In vitro phenotypic characterization of human limbal epithelial cells

INTRODUCTION: Human limbal epithelial cells (huLEC) have been used for clinical purposes in ocular surface diseases to promote rapid re-epithelisation and restore corneal epithelium integrity. However, in Mexico this technique has not been fully developed. This study was conducted to characterize the huLEC phenotype expanded in vitro using a cell culture technique. MATERIAL AND METHODS: Cells were obtained from limbal tissue, cultured in KSFM medium and analyzed for the expression of vimentin, K, K19, p63, K12, by flow cytometry and immuno-fluorescence. RESULTS: The phenotype of cultured cells was vimentin+K+K19+ p63+K12-. CONCLUSIONS: Our results suggest that under these culture conditions huLEC maintained their stem cell phenotype. This culture technique could be used for clinical purposes in Mexico.     

In vitro culture of human thymic epithelial cells in serum-free media

Epithelial cells from human thymus were cultured in vitro at various serum concentrations and under defined serum-free conditions. A total of 238 cultures from 46 thymuses (MG and normal) were analyzed. Cells from fresh thymic tissue were explanted either as fragments or single cells after enzyme treatment. Serum-free as well as fetal calf serum (FCS) containing media based on Dulbecco's minimal essential medium and Ham's F-12 (DMEM/F-12) were found to be superior to MCDB 151 based serum-free media combinations, for the selective growth of thymic epithelial cells. In contrast, cultures based on RPMI 1640 medium supplemented with 1% FCS or more showed less epithelial cell selectivity and also supplement Ultroser G gave less fibroblast contamination. In serum-free media containing less than 0.1 mM ionic Ca, the cells had a smaller surface area and appeared more angular and also contained less keratin as compared to culture media with higher calcium contents. The development of serum-free conditions for in vitro growth of human thymic epithelial cells free of fibroblast contamination will facilitate studies of growth and maturation of the epithelial cells as well as investigations of their possible role in the development of myasthenia gravis.     

Serial culture of adult human prostatic epithelial cells

Summary Techniques for the isolation, establishment, and subculture of normal, benign hyperplastic and malignant epithelial cell cultures from adult human prostates are described. Acini are released from tissues by collagenase digestion, and primary and subcultures are grown in collagen-coated dishes containing medium PFMR-4A supplemented with 1% serum and additional factors. Growth assays can be performed in serum-free medium. Verification of the cultures as prostatic epithelial cells is accomplished by indirect immunofluorescence detection of keratin, prostate-specific antigen, and prostatic acid phosphatase.     

新型隐球菌与肺泡上皮细胞的体外相互作用

目的研究新型隐球菌与肺泡上皮细胞的体外相互作用,探讨隐球菌肺部感染的发病机制。方法体外培养Ⅱ型肺泡上皮细胞A549(ATCC CCL-185),检测新型隐球菌2种变种对细胞的时间/浓度黏附率、通过率;检测新型隐球菌对细胞的损伤作用;透射电镜观察相互作用的超微结构。结果2种变种的新型隐球菌可以对A549细胞产生黏附与侵袭,黏附率与侵袭率呈现时间依赖性;同时还可以使A549细胞凋亡率升高,对其造成损伤,这与菌体的活力相关。超微结构可见隐球菌与肺泡上皮细胞的黏附与侵袭过程。2种变种之间在黏附率、通过率及对细胞的损伤作用方面差异无统计学意义。结论活的隐球菌黏附与侵袭肺泡上皮细胞是隐球菌感染肺部的重要条件,不同变种对肺部的易感性可能不存在差异。进一步明确二者的作用机制对隐球菌的发病机制研究具有重要意义。     

