Enhanced Levels of Staphylococcus aureus Stress Protein GroEL and DnaK Homologs Early in Infection of Human Epithelial Cells

ABSTRACT Antibodies to Staphylococcus aureus heat shock proteins (Hsps) are present in the sera of patients with S. aureus endocarditis (M. W. Qoronfleh, W. Weraarchakul, and B. J. Wilkinson, Infect. Immun. 61:1567–1570, 1993). Although these proteins are immunogenic, their role in infection has not been established. We developed a cell culture system as a model to examine the potential involvement of staphylococcal Hsps in the initial events of infection. This study supports a model in which a clinical endocarditis isolate responds to host cell signals by selectively regulating the synthesis of numerous proteins, including the stress proteins Hsp60 (GroEL homolog) and Hsp70 (DnaK homolog) and a unique 58-kDa protein.

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Extracellular cell stress (heat shock) proteins—immune responses and disease: an overview

Philosophical Transactions of the Royal Society B Biological Sciences ◽

10.1098/rstb.2016.0522 ◽

2017 ◽

Vol 373 (1738) ◽

pp. 20160522 ◽

Cited By ~ 49

Author(s):

A. Graham Pockley ◽

Brian Henderson

Keyword(s):

Heat Shock ◽

Heat Shock Proteins ◽

Stress Proteins ◽

Biological Fluids ◽

Stress Protein ◽

Cell Stress ◽

Immune Reactivity ◽

Protein Levels ◽

Shock Proteins ◽

Adaptive Immune Systems

Extracellular cell stress proteins are highly conserved phylogenetically and have been shown to act as powerful signalling agonists and receptors for selected ligands in several different settings. They also act as immunostimulatory ‘danger signals’ for the innate and adaptive immune systems. Other studies have shown that cell stress proteins and the induction of immune reactivity to self-cell stress proteins can attenuate disease processes. Some proteins (e.g. Hsp60, Hsp70, gp96) exhibit both inflammatory and anti-inflammatory properties, depending on the context in which they encounter responding immune cells. The burgeoning literature reporting the presence of stress proteins in a range of biological fluids in healthy individuals/non-diseased settings, the association of extracellular stress protein levels with a plethora of clinical and pathological conditions and the selective expression of a membrane form of Hsp70 on cancer cells now supports the concept that extracellular cell stress proteins are involved in maintaining/regulating organismal homeostasis and in disease processes and phenotype. Cell stress proteins, therefore, form a biologically complex extracellular cell stress protein network having diverse biological, homeostatic and immunomodulatory properties, the understanding of which offers exciting opportunities for delivering novel approaches to predict, identify, diagnose, manage and treat disease. This article is part of the theme issue ‘Heat shock proteins as modulators and therapeutic targets of chronic disease: an integrated perspective’.

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Stress protein systems of mammalian cells

AJP Cell Physiology ◽

10.1152/ajpcell.1986.250.1.c1 ◽

1986 ◽

Vol 250 (1) ◽

pp. C1-C17 ◽

Cited By ~ 426

Author(s):

J. R. Subjeck ◽

T. T. Shyy

Keyword(s):

Heat Shock ◽

Heat Shock Proteins ◽

Mammalian Cells ◽

Stress Proteins ◽

Heat Exposure ◽

Stress Protein ◽

Protective Role ◽

Living Organisms ◽

Shock Proteins ◽

Glucose Regulated Proteins

Living organisms are known to react to a heat stress by the selective induction in the synthesis of several polypeptides. In this review we list the major stress proteins of mammalian cells that are induced by heat shock and other environments and categorize these proteins into specific subgroups: the major heat shock proteins, the glucose-regulated proteins, and the low-molecular-weight heat shock proteins. Characteristics of the localization and expression of proteins in each of these subgroups are presented. Specifically, the nuclear/nucleolar locale of certain of the major heat shock proteins is considered with respect to their association with RNA and the recovery of cells after a heat exposure. The induction of these major heat shock proteins and the repression of the glucose-regulated proteins as a result of reoxygenation of anoxic cells or by the addition of glucose to glucose-deprived cultures is described. Changes in the expression of these protein systems during embryogenesis and differentiation in mammalian and nonmammalian systems is summarized, and the protective role that some of these proteins appear to play in protecting the animal against the lethal effects of a severe heat treatment and against teratogenesis is critically examined.

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A Cell Culture System for Study of the Development of Toxoplasma gondii Bradyzoites

Journal of Eukaryotic Microbