2种气管黏膜上皮细胞体外培养技术的研究

目的为以猪气管黏膜上皮为细胞模型的研究奠定物质基础,进一步探讨猪气管黏膜上皮细胞的体外传统培养和气液界面培养技术,从而使2种培养技术优势互补。方法对猪气管上皮分离、纯化、培养和传代,并探索上皮细胞最佳冻存复苏条件;复苏后的气管上皮细胞进行气液界面培养,绘制细胞生长曲线和观察细胞纤毛生发情况。利用免疫组化法鉴定上皮细胞。结果4步纯化法可以得到高纯度的气管上皮细胞。使用胎牛血清、DMEM/F12培养液和DMSO的体积分数为50%、40%和10%的冻存体系保存的气管上皮,复苏后细胞存活率平均可达89%。优化后的传统方式培养的上皮细胞可连续传代到第8代,但从第2代开始便观察不到纤毛,转换成气液界面连续培养2代后重新生发纤毛,细胞存活期延长。免疫组化结果显示分离培养细胞为上皮细胞。结论成功建立了2种猪气管上皮细胞培养技术,并找到适宜的气管上皮细胞冻存条件,节省了不断原代取材的成本和时间,并成功实现传统培养细胞冻存复苏后很快适应气液界面的培养并恢复细胞的天然结构,为猪气管黏膜上皮相关研究提供丰富的细胞来源。     

动物细胞无血清培养技术研究进展

动物细胞培养技术建立在组织培养技术基础上,在技术方法、实际应用方面都得到全新发展。该文主要就培养基、工程细胞株、培养仪器和设备等几个重要方面进行综述。     

成人宫颈上皮细胞的原代培养及鉴定

目的:探索采用无血清培养基原代培养成人宫颈上皮细胞的方法。方法:以成人的宫颈上皮组织为研究对象,采用胰蛋白酶-EDTA消化法获得宫颈上皮细胞悬液,于上皮细胞专用无血清培养基中培养,采用免疫细胞化学法测定细胞中角蛋白及波形蛋白的表达,对细胞纯度进行鉴定。结果:原代培养10-15天细胞融合达60%,传代至4-6代,细胞出现生长衰退。早期细胞生长状态良好,细胞纯度在90%以上。结论:采用酶消化法及K-SFM无血清培养基培养可获得纯度高的成人宫颈上皮细胞。     

大鼠前列腺上皮细胞在无血清培养液中增殖的调节

本文报道了未成年大鼠前列腺上皮细胞的无血清培养模型的建立方法,并利用该模型研究了生长因子、催素及性激素对前列腺细胞增殖功能的作用。结果表明：胰岛素、表皮生长因子、转铁蛋白、霍乱霉素和牛垂体提取物对前列腺细胞的增殖有直接的促进作用,糖皮质激素对细胞的增殖无明显影响。催乳素刺激细胞的增值,但与双氢睾酮或雌二醇无协同作用。单独的双氧睾酮或雌二醇对细胞的增殖无显著作用。     

CHO工程细胞 (11G-S) 悬浮培养的无血清培养基的设计

以悬浮适应的表达重组尿激酶原 (Pro-urokinase,pro-UK) CHO工程细胞系11G-S为对象,采用Plackett-Burman实验设计及响应面分析法,设计支持CHO工程细胞 (11G-S) 悬浮生长的无血清培养基。以细胞密度为评价指标,在单因素实验的基础上采用Plackett-Burman实验设计对影响细胞生长的培养基添加成分进行考察,确定了3种对细胞生长明显促进作用的培养基添加成分：胰岛素、转铁蛋白及腐胺。继而利用响应面法分析了这3种添加成分的最佳水平范围,设计了一种适用于CHO工程细胞 (11G-S) 悬浮培养的无血清培养基SFM-CHO-S。11G-S细胞在SFM-CHO-S批次悬浮培养的细胞最大生长密度达到4.12×106 cells/mL,pro-UK的最大累积活性达到5 614 IU/mL,培养效果优于商品化的同类无血清培养基。     