EB病毒对人胚鼻咽上皮细胞的转化

为观察EBV和／或促癌物四癸酸佛波醇二酯（TPA）对其的转化作用，以人胚鼻咽上皮作体外原代组织培养，采用自B95－8细胞分离的EB病毒直接感染或结合TPA处理体外培养的人胚鼻咽上皮细胞，着重观察感染细胞在半固体培养基中的集落形成率；并采用PCR扩增法探讨EB病毒是否直接进入鼻咽上皮细胞。结果显示：单独EB病毒或灭活（56℃，30分钟）EB病毒加TPA感染时，病毒不能进入细胞导致表型改变；活性EB病毒结合TPA同时处理或先用EB病毒后用TPA处理时，EB病毒能直接进入细胞并导致细胞集落形成率明显增高（P＜0．05）。从而表明EB病毒体外能部分转化人胚鼻咽上皮细胞，其转化作用依赖于TPA的存在和病毒基因组的完整。     

In vitro studies on endometrial adhesiveness for trophoblast: cellular dynamics in uterine epithelial cells

Initiation of embryo implantation involves adhesion of trophoblast cells to the epithelial lining of the endometrium. The mechanisms regulating the adhesive properties of the uterine epithelium for trophoblast during initiation of human embryo implantation, however, are still incompletely understood. We report here on model studies that we have performed in our laboratory, and in particular on certain methodological approaches that seem to yield new insight into basic mechanisms involved. Of central interest is the ability of the uterine epithelium to develop an adhesion competence at its apical cell pole. This confronts us with a cell biological paradox in that adhesion must be established at the pole which in simple epithelia is typically specialized to resist adhesion. Gain of apical adhesion competence by uterine epithelial cells should be related to cellular rearrangements, i.e. a modulation of their apicobasal cell polarity. Here, we used monolayer-cultured uterine epithelial RL95-2 cells as an in vitro model for the human receptive uterine epithelium. We demonstrated that formation of stable cell-to-cell bonds between the free (apical) pole of these cells and attaching trophoblast (modelled by JAr cells) depends on a number of structural and functional peculiarities that RL95-2 cells have in contrast to other uterine epithelial cells (HEC-1-A cells) which resist attachment via this cell pole. RL95-2 cells were shown to lack tight junctions and to exhibit only rudimentary adherens junctions and a non-polar organization of the actin cytoskeleton. Using the atomic force microscope in a force spectroscopy mode, we exactly defined the time dependence of adhesive interactions between RL95-2 cells and trophoblast, measured the pressure force needed to initiate this process, and screened the buildup of the adhesive forces between the binding partners. A dynamic interaction between the actin cytoskeleton and integrins (a prerequisite for functional activity of integrins) was shown to be an important aspect of the adhesive properties of RL95-2 cells. In addition, at least two types of calcium channels in the plasma membrane of RL95-2 cells seem to play a role in activation of a variety of calcium-sensitive response mechanisms including adhesiveness for trophoblast, i.e. diltiazem-sensitive channels seem to contribute to the initiation of JAr cell binding and SKF-96365-sensitive channels to participate in a feedback loop that controls the balance of bonds. By extrapolation, these data suggest an active role of the uterine epithelium in the process of embryo implantation which we are just beginning to understand in terms of its cell biology.     

In vitro replication of varicella-zoster virus in human retinal pigment epithelial cells

Here we describe for the first time the productive in vitro infection of human retinal pigment epithelial cells by varicella-zoster virus (VZV), resulting in a typical cytopathic effect (CPE) that is characterized by enlarged cells with increased granularity. Depending on the CPE dissemination, high titers of up to 1.6 x 10(6) PFU of cell-free and cryostable VZV/ml can be recovered.     

