Phenotypic characterization of KU812, a cell line identified as an immature human basophilic leukocyte

The knowledge about the differentiation of basophilic leukocytes is fragmentary. This report discusses a detailed phenotypic characterization of molecular markers for hematopoietic differentiation in a basophilic leukemia cell line, KU812. The expression of markers for lymphoid, erythroid, neutrophil, eosinophil, monocytic, megakaryocytic, mast cell and basophil differentiation was analyzed at the mRNA level by Northern blots in the KU812 cells, and for reference, in a panel of human cell lines representative of the different hematopoietic differentiation lineages. KU812 was found to express a number of mast cell and basophil-related proteins, i.e. mast cell tryptase, mast cell carboxypeptidase A, high-affinity immunoglobulin (IgE) receptor α and γ chains and the core protein for heparin and chondroitin sulphate synthesis. We found no expression of a number of monocyte/-macrophage or neutrophil leukocyte markers except for lysozyme. From earlier studies, it has been shown that lysozyme is not expressed in murine mucosal mast cell lines. This finding, together with the expression of the mast cell carboxypeptidase in KU812 might distunguish the phenotype of this cell line from that typical of mucosal mast cell lines in rodents. We found a low level of expression of the eosinophil and basophil marker, major basic protein, which might indicate a relationship between basophils and eosinophils. No expression is, however, detected with the eosinophil-specific markers eosinophil cationic protein, eosinophil-derived neurotoxin or eosinophil peroxidase. We also report an extensive screening for inducers of basophilic differentiation of the KU812 cells. The most efficient protocol of induction included serum starvation which led to a dramatic increase in a number of markers specific for mast cells and basophils such as tryptase, carboxypeptidase A and the heparin core protein. Finally, diisopropylfluorophosphate analysis of total protein extracts from KU812 show four labeled protein bands with sodium dodecyl sulfate-polyacryl-amide gel electrophoresis, indicating that this cell line expresses at least three previously undescribed serine proteases of which one or more could be a potential basophil-specific marker(s).     

Fabrication and characterization of porous alginate/polyvinyl alcohol hybrid scaffolds for 3D cell culture

Porous alginate/polyvinyl alcohol (PVA) hybrid scaffolds as bioartificial cell scaffolds were fabricated to improve cell compatibility as well as flexibility of the scaffolds. The alginate/PVA hybrid scaffolds with different PVA compositions up to 50 wt% were fabricated by a modified freeze-drying method including the physical cross-linking of PVA and the following chemical cross-linking of alginate. The prepared alginate/PVA hybrid scaffolds were characterized by morphology observations using scanning electron microscopy (SEM), the measurements of porosity and average pore sizes and the measurements of compressive strength and modulus. The scaffolds exhibited highly porous, open-cellular pore structures with almost the same surface and cross-sectional porosities (total porosities about 85%, regardless of PVA composition) and the pore sizes from about 290 microm to about 190 microm with increasing PVA composition. The alginate/PVA hybrid scaffolds were more soft and elastic than the control alginate scaffold without significant changes of mechanical strength. The scaffolds were examined for their in vitro cell compatibility by the culture of chondrocytes (human chondrocyte cell line) in the scaffolds and the following analyses by MTT assay and SEM observation. It was observed that the alginate/PVA scaffolds had better cell adhesion and faster growth than the control alginate scaffold. It seems that 30 wt% addition of PVA to alginate in the fabrication of the hybrid scaffolds is desirable for improving their flexibility and cell compatibility.     

Establishment and characterization of a serous papillary adenocarcinoma cell line of the human ovary in a serum-free culture.

