共查询到20条相似文献,搜索用时 15 毫秒
1.
A. T. Hood D. Currie S. J. Garte 《In vitro cellular & developmental biology. Plant》1987,23(4):274-278
Summary A new cell line designated NAS 2BL has been established from a rat nasal tumor induced by inhalation of the direct-acting
carcinogen methylmethane sulfonate. The cells are epithelial in morphology, have a generation time of 34 h, require 10% fetal
bovine serum for optimal growth, and exhibit keratinization at confluence. The karyotype is aneuploid, with several marker
chromosomes, and the cells are transformed by the criterion of nude mouse turmorigenicity.
This work was supported by grants CA36342, ES03563 and Center grants ES00260 and CA13343, from the National Institutes of
Health; and Special Institutional grant 00009 from the American Cancer Society 相似文献
2.
T Itoh M Nakamura H Yagi H Soga H Doi S Koja M Nanno R Suzuki S Satomi S Kasahara 《Cellular and molecular biology, including cyto-enzymology》2001,47(1):1-18
Interactions between thymocytes and thymic stromal cells are essential for thymocyte differentiation, but little evidence has been presented to directly show in vivo functions or interactions of the stromal cells. Among the stromal cells, the thymic epithelial cell has been considered to have profound effect on thymocyte differentiation and maturation. The calcium-depleted medium, originally developed for the culture of mouse epidermal cells, was applied for the culture of the mouse thymic epithelial cells, and successfully, an epithelial cell line, IT-76MHC was obtained from the mouse thymus. IT-76MHC cells were identified as distinct mouse thymic epithelial cells by 1/ mosaic-like arrangement, 2/ presence of well-developed desmosome and 3/ tonofilaments, 4/ positivity for cytokeratin, and 5/ induced expression of MHC class I and II by IFN-gamma treatment. IGF-1, IGF-2, oxytocin and vasopressin were also detected immunohistochemically in IT-76MHC cells. Furthermore, the IT-76MHC thymic epithelial cells, when injected intrathymically in the allogeneic mouse, prolonged the survival of skin graft from the same donor strain that IT-76MHC cells were derived. These results demonstrate that the thymic epithelial cell line IT-76MHC produces modest thymocyte survival factors as well as a growth suppressor, and that IT-76MHC cells have the ability to induce transplantation tolerance probably through their expression of MHC class I and II molecules. Taken altogether, the IT-76MHC thymic epithelial cells have been proved to be useful tools to better understand the in vivo functions of thymic epithelial cells, and to gain a deep insight into their involvement in the critical selection process of thymocytes which still remains obscure. Finally and additionally, literatures so far reported on thymic epithelial cells in culture, especially lines and clones, are reviewed and their identity as well as their functions are discussed. 相似文献
3.
B. Borisch T. Kirchner A. Marx H. K. Müller-Hermelink 《Virchows Archiv. B, Cell pathology including molecular pathology》1990,59(1):359-365
It has previously been shown that the EpsteinBarr virus (EBV) genome may be detected in some thymic tumors. We have investigated
specimens of normal thymus, thymitis with lymphoid hyperplasia and a large spectrum of thymic epithelial tumors obtained from
european patients for the presence of EBV genome by in situ hybridization and DNA-blotting methods. Cell lines established
from seven of the thymic tumors were also tested for EBV. No EBV genome was demonstrated in any of the tumors examined, which
included various types of thymoma and thymic carcinomas, nor in the non-neoplastic thymic specimens. However, unlike previous
reports, no examples of lymphoepithelial-like thymic carcinoma, nor specimen from Asian patients were included in this study.
We suggest that EBV is linked to a specific epithelial tumor type, namely the lymphoepithelial-like carcinoma, regardless
of its site, and not to thymic tumors in general.
Supported by the SFB 172, C8, grant to BB and by the Deutsche Forschungsgemeinschaft, grant Ki 370/1-1 相似文献
4.
