Identification of SlpB, a Cytotoxic Protease from Serratia marcescens

The Gram-negative bacterium and opportunistic pathogenSerratia marcescenscauses ocular infections in healthy individuals. Secreted protease activity was characterized from 44 ocular clinical isolates, and a higher frequency of protease-positive strains was observed among keratitis isolates than among conjunctivitis isolates. A positive correlation between protease activity and cytotoxicity to human corneal epithelial cellsin vitrowas determined. Deletion ofprtSin clinical keratitis isolate K904 reduced, but did not eliminate, cytotoxicity and secreted protease production. This indicated that PrtS is necessary for full cytotoxicity to ocular cells and implied the existence of another secreted protease(s) and cytotoxic factors. Bioinformatic analysis of theS. marcescensDb11 genome revealed three additional open reading frames predicted to code for serralysin-like proteases noted here asslpB,slpC, andslpD. Induced expression ofprtSandslpB, but notslpCandslpD, in strain PIC3611 rendered the strain cytotoxic to a lung carcinoma cell line; however, onlyprtSinduction was sufficient for cytotoxicity to a corneal cell line. Strain K904 with deletion of bothprtSandslpBgenes was defective in secreted protease activity and cytotoxicity to human cell lines. PAGE analysis suggests that SlpB is produced at lower levels than PrtS. Purified SlpB demonstrated calcium-dependent and AprI-inhibited protease activity and cytotoxicity to airway and ocular cell linesin vitro. Lastly, genetic analysis indicated that the type I secretion system gene,lipD, is required for SlpB secretion. These genetic data introduce SlpB as a new cytotoxic protease fromS. marcescens.

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Phenotypic heterogeneity among stromal cell lines from mouse bone marrow disclosed in their extracellular matrix composition and interactions with normal and leukemic cells

Blood ◽

10.1182/blood.v66.2.447.447 ◽

1985 ◽

Vol 66 (2) ◽

pp. 447-455 ◽

Cited By ~ 66

Author(s):

D Zipori ◽

J Toledo ◽

K von der Mark

Keyword(s):

Bone Marrow ◽

Extracellular Matrix ◽

Cell Line ◽

Cell Lines ◽

Stromal Cell ◽

Leukemic Cells ◽

Matrix Composition ◽

Mouse Bone Marrow ◽

Type I

Abstract Study of a series of stromal cell lines from mouse bone marrow (MBA) verified and extended their classification as phenotypically distinct subtypes. Production of extracellular matrix proteins was examined using specific antibodies. Fibronectin and laminin were detected in all of the cell lines tested, yet 14F1.1 adipocytes exhibited particularly prominent extracellular deposition. This cell line and MBA-13.2 cells were positive to both collagen types I and IV, whereas MBA-1 and MBA- 2.1 were stained with anticollagen type I antibodies only. Coculture experiments revealed differences among the lines in their effects on normal myeloid cells and leukemic cell lines. In promoting the in vitro accumulation of myeloid progenitors (CFU-C), 14F1.1 cells surpassed the others. The MBA-2.1 cell line was particularly inhibitory to MPC-11 plasmacytoma and Friend erythroleukemia cells. However, the latter were refractory to other stromal cell lines, whereas MPC-11 cells were inhibited to various degrees by virtually all of the cell lines. Physical separation between the interacting cells reduced the inhibition in some but not all cases, and no inhibitory activity was detected in conditioned media. The MBA-13 stromal cells synergistically promoted the differentiation of dimethylsulfoxide (Me2SO)-induced Friend erythroleukemia. The latter cells themselves, at high concentrations, as well as some of the stromal cell lines and unrelated adherent cells, antagonized the Me2SO effect, revealing possible reversible stages in the Friend cell differentiation pathway.

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Aortic endothelial cell heterogeneity in vitro. Lack of association between morphological phenotype and collagen biosynthesis

Journal of Cell Science ◽

10.1242/jcs.102.4.807 ◽

1992 ◽

Vol 102 (4) ◽

pp. 807-814

Author(s):

A.E. Canfield ◽

F.E. Wren ◽

S.L. Schor ◽

M.E. Grant ◽

A.M. Schor

Keyword(s):

