Thymus-derived stromal cell lines

We derived stromal cell lines from mouse thymus using methods previously established for bone marrow stroma. Two main morphologically distinct groups of cell strains emerged: epithelioid and mixed fibroblast-macrophage. Transmission electron microscopy revealed frequent junctional-complex formations between adjacent cells, a feature that characterized almost all of the thymus stromal lines, but was confined to only one of the five distinct subtypes of cell lines from bone marrow. In contrast to marrow stromal cells, the thymus-derived cell lines were all negative with fat-detecting reagents, had low acid phosphatase and no basic phosphatase activities and were unable to support the in vitro proliferation of myeloid progenitor cells (CFU-gm). Leukemia cell inhibitory activity (LCIA) was detected in one of the thymus stromal cell lines. The differences observed between cell lines derived from the stroma of the thymus and those from bone marrow may relate to the functional specificities of these organs.     

Fish cell lines: establishment and characterization of nine cell lines from salmonids

Nine permanent cell lines have been established from five species of salmonids native to America's Pacific Northwest. With the exception of a hepatoma from an adult trout, the lines were derived from normal tissues of embryonic or juvenile fish. Cells were routinely grown in Eagle's minimum essential medium with 10% fetal bovine serum. Optimum growth temperatures for these lines ranged from 21 to 24 degrees C. All survived storage for at least 1 yr at -65 degrees C and at least 5 yr in liquid nitrogen. Six of the lines were demonstrably free of any microbial contamination but mycoplasmas were found in three. Eight of the lines were heteroploid. The morphology of only one was fibroblastic. All the lines effectively replicated one or more of the common salmonid viruses. Isozyme patterns were consistent with those of the species of origin. These cell lines have significant application in fish virology.     

Fish cell lines: Establishment and characterization of nine cell lines from salmonids

Summary Nine permanent cell lines have been established from five species of salmonids native to America's Pacific Northwest. With the exception of a hepatoma from an adult trout, the lines were derived from normal tissues of embryonic or juvenile fish. Cells were routinely grown in Eagle's minimum essential medium with 10% fetal bovine serum. Optimum growth temperatures for these lines ranged from 21 to 24°C. All survived storage for at least 1 yr at −65°C and at least 5 yr in liquid nitrogen. Six of the lines were demonstrably free of any microbial contamination but mycoplasmas were found in three. Eight of the lines were heteroploid. The morphology of only one was fibroblastic. All the lines effectively replicated one or more of the common salmonid viruses. Isozyme patterns were consistent with those of the species of origin. These cell lines have significant application in fish virology. This work is a result of research sponsored in part by the Oregon State University Sea Grant College Program supported by NOAA Office of Sea Grant, U.S. Department of Commerce, under Grant NA79AA-D-0016 and by the Oregon Department of Fish and Wildlife under PL-89304 Anadromous Fish Act and is Oregon Agricultural Experiment Station Technical Paper 6857.     

Human B-lymphoid cell lines.

The collective efforts during almost three decades by hematologists, tumor biologists and immunologists have provided a collection of established human hematopoietic cell lines, representing most of the hematopoietic cell lineages. The representativity of cell lines derived from the B cell differentiation lineage, however, is the most impressive. Human B-lymphoid cell lines are extensively used world wide as models in studies of various aspects of B cell biology and as tools in research on the etiology, pathogenesis and the biology of leukemia and lymphoma. Lymphoblastoid cell lines (LCL) carrying the Epstein-Barr Virus (EBV) are of particular importance. These lines can be established spontaneously from blood and lymphoid tissue from any EBV positive individual by special techniques, and from all individuals by EBV infection of peripheral blood B cells by EBV infection in vitro. At spontaneous establishment B cells, latently infected by EBV in vivo, will release EBV which subsequently infects normal EBV-negative B cells and immortalizes them into LCL cells, but direct outgrowth of the latently infected B cells as LCLs has also been documented. The target B cells for the EBV infection in vitro are not fully defined-most are mature B cells but also pro-B and pre-B and some B-blasts can be infected. Apart from their capacity for infinite growth, LCL cells have non-malignant properties, e. g. they are diploid, do not grow in agarose and do not form tumors upon inoculation subcutaneously in nude mice. LCLs have a phenotype corresponding to activated B cells (B-blasts) and have been used as "the E. Coli" of eukaryotic cells for about two decades. LCLs are derived at a high frequency also from tumor biopsies of EBV positive patients with leukemia and lymphoma. However, tumor cell lines are available from most of the B cell lineage-derived leukemias, B-lymphomas and myeloma. The frequency of successful establishment has been particularly high from EBV positive Burkitt's lymphoma (BL). From EBV genome negative BL and other B-lymphoma and B-leukemia biopsies the frequency of successful, spontaneous establishment is low (5-10%), and such lines have, with rare exceptions, been derived from pleural effusions and ascitis of patients with advanced, chemotherapy resistant, disease. Many of the cell lines therefore do not represent the clinically most common types of leukemia and lymphoma. No authentic malignant cell lines have been established from chronic lymphocytic leukemia (CLL), prolymphocytic leukemia (PLL) and Waldenstr?m's disease.(ABSTRACT TRUNCATED AT 400 WORDS)     

