Role of SV40 Small t in Cell Lysis, Transformation, and Signaling

2003 ◽  
pp. 229-242
Author(s):  
Ximena Montano ◽  
Kathy Rundell
Keyword(s):  
Cell Lysis ◽  
Sv40 Small T

ICAM-1-CD18 interaction mediates neutrophil cytotoxicity through protease release

1998 ◽  
Vol 274 (6) ◽  
pp. C1634-C1644 ◽  
Author(s):  
Carlton C. Barnett ◽  
Ernest E. Moore ◽  
Gary W. Mierau ◽  
David A. Partrick ◽  
Walter L. Biffl ◽  
...  
Keyword(s):  
Cho Cells ◽  
Chinese Hamster ◽  
Cell Lysis ◽  
Polymorphonuclear Neutrophil ◽  
Intercellular Adhesion Molecule ◽  
Wild Type ◽  
Myristate Acetate ◽  
Intercellular Adhesion Molecule 1 ◽  
Eglin C

Interaction of the β2-integrin complex on the polymorphonuclear neutrophil (PMN) with intercellular adhesion molecule-1 (ICAM-1) has been implicated in PMN-mediated cytotoxicity. This study examined interaction of the CD11a, CD11b, and CD18 subunits of the β2-integrin with ICAM-1, transfected into Chinese hamster ovarian (CHO) cells to avoid effects of other adhesion molecules. Incubation of quiescent PMNs with wild-type and ICAM-1-transfected CHO cells produced nominal cell lysis. Similarly, when phorbol myristate acetate (PMA)-activated PMNs were incubated with wild-type CHO cells, minimal cytotoxicity was produced. However, when ICAM-1-transfected CHO cells were incubated with PMA-activated PMNs, 40% cell lysis occurred. Blockade with a monoclonal antibody (MAb) to ICAM-1 or MAbs to CD11a, CD11b, or CD18 reduced PMN-mediated cytotoxicity to baseline. To examine the role of adhesion in cytotoxicity, we studied β2-integrin-mediated PMN adhesion to ICAM-1-transfected CHO cells and found that MAbs for CD11a, CD11b, and CD18 all abrogated PMN cytotoxicity despite disparate effects on adhesion. To assess the role of CD18, β2-integrin subunits were cross-linked, and CD18 alone mediated protease release. Moreover, ICAM-1 was immunoprecipitated from transfected CHO cells and incubated with PMNs. This soluble ICAM-1 provoked elastase release, similar to PMA, which could be inhibited by MAbs to CD18 but not MAbs to other β2-integrin subunits. In addition, coincubation with protease inhibitors eglin C and AAPVCK reduced PMN-mediated cytotoxicity to control levels. Finally, ICAM-1-transfected CHO cells were exposed to activated PMNs from a patient with chronic granulomatous disease that caused significant cell lysis, equivalent to that of PMNs from normal donors. Collectively, these data suggest that ICAM-1 provokes PMN-mediated cytotoxicity via CD18-mediated protease release.

pHe, [Ca2+]e, and cell death during metabolic inhibition: role of phospholipase A2 and sarcolemmal phospholipids

1998 ◽  
Vol 274 (1) ◽  
pp. H18-H26 ◽  
Author(s):  
Jan A. Post ◽  
Sheng-Yong Wang ◽  
Glenn A. Langer
Keyword(s):  
Cell Death ◽  
Arachidonic Acid ◽  
Lactate Dehydrogenase ◽  
Present Model ◽  
Cell Lysis ◽  
Metabolic Inhibition ◽  
Ldh Release ◽  
External Ph ◽  
Sarcolemmal Integrity

This study measures cellular lactate dehydrogenase (LDH) release during metabolic inhibition as a monitor of sarcolemmal integrity as affected by variation of external pH (pHe) and Ca2+ concentration ([Ca2+]e). The sigmoidal relationship between pHe and LDH release and pHe and net Ca2+ uptake was essentially identical with the 50% maximal value occurring at pH 7.0 for both. This suggests that a process(es) sensitive to both pHe and [Ca2+]eplays a role in cell lysis during the course of metabolic inhibition. Variation of pHe during metabolic inhibition did not alter the decline in cellular ATP, nor did it affect changes in sarcolemmal phospholipid topology. Intracellular pH followed changes of pHe with a few minutes lag. Cell lysis increased in a graded manner as pHe and [Ca2+]ewere increased, but pHe was the sole determinant of lysis, i.e., [Ca2+]elevel had no effect, at the lowest (6.2) and the highest (8.0) pHe levels. pHe variation did not affect the release of radiolabeled arachidonic acid, nor did inhibitors of phospholipase A2(PLA2) affect cell lysis at varying pHe. Therefore, cellular PLA2 activation could not be implicated for a role in cell lysis in the present model of metabolic inhibition. Alternatively, we propose that Ca2+ binding to the cytoplasmic leaflet, in combination with membrane alterations secondary to the metabolic insult, combine to destabilize the sarcolemma (20). This Ca2+ binding to the negatively charged phosphatidylserine results in the expression of the bilayer destabilizing effect of phosphatidylethanolamine. This Ca2+ binding is greatly diminished by lowered pH, resulting in an attenuation of cell lysis.