Endothelial Cells ◽

Cell Line ◽

Cell Lines ◽

Type I Collagen ◽

Protein Biosynthesis ◽

Significant Degree ◽

Type I ◽

Cell Phenotypes ◽

Aortic Endothelial

Previous reports dealing with the characterisation of endothelial cells derived from the same tissue have produced apparently conflicting results in fundamental cellular attributes such as matrix biosynthesis and the ability to form sprouts in vitro. One potential explanation for this discrepancy is that endothelial cells actually comprise a heterogeneous population of cells displaying a significant degree of intra-site variation in phenotype. In order to address this question, we have characterised both cloned and uncloned lines of bovine aortic endothelial cells with respect to (a) their ability to adopt both the cobblestone and sprouting cell phenotypes and (b) matrix biosynthesis by cells displaying these two phenotypes. Data are presented indicating that all of the 18 cloned and 20 uncloned cell lines examined were capable of undergoing a reversible transition between the cobblestone and sprouting cell phenotypes in response to culture conditions. In all cases, sprouting occurred spontaneously in the presence of either serum or platelet-poor plasma and did not require the addition of exogenous factors to the medium. Twelve lines of cells were examined with respect to protein biosynthesis; these lines produced different types of collagens in differing proportions. The pattern of collagen synthesis displayed by every cell line was stable and did not vary with either passage number or batch of serum. The presence of a 3-D gel of native type I collagen increased specifically the synthesis of type IV collagen by one cell line. However, in four other cell lines, even though total synthesis was increased, the type of proteins secreted by these cells was not altered.(ABSTRACT TRUNCATED AT 250 WORDS)

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Phenotypic heterogeneity among stromal cell lines from mouse bone marrow disclosed in their extracellular matrix composition and interactions with normal and leukemic cells

Blood ◽

10.1182/blood.v66.2.447.bloodjournal662447 ◽

1985 ◽

Vol 66 (2) ◽

pp. 447-455

Author(s):

D Zipori ◽

J Toledo ◽

K von der Mark

Keyword(s):

Bone Marrow ◽

Extracellular Matrix ◽

Cell Line ◽

Cell Lines ◽

Stromal Cell ◽

Leukemic Cells ◽

Matrix Composition ◽

Mouse Bone Marrow ◽

Type I

Study of a series of stromal cell lines from mouse bone marrow (MBA) verified and extended their classification as phenotypically distinct subtypes. Production of extracellular matrix proteins was examined using specific antibodies. Fibronectin and laminin were detected in all of the cell lines tested, yet 14F1.1 adipocytes exhibited particularly prominent extracellular deposition. This cell line and MBA-13.2 cells were positive to both collagen types I and IV, whereas MBA-1 and MBA- 2.1 were stained with anticollagen type I antibodies only. Coculture experiments revealed differences among the lines in their effects on normal myeloid cells and leukemic cell lines. In promoting the in vitro accumulation of myeloid progenitors (CFU-C), 14F1.1 cells surpassed the others. The MBA-2.1 cell line was particularly inhibitory to MPC-11 plasmacytoma and Friend erythroleukemia cells. However, the latter were refractory to other stromal cell lines, whereas MPC-11 cells were inhibited to various degrees by virtually all of the cell lines. Physical separation between the interacting cells reduced the inhibition in some but not all cases, and no inhibitory activity was detected in conditioned media. The MBA-13 stromal cells synergistically promoted the differentiation of dimethylsulfoxide (Me2SO)-induced Friend erythroleukemia. The latter cells themselves, at high concentrations, as well as some of the stromal cell lines and unrelated adherent cells, antagonized the Me2SO effect, revealing possible reversible stages in the Friend cell differentiation pathway.

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Pathogenicity of Serratia marcescens Strains in Honey Bees

mBio ◽

10.1128/mbio.01649-18 ◽

2018 ◽

Vol 9 (5) ◽

Cited By ~ 24

Author(s):

Kasie Raymann ◽

Kerri L. Coon ◽

Zack Shaffer ◽

Stephen Salisbury ◽

Nancy A. Moran

Keyword(s):