Characterization of invertebrate cell lines

Summary The usefulness of four serologic techniques for distinguishing five selected lepidopteran cell lines was evaluated; the techniques included complement fixation, hemagglutination. immunodiffusion, and immunoelectrophoresis. The five selected lepidopteran cell lines represent three taxonomic families of Lepidoptera with one family, Noctuidae, containing two cell lines derived from insects within the same genus. The five cell lines were crossreactive in complement-fixation tests, but the lines were distinguishable at a familic level when two units of antigens were used in the test. Agglutination of goose erythrocytes was not observed with the antigens over a pH range of 5.8 to 7.2 at 4°C or ambient temperature. Immunodiffusion tests demonstrated a common cross-reactive antigen(s), but spurs of partial identity and the presence of extra precipitin bands were indicative that differentiation at a familic level was possible. Immunoelectrophoresis of the cellular antigens also revealed common cross-reactive precipitin arcs, but the number and clarity of arcs in homologous systems was increased such that four of the five cell lines were distinguishable. A basic protein was consistently seen in the homologous system, but it was absent in the heterologous systems. Although these data suggest that immunoelectrophoresis was the best serologic technique for distinguishing the five lepidopteran cell lines, the shortcomings of this approach are also discussed. This research was supported in part by the World Health Organization, The Rockefeller Foundation, and U.S. Public Health Service Grant AI-13727.     

Characterization of invertebrate cell lines

Summary Cell extracts of five mosquito cell lines and a tick cell line were examined for four cellular isozymes using a cellulose-acetate electrophoretic technique. This method distinguished the cell lines that were derived from the different species. Intraspecies distinctions were not made using the cell lines tested; the significance of this finding is discussed. The usefulness of this technique in identifying a potentially mislabeled cell line was demonstrated. This research was supported by contracts, DADA 17-72C-2170 of the U.S. Army and N00014-78C-0104 of the U.S. Office of Naval Research and grants from the World Health Organization and the Rockefeller Foundation.     

Established cell lines ofDrosophila hydei

Summary Four cell lines have been isolated fromDrosophila hydei embryos. Three lines have a normal XY karyotype, the fourth has an XO karyotype with an additional small heterochromatic fragment. The cells contain presumable cytoplasmic virus like particles. This work was supported by a travel grant to Dr. N. H. Lubsen from the Netherlands Organization for the Advancement of Pure Research (Z. W. O.).     

Characterization of invertebrate cell lines

Summary A reliable, simple method for the separation of four cellular isozymes utilizing celluloseacetate electrophoresis is described. Cell extracts of 16 cell lines were examined previously, utilizing starch gel electrophoretic techniques. These same cell extracts were retested for their isozyme phenotype using the cellulose-acetate electrophoretic system. These data indicate that the results of the two electrophoretic systems are comparable. Isozyme analyses of freshly prepared cell extracts of theAedes albopictus (ATC-15) andSpodoptera frugiperda (IPLB-SF-21AE) cell lines resulted in identical isozyme mobilities when compared with their respective stored counterparts. Since the cellulose-acetate electrophoretic system was able to separate cellular isozymes into characteristic patterns, distinctions between cell lines were made. The application of this technique for identification and characterization of invertebrate cell lines is discussed. This research was supported in part by the Rockefeller Foundation and U.S. Public Health Service Grant AI-13727.     

Comparing N-glycan processing in mammalian cell lines to native and engineered lepidopteran insect cell lines