呼吸道上皮细胞模型的研究进展

呼吸道病毒严重威胁人类的健康。呼吸道上皮细胞是机体防御呼吸道病毒和细菌等外来病原体的第一道防线,因此建立呼吸道上皮细胞体外分化模型,为研究呼吸系统疾病发病机理、筛选有效的治疗药物奠定基础。本文主要介绍人呼吸道上皮细胞原代培养技术的研究进展及其在呼吸道病毒和呼吸系统疾病方面的应用。     

小鼠和兔原代乳腺上皮细胞的培养

目的：对小鼠和兔的原代乳腺上皮细胞进行培养。方法：取小鼠和免的乳腺组织,用加葡萄糖的PBS稀释胶原酶Ⅲ作消化液、分三个阶段进行消化,选择离心后的小细胞团,用含激素的培养液培养。结果：在基本培养液中添加10ng／ml的表皮生长因子和5μg／ml的胰岛素可以使乳腺上皮细胞富集．结论：成功地培养出了小鼠和免的原代乳腺上皮细胞。     

无血清培养中小鼠神经母细胞瘤细胞老化的研究

本文报道应用倒置相差显微术和显微荧光光度术观察无血清培养条件对ＮＢＡ２细胞突起数目和细胞内脂褐素荧光值的影响,以建立神经细胞老化实验研究模型。结果发现：存在着随无血清培养天数的增加,细胞内脂褐素荧光值累积性增加（Ｐ＜０．０１）和培养５天后细胞突起数目渐次性减少（Ｐ＜０．０１）的趋势。结果表明：这一趋势与哺乳类动物和人类老化研究中的神经细胞内脂褐素含量随增龄而增加及神经细胞突起在衰老过程逐渐少消失的     

A new diploid nontumorigenic human breast epithelial cell line isolated and propagated in chemically defined medium

Summary A new, nontumorigenic human breast epithelial cell line, HMT-3522, has been established from fibrocystic breast tissue. Cells were explanted and propagated in chemically defined medium including insulin, transferrin, epidermal growth factor, hydrocortisone, estradiol, prolactin, and Na-selenite. The epithelial nature of the cell line was established by immunocytochemical detection of cytokeratins. Moreover, electronmicroscopy revealed monolayers of polarized cells connected by desmosomes and provided with apical microvilli. Milk fat globule membrene antigen, specific for the apical membrane domain of normal, luminal breast epithelial cells, was expressed only in confluent cultures where some cells overlaid others, indicating “stem cell”-like properties. After 25 to 30 passages, the cells are diploid with a few marker chromosomes and loss of chromosomes in the D-group. The cells are nontumorigenic in athymic mice; they lack estrogen receptors, and estradiol does not stimulate growth. The HMT-3522 cell line may represent a useful model for the study of brest cell differentiation and carcinogenesis in vitro. This work was supported by a grant from the Danish Cancer Society.     

Establishment of endometrial glandular epithelial cell subculture in a serum-free,hormonally defined medium,on a basement membrane matrix

Summary— Epithelial glands were isolated from guinea-pig endometrium. In order to reduce the requirement for a serum supplement and the contamination by non epithelial cells in primary culture, various coatings of the culture dishes were tested using serumfree Ham's F12 containing defined chemicals including 17β-estradiol. while epithelial glands seeded on culture dishes coated with Matrigel, a basement membrane matrix-failed to spread, they formed on poly-d -lysine plus serum-coated dishes, a subconfluent monolayer (5–7 days) enriched in cytokeratin-immunostained cells (78%). Cells from subconfluent primary cultures, obtained on poly-d -lysine plus serum-coated dishes in serum-free hormonally defined medium, were passaged on Matrigel-coated dishes in serum-free hormonally defined medium. These subcultures contained, at confluence (4–5 days), a high percentage (> 95%) of cytokeratin-immunostained cells. These monolayers consisted of well-differentiated cells which exhibited ultrastructural features characteristics of endometrial epithelial cells. Moreover, these confluent cells contained 50% immunostained nuclei for progesterone receptors. Progesterone receptor amounts decreased in confluent subcultures treated with progesterone and became undectable after longterm treatment, suggesting responsiveness of these cells to progesterone. This culture system provides a well-defined model for the study of protein synthesis and secretion by endometrial glandular cells under hormonal control.     