Serratia Marcescens ◽

Honey Bee ◽

Honey Bees ◽

Opportunistic Pathogen ◽

The United States ◽

Bacterial Cells ◽

Content Type ◽

Varroa Mites ◽

Bee Decline

ABSTRACT Although few honey bee diseases are known to be caused by bacteria, pathogens of adult worker bees may be underrecognized due to social immunity mechanisms. Specifically, infected adult bees typically abandon the hive or are removed by guards. Serratia marcescens, an opportunistic pathogen of many plants and animals, is often present at low abundance in the guts of honey bee workers and has recently been isolated from Varroa mites and from the hemolymph of dead and dying honey bees. However, the severity and prevalence of S. marcescens pathogenicity in honey bees have not been fully investigated. Here we characterized three S. marcescens strains isolated from the guts of honey bees and one previously isolated from hemolymph. In vivo tests confirmed that S. marcescens is pathogenic in workers. All strains caused mortality when a few cells were injected into the hemocoel, and the gut-isolated strains caused mortality when administered orally. In vitro assays and comparative genomics identified possible mechanisms of virulence of gut-associated strains. Expression of antimicrobial peptide and phenoloxidase genes was not elevated following infection, suggesting that these S. marcescens strains derived from honey bees can evade the immune response in their hosts. Finally, surveys from four locations in the United States indicated the presence of S. marcescens in the guts of over 60% of the worker bees evaluated. Taken together, these results suggest that S. marcescens is a widespread opportunistic pathogen of adult honey bees and that it may be highly virulent under some conditions such as perturbation of the normal gut microbiota or the presence of Varroa mites that puncture the integument, thereby enabling entry of bacterial cells. IMPORTANCE Recently, it has become apparent that multiple factors are responsible for honey bee decline, including climate change, pests and pathogens, pesticides, and loss of foraging habitat. Of the large number of pathogens known to infect honey bees, very few are bacteria. Because adult workers abandon hives when diseased, many of their pathogens may go unnoticed. Here we characterized the virulence of Serratia marcescens strains isolated from honey bee guts and hemolymph. Our results indicate that S. marcescens, an opportunistic pathogen of many plants and animals, including humans, is a virulent opportunistic pathogen of honey bees, which could contribute to bee decline. Aside from the implications for honey bee health, the discovery of pathogenic S. marcescens strains in honey bees presents an opportunity to better understand how opportunistic pathogens infect and invade hosts.

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ANTITUMOR EFFECT OF SUNITINIB AND BORTEZOMIB ON BREAST CANCER CELL LINE IN VITRO

Problems in oncology ◽

10.37469/0507-3758-2017-63-1-141-145 ◽

2017 ◽

Vol 63 (1) ◽

pp. 141-145

Author(s):

Yuliya Khochenkova ◽

Eliso Solomko ◽

Oksana Ryabaya ◽

Yevgeniya Stepanova ◽

Dmitriy Khochenkov

Keyword(s):

Breast Cancer ◽

Cell Line ◽

Cell Lines ◽

Cancer Cell ◽

Breast Cancer Cell ◽

Antitumor Effect ◽

Cancer Cell Lines ◽

Breast Cancer Cell Lines ◽

Actual Problem

The discovery for effective combinations of anticancer drugs for treatment for breast cancer is the actual problem in the experimental chemotherapy. In this paper we conducted a study of antitumor effect of the combination of sunitinib and bortezomib against MDA-MB-231 and SKBR-3 breast cancer cell lines in vitro. We found that bortezomib in non-toxic concentrations can potentiate the antitumor activity of sunitinib. MDA-MB-231 cell line has showed great sensitivity to the combination of bortezomib and sunitinib in vitro. Bortezomib and sunitinib caused reduced expression of receptor tyrosine kinases VEGFR1, VEGFR2, PDGFRa, PDGFRß and c-Kit on HER2- and HER2+ breast cancer cell lines

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Design, Synthesis, Molecular Docking, and Anticancer Evaluation of Pyrazole Linked Pyrazoline Derivatives with Carbothioamide Tail as EGFR Kinase Inhibitors

Anti-Cancer Agents in Medicinal Chemistry ◽

10.2174/1871520620666200727093613 ◽

2020 ◽

Vol 21 (1) ◽

pp. 42-60

Author(s):

Farah Nawaz ◽

Ozair Alam ◽

Ahmad Perwez ◽

Moshahid A. Rizvi ◽

Mohd. Javed Naim ◽

...