In order to clarify the biologic characteristics of serous papillary adenocarcinoma of the human ovary, we tried to establish a continuous cell line using four primary tumor specimens derived from four patients with such tumors. We also evaluated c-myc, MYCN and c-erbB2 gene amplification in the cultured cells, and the xenografts, as well as in these four primary tissue specimens by a Southern blot analysis. One continuous cell line, named as FU-OV-1, was established in a serum-free culture system and this line propagated continuously for 96 serial passages over a 2-year-period in vitro. FU-OV-1 reproduced and still maintained the characteristics of the original tumor. C-myc gene amplification was found in the FU-OV-1 cells, and the xenografts, as well as in only the primary tumor of FU-OV-1 out of the four primary serous papillary adenocarcinomas. However, neither MYCN amplification nor c-erbB2 amplification was observed in any tumor specimens including FU-OV-1 cells. In conclusion, FU-OV-1 is thus considered to be a useful system for studying the biological behavior of serous papillary adenocarcinoma in the human ovary. The results of this study suggest that c-myc gene amplification might thus be associated with the progression of this tumor both in vitro and in vivo.     

Establishment and characterization of a new xenograft-derived human esophageal squamous cell carcinoma cell line HKESC-4 of Chinese origin

A new human esophageal cancer cell line, HKESC-4, was established from a nude-mouse xenograft of a moderately differentiated esophageal squamous cell carcinoma (ESCC) developed from a 65-year-old Hong Kong Chinese man. The cellular characteristics (morphological, electron microscopic, and immunohistochemical studies), tumorigenicity in athymic nude mice, cytogenetic features, and DNA ploidy of the cell line were investigated. The cell line was maintained in vitro for 17 months and passaged 80 times. HKESC-4 grew as a monolayer, with a doubling time of 63 hours. The epithelial nature of HKESC-4 included the presence of cytokeratin intermediate filaments, as shown by antibodies (AE1/AF3, CAM5.2, and MAK 6), and the presence of the tonofilaments, as seen under electron microscopy. HKESC-4 was tumorigenic in nude mice and had DNA aneuploidy. The cytogenetic abnormalities of HKESC-4 included -1, -2, -3, -4, -5, -6, -7, -8, -9, -10, -11, -12, -15, -16, -17, -18, -19, +20, -21, -22, +del(11)(p11), +i(11)(q10), and +21 marker chromosomes. Comparative genomic hybridization analysis demonstrated chromosomal gains at 1p36.13, 3q23 approximately q28, 5p15.33 approximately p15.1, 6p25.1 approximately p22.3, 7p21.3 approximately p11.2, 7q11.21 approximately q21.13, 8q23.3 approximately q23.3, 11p11.2, 11q12.1 approximately q13.2, 14q21.3 approximately q32.2, 17p13.3, 18p11.32 approximately p11.31, and 20p13 approximately p12.2 and chromosomal losses at 1q12, 2p25.1 approximately p24.3, 13p13 approximately p11.2, 21p, 22p13 approximately p11.2, and Y. The newly established cell line HKESC-4 promises to be a useful tool in future studies of molecular pathogenesis and therapeutics in ESCC.     

Karyotypic characterization of a new human embryonal rhabdomyosarcoma cell line

Chromosomal analysis of an advanced recurrent rhabdomyosarcoma of the embryonal type was performed on cell cultures in the 9th passage of in vitro cultivation. This tumor showed a modal karyotype of 54 and was characterized by multiple numerical and structural chromosome abnormalities, all present in high frequencies. Abnormalities observed in 100% of the cells included a der(1) chromosome with a short unidentified insertion between q31 and q32; a der(1) chromosome, arising from insertion at the same breakpoint of a longer segment with a duplicated 1q31 band and translocation of 13q23----qter to 1p36, a deleted tetrasomic 13q23----qter, and a der(4) chromosome showing 1p36----pter translocated to 4p13. Other common abnormalities included trisomy of chromosomes 8, 13, and 9p, deletions of chromosomes 6, 10, 11, and 12, and presence of marker chromosomes. Characterization of the established line at the 38th passage evidenced the persistence of both the modal karyotype and all the numerical and structural abnormalities previously found. The results of this study provide further evidence of the major involvement of alterations in chromosome 1 in the progression of rhabdomyosarcoma.     