改良组织块培养法体外培养人角膜上皮干细胞

文题释义：角膜上皮干细胞：属于单能干细胞,具有细胞周期长、低分化状态、增殖潜力大、不对称分裂等特点,定位于角膜缘基底细胞层,又称之为角膜缘干细胞,对角膜上皮细胞更新及维持角膜透明起着重要作用。角膜缘干细胞的体外培养方法：主要包括酶消化培养法和组织块培养法。酶消化培养法是利用DispaseⅡ酶破坏角膜缘上皮细胞与基底膜之间的半桥粒连接,然后剥取角膜缘上皮层,再使用胰酶将其消化为单个细胞进行培养。组织块培养法没有经过酶的双重消化,将剖取的角膜缘组织块进行贴壁,细胞游离出组织块进行贴壁生长,需要一个漫长的过程。  摘要背景：角膜上皮干细胞定位于角膜缘,又称之为角膜缘干细胞,临床上由于眼表严重热烧伤、化学性烧伤、慢性炎症等原因引起的角膜缘干细胞缺乏或功能障碍治疗较为棘手。目前利用组织工程技术体外培养角膜上皮干细胞并进行临床移植成为新型有效的治疗方向。目的：探讨在无血清培养条件下采用改良组织块培养法培养人角膜上皮干细胞的可行性。方法：人角膜缘组织来自河南省眼库,植片直径小于8 mm角膜移植术后的供者剩余眼球材料,手术显微镜下剖取角膜缘上皮层外2/3区域,采用2种方法培养人角膜上皮干细胞,常规组织块培养组是将组织块上皮面向上贴壁,加入K-SFM培养液后置于 37 ℃、体积分数为5%CO₂细胞培养箱中培养;改良组织块培养组是先将组织块浸泡于K-SFM培养液中,置于细胞培养箱中孵育12 h,然后组织块上皮面向下贴壁培养。组织块周边有细胞游离出贴壁生长记作“培养第1天”,每日相差显微镜下观察细胞生长变化。利用免疫荧光染色技术检测改良组织块培养第5,10,14天时原代细胞中p63及K3的表达。结果与结论：①改良组织块培养组出膜时间明显短于常规组织块培养组(P < 0.05),出膜率明显高于常规组织块培养组(P < 0.05);②改良组织块培养组细胞生长状态良好,培养第10天可见小体积细胞较多,聚集成灶状分布;培养第14天可见细胞克隆灶,克隆灶内细胞体积较小,形态均一;③培养第5天,K3表达量较多,p63表达量较少;培养第10天,K3和p63表达量均增多;培养第14天,K3表达量未见明显增多,p63表达量明显增多;④在无血清培养条件下,改良组织块培养法能显著促进角膜上皮干细胞的游离,提高体外培养细胞数量,为人角膜缘上皮组织片的构建提供种子细胞。ORCID: 0000-0001-8370-174X(许中中) 中国组织工程研究杂志出版内容重点：干细胞;骨髓干细胞;造血干细胞;脂肪干细胞;肿瘤干细胞;胚胎干细胞;脐带脐血干细胞;干细胞诱导;干细胞分化;组织工程     

In vitro culture of human epithelial cells on a modified xenogenic collagen support

Human epithelial cells (HeLa, HaCaT, NHK) were cultured in vitro on chemically modified collagen membranes. Adhesion to the support was measured by estimation of the percentage of adhering 51Cr-labeled cells. Proliferation was estimated with the XTT test. Morphological observations of cells growing on HCl-treated collagen were performed using histological and electron microscopic techniques. HCl and trypsin-modified xenogenic collagen was found to be a good support for human cells in vitro. EDTA-incubated collagen enhanced neither adhesion nor proliferation. The best adhesion and proliferation were found on HCl-treated collagen, depending, however, on the kind of cells.     

周期性机械牵张对人肺泡上皮细胞穿透素-3表达的影响

目的探讨人肺泡上皮细胞穿透素-3(PTX3)在呼吸机相关性肺损伤中的可能作用。方法应用FX4000T细胞应变加载系统,对体外培养的人肺泡上皮细胞A549周期性施加20%应变,频率为0.3Hz,加载时间为1、2、4、6h,然后采用实时定量RT-PCR检测肺泡上皮细胞PTX3表达的变化、Western blot检测分泌到培养液上清PTX3蛋白,同时检测细胞活性。结果(1)周期性牵张诱导肺泡上皮细胞表达PTX3;(2)牵张引起肺泡上皮细胞的凋亡;(3)PTX3的水平与肺泡上皮细胞的凋亡水平显著相关。结论本研究提示PTX3在呼吸机相关性肺损伤的发病机制中可能起重要的作用。     

