Heparan sulfates of cultured cells. II. Acid-soluble and -precipitable species of different cell lines

Biochemistry ◽  
1971 ◽  
Vol 10 (8) ◽  
pp. 1445-1451 ◽  
Author(s):  
Paul M. Kraemer
Author(s):  
Yoshino Tanaka ◽  
Yoshihiko Nanasato ◽  
Kousei Omura ◽  
Keita Endoh ◽  
Tsuyoshi Kawano ◽  
...  

Abstract Polyhistidine peptides (PHPs), sequences comprising only histidine residues (>His8), are effective cell-penetrating peptides for plant cells. Using PHP-fusion proteins, we aimed to deliver proteins into cultured plant cells from Nicotiana tabacum, Oryza sativa, and Cryptomeria japonica. Co-cultivation of cultured cells with fusion proteins combining maltose-binding protein (MBP), red fluorescent protein (RFP), and various PHPs (MBP-RFP-His8–His20) in one polypeptide showed the cellular uptake of fusion proteins in all plant cell lines. Maximum intracellular fluorescence was shown in MBP-RFP-His20. Further, adenylate cyclase (CyaA), a synthase of cyclic adenosine monophosphate (cAMP) activated by cytosolic calmodulin, was used as a reporter for protein delivery in living cells. A fusion protein combining MBP, RFP, CyaA, and His20 (MBP-RFP-CyaA-His20) was delivered into plant cells and increased intracellular fluorescence and cAMP production in all cell lines. The present study demonstrates that PHPs are effective carriers of proteins into the intracellular space of various cultured plant cells.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Alessandro T. Caputo ◽  
Oliver M. Eder ◽  
Hana Bereznakova ◽  
Heleen Pothuis ◽  
Albert Ardevol ◽  
...  

AbstractPuromycin and the Streptomyces alboniger-derived puromycin N-acetyltransferase (PAC) enzyme form a commonly used system for selecting stably transfected cultured cells. The crystal structure of PAC has been solved using X-ray crystallography, revealing it to be a member of the GCN5-related N-acetyltransferase (GNAT) family of acetyltransferases. Based on structures in complex with acetyl-CoA or the reaction products CoA and acetylated puromycin, four classes of mutations in and around the catalytic site were designed and tested for activity. Single-residue mutations were identified that displayed a range of enzymatic activities, from complete ablation to enhanced activity relative to wild-type (WT) PAC. Cell pools of stably transfected HEK293 cells derived using two PAC mutants with attenuated activity, Y30F and A142D, were found to secrete up to three-fold higher levels of a soluble, recombinant target protein than corresponding pools derived with the WT enzyme. A third mutant, Y171F, appeared to stabilise the intracellular turnover of PAC, resulting in an apparent loss of selection stringency. Our results indicate that the structure-guided manipulation of PAC function can be utilised to enhance selection stringency for the derivation of mammalian cell lines secreting elevated levels of recombinant proteins.


2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Youngil Koh ◽  
Woo-June Jung ◽  
Kwang-Sung Ahn ◽  
Sung-Soo Yoon

Purpose.We tried to establish clinically relevant human myeloma cell lines that can contribute to the understanding of multiple myeloma (MM).Materials and Methods.Mononuclear cells obtained from MM patient’s bone marrow were injected via tail vein in an NRG/SCID mouse. Fourteen weeks after the injection, tumor developed at subcutis of the mouse. The engraftment of MM cells into mouse bone marrow (BM) was also observed. We separated and cultured cells from subcutis and BM.Results.After the separation and culture of cells from subcutis and BM, we established two cell lines originating from a single patient (SNU_MM1393_BM and SNU_MM1393_SC). Karyotype of the two newly established MM cell lines showed tetraploidy which is different from the karyotype of the patient (diploidy) indicating clonal evolution. In contrast to SNU_MM1393_BM, cell proliferation of SNU_MM1393_SC was IL-6 independent. SNU_MM1393_BM and SNU_MM1393_SC showed high degree of resistance against bortezomib compared to U266 cell line. SNU_MM1393_BM had the greater lethality compared to SNU_MM1393_SC.Conclusion.Two cell lines harboring different site tropisms established from a single patient showed differences in cytokine response and lethality. Our newly established cell lines could be used as a tool to understand the biology of multiple myeloma.


1993 ◽  
Vol 104 (4) ◽  
pp. 1187-1197 ◽  
Author(s):  
R.W. Dirks ◽  
F.M. van de Rijke ◽  
S. Fujishita ◽  
M. van der Ploeg ◽  
A.K. Raap

We have determined optimal conditions for the detection of mRNA sequences in cultured cells by nonradioactive in situ hybridization. For this purpose a number of different cell lines have been used: rat 9G cells for the detection of human cytomegalovirus immediate early mRNA, and HeLa as well as 5637 carcinoma cells for the detection of housekeeping gene mRNAs. Extensive optimization of fixation and pretreatment conditions revealed that most intense hybridization signals are obtained when cells are grown on glass microscope slides, fixed with a mixture of formaldehyde and acetic acid, pretreated with pepsin and denatured prior to hybridization. In addition, we also studied the potential of fluorochromized probes for the direct detection of multiple RNA sequences. The optimized in situ hybridization procedure revealed that immediate early mRNA transcripts are, in addition to a cytoplasmic localization, localized within nuclei of rat 9G cells. Double hybridization experiments showed that intron and exon sequences colocalize within the main nuclear signal. In addition, the presence of small, intron-specific, fluorescent spots scattered around the main nuclear signals indicates that intron sequences which are spliced out can be visualized. Additional information about the functioning of cells could be obtained by the detection of mRNA simultaneously with bromodeoxyuridine, incorporated during S-phase, or its cognate protein. The sensitivity of these methods is such that mRNAs of abundantly expressed housekeeping genes can be detected in a variety of cell lines with high signal to noise ratios.


1993 ◽  
Vol 13 (9) ◽  
pp. 5670-5678
Author(s):  
S Schuetze ◽  
P E Stenberg ◽  
D Kabat

In vivo studies of Friend virus erythroleukemia have implied that proviral integrations adjacent to the gene for the Ets-related transcription factor PU.1 may inhibit the commitment of erythroblasts to differentiate and cause their capability for indefinite transplantation (C. Spiro, B. Gliniak, and D. Kabat, J. Virol. 62:4129-4135, 1988; R. Paul, S. Schuetze, S. L. Kozak, C. Kozak, and D. Kabat, J. Virol. 65:464-467, 1991). To test this hypothesis, we ligated PU.1 cDNA into a retroviral vector and studied its effects on cultured cells. Infection of fibroblasts with PU.1-encoding retrovirus resulted in PU.1 synthesis followed by nuclear pyknosis, cell rounding, and degeneration. In contrast, in long-term bone marrow cultures, erythroblasts were efficiently and rapidly immortalized. The resulting cell lines were polyclonal populations that contained PU.1, were morphologically blast-like, required erythropoietin and bone marrow stromal cells for survival and proliferation, and spontaneously differentiated at low frequency to synthesize hemoglobin. After 9 months in culture, erythroblasts became stroma independent, and they then grew as clonal cell lines. We conclude that PU.1 perturbs the pathway(s) that controls potential for indefinite proliferation and that it can be used to generate permanent erythroblast cell lines.


2005 ◽  
Vol 17 (2) ◽  
pp. 167 ◽  
Author(s):  
A.M. Giraldo ◽  
J.W. Lynn ◽  
C.E. Pope ◽  
R.A. Godke ◽  
K.R. Bondioli

The low efficiency of nuclear transfer (NT) has been related to factors such as mitochondria heteroplasmy, failure of genomic activation, and asynchrony between the donor karyoplast and recipient cytoplast. Few studies have characterized donor cell lines in terms of proliferative capacity and chromosomal stability. It is known that suboptimal culture conditions can induce chromosomal abnormalities, and the use of aneuploid donor cells during NT can lead to a high incidence of abnormal cloned embryos (Giraldo et al. 2004 Reprod. Fertil. Dev. 16, 124 abst). The purpose of this study was to determine the lifespan and chromosomal stability of bovine and porcine fetal cells. Four bovine and four porcine fibroblast cells lines were established from 50-day and 40-day fetuses, respectively. Cells were cultured in DMEM medium supplemented with 10% fetal bovine serum and 1% penicillin and streptomycin at 37°C in 5% CO2. Each cell line was passaged to senescence. Total population doublings (PDs) and cell cycle duration were calculated. To determine the chromosome numbers at different PDs, cells were synchronized in metaphase, fixed, and stained. ANOVA and chi-square tests were used to analyze differences in PDs and proportion of aneuploid cells between cell lines, respectively (P < 0.05). The results show that proliferative capacity was not different between cell lines derived from the same species. Cell lines derived from bovine and porcine fetuses had different in vitro lifespans (33 PDs vs. 42 PDs, respectively; P < 0.05). The mean length of the cell cycles for both bovine and porcine fetal fibroblasts was ∼28 h. The percentage of aneupliod cells in both bovine and porcine fetal cell lines increased progressively with duration of culture (see Table) and was high throughout the study. The proliferative capacity of cultured cells was similar within individuals of the same species, but growth characteristics differed between fetal bovine and porcine cell lines. The progressive increase of aneuploid cells could be due to suboptimal culture conditions or unusual chromosome instability in the particular fetuses used. These data demonstrate the importance of determining chromosome content and the use of cells at early passages to decrease the percentage of aneuploid reconstructed embryos and increase the efficiency of NT.


Blood ◽  
1987 ◽  
Vol 70 (5) ◽  
pp. 1303-1311 ◽  
Author(s):  
K Krichbaum-Stenger ◽  
BJ Poiesz ◽  
P Keller ◽  
G Ehrlich ◽  
J Gavalchin ◽  
...  

In this report, we describe a flow cytometric analysis of HTLV-I specific binding to fresh and cultured cells on a single cell basis. This assay uses rhodamine hydrocarbon tagged, purified HTLV-I virions according to the procedure originally described for avian retroviruses. Successful HTLV-I transmission was detected by analysis of integrated HTLV-I DNA, virion-associated reverse transcriptase, and/or intracellular HTLV-I core antigen p19 expression. Only a specific virus- cell interaction was detected because nonrhodamine-tagged homologous virus or related HTLV-II interfered with tagged HTLV-I binding. In contrast, an unrelated, nonlabeled animal retrovirus was unable to block tagged HTLV binding. Of the cell lines tested, 2 nonlymphoid mammalian and 3 human lymphoid bound significantly high to moderate levels of HTLV-I-tagged virions. The other three human lymphocyte cell lines were insensitive to HTLV-I adsorption. A direct correlation was observed between HTLV-I binding sites and infectivity of human lymphoid cells alone and not other nonlymphoid animal cells. Fresh normal human mononuclear cells bound low levels of HTLV-I virions. As expected, T lymphocytes demonstrated more binding than did the non-T cell population. Enhancement of HTLV-I cell binding in a subpopulation of mononuclear target cells was achieved with phytohemagglutinin (PHA) activation and interleukin 2 (IL2) stimulation, which correlates well with previously published infectivity studies.


1993 ◽  
Vol 104 (3) ◽  
pp. 695-704 ◽  
Author(s):  
N. Cartier ◽  
R. Lacave ◽  
V. Vallet ◽  
J. Hagege ◽  
R. Hellio ◽  
...  

Targeted oncogenesis allowed us to obtain two cell lines which have been derived from the proximal tubule of kidney from transgenic mice harbouring the simian virus (SV40) large T and small t antigens placed under the control of the 5′ regulatory sequence from the rat L-type pyruvate kinase (L-PK) gene. The cell lines (PKSV-PCT and PKSV-PR cells) were derived from early (PCT) and late (Pars Recta, PR) microdissected proximal tubules grown in D-glucose-enriched medium. In such conditions of culture, both cell lines exhibited L-PK transcripts, a stable expression of SV40-encoded nuclear large T antigen, a prolonged life span but failed to induce tumors when injected sub-cutaneously into athymic (nu-nu) mice. Confluent cells, grown on plastic support or porous filters, were organized as monolayers of polarized cuboid cells with well developed apical microvilli and formed domes. Both cell lines exhibited morphological features of proximal tubule cells with villin located in the apical brush-border and substantial amounts of hydrolase activity. By immunofluorescence studies using specific antibodies, aminopeptidase N appeared restricted to the apical microvillar domain, whereas the H2 histocompatibility antigen was distributed in the cytoplasm and lateral membranes. These results demonstrate that the proximal morphological phenotype has been fully preserved in these cultured cells derived from tissue-specific targeted oncogenesis in transgenic mice.


1993 ◽  
Vol 13 (9) ◽  
pp. 5670-5678 ◽  
Author(s):  
S Schuetze ◽  
P E Stenberg ◽  
D Kabat

In vivo studies of Friend virus erythroleukemia have implied that proviral integrations adjacent to the gene for the Ets-related transcription factor PU.1 may inhibit the commitment of erythroblasts to differentiate and cause their capability for indefinite transplantation (C. Spiro, B. Gliniak, and D. Kabat, J. Virol. 62:4129-4135, 1988; R. Paul, S. Schuetze, S. L. Kozak, C. Kozak, and D. Kabat, J. Virol. 65:464-467, 1991). To test this hypothesis, we ligated PU.1 cDNA into a retroviral vector and studied its effects on cultured cells. Infection of fibroblasts with PU.1-encoding retrovirus resulted in PU.1 synthesis followed by nuclear pyknosis, cell rounding, and degeneration. In contrast, in long-term bone marrow cultures, erythroblasts were efficiently and rapidly immortalized. The resulting cell lines were polyclonal populations that contained PU.1, were morphologically blast-like, required erythropoietin and bone marrow stromal cells for survival and proliferation, and spontaneously differentiated at low frequency to synthesize hemoglobin. After 9 months in culture, erythroblasts became stroma independent, and they then grew as clonal cell lines. We conclude that PU.1 perturbs the pathway(s) that controls potential for indefinite proliferation and that it can be used to generate permanent erythroblast cell lines.


Intervirology ◽  
2015 ◽  
Vol 58 (2) ◽  
pp. 69-72 ◽  
Author(s):  
Veronika Mrázová ◽  
Tatiana Betáková ◽  
Marcela Kúdelová ◽  
Miroslava Šupolíková ◽  
Veronika Lachová ◽  
...  

Human dermal fibroblasts and mouse NIH/3T3 cells acquired the transformed phenotype (‘criss-cross' pattern of growth) after infection with ultraviolet-irradiated murine gammaherpesvirus (MuHV-4 strain 68; MHV-68). These cells with changed phenotype could be serially cultured for 5-6 passages (35-40 days), and then they entered into crisis and most of them died. In a small number of cultures, however, foci of newly transformed cells appeared from which two stable cell lines were derived. After 6-9 cell culture passages of the MHV-68 transformed cell lines, MHV-68 DNA and virus antigen could be detected by PCR and immunofluorescence assay along with the disappearance of actin bundles, indicating that both transformed cell lines might be oncogenic.


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