Establishment and characterization of a new highly metastatic human osteosarcoma cell line

Osteosarcoma is the most common primary malignancy of bone in children and young adults. There is a paucity of tumorigenic and highly metastatic human osteosarcoma cell lines that have not been further transformed by exogenous means. Here we establish and characterize a highly metastatic human osteosarcoma cell line that is derived from a poorly metastatic MG63 line through serial passage in nude mice via intratibial injections. The occasional pulmonary metastases developed from MG63 were harvested and repassaged in mice until a highly metastatic subline (MG63.2) was established. The parental MG63 and highly metastatic MG63.2 cells were further characterized in vitro and in vivo. MG63.2 cells demonstrated increased cell migration and invasion compared to the parental MG63 cells. Conversely, cell adhesion was significantly greater in MG63 cells when compared to the MG63.2 cells. MG63.2 cells grew at a slightly slower rate than that of the parental cells. When injected into nude mice, MG63.2 cells had a greater than 200-fold increase in developing pulmonary metastases compared to the parental MG63 cells. MG63.2 cells also formed larger primary tumors when compared to the parental MG63 cells. Further analysis revealed that ezrin expression was up-regulated in the metastatic MG63.2 cells. Interestingly, expressions of MMP-2 and MMP-9 were down-regulated, and expression of TIMP-2 was up-regulated in the MG63.2 cells. Taken together, we have established and characterized a highly metastatic human osteosarcoma cell line that should serve as a valuable tool for future investigations on the pathogenesis, metastasis, and potential treatments of human osteosarcoma.     

Establishment and characterization of a human gastric carcinoma cell line TMC-1

Established cancer cell lines are useful in the study of various cancers. We established a human gastric carcinoma cell line TMC-1 derived from the lymph node of a moderately differentiated adenocarcinoma of the stomach. TMC-1 cells grew in vitro as a mixture of attached and suspension cells, and exhibited spindle or ovoid morphology. They had a population doubling time of 15 h, a plating efficiency of 61%, formed colonies in semisolid agar, secreted the tumor marker CA 19-9, and were tumorigenic in athymic nude mice. The cells expressed E-cadherin and beta-catenin. The karyotypic analysis demonstrated hyperdiploid features with a modal chromosome of 53. The cell had the deletion at chromosome 18q and gains at chromosome 2p13-25, 5p15, 5q21-35, 7, 8q24, 9q, 11, 12p, 14q24-32 and 20. Analysis by fluorescence in situ hybridization showed the deletion at 7qtel and duplication at 7q11.2 at the rearranged chromosome 7. Growth of TMC-1 cells was inhibited by 27-32% by interferon-alpha (2,000 U/ml) and by interferon-gamma with an IC50 of 125 U/ml. The cell line is tumorigenic in vivo, and its growth is moderately inhibited by interferon-alpha and interferon-gamma. It can be used to develop new modalities of human gastric cancer treatment.     

Biochemical characterization of interleukin 1 from a human monocytic cell line

A protein with interleukin 1 (IL-1) activity was obtained from the human acute monocytic leukemia cell line (THP-1) and purified by ultrafiltration, Ultrogel AcA54 chromatography, isoelectric focusing, and discontinuous polyacrylamide gel electrophoresis. Like the pI 6.8 species of IL-1 from human peripheral blood monocytes (PBM), the cell line IL-1 has a molecular weight (MW) of 14,000, a pI of 6.8, is heat labile, and does not bind to concanavalin A-Sepharose. Chemical modification of arginine residues by phenylglyoxal or sulfhydryl groups by N-ethyl maleimide and iodoacetamide completely destroys the activity of IL-1 from THP-1 cells as well as that of the pI 6.8 component from PBM. In contrast, the pI 5.1 component of PBM IL-1 is resistant to heat denaturation and sulfhydryl reagents, although it is totally inactivated by phenylglyoxal. IL-1 from THP-1 cells enhanced the proliferative response of the same subpopulations of PNA- thymocytes as IL-1 from PBM. These observations suggest that IL-1 derived from this cell line is similar to the IL-1 pI 6.8 species produced by human monocytes, and distinct from the pI 5.1 species.     