Keyword(s):

Molecular Docking ◽

Cell Line ◽

Cell Lines ◽

Cancer Cell ◽

Cancer Cell Line ◽

Cancer Cell Lines ◽

Kinase Assay ◽

Cervix Uteri ◽

Egfr Kinase

Background: The Epidermal Growth Factor Receptor (known as EGFR) induces cell differentiation and proliferation upon activation through the binding of its ligands. Since EGFR is thought to be involved in the development of cancer, the identification of new target inhibitors is the most viable approach, which recently gained momentum as a potential anticancer therapy. Objective: To assess various pyrazole linked pyrazoline derivatives with carbothioamide for EGFR kinase inhibitory as well as anti-proliferative activity against human cancer cell lines viz. A549 (non-small cell lung tumor), MCF-7 (breast cancer cell line), SiHa (cancerous tissues of the cervix uteri), and HCT-116 (colon cancer cell line). Methods: In vitro EGFR kinase assay, in vitro MTT assay, Lactate dehydrogenase release, nuclear staining (DAPI), and flow cytometry cell analysis. Results: Compounds 6h and 6j inhibited EGFR kinase at concentrations of 1.66μM and 1.9μM, respectively. Furthermore, compounds 6h and 6j showed the most potent anti-proliferative results against the A549 KRAS mutation cell line (IC50 = 9.3 & 10.2μM). Through DAPI staining and phase contrast microscopy, it was established that compounds 6h and 6j also induced apoptotic activity in A549 cells. This activity was further confirmed by FACS using Annexin-V-FITC and Propidium Iodide (PI) labeling. Molecular docking studies performed on 6h and 6j suggested that the compounds can bind to the hinge region of ATP binding site of EGFR tyrosine kinase in a similar pose as that of the standard drug gefitinib. Conclusion: The potential anticancer activity of compounds 6h and 6j was confirmed and need further exploration in cancer cell lines of different tissue origin and signaling pathways, as well as in animal models of cancer development.

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Survival and Function of Fibroblasts Stored as Stock Cultures at a Non-freezing Temperature

Alternatives to Laboratory Animals ◽

10.1177/026119299302100215 ◽

1993 ◽

Vol 21 (2) ◽

pp. 206-209

Author(s):

Anders H. G. Andrén ◽

Anders P. Wieslander

Keyword(s):

Cell Growth ◽

Cell Line ◽

Cell Lines ◽

Fibroblast Cell ◽

Freezing Temperature ◽

Mouse Fibroblast ◽

Toxic Response ◽

Normal Manner ◽

And Function

Cytotoxicity, measured as inhibition of cell growth of cultured cell lines, is a widely used method for testing the safety of biomaterials and chemicals. One major technical disadvantage with this method is the continuous routine maintenance of the cell lines. We decided to investigate the possibility of storing stock cultures of fibroblasts (L-929) in an ordinary refrigerator as a means of reducing the routine workload. Stock cultures of the mouse fibroblast cell line L-929 were prepared in plastic vials with Eagle's minimum essential medium. The vials were stored in a refrigerator at 4–10°C for periods of 7–31 days. The condition of the cells after storage was determined as cell viability, cell growth and the toxic response to acrylamide, measured as cell growth inhibition. We found that the L-929 cell line can be stored for 2–3, weeks with a viabilty > 90% and a cell growth of about 95%, compared to L-929 cells grown and subcultured in the normal manner. The results also show that the toxic response to acrylamide, using refrigerator stored L-929 cells, corresponds to that of control L-929 cells. We concluded that it is possible to store L-929 cells in a refrigerator for periods of up to 3 weeks and still use the cells for in vitro cytotoxic assays.

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Tissue type-specific expression of intermediate filament proteins in a cultured epithelial cell line from bovine mammary gland

The Journal of Cell Biology ◽

10.1083/jcb.96.1.37 ◽

1983 ◽

Vol 96 (1) ◽

pp. 37-50 ◽

Cited By ~ 93

Author(s):

E Schmid ◽

DL Schiller ◽

C Grund ◽

J Stadler ◽

WW Franke

Keyword(s):