Development of the thymus requires signaling through the fibroblast growth factor receptor R2-IIIb 总被引:15,自引:0,他引:15
Revest JM Suniara RK Kerr K Owen JJ Dickson C 《Journal of immunology (Baltimore, Md. : 1950)》2001,167(4):1954-1961
Mice deficient for fibroblast growth factor (Fgf)R2-IIIb show a block in thymic growth after embryonic day 12.5, a stage that just precedes its detection in thymic epithelial cells. Fgf7 and Fgf10, the main ligands for FgfR2-IIIb, are expressed in the mesenchyme surrounding the thymic epithelial primordium, and Fgf10-deficient mice also exhibit impaired thymic growth. Hence, Fgf signaling is essential for thymic epithelial proliferation. In addition to the proliferative block, most thymic epithelial cells fail to progress from an immature cytokeratin 5-positive to a cytokeratin 5-negative phenotype. Nevertheless, sufficient epithelial cell differentiation occurs in the severely hypoplastic thymus to allow the development of CD4/CD8-double-positive thymocytes and a very small number of single-positive thymocytes expressing TCRs. 相似文献
5.
6.
Culture and characterization of thymic epithelium from autoimmune NZB and NZB/W mice 总被引:2,自引:0,他引:2
Autoimmune NZB and NZB/W mice display early abnormalities in thymus histology, T cell development, and mature T cell function. Abnormalities in the subcapsular/medullary thymic epithelium (TE) can also be inferred from the early disappearance of thymulin from NZB. It has also been reported that NZB thymic epithelial cells do not grow in culture conditions that support the growth of these cells from other strains of mice. In order to study the contribution of TE to the abnormal T cell development and function in NZB and NZB/W mice, we have devised a culture system which supports the growth of TE cells from these mice. The method involves the use of culture vessels coated with extracellular matrix produced by a rat thymic epithelial cell line. TEA3A1, and selective low-calcium, low-serum medium. In addition TEA3A1 cells have been used as an antigen to generate monoclonal antibodies specific for subcapsular/medullary TE. These antibodies, as well as others already available, have been used to show that the culture conditions described here select for cells displaying subcapsular/medullary TE markers, whereas markers for cortical TE and macrophages are absent. 相似文献
7.
Colonization of rat thymic anlage by the first wave of hemopoietic precursor cells (HPc) was investigated by means of transmission
electron microscopy and immunocytochemistry. HPc began migration into the thymic anlage between 13 and 13.5 gestation days
(GD), terminated colonization at about GD 16, and migrated sequentially through the two compartments of the thymic anlage
under the control of typical populations of stromal cells. First, HPc migrated through the external compartment of the perithymic
mesenchyme, tightly interconnected with fibroblasts. The type of junctions between the cells indicated that the fibroblasts
played a role in the control of HPc trafficking and in their entrance to the epithelial compartment. The second stage of colonization
was initiated by the entrance of HPc to the epithelial compartment and their interaction with thymic epithelial cells (TECs).
Based on morphological criteria, two populations of HPc were distinguished that colonized the anlage at various stages of
its development. The predominant population with ultrastructural traits common to thymocytes “homed” into the epithelial type
primordium. A small number of HPc, identified by protein S-100 expression and by Birbeck’s granules as precursors of dendritic
cells, colonized lymphoepithelial anlage in which subsets of cortical and medullary TECs could be distinguished. Thymocyte
migration and their reciprocal interactions with cortical TECs differed from the trafficking of dendritic cells toward the
medulla. The results demonstrated the influence of maturing thymocytes on the development of cortical epithelial cells and
the dynamic organization of the medullary microenvironment with direct involvement of dendritic cells.
This study was supported by UMS grant 501-2-0003404. 相似文献
8.
Measles Virus Infection Induces Terminal Differentiation of Human Thymic Epithelial Cells 总被引:3,自引:3,他引:0 下载免费PDF全文
Hlne Valentin Olga Azocar Branka Horvat Rejane Williems Robert Garrone Alexei Evlashev Maria L. Toribio Chantal Rabourdin-Combe 《Journal of virology》1999,73(3):2212-2221
Measles virus infection induces a profound immunosuppression that may lead to serious secondary infections and mortality. In this report, we show that the human cortical thymic epithelial cell line is highly susceptible to measles virus infection in vitro, resulting in infectious viral particle production and syncytium formation. Measles virus inhibits thymic epithelial cell growth and induces an arrest in the G0/G1 phases of the cell cycle. Moreover, we show that measles virus induces a progressive thymic epithelial cell differentiation process: attached measles virus-infected epithelial cells correspond to an intermediate state of differentiation while floating cells, recovered from cell culture supernatants, are fully differentiated. Measles virus-induced thymic epithelial cell differentiation is characterized by morphological and phenotypic changes. Measles virus-infected attached cells present fusiform and stellate shapes followed by a loss of cell-cell contacts and a shift from low- to high-molecular-weight keratin expression. Measles virus infection induces thymic epithelial cell apoptosis in terminally differentiated cells, revealed by the condensation and degradation of DNA in measles virus-infected floating thymic epithelial cells. Because thymic epithelial cells are required for the generation of immunocompetent T lymphocytes, our results suggest that measles virus-induced terminal differentiation of thymic epithelial cells may contribute to immunosuppression, particularly in children, in whom the thymic microenvironment is of critical importance for the development and maturation of a functional immune system. 相似文献
9.