In the past decades, a large number of studies in mammalian cells have revealed that processing of glycoproteins is compartmentalized into several subcellular organelles that process N-glycans to generate complex-type oligosaccharides with terminal N -acetlyneuraminic acid. Recent studies also suggested that processing of N-glycans in insect cells appear to follow a similar initial pathway but diverge at subsequent processing steps. N-glycans from insect cell lines are not usually processed to terminally sialylated complex-type structures but are instead modified to paucimannosidic or oligomannose structures. These differences in processing between insect cells and mammalian cells are due to insufficient expression of multiple processing enzymes including glycosyltransferases responsible for generating complex-type structures and metabolic enzymes involved in generating appropriate sugar nucleotides. Recent genomics studies suggest that insects themselves may include many of these complex transferases and metabolic enzymes at certain developmental stages but expression is lost or limited in most lines derived for cell culture. In addition, insect cells include an N -acetylglucosaminidase that removes a terminal N -acetylglucosamine from the N-glycan. The innermost N -acetylglucosamine residue attached to asparagine residue is also modified with alpha(1,3)-linked fucose, a potential allergenic epitope, in some insect cells. In spite of these limitations in N-glycosylation, insect cells have been widely used to express various recombinant proteins with the baculovirus expression vector system, taking advantage of their safety, ease of use, and high productivity. Recently, genetic engineering techniques have been applied successfully to insect cells in order to enable them to produce glycoproteins which include complex-type N-glycans. Modifications to insect N-glycan processing include the expression of missing glycosyltransferases and inclusion of the metabolic enzymes responsible for generating the essential donor sugar nucleotide, CMP- N -acetylneuraminic acid, required for sialylation. Inhibition of N -acetylglucosaminidase has also been applied to alter N-glycan processing in insect cells. This review summarizes current knowledge on N-glycan processing in lepidopteran insect cell lines, and recent progress in glycoengineering lepidopteran insect cells to produce glycoproteins containing complex N-glycans.     

Alpha-lipoic acid induces p27Kip-dependent cell cycle arrest in non-transformed cell lines and apoptosis in tumor cell lines

alpha-Lipoic acid is a naturally-occurring co-factor found in a number of multi-enzyme complexes regulating metabolism. We report here that alpha-lipoic acid induces hyperacetylation of histones in vivo and has differential effects on the growth and viability of normal versus transformed cell lines. The human tumor cell lines FaDu and Jurkat, as well as a Ki-v-Ras-transformed Balb/c-3T3 murine mesenchymal cell line, all initiated apoptosis following exposure to alpha-lipoic acid. In contrast, treatment of non-transformed cell lines with alpha-lipoic acid resulted only in reversible cell cycle arrest in G0/G1. Treatment with butyrate, another short-chain fatty acid, induced a G0/G1 arrest in both transformed and non-transformed cell lines. alpha-Lipoic acid caused a post-translational elevation in the levels of the cyclin-dependent kinase inhibitor p27Kip1. Studies using p27Kip1-deficient MEF cells demonstrated that p27Kip1 was required for the alpha-lipoic acid-mediated cell cycle arrest. The mechanism of apoptosis was independent of Fas-mediated signaling, as alpha-lipoic acid-treated Jurkat cell mutants deficient in Fas or FADD retained sensitivity to apoptosis. The differential selectivity of the pro-apoptotic effects of alpha-lipoic acid for transformed cells supports its potential use in the treatment of neoplastic disorders.     

芫菁斑蝥素对喉癌细胞和胃癌细胞的抑制作用

【目的】 研究提取自眼斑芫菁Mylabris cichorii (Linnaeus)体内的斑蝥素对人喉癌HEP-2细胞和人胃癌BGC-823细胞的抑制、以及对细胞周期分布的影响。【方法】 将斑蝥素作用于经体外培养的人喉癌HEP-2细胞和人胃癌BGC-823细胞, 采用MTT法进行体外细胞抑制实验, 测定斑蝥素对这2种癌细胞生长的抑制率与剂量效应;采用流式细胞术测定斑蝥素处理的人喉癌HEP-2细胞的细胞周期;并通过光学显微镜观察其细胞形态学改变。【结果】 斑蝥素浓度为1.28 μmol/L时, 对HEP-2细胞有显著抑制作用, 且随药物浓度升高其抑制作用增强, 呈剂量效应关系, 抑制中浓度为2.88 μmol/L;斑蝥素浓度为20.4 μmol/L时, 对BGC-823细胞有显著抑制作用, 且随药物浓度升高其抑制作用增强, 呈剂量效应关系, 抑制中浓度为54.85 μmol/L。用浓度1.44和2.88 μmol/L的斑蝥素处理HEP-2细胞24 h后, G2-M期分布从8.21%增加到22.29%, S期细胞分布从14.33%增加到21.61%, 且随药物浓度升高其阻滞作用增加, 呈剂量效应关系。G0-G1期细胞分布都有所降低, 从77.45%降低到56.10%, G0-G1期峰前无显著的亚二倍体峰出现, 说明斑蝥素未能够诱导HEP-2细胞发生凋亡。光镜检查显示：HEP-2细胞可出现细胞收缩、胞膜突出、核碎裂等现象。【结论】 斑蝥素对治疗喉癌的效果可能较为理想, 而对胃癌的作用则不明显。