Phenotypic and functional characterization of a Sézary cell

We have studied the surface antigen pattern, enzymatic phenotype, and functional capacity of peripheral blood lymphocytes from a patient with Sézary syndrome (SS). The majority of these cells formed E rosettes but lacked the Fc() receptor. The neoplastic cells were reactive with pan-T cell (OKT3)- and helper T cell (OKT4)-subset monoclonal antibodies; however, they lacked the 5/9 antigen, which identifies a more restricted subset of helper T cells. Most SS cells also reacted with PTF 29.12, a monoclonal antibody which recognizes DR determinants. Only 35% of the cells expressed single, focal accumulations of -naphthyl-acid esterase activity, which is a characteristic of T._M cells, but 85% of them showed this focal staining pattern with acid phosphatase or -glucuronidase. Mononuclear cells from the SS patient showed poor or no proliferative response to phytohemagglutinin, pokeweed mitogen, concanavalin A, purified protein derivative, Candida, and allogeneic cells and lacked both helper and suppressor activity for pokeweed mitogen driven production of IgM and IgG immunoglobulins by normal B cells, but they were able to stimulate a marked proliferative response in mixed-lymphocyte culture. The defective expression of enzymatic and surface membrane characteristics, together with the lack of some T-cell functions, suggests that the patient cells may be immature T._M lymphocytes.     

Phenotypic and functional characterization of a new human macrophage cell line K1m demonstrating immunophagocytic activity and signalling through HLA class II.

A human macrophage line, designated K1m, has been established from peripheral blood. K1m expresses a number of lineage-specific markers as well as a broad array of intercellular adhesion molecules. In particular, K1m expresses high levels of human leucocyte antigen (HLA) class I and class II. In response to ligation of HLA class II (HLA-DR), but not in response to ligation of HLA class 1, K1m forms tighter homotypic aggregates and develops a striking ''stellate'' culture phenotype. K1m also expresses Fc receptors for immunoglobulin G (IgG) (CD64, CD32, and CD16) and can be shown to phagocytose polystyrene latex beads, as well as neuroblastoma cells in the presence of tumour-specific monoclonal antibody (mAb). The K1m cell line should therefore prove useful for studying both signalling through macrophage HLA class II and immunophagocytosis.     

Phenotypic and ultrastructural characterization of an epithelial cell line established from rat thymic cultures.

An epithelial cell line (TE-R 2.5) was established from a long-term culture of rat thymic epithelium. Its epithelial nature was confirmed using anti-cytokeratin (CK) monoclonal antibodies (mAb) and electron-microscopy. TE-R 2.5 cells were reactive with K 8.13, K 8.12, CK 8, R-MC 18, R-MC 19 and Mar 3 mAb and bind Ulex europaeus agglutinin I. Based on the results of this study it was concluded that they possess the phenotype of subcapsular/perivascular or medullary epithelium. This was in accordance with Western blot analysis of water-insoluble cell extracts showing the presence of 56,000, 52,000, 50,000 and 48,000 MW CK polypeptides. In addition, TE-R 2.5 cell line coexpressed CK and vimentin (a 57,000 MW polypeptide) which was demonstrated using dual immunohistochemistry and Western blot analysis. Electron microscopy demonstrated that TE-R 2.5 cells have all the characteristics of hypertrophic thymic epithelial cells (TEC) localized in situ exclusively in the medulla and thus further characterized this line as a type of medullary TEC. Finally, TE-4F10 mAb raised against an antigen of TE-R 2.5 cells selectively stained a subset of medullary TEC in situ including Hassall's corpuscles indicating again the medullary origin of this TEC line.     