In vitro studies of human pituitary adenomas

The application of morphologic and tissue culture techniques to the study of human pituitary adenomas allows further investigation of structure-function correlations. Using these methods, we have documented morphometric differences between densely and sparsely granulated somatotroph adenomas but the release of growth hormone in vitro and responses to adenohypophysial hormones/drugs do not correlate with tumor type. The morphologic and functional alterations in somatotroph adenomas exposed to SMS 201-995 appear to be reversible in vitro. Incubation of lactotroph adenomas with bromocriptine for 3 days directly reduces tumor cell size, cytoplasmic volume and cytoplasmic volume densities of endoplasmic reticulum and Golgi regions; these changes are similar to the effects of longterm bromocriptine therapy in vivo. Tissue culture studies of gonadotroph adenomas of men confirm that gonadotropin-releasing hormone (GnRH) stimulates gonadotropin release by tumor cells and yields morphologic evidence of increased hormone synthesis whereas these tumors have variable sensitivity to gonadal steroids; structural changes in tumor cells correlate with hormone release after stimulation, suggesting that morphologic parameters may reflect the hormonal milieu of these adenomas. Null cell adenomas and oncocytomas release small quantities of glycoprotein hormones, predominantly gonadotropins in vitro and there are no functional differences between these 2 tumor types; gonadotropin release responds to GnRH stimulation and, paradoxically, to other adenohypophysiotropic hormones, but such stimulation does not result in secretion of other adenohypophysial hormones by these tumors.     

Use of monoclonal antibodies to identify thymopoietin in cultured human thymic epithelial cells.

Murine monoclonal antibodies (mAbs) were developed to discriminate thymopoietin, a human thymic hormone, and thysplenin, a closely related molecule found in spleen. Three of these recognized both native and synthetic thymopoietin as well as thysplenin. Together they define two non-overlapping epitopes which withstand sodium dodecyl sulfate denaturation and can be detected by western blotting. We used these three mAbs to demonstrate the production of thymopoietin by cultured thymic epithelial cells for up to several weeks. Three additional mAbs were selective for thysplenin. Highly specific mAbs will be useful for characterizing further these physiologically distinct polypeptides.     

Adherence of Helicobacter pylori to human gastric epithelial cells in vitro

Gram-negative spiral organisms, currently referred to as Helicobacter pylori, are associated with primary gastritis and duodenal ulceration. The organisms colonise gastric mucus and adhere to epithelial cells of inflamed antra. To further examine the binding of H. pylori to human gastric epithelial cells, we developed and characterised an in-vitro bacterial adherence assay. Scanning electronmicroscopy suggested that spiral-shaped bacteria were adherent to the surface of KATO-III cells which were derived from a human gastric adenocarcinoma. Transmission electronmicroscopy confirmed the attachment of H. pylori to these epithelial cells in tissue culture. Some bacteria were adherent to intact microvilli, others were closely adherent to the plasma membrane in regions where microvilli were effaced. In studies with radiolabelled H. pylori, adherence to epithelial cells in tissue culture contrasted with minimal binding of bacteria to polystyrene wells alone. Incubation of bacteria with gastric cells at 4 degrees C significantly reduced adherence of H. pylori. We conclude that adherence of H. pylori to gastric epithelial cells in tissue culture involved "attachment and effacement mechanisms". This assay could serve as a suitable in-vitro model for the study of the bacterial adhesins and host receptors which mediate attachment of H. pylori to gastric epithelial cell surfaces.     

人支气管上皮细胞的体外培养

背景：人支气管上皮细胞培养在呼吸系统疾病研究中应用越来越广泛。 目的：探索美国典型培养物保藏中心人支气管上皮细胞体外培养方法的可行性。 方法：对人支气管上皮细胞培养条件进行反复摸索,最终确定应用含体积分数20%胎牛血清的DMEM/F12培养基进行培养。 结果与结论：实验培养的人支气管上皮细胞扁平,呈多边形,长满后呈“铺路石”样分布,经免疫组化检测发现培养的细胞表达上皮细胞标志物细胞角蛋白。在支气管扩张症患者痰液上清刺激下,细胞表达的核因子κB、肿瘤坏死因子α和白细胞介素8明显增强,证实培养的人支气管上皮细胞获得成功。提示不必拘泥于美国典型培养物保藏中心推荐的培养条件,改进的培养方法简便易行,有应用价值。     

