing B16 melanoma. Changes in immunologic parameters of tumor-bearing mice were detected with relevant immunologic assays. Results Results showed a significant decrease in tumor growth rate (P<0.05-0.001) after 3 times of gene-radiotherapy with IL-12 and X-irradiation. Immunologic studies showed a significant increase in CTL and N     

Early Embryonic Development in Vitro Co-cultured with Different Somatic Cells in Mice

The effect of different somatic cell cultures on mouse embryo development at early cleavage stage in vitro was studied.Oviductal epithelial,cumulus,uterine of fibroblast cells were co-cultured with mouse embryos respectively for 4 days,Embryos at 1-cell stage were collected from swollen ampullae of the oviducts.A total number of 121,111,132 and 89 embyos were co-cultured with oviduct epithelial,cumulus,uterine and fibroblast cells respectively,Among them,109,88,101 and 20 embryos developed regularly to the blastocyst stage respectively.The blastocysts were transferred to the uteri of synchronized recipient mice,only 9 blastocysts co-cultured with oviductal epithelial cells and 6 blastocysts with cumulus cells had developed normally and been implanted.These data indicated that oviductal epithelial cells and cumulus cells exert a specific promoting action on early embryonic development in vitro.     

Protective Effects of LAK Cells on Mice Subjected to Viral Infection

We employed LAK cells for anti-virus study and first successfully showed the protective effects of LAK cells on BALB/C mice subjected to lethal infection of herpes simplex virus type 1 (HSV-1). Two doses of LAK cells(3×10~7 cell/mouse) were injected i.v.into the mice which had been inoculated i.p. with     

Transgenic mice with overexpression of human scavenger receptor A on endothelial cells

Objectives To establish a new transgenic mouse model for determining the function and role of human scavenger receptor A (SR- A) in atherosclerosis in vivo. Methods Human scavenger receptor minigene- driven mouse tie- 1 promoter was constructed and confirmed by endonuclease digestion and sequence analysis. Transgenic mice were generated via the microinjection method. PCR and Southern blot were used t o screen the positive transgenic mice. RT- PCR and immunohistochemical analysis were used to detect the level and location of human SR- AⅠ expression in transgenic mice. The activity of human SR- AⅠ was determined by morphologi c observation of aortic endothelial cells of transgenic mice under transmission electron microscopy. Results The electrophoresis assay showed the expected 4 fragments of 0. 9 kb, 1. 1 kb, 1. 2 kb and 4. 2 kb in the SmaⅠ digest and 2 fragments of 0. 8 kb and 6 . 7 kb in BglⅡ digest of plasmids pTie- 1/hSR- A. The fragment sequence of tie - 1 p romoter and human SR- A cDNA in plasmids pTie- 1/hSR- A was correct and no A TG b efore the translation initiation sites of human SR- A was found by sequence ana lysis. 561 injected and surviving embryos with the purified human SR- A minigen e were implanted into the oviducts of 19 ICR pseudopregnant mice. Among the 54 surviving pups from 13 foster mothers, 7 were identified by PCR and Sou thern blot analysis. The results of RT- PCR and immunohistochemical analysis sh owed human SR- A was specifically expressed on vascular endothelial cells of the aorta and renal artery, as well as hepatic sinusoidal endothelial cells in tran sgenic mice. Transmmion electron microscope (TEM) of aorta of transgenic mice s howed that a large number of vesicles, multivesicle bodies and swollen mitochond ria filled the plasma of endothelial cells. Conclusions A transgenic mouse model with overexpression of human SR- A in endothelial cells was successfully established. The transgene was integrated and transmitted int o the chromosome of transgenic mice. Tie- 1 promoter controlled the transgene t o express in endothelial cells in mice. Pinocytic activity of aortic endothelia l cells in transgenic mice was higher than that of C57BL/6J mice. Our studies w ill provide a new transgenic model for investigation of atherosclerosis and func tions of human SR- A.     

Two new human exocrine pancreatic adenocarcinoma cell lines in vitro and in vivo.

Two human pancreatic carcinoma cell lines, PC-1 and PC-2, were established from nude mice xenografts derived from metastatic pancreatic carcinomas of two patients. The two cell lines propagated continuously in vitro over 19 and 19.5 months. The cells grow in a monolayered sheet with doubling times of 47 hours for PC-1 and 58 hours for PC-2. The cells exhibited epithelial morphology and were confirmed to be malignant epithelial cell lines by morphological study, CEA and cytokeratin immunocytochemistry, flow cytometry and Con A test. The tumors caused by inoculation of cultured PC-1 and PC-2 into nude mice retained the histological and ultrastructural features of the original tumors. The findings proved that the two cell lines were human exocrine pancreatic adenocarcinoma cell lines. Chromosomal analysis together with flow cytometry data revealed that the two cell lines had the human aneuploid karyotypic features with model chromosome numbers of 48 and 66.