The alpha-bungarotoxin receptor purified from a human neuroblastoma cell line: biochemical and immunological characterization

The pharmacological and electrophysiological characteristics of the alpha-bungarotoxin receptor present on the human neuroblastoma cell line IMR-32 indicate that this receptor is not associated with an acetylcholine-operated ionic channel. In this paper we report its biochemical purification and immunological characterization. This molecule has a standard sedimentation coefficient of 10S and sodium dodecyl-sulphate gel electrophoresis shows that it is made up of three polypeptide chains of molecular weights of 67,000, 60,000 and 52,000. Ligand binding to blots of purified receptor revealed that only the polypeptide of molecular weight 52,000 is bound by [125I]alpha-bungarotoxin. The purified alpha-bungarotoxin receptor was bound by polyclonal antibodies raised against purified fetal calf, Torpedo and chick optic lobe nicotinic receptors and by the sera of myasthenic patients. Furthermore, despite the fact that a number of different immunological techniques were used, it was impossible to label this alpha-bungarotoxin receptor with mAb 35, a monoclonal antibody which binds some neuronal nicotinic receptors. Rabbit antisera against the purified alpha-bungarotoxin receptor were used to compare this protein with other known nicotinic receptors and, once again, it was demonstrated that there is some immunological cross-reactivity between the alpha-bungarotoxin receptor present on neuroblastoma cells and Torpedo, fetal calf and chick optic lobe nicotinic receptors. All these immunological data, together with previously published pharmacological and molecular biology data, demonstrate that the alpha-bungarotoxin receptor present in nerve cells is neither a muscular nor a neuronal nicotinic receptor, although it has similarities with both.     

The interplay between cell adhesion cues and curvature of cell adherent alginate microgels in multipotent stem cell culture

Cell-adherent microcarriers are increasingly used to expand multipotent stem cells on a large scale for therapeutic applications. However, the role of the microcarrier properties and geometry on the phenotypic activities of multipotent cells has not been well studied. This study presents a significant interplay of the number of cell adhesion sites and the curvature of the microcarrier in regulating cell growth and differentiation by culturing mesenchymal stem cells on alginate microgels chemically linked with oligopeptides containing the Arg-Gly-Asp (RGD) sequence. Interestingly, the cell growth rate and osteogenic differentiation level were increased with the RGD peptide density. At a given RGD peptide density, the cell growth rate was inversely related to the microgel diameter, whereas the osteogenic differentiation level was minimally influenced. The dependency of the cell growth rate on the microgel diameter was related to changes in shear stresses acting on cells according to simulation. Overall, this study identifies material variables key to regulating cellular activities on microcarriers, and these findings will be useful to designing a broad array of bioactive microcarriers.     

Synthesis and transport characterization of alginate/aminopropyl-silicate/alginate microcapsule: application to bioartificial pancreas

To develop a novel type of immunoisolation membrane for a microcapsule-shaped bioartificial pancreas, we attempted to use a sol-gel synthesized silicate. An aminopropyl-silicate membrane derived from 3-aminopropyltrimethoxysilane and tetramethoxysilane was formed on Ca-alginate gel beads via electrostatic interaction. The positively charged amino groups remaining on the surface of the resultant gel beads were neutralized by immersion in an aqueous Na-alginate solution. From measurements of the partition coefficients and effective diffusivities of different substances to the gel beads, it was found that the aminopropyl-silicate membrane prepared under optimized composition of silicon alkoxide precursors successfully rejected gamma-globulin, giving good permeability to substances having a low molecular weight. Islets could be encapsulated within the newly developed microcapsules while retaining their ability to secrete insulin.     

Establishment and characterization of human metastatic hepatocellular carcinoma cell line

Hepatocellular carcinoma (HCC) is one of the most common malignancies worldwide with a poor prognosis. Recently, we established a HCC cell line from a metastatic HCC tumor. GTG banding analysis was performed and the karyotype showed that this metastatic HCC cell line is a hypertriploid (71-78 chromosomes) with a large marker chromosome containing a long homogeneously staining region (hsr). Comparative genomic hybridization was applied to characterize the chromosomal alterations in this metastatic HCC cell line. The results showed that the hsr was composed of amplified DNA sequences from 11q13. Further characterization of the hsr may lead to the isolation of the putative amplified oncogene at 11q13.     