In vitro studies of amikacin-loaded human carrier erythrocytes

Erythrocyte-encapsulated antibiotics have the potential to provide an effective therapy against intracellular pathogens. The advantages over the administration of free antibiotics include a lower systemic dose, decreased toxicity, a sustained delivery of the antibiotic at higher concentrations to the intracellular site of pathogen replication, and increased efficacy. In this study, the encapsulation of amikacin by human carrier erythrocytes prepared using a hypo-osmotic dialysis was investigated. The effects of the initial amikacin dialysis concentration and hypo-osmotic dialysis time on the encapsulation efficiency of amikacin were determined, and the osmotic fragility and hematologic parameters of amikacin-loaded carrier erythrocytes were measured. The efficiency of amikacin entrapment by carrier erythrocytes was dependent on the initial dialysis concentration of the drug. Statistically significant differences in the osmotic fragility profiles between control and carrier erythrocytes were observed, which were dependent on the hypo-osmotic dialysis time and on the dialysis concentration of amikacin. Mean hematologic parameters were evaluated and compared with unloaded, native erythrocytes; the mean corpuscular volume (MCV) of amikacin-loaded carrier erythrocytes was statistically significant smaller. Amikacin demonstrated a sustained release from loaded erythrocytes over a 48-h period, which suggests a potential use of the erythrocyte as a slow systemic-release system for antibiotics.     

In vitro studies of human seminal plasma allergy

A 23-yr-old woman experienced generalized urticaria, angioedema, and respiratory obstruction after intercourse. Reactions increased in frequency and severity over a 2-yr period; sexual exposures were limited to her husband. Fresh, centrifuged seminal plasma samples from four donors, including her husband, evoked positive immediate puncture skin-test reactions in dilutions of 1:100 or 1:1,000; no reactions were seen in normal control males. A borderline elevation in serum IgE antibodies to seminal plasma was noted by the radioallergosorbent test (RAST). However, the patient had elevated IgE antibodies to a partially purified seminal plasma fraction (IV) obtained by Sephadex G-200 gel filtration. Seminal plasma from all four donors showed similar allergenic activity when tested in fraction IV RAST inhibition experiments. Further in vitro studies have characterized the allergenic components infraction IV. Allergenic components (pool III) (1) are distinct from acid phosphatase; (2) have an apparent molecular weight range from 20,000 to 30,000 daltons; (3) by isoelectrofocusing produced multiple bands with pi of 6.6, 7.0, and 7.5; and (4) produced multiple bands in polyacrylamide gel electrophoresis, indicating a heterogeneous group of antigens. Comparison of pool III with seminal vesicle secretions and prostatic homogenate via thin-layer isoelectrofocusing revealed protein bands which appeared to be common to all three materials. Thus, it remains uncertain as to whether allergenic proteins are derived from seminal vesicle or prostatic secretions. Condom usage by the patient's husband has essentially prevented subsequent allergic reactions. However, serum IgE antibodies to fraction IV remained consistently elevated during a 28-mo follow-up period.     

In vitro response of human T cells to Pseudomonas aeruginosa

Pseudomonas aeruginosa is a gram-negative bacillus that is a major cause of morbidity and mortality in immunosuppressed patients, burn patients, and patients with cystic fibrosis. Although immunity to these bacteria has been associated with serum antibody, more recent evidence suggests that T-cell-mediated immunity may also be important. To evaluate human T-cell responsiveness to these bacteria, the optimal conditions were determined for in vitro proliferation of human peripheral blood lymphocytes and T-lymphocytes to Fisher-Devlin immunotype 1 P. aeruginosa. The proliferative response of normal adult peripheral blood lymphocytes to heat-killed P. aeruginosa was studied in 34 subjects (range, 7,600 to 111,500 net cpm). Analysis of cell subpopulations indicated that T-lymphocytes are the major proliferating cells and that this response is enhanced by the presence of adherent cells. Data from fetal cord lymphocyte responses suggest that the proliferation seen in normal adult lymphocytes is induced by antigenic and not mitogenic stimulation.