     

无bFGF条件下简便有效建立C57BL/6J小鼠胚胎干细胞系

目的:在不含bFGF的Knockout血清替代品(knockout serum replacement,KSR)的培养条件下,简便、有效地建立小鼠胚胎干细胞(embryonic stem cells,ES)系.方法:以C57BL/6J小鼠3.5天囊胚为材料,改良巴氏德管机械法分离内细胞团,于加或不加碱性成纤维细胞生长因...     

瞬时性受体电位通道香草酸受体亚型6基因敲除小鼠模型的建立

目的 建立Trpv6基因剔除小鼠模型,为在体研究Trpv6的生物学功能及其与骨代谢关系创造条件。 方法 从Ensembl数据库中获得小鼠Trpv6基因组序列。设计基因剔除策略,构建基因剔除载体pBR322-MK-Trpv6。以电穿孔方法将基因剔除载体导入ES细胞,用G418和Ganciclovoir进行正负筛选,获得双抗性克隆。PCR鉴定出正确同源重组的胚胎多能干细胞（ES细胞）克隆。将正确同源重组的ES细胞注射到C57BL/6J小鼠的囊胚中,获得嵌合体小鼠。挑选嵌合率在50%的雄鼠与C57BL/6J小鼠交配,获得的灰鼠,PCR鉴定为杂合子小鼠。杂合子小鼠交配后获得纯合子小鼠。 结果 成功构建了打靶载体pBR322-MK-Trpv6。电穿孔后,共获得24个正确同源重组的克隆,同源重组效率为25%。同源重组的克隆经显微注射后,共获得4只嵌合率大于50%的雄鼠。嵌合鼠与野生型C57BL/6J交配,获得57只来源于ES细胞的灰鼠,PCR鉴定证实17只为杂合子小鼠,阳性率为33.3％。杂合子小鼠交配获得纯合子小鼠。经Western印迹证实纯合子小鼠无Trpv6蛋白的表达。 结论 已成功建立了Trpv6基因剔除小鼠模型,其中纯合子小鼠未出现胚胎致死现象。     

不同小鼠品系囊胚受体对C57BL/6胚胎干细胞种系嵌合效率的影响

目的 为了考察不同品系的小鼠囊胚对C57BL/6胚胎干细胞种系嵌合效率的影响，进而提高通过在C57BL/6胚胎干细胞中同源重组制作基因打靶小鼠的效率。 方法 本研究除了选取近交系B6(Cg)-Tyrc-2J和BALB/c品系，还选了封闭群ICR作为囊胚供体鼠，通过在TLX3、Ai3K和SL三个不同基因修饰ES细胞的种系嵌合实验中，平行比较三者的囊胚利用率、嵌合鼠获得效率以及种系遗传效率等三个方面，并进一步针对囊胚来源这一因素对效率的影响进行统计学分析。 结果 本研究中三种ES细胞均未能通过B6(Cg)-Tyrc-2J品系囊胚的注射获得种系遗传。而BALB/c品系与ICR品系相比，囊胚利用率明显低于ICR品系（P< 0.05）；嵌合鼠获得效率方面，BALB/c与ICR相当（P= 0.115）；而种系遗传效率方面，BALB/c品系显著高于其他品系（P< 0.01）。 结论 BALB/c品系在C57BL/6胚胎干细胞种系嵌合效率方面确实具有优势，然而，由于BALB/c囊胚较难获得，并且存在发育延迟和透明带脆性高等问题，而ICR品系在囊胚获得和利用方面的效率明显高于BABL/c，并且也可以支持C57BL/6胚胎干细胞的种系遗传，因此也是C57BL/6胚胎干细胞囊胚注射中较好的选择。     

小鼠胚胎干细胞的分离培养与鉴定

目的:培养、分离和鉴定C57BL/ 6小鼠胚胎干细胞(embryonic stem cell ,ESC).方法:收集小鼠3.5 d 的囊胚进行培养,用小鼠胚胎成纤维细胞作为饲养层,形成的ESC样集落,经两次亚克隆法分离培养成ESC;进行相差显微镜观察,采用阶段特异性胚胎抗原-1 (stage-spesific embryonic antigen,SSEA-1)对培养的ESC进行免疫组化染色. 结果:获得了稳定的ESC集落,传至第12代.ESC呈集落样生长,SSEA-1免疫组化染色强阳性.结论:两次亚克隆法获得的细胞具有ESC主要的生物学特性.     

