Death mechanisms of animal cells in conditions of intensive agitation

Al‐Rubeai, Mohamed; Singh, R. P.; Goldman, M.; Emery, A. N.

doi:10.1002/bit.260450602

Cited by 143 publications

(97 citation statements)

References 24 publications

(4 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…These results may be in contrast to those of Al-Rubei et al (1990, 1995, who show alterations in both metabolism and apoptosis. However, their results were obtained using murine hybridoma cells subjected to much higher rates of agitation (600 and 1500 rpm).…”

Section: Discussioncontrasting

confidence: 84%

“…Often, increases in oxygen mass transfer are achieved by increasing agitation speed and the use of sparging. It is known that hydrodynamic forces arising from these conditions can have a number of effects on mammalian cells (Papoutsakis, 1991a) including effects on cell growth (Al-Rubeai et al, 1990;Lakhotia et al, 1993), cell viability (Al-Rubeai et al, 1995), cell metabolism (Al-Rubeai et al, 1990), and the expression of cell surface receptor molecules (Al-Rubeai et al, 1993;Lakhotia et al, 1993;McDowell and Papoutsakis, 1998b).…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Culture of human T cells in stirred bioreactors for cellular immunotherapy applications: Shear, proliferation, and the IL-2 receptor

Carswell

Papoutsakis

2000

Biotechnol. Bioeng.

View full text Add to dashboard Cite

Section: Discussioncontrasting

confidence: 84%

Section: Introductionmentioning

confidence: 99%

Culture of human T cells in stirred bioreactors for cellular immunotherapy applications: Shear, proliferation, and the IL-2 receptor

Carswell

Papoutsakis

2000

Biotechnol. Bioeng.

View full text Add to dashboard Cite

“…Loss of cell viability due to shear stress by lowlevel shear stress (320 W m −3 ) has also been examined. Murine hybridoma cells were subjected to sublytic forces and were observed to cause cellular damage within the cell, which, over time, caused the induction of the apoptotic pathway and ultimately cell death (Al-Rubeai et al, 1995a).…”

Section: Introductionmentioning

confidence: 99%

Effect of shear stress on expression of a recombinant protein by Chinese hamster ovary cells

Keane

Ryan

Gray

2002

Biotech & Bioengineering

View full text Add to dashboard Cite

A flow chamber was used to impart a steady laminar shear stress on a recombinant Chinese hamster ovary (CHO) cell line expressing human growth hormone (hGH). The cells were subjected to shear stress ranging from 0.005 to 0.80 N m(-2). The effect of shear stress on the cell specific glucose uptake, cell specific hGH, and lactate productivity rates were calculated. No morphological changes to the cells were observed over the range of shear stresses examined. When the cells were subjected to 0.10 N m(-2) shear in protein-free media without Pluronic F-68, recombinant protein production ceased with no change in cell morphology, whereas control cultures were expressing hGH at 0.35 microg/10(6 )cells/h. Upon addition of the shear protectants, Pluronic F-68 (0.2% [w/v]) or fetal bovine serum (1.0% [v/v] FBS), the productivity of the cells was restored. The effect of increasing shear stress on the cells in protein-free medium containing Pluronic F-68 was also investigated. Cell specific metabolic rates were calculated for cells under shear stress and for no-shear control cultures performed in parallel, with shear stress rates expressed as a percentage of those obtained for control cultures. Upon increasing shear from 0.005 to 0.80 N m(-2), the cell specific hGH productivity decreased from 100% at 0.005 N m(-2) to 49% at 0.80 N m(-2) relative to the no-shear control. A concurrent increase in the glucose uptake rate from 115% at 0.01 N m(-2) to 142% at 0.80 N m(-2), and decreased lactate productivity from 92% to 50%, revealed a change in the yield of products from glucose compared with the static control. It was shown that shear stress, at sublytic levels in medium containing Pluronic F-68, could decrease hGH specific productivity.

show abstract

“…Within the bioreactor environment apoptosis can be triggered by a number of stimuli, including exhaustion of essential nutrients (amino acids, serum components, and glucose), accumulation of metabolic by-products, and alterations in pH, dissolved oxygen content and medium osmolarity (Singh et al 1994;Simpson et al 1998;Al-Rubeai 1999, 2002). Additional environmental factors that lead to apoptotic cell death in large-scale mammalian cell cultures include those caused by mechanical stresses (Al-Rubeai et al 1995).…”

Section: Introductionmentioning

confidence: 99%

Apoptosis and Its Suppression in Hepatocytes Culture

Mukwena

Al‐Rubeai

2004

Cytotechnology

View full text Add to dashboard Cite

In order to achieve the goal of developing extracorporeal liver support devices, it is necessary to optimise bioprocess environment such that viability and function are maximised. Optimising culture medium composition and controlling the constitution of the cellular microenvironment within the bioreactor have for many years been considered vital to achieving these aims. Coupled to this is the need to understand apoptosis, the prime suspect in the demise of animal cultures, including those of hepatocytes. Results presented here show that absent nutrients including glucose and amino acids play a substantial part in the induction of apoptosis. The use of chemical apoptosis inhibitors was utilised to investigate key components of hepatic apoptosis where caspases, predominantly caspase 8, were implicated in staurosporine (STS)-induced HepZ apoptosis. Caspase 9 and 3 activation although recorded was of less significance. Interestingly, these results were not consistent with those of mitochondrial membrane depolarisation where inhibition of caspase activation appeared to drive depolarisation. Inhibition of mitochondrial permeability transition and use of anti-oxidants was unsuccessful in reducing apoptosis, caspase activation and mitochondrial membrane depolarisation. In further studies, the anti-apoptotic gene bcl-2 was over-expressed in HepZ, resulting in a cell line that was more robust and resistant to death induced by glucose and cystine deprivation and treatment with STS. Bcl-2 did not however show significant cytoprotectivity where apoptosis was stimulated by deprivation of glutamine and serum. Overall, results indicated that although apoptosis can be curbed by use of chemical inhibitors and genetic manipulation, their success is dependent on apoptotic stimuli.

show abstract

Death mechanisms of animal cells in conditions of intensive agitation

Cited by 143 publications

References 24 publications

Culture of human T cells in stirred bioreactors for cellular immunotherapy applications: Shear, proliferation, and the IL-2 receptor

Culture of human T cells in stirred bioreactors for cellular immunotherapy applications: Shear, proliferation, and the IL-2 receptor

Effect of shear stress on expression of a recombinant protein by Chinese hamster ovary cells

Apoptosis and Its Suppression in Hepatocytes Culture

Contact Info

Product

Resources

About