The regulation of thymic epithelial cell function has been examined using pure cultures of morphologically distinct thymic epithelial cells and the ubiquitous hormone epidermal growth factor (EGF). Small thymic epithelial cells, TECS, had receptors for EGF with high affinity, Kd = 1.2 X 10(-9) M, and exhibited increased DNA synthesis and increased RNA synthesis upon stimulation with EGF. In addition, incubation of TECS monolayers with EGF resulted in enhanced production of prostaglandin E2. In contrast, large thymic epithelial cells, TECL, did not express receptors for EGF and demonstrated no biological response to the hormone. These results suggest the possibility that intrathymic regulation of lymphoid cells may occur via the action of "nonimmunologic" mediators on thymic epithelial cells. They further suggest the more general possibility that immunologic and nonimmunologic hormonal systems may be linked via intersecting cellular pathways. 相似文献
10.
Jerry Y. Niederkorn Dale R. Meyer John E. Ubelaker James H. Martin 《In vitro cellular & developmental biology. Plant》1990,26(9):923-930
Summary A widely utilized rabbit corneal cell line, SIRC, was characterized ultrastructurally and immunohistologically. Although SIRC
cells are often described as being of epithelial origin, important ultrastructural and antigenic characteristics indicate
that these cells are fibroblastic and not epithelial. SIRC cells lack desmosomes, cytoplasmic filaments, and cytokeratin—structures
that are characteristic of corneal epithelial cells. By contrast, the dendritic morphology, presence of vimentin, and the
extensive dense accumulations of ribosomes and rough endoplasmic reticulum are consistent with a fibroblastic phenotype. Collectively,
the morphology, ultrastructural features, and antigenic composition favor the hypothesis that SIRC cells are fibroblastic
cells (keratocytes) and not corneal epithelial cells.
This work supported in part by grant EY 07641 from the National Institutes of Health, Bethesda, MD, and an unrestricted grant
from Research to Prevent Blindness, Inc., New York. 相似文献
11.
12.
Epidermal growth factor promotes a neural phenotype in thymic epithelial cells and enhances neuropoietic cytokine expression 总被引:1,自引:0,他引:1 下载免费PDF全文
《The Journal of cell biology》1995,130(1):183-192
Neural crest-derived cells populate the thymus, and their coexistence with epithelial cells is required for proper organ development and T cell education function. We show here that epidermal growth factor (EGF), a major epithelial cell growth-enhancing agent, has a morphogenetic action to promote the expression of a neuronal phenotype (e.g., neurofilament expression) in cultured thymic epithelial cells that are characterized by a cytokeratin-positive epithelial cell background. The proliferation of such neurodifferentiated cells is also enhanced by EGF. Furthermore, the growth factor enhances cells that express the genes encoding the preprotachykinin A-generated neuropeptides and bipotential neuropoietic and lymphopoietic cytokines ciliary neurotrophic factor and interleukin-6. These cytokines also enhance the neuronal phenotype of thymic epithelial cells. Therefore, EGF appears to be a composite autocrine/paracrine neuromodulator in thymic stroma. This suggests that EGF may regulate thymus-dependent immune functions by promoting neuronal gene expression in neural crest- derived cells. 相似文献
13.
William J. Lindblad Louise C. Flood 《In vitro cellular & developmental biology. Plant》1987,23(6):413-416
Summary Several dermal fibroblast lines have been established from explants taken from adult rats. The cells have been cultured for
2 yr and possess stable and well-defined growth characteristics through subculture 18. The cells are readily stored in liquid
nitrogen with good viability after thawing.