人肺腺癌厄洛替尼耐药细胞系PC-9/ER的建立及其特性

目的：构建厄洛替尼耐药人肺腺癌细胞模型PC-9/ER,观察单用人表皮生长因子受体(epithelial growth factor receptor,EGFR)酪氨酸激酶抑制剂厄洛替尼或联合胰岛素样生长因子受体1(insulin-like growth factor receptor 1,IGF1R)酪氨酸激酶抑制剂苦鬼臼毒(picropodophyllotoxin,PPP)作用于该细胞后,该细胞对厄洛替尼耐药性的影响,并探讨耐药相关机制。方法：选择人肺腺癌细胞株PC-9,采用逐步递增厄洛替尼浓度的方法体外诱导构建耐药株PC-9/ER。CCK-8法检测耐药指数;细胞计数法绘制PC-9和PC-9/ER的生长曲线,并计算出两细胞系的倍增时间;流式细胞术检测两细胞系的细胞周期;Western Blot法检测p-EGFR及p-IGF1R的表达水平,并进一步检测厄洛替尼及PPP单独或联合作用于PC-9/ER后,各组Akt,ERK,p-Akt及p-ERK的表达水平。结果：PC-9/ER细胞株的耐药指数是72.3。细胞生长曲线显示,PC-9/ER细胞生长较亲代细胞慢,PC-9与PC-9/ER细胞的倍增时间分别为32.9及36.9 h (P=0.003)。与PC-9相比,PC-9/ER细胞的G1期细胞增多(P=0.001),而S期细胞则明显下降(P=0.015)。Western Blot结果表明,PC-9/ER细胞中p-IGF1R表达比亲代细胞明显增多(P=0.016),而p-EGFR无明显变化(P=0.152)。在亲代及耐药细胞系,厄洛替尼联合PPP组均较其他组更能显著的抑制细胞增殖(P<0.05);且Western Blot法表明联合用药组EGFR下游磷酸化的Akt、ERK的表达水平明显减少。结论：成功构建了人肺腺癌厄洛替尼耐药细胞株PC-9/ER,IGF1R通路可能与肺腺癌EGFR-TKI获得性耐药有关。     

The effect of intracellular alkalinisation on intracellular Ca(2+) homeostasis in a human chondrocyte cell line

Intracellular pH (pH(i)) is a well-established determinant of cartilage matrix metabolism. Changes to chondrocyte pH(i), and therefore matrix turnover rates, arise following joint loading. It is not yet clear whether pH changes exert their effects on matrix metabolism directly, or by changing the concentration of another, as yet unidentified, intracellular factor. In this study the effect of intracellular alkalinisation on intracellular [Ca(2+)] has been examined using the human chondrocyte C-20/A4 cell line. pH(i) was manipulated by the addition of weak bases to suspensions of chondrocytes and fluorimetric techniques were employed to measure pH(i) and [Ca(2+)](i). The effect of pH(i) changes on intracellular inositol 1,4,5-trisphosphate (IP(3)) levels was also determined. The pH-sensitive properties of the Ca(2+)-sensitive fluoroprobe employed in this study, Fura-2, were investigated such that artefactual effects of pH changes upon the dye could be discounted. It was demonstrated that, for dye loaded into cells, alkalinisation resulted in a small increase in the affinity of the dye for Ca(2+) ions. Intracellular alkalinisation elicited by treatment with either of the weak bases trimethylamine or ammonium chloride initiated a rise in [Ca(2+)](i). This effect was too large to be explicable by the effects of pH changes on Fura-2 and was not dependent on the presence of extracellular Ca(2+) ions. Prior depletion of intracellular Ca(2+) stores by treatment with thapsigargin inhibited alkalinisation-induced increases in [Ca(2+)](i) and intracellular alkalinisation was also associated with increased levels of intracellular IP(3). These results confirm that alkaline pH(i) changes associated with dynamic loading of cartilage also result in knock-on alterations to [Ca(2+)](i). Given the sensitivity of cartilage matrix metabolism to [Ca(2+)](i) it is likely that this signalling cascade forms an important part of the mechanotransduction pathway that determines the response of chondrocytes to applied load.