scholarly journals The role of cell lysis and matrix deposition in tumor growth modeling

2015 ◽  
Vol 2 (1) ◽  
Author(s):  
R Santagiuliana ◽  
C Stigliano ◽  
P Mascheroni ◽  
M Ferrari ◽  
P Decuzzi ◽  
...  
Keyword(s):  
Tumor Growth ◽  
Growth Modeling ◽  
Cell Lysis ◽  
Matrix Deposition ◽  
Tumor Growth Modeling

scholarly journals Using Mathematical Modelling to Explore Hypotheses about the Role of Bovine Epithelium Structure in Foot-And-Mouth Disease Virus-Induced Cell Lysis

PLoS ONE ◽  
2015 ◽  
Vol 10 (10) ◽  
pp. e0138571 ◽  
Author(s):  
Kyriaki Giorgakoudi ◽  
Simon Gubbins ◽  
John Ward ◽  
Nicholas Juleff ◽  
Zhidong Zhang ◽  
...  
Keyword(s):  
Mathematical Modelling ◽  
Disease Virus ◽  
Foot And Mouth Disease ◽  
Cell Lysis ◽  
Mouth Disease ◽  
Mouth Disease Virus ◽  
Foot And Mouth

Effect of Cell Lysis (CLs) Products on Acidophilic Chemolithotrophic Microorganisms and the Role of Acidocella Species

2017 ◽  
Vol 34 (10) ◽  
pp. 916-922 ◽  
Author(s):  
A. Vardanyan ◽  
P. Achilleos ◽  
N. Kafa ◽  
M. Papadopoulou ◽  
N. Vardanyan ◽  
...  
Keyword(s):  
Cell Lysis

scholarly journals Overexpression of Crry protects mesangial cells from complement-mediated injury.

1997 ◽  
Vol 8 (2) ◽  
pp. 223-233
Author(s):  
M Nangaku ◽  
R J Quigg ◽  
S J Shankland ◽  
N Okada ◽  
R J Johnson ◽  
...  
Keyword(s):  
Mesangial Cells ◽  
Regulatory Protein ◽  
Cell Lysis ◽  
Immunocytochemical Staining ◽  
Complement Regulatory Protein ◽  
Transfected Cells ◽  
Immune Injury ◽  
Complete Resistance

Crry is a membrane-associated complement regulatory protein expressed on glomerular mesangial, endothelial, and epithelial cells, which reduces C3/C5 convertase activity. This study utilized an overexpression strategy to determine the functional significance of Crry in cultured rat mesangial cells. A Crry expression vector was constructed and was tagged with a c-myc epitope that allowed transfected Crry to be distinguished from the constitutively expressed protein. In stable clones, overexpressed Crry was clearly detected immunocytochemically both by anti-c-myc and anti-Crry antibody in a membrane localization. The overexpression of Crry was also confirmed by Western blotting and immunoprecipitation. To determine if overexpression of Crry by mesangial cells confers a protective effect from complement attack, complement-mediated cell lysis assays were performed. Crry-transfected mesangial cells demonstrated complete resistance to complement-mediated cell lysis, which was reversed by neutralization of Crry with both monoclonal antibody and F(ab')2 fragments of the antibody. This study also investigated the role of Crry in protecting cells from the effects of sublytic complement attack. Overexpressed Crry suppressed antibody/complement induced production of superoxide, one of the inflammatory mediators induced by sublytic complement attack. Immunocytochemical staining confirmed a reduction in C3 and C5b-9 deposition in Crry-transfected cells. These results demonstrate directly that transfected Crry functions as a potent protector of mesangial cells against complement-mediated injury. Crry may play an important role in modulating the glomerular response to immune injury in vivo.

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