Collagenase activity secreted into the culture medium of the cells at different periods of growth has been examined. There
is an 88% drop in total enzyme activity present in the medium between 4 and 14 d of culture, when the cells were plated to
reach confluence at Day 8 to 10. A more pronounced fall is noted at earlier times when the cells are plated at a higher density.
The correlation between DNA content of the cell monolayer and enzyme activity was −0.895, indicating a possible relationship
between the growth of cells and collagenase release.
This study was supported in part by grant AM 30856 from the National Institutes of Health, Bethesda, MD. 相似文献
14.
A method for the rapid establishment of normal adult mammalian colonic epithelial cell cultures 总被引:6,自引:0,他引:6
Alda Vidrich Rajeswari Ravindranath Kianbanoo Farsi Stephan Targan 《In vitro cellular & developmental biology. Plant》1988,24(3):188-194
Summary Normal colonic epithelial cell cultures of mammalian origin are required to facilitate the study of both normal cellular functions
as well as pathogenesis of certain (human) colonic diseases. To date, little information is available regarding the growth
requirements of colonic epithelial cells in culture of eitehr animal or human origin. Such data would enable the development
of a long-term culture system for these cells. In this study, we present methodology that results in the establishment of
homogeneous cultures of adult rabbit colonic epithelial reproducibly, quickly, and in quantity. The epithelial nature of the
cultures is unambiguously established by intermediate filament typing using antikeratin antibodies. Such culutres can now
be used for a variety of functional studies as well as to investigate the growth requirements of colonic epithelial in culture.
This work was supported by the Blinder Foundation for Crohn’s Disease Research, Harbor UCLA IBD Center (AM 36200) and grant
AM 27806 from the National Institutes of Health, Bethesda, MD. 相似文献
15.
Prof. Dr. W. Leene R. de Waal Malefijt P. J. M. Roholl K. A. Hoeben 《Cell and tissue research》1988,253(1):61-68
Summary In situ pre-existing complexes of epithelial cells and thymocytes having thymic nurse cell characteristics were visualized in the murine thymus cortex using dexamethasone as a potent killer of cortisone-sensitive thymocytes. The degradation and subsequent depletion of cortisone-sensitive thymocytes enclosed within cortical epithelial cells appeared to be paralleled by thymocyte degradation and depletion in thymic nurse cells isolated from thymic tissue fragments from dexamethasone-treated animals. This suggests that thymic nurse cells are derived from pre-existing sealed complexes of cortical epithelial cells and thymocytes. Not all thymocytes situated within in situ epithelial or thymic nurse cells complexes appear to be cortisone-sensitive: a minority of 1–2 thymocytes per complex survives the dexamethasone-treatment, thus constituting a minor subset of cortical cortisone-resistant thymocytes predominantly localized within cortical epithelial cells in situ and within thymic nurse cells derived from such structures. Cortisone resistance in thymocytes thus seems to be acquired within the cortical epithelial cell microenvironment. Cortisone-resistant thymocytes in thymic nurse cells express the phenotype of mature precursors of the T helper lineage, indicating that the in situ correlates of thymic nurse cells may play an important role in T cell maturation and selection. 相似文献
16.
Summary Thymulin, a thymic hormone, is a nonapeptide requiring zinc for biological activity. It has been shown that epithelial cells, forming part of the thymic reticulum, secrete this hormone and/or store it within cytoplasmic vacuoles. X-ray electron-probe microanalysis (EPMA) has been used to detect zinc in the thymus. Low concentrations of zinc have been demonstrated in the dense granules contained in clear vacuoles of some epithelial cells in normal and ZnCl2-injected mouse thymuses, thus suggesting that the metal may be coupled to the peptide before the secretion of the hormone from the cells. 相似文献
17.