人胚胎干细胞系的初步建立

目的：探讨人受精卵建立人胚胎干细胞系。方法：将体外受精获得的人受精卵发育至胚胎泡期,用机械法去除胚泡透明带后,取出内细胞团,分散后接种在小鼠胚胎成纤维细胞饲养层上,进行传代培养。通过碱性磷酸酶染色、胚胎干细胞特异性表面标志物检测、染色体核型分析和严重联合免疫缺陷（SCD）小鼠体内畸胎瘤形成实验,对连续传代的细胞进行鉴定。结果：9枚受精卵在体外培养5-7d后,5个存活并发育为胚泡,取出的内细胞团经接种培养,3个内细胞团存活,呈克隆性生长,发育为胚胎干细胞,并连续体外传代7个月保持未分化状态,建系成功。3个细胞系分别命名为CHE1、CHE3和CHE3。取3个细胞系第5、15和30代的细胞进行碱性磷酸酶染色,均为阳性。对CHE3第25、30、40代、CHE1和CHE2第21、22、30代的细胞检测人胚胎干细胞表面标志SSEA-4、SSEA-3、TRA-1-60和GCTM-2,结果均为阳性;检测小鼠胚胎干细胞表面标志SSEA-1,结果为阴性。染色体核型分析为二倍体核型。将连续传代5个月后（30代左右）的3个细胞系接种到SCID小鼠体内,6周后均形成畸胎瘤,组织病理学检查显示含有3个胚层的组织结构。结论：使用5个人受精卵来源的胚泡,成功地在体外建立了3个胚胎干细胞系,长期传代后仍保持胚胎干性和多向分化的能力。     

Rtn4-A/B基因敲除小鼠模型的制备

目的通过制备Rtn4-A/B基因敲除小鼠,探索Rtn4-B基因的生物学功能。方法用细菌人工染色体(BAC)载体构建Rtn4-A/B基因打靶载体并使其线性化,通过电转化法将其转入129SvEv品系雄性小鼠胚胎干细胞(embryonic stem cell,ES细胞)。将正确同源重组的ES细胞注射入C57BL/6J小鼠囊胚腔,繁育出嵌合体小鼠后,进一步繁殖以获得杂合子小鼠。抽提小鼠尾尖组织DNA,采用PCR法鉴定小鼠的基因型。结果基因打靶后,得到14个发生双臂正确同源重组ES细胞克隆。利用阳性ES细胞克隆进行囊胚内显微注射,得到5只嵌合率大于50%的雄鼠,最终繁育得到4只Rtn4-A+/-B+/-杂合子小鼠。结论利用ES细胞基因打靶、同源重组等方法,成功获得Rtn4-A/B基因敲除杂合子小鼠。     

ICR小鼠胚胎成纤维细胞的培养及饲养层的制作

目的：建立ICR小鼠胚胎成纤维细胞饲养层培养体系，用于胚胎干细胞建系及研究。方法：选取不同胎龄的鼠胚原代细胞分离成纤维细胞，制作饲养层，使用不同浓度丝裂霉素C处理，以细胞形态、生长曲线、囊胚种植情况为饲养层评价指标。结果：ICR小鼠胚胎成纤维细胞可在胎龄12．5～14．5d进行原代细胞分离；12．5d为最佳分离时间；13．5和14．5d分离的细胞需在3代以后使用；6代以前细胞可用于饲养层制作；20mg/L丝裂霉素C作用2．5h可达到较好的处理效果。结论：ICR小鼠可用来分离、培养胚胎成纤维细胞，用于胚胎干细胞饲养层的制作。     

应用顺铂建立C57小鼠感音神经性聋模型的实验研究

目的探讨顺铂诱发C57小鼠感音神经性聋模型的制备方法。方法将C57BL／6J小鼠随机分成4组,A组：耳蜗圆窗龛生理盐水给药5μL;B组：耳蜗圆窗龛顺铂给药5μL（1mg／mL）;C组：经鼓膜中耳腔顺铂给药10μL／d×5d（1mg／mL）;D组：腹腔注射顺铂6mg／（kg·d）×5d。用全频程脑干听觉诱发电位（ABR）检测4个组动物的听觉反应阈为指标,以动物各频率听觉反应阈上升≥10dB定为听力减退,并通过异硫氰酸荧光素（FITC）标记的鬼笔环肽染色观察用药后毛细胞的形态学变化。结果A、C、D组ABR反应阈用药前后无明显变化（P〉0．05）;B组小鼠顺铂用药后48h全频程ABR反应阈均升高（P〈0．05）,且毛细胞出现损伤、脱落,其损伤从顶回到底回有逐渐加重的趋势,外毛细胞较内毛细胞损伤严重。结论圆窗龛给药途径是建立顺铂诱发C57小鼠耳聋模型的有效途径。     

来源于胚胎干细胞的嵌合体小鼠自发性肿瘤观察

目的观察胚胎干细胞(ES细胞)囊胚腔注射的方法构建嵌合体小鼠自发性肿瘤。方法连续80周每周观察嵌合体小鼠的肿瘤发生情况,选取同龄相关品系小鼠各10只作为对照组。处死发生肿瘤的小鼠并且病理学检查,提取肿瘤组织的基因组DNA,用PCR方法检测性别决定区(SRY)基因判断肿瘤的品系来源。结果13只嵌合体小鼠中有3只(全为雌性)发生自发性肿瘤,分别为腺癌、皮下恶性畸胎瘤、淋巴瘤。肿瘤细胞来源于注射的ES细胞而非受体囊胚。对照组野生型小鼠未见肿瘤发生。结论ES细胞囊胚腔注射的方法构建嵌合体小鼠具有较高的自发肿瘤发生率,可作为自发性肿瘤动物模型。