Continuous multiplication of rabbit tracheal epithelial cells in a defined,hormone-supplemented medium

Summary An improved Ham’s F12 nutrient medium supplemented with epidermal growth factor (EGF), insulin (INS), and transferrin (TF) was developed for continuous proliferation and clonal growth of primary rabbit tracheal epithelial (TE) cells in culture. The addition of small quantities of fetal bovine serum (FBS) (0.01 to 0.1%) to cultures had little measurable stimulation on TE cell growth and plating efficiency. However, serum levels higher than 0.1% inhibited cell growth and also masked the growth stimulating activities of EGF and INS despite an increase in cell attachment. Under this defined, hormone-supplemented medium, and in the presence of a trace amount of serum (0.01%), 10 to 20% of the protease-dissociated TE cells attached to the culture dish followed by at least four population doublings during 7 to 10 d of culture. Clonal growth occurred at a seeding density of 17 cells/cm² with a plating efficiency of 6 to 8%. Confluent primary cultures could be passaged two to four times by treatment with a 0.1% trypsin-1 mM EDTA solution and a total of 10 to 30 population doublings of in vitro life span were obtained. The epithelial nature of cultured cells was confirmed by indirect immunofluorescent staining with antikeratin antibody as well as by transmission electron microscopy. This study shows that using this improved hormone-supplemented medium, rabbit TE cells can be maintained in culture for extended periods of time without the aid of a fibroblast feeder layer or explant tissue. This system could be useful for the study of cell differentiation of tracheal epithelium.     

Serum-free culture conditions for the growth of normal rat mammary epithelial cells in primary culture

Summary A monolayer culture system has recently been developed for the extended growth and serial passage of normal rat mammary epithelial (RME) cells. In this system the cells undergo greater than 20 population doublings when grown on type I collagen-coated tissue culture dishes in Ham's F12 medium supplemented with insulin, hydrocortisone, epidermal growth factor, prolactin, progesterone, cholera toxin, and 5% fetal bovine serum (FBS). The purpose of the present studies was to define additional growth factors that would allow equivalent RME cell proliferation in serum-free medium. Ethanolamine (EA) was effective at reducing the FBS requirements for RME cell proliferation and at its optimum concentration did so by greater than 20-fold. Even with optimum levels of EA there was essentially no cell proliferation in the absence of FBS. However, addition of bovine serum albumin (BSA) to the hormone, growth factor, and EA-supplemented medium resulted in substantial proliferation in the absence of serum, and the further addition of transferrin (T) potentiated this effect. Thus, in this culture system, replacement of FBS with EA, BSA, and T resulted in RME cell proliferation in primary culture which was equivalent to that obtained in the 5% FBS-containing medium. This work was supported by grant RR-05529 from the Division of Research Resources, National Institutes of Health, Bethesda, MD, and by Public Health Service grant CA40064-01 from the National Cancer Institute, Bethesda, MD.     

Differentiation of mouse embryonic stem cells into dental epithelial-like cells induced by ameloblasts serum-free conditioned medium

Embryonic stem cells (ESCs) possess an intrinsic self-renewal ability and can differentiate into numerous types of functional tissue cells; however, whether ESCs can differentiate toward the odontogenic lineage is still unknown. In this study, we developed an efficient culture strategy to induce the differentiation of murine ESCs (mESCs) into dental epithelial cells. By culturing mESCs in ameloblasts serum-free conditioned medium (ASF-CM), we could induce their differentiation toward dental epithelial cell lineages; however, similar experiments with the tooth germ cell-conditioned medium (TGC-CM) did not yield effective results. After culturing the cells for 14 days in the differentiation-inducing media, the expression of ameloblast-specific proteins such as cytokeratin (CK)14, ameloblastin (AMBN), and amelogenin (AMGN) was markedly higher in mESCs obtained with embryoid body (EB) formation than in mESCs obtained without EB formation. We observed that immunocompromised mice implanted with induced murine EBs (mEBs) showed tissue regenerative capacity and produced odontogenic epithelial-like structures, whereas those implanted with mSCE monolayer cells mainly formed connective tissues. Thus, for the first time, we report that ASF-CM provides a suitable microenvironment for inducing mESC differentiation along the odontogenic epithelial cell lineage. This result has important implications for tooth tissue engineering.