Mammary Gland ◽

Epithelial Cell ◽

Cell Line ◽

Cell Lines ◽

Intermediate Filament ◽

Striking Difference ◽

Intermediate Filament Proteins ◽

Cell Clones ◽

Vimentin Filaments

Different clonal cell lines have been isolated from cultures of mammary gland epithelium of lactating cow's udder and have been grown in culture media containing high concentrations of hydrocortisone, insulin, and prolactin. These cell (BMGE+H), which grow in monolayers of typical epithelial appearance, are not tightly packed, but leave intercellular spaces spanned by desmosomal bridges. The cells contain extended arrays of cytokeratin fibrils, arranged in bundles attached to desmosomes. Gel electophoresis show that they synthesize cytokeratins similar, if not identical, to those found in bovine epidermis and udder, including two large (mol wt 58,500 and 59,000) and basic (pH range: 7-8) and two small (mol wt 45,500 and 50,000) and acidic (pH 5.32 and 5.36) components that also occur in phosphorylated forms. Two further cytokeratins of mol wts 44,000 (approximately pH 5.7) and 53,000 (pH 6.3) are detected as minor cytokeratins in some cell clones. BMGE+H cells do not produce vimentin filaments as determined by immunofluorescence microscopy and gel electrophoresis. By contrast, BMGE-H cells, which have emerged from the same original culture but have been grown without hormones added, are not only morphologically different, but also contain vimentin filaments and a different set of cytokeratins, the most striking difference being the absence of the two acidic cytokeratins of mol wt 50,000 and 45,500. Cells of the BMGE+H line are characterized by an unusual epithelial morphology and represent the first example of a nonmalignant permanent cell line in vitro that produces cytokeratin but not vimentin filaments. The results show that (a) tissue-specific patterns of intermediate filament expression can be maintained in permanent epithelial cell lines in culture, at least under certain growth conditions; (b) loss of expression of relatively large, basic cytokeratins is not an inevitable consequence of growth of epithelial cells in vitro. Our results further show that, during culturing, different cell clones with different cytoskeletal composition can emerge from the same cell population and suggest that the presence of certain hormones may have an influence on the expression of intermediate filament proteins.

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Synthesis and Experimental Validation of New Designed Heterocyclic Compounds with Antiproliferative Activity versus Breast Cancer Cell Lines MCF-7 and MDA-MB-231

Journal of Chemistry ◽

10.1155/2017/9729284 ◽

2017 ◽

Vol 2017 ◽

pp. 1-10 ◽

Cited By ~ 2

Author(s):

Vincenza Barresi ◽

Carmela Bonaccorso ◽

Domenico A. Cristaldi ◽

Maria N. Modica ◽

Nicolò Musso ◽

...

Keyword(s):

Cell Line ◽

Cell Lines ◽

Cancer Cell ◽

Anticancer Agents ◽

Cancer Cell Line ◽

Breast Cancer Cell Lines ◽

Design And Synthesis ◽

Human Breast Cell ◽

Mcf 7

Recent drug discovery efforts are highly focused towards identification, design, and synthesis of small molecules as anticancer agents. With this aim, we recently designed and synthesized novel compounds with high efficacy and specificity for the treatment of breast tumors. Based on the obtained results, we constructed a Volsurf+ (VS+) model using a dataset of 59 compounds able to predict the in vitro antitumor activity against MCF-7 cancer cell line for new derivatives. In the present paper, in order to further verify the robustness of this model, we report the results of the projection of more than 150 known molecules and 9 newly synthesized compounds. We predict their activity versus MCF-7 cell line and experimentally verify the in silico results for some promising chosen molecules in two human breast cell lines, MCF-7 and MDA-MB-231.

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The extracellular matrix of hybrids between melanoma cells and normal fibroblasts

Journal of Cell Science ◽

10.1242/jcs.91.2.281 ◽

1988 ◽

Vol 91 (2) ◽

pp. 281-286

Author(s):

M.C. Copeman ◽

H. Harris

Keyword(s):

Extracellular Matrix ◽

Protease Activity ◽

Malignant Tumour ◽

Melanoma Cells ◽

Chromosome Loss ◽

Type I ◽

Chromosome 4 ◽

Hybrid Cells

It has been shown that when malignant tumour cells are fused with normal fibroblasts the suppression of malignancy in the hybrids is linked to their ability to produce a collagenous extracellular matrix in vivo. When, as a consequence of chromosome loss, segregants arise that reacquire malignancy, these do not produce any detectable matrix. In this paper we examine the main components of the extracellular matrix produced in vitro by hybrids between malignant mouse melanoma cells and normal mouse fibroblasts. Hybrids in which malignancy is suppressed synthesize about ten times as much type 1 procollagen as the malignant segregants derived from them; they also retain more fibronectin in the cell layer and release less protease activity into the medium. Malignant segregants more closely resemble the parental melanoma cells in producing fibronectin and mainly types IV and V procollagen. When hybrid cells in which malignancy is initially suppressed are grown continuously in vitro, the production of type I procollagen declines, and the production of type V procollagen and the release of protease activity into the medium increase. These changes, which are associated with the loss from the hybrid cells of both copies of the chromosome 4 derived from the parental fibroblast, predict the reacquisition of malignancy when the cells are inoculated into mice. It is possible that one gene or set of genes located on chromosome 4 determines both the execution of the fibroblast differentiation programme and the suppression of malignancy.

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