V. A. Varma Susan A. Melin Thomas A. Adamec B. Hugh Dorman Jill M. Siegfried Leslie A. Walton Charles N. Carney Carol R. Norton David G. Kaufman 《In vitro cellular & developmental biology. Plant》1982,18(11):911-918
Summary Monolayer cultures can be established from human endometrial tissue after enzymatic dispersal into isolated glands or single
cells. Three cell types that have distinct morphology by light and electron microscopy are observed in the resulting primary
cultures. One cell type, an elongated spindle cell, is similar in appearance to fibroblasts derived from other tissues. A
second cell type forms colonies of tightly cohesive cells, ranging in shape from oval to polygonal. These cells have typical
organelles and junctional complexes characteristic of epithelial cells from the endometrium. The third cell type assumes a
pavement-like appearance composed of polygonal cells when viewed by phase contrast microscopy, but lacks distinctive ultrastructural
features of epithelial cells. These cells in culture resemble the endometrial stromal cell, the predominant cell type of the
human endometrium in vivo. The epithelial cell does not survive subculturing but the other two cell types can be passaged
through several generations and can be stored in liquid nitrogen and subsequently returned to culture.
This work was supported by contract N01-CP75956 and grant R01-CA31733 from the National Cancer Institute. V. A. Varma is a
recipient of an American Cancer Society fellowship; B. H. Dorman, a predoctoral fellowship from the Chemical Industry Institute
of Toxicology; J. M. Siegfried, a training grant (CA09156) from the National Cancer Institute; and D. G. Kaufman, a Research
Career Development Award (K04-CA-00431) from the National Cancer Institute. 相似文献
18.
A new diploid nontumorigenic human breast epithelial cell line isolated and propagated in chemically defined medium 总被引:10,自引:0,他引:10
P. Briand O. W. Petersen B. Van Deurs 《In vitro cellular & developmental biology. Plant》1987,23(3):181-188
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. 相似文献
19.
Development of functional thymic epithelial cells occurs independently of lymphostromal interactions
The thymus provides a specialised microenvironment for the development of T-cell precursors. This developmental programme depends upon interactions with stromal cells such as thymic epithelial cells, which provide signals for proliferation, survival and differentiation. In turn, it has been proposed that development of thymic epithelial cells themselves is regulated by signals produced by developing thymocytes. Evidence in support of this symbiotic relationship, termed thymic crosstalk, comes from studies analysing the thymus of adult mice harbouring blocks at specific stages of thymocyte development, where it is difficult to separate mechanisms regulating the initial development of thymic epithelial cells from those regulating their maintenance. To distinguish between these processes, we have analysed the initial developmental programme of thymic epithelial cells within the embryonic thymus, in either the presence or absence of normal T-cell development. We show that keratin 5+8+ precursor epithelial cells present in the early thymic rudiment differentiate into discrete cortical and medullary epithelial subsets displaying normal gene expression profiles, and acquire functional competence, independently of signals from T-cell precursors. Thus, our findings redefine current models of thymus development and argue against a role for thymocyte-epithelial cell crosstalk in the development of thymic epithelial progenitors. 相似文献
20.
William B. Milisen Glen K. Miller Stephen A. Benjamin Gary J. Sibert 《In vitro cellular & developmental biology. Plant》1988,24(10):972-980
Summary An explant culture procedure has been developed that makes it possible to measure the relative growth capacity of the epithelial
and mesenchymal cells of the canine thymus gland. Standardized growth conditions were obtained by size-grading thymic fragments
and counting to allow uniform fragment density during culture. After 6 d in culture, outgrowth from the fragments formed colonies
that could be classified into epithelial, mixed, or spindle cell type. Uniform fragment size and number in each flask allowed
calculation of the total plating efficiency, relative distribution of colony types, and mean colony diameters for thymic fragments
collected from fetuses (50 d of gestation), neonates (0 d postpartum), and juveniles (70 d postpartum). Data show age-related
changes in the proliferative capacity of the cells in all three colony types. The most significant difference was seen in
the epithelium, which showed a 30% reduction in mean colony diameter over the 2 wk between fetal and neonatal ages and a 23%
reduction over the postnatal period of 70 d. Significant reductions were seen in the other colony types as well. Because the
severity of the effect of many injurious agents is proportional to the rate of growth of the target cells, these data suggest
that the thymus gland of the fetus may be more sensitive to physical or chemical injury than is the neonate or adult.
Funding was provided by grants NCI CA36456, NCI T15CA09408, NIEHS ES07152 from the National Institutes of Health, Bethesda,
MD, and by USDA Animal Health and Disease Program (PL 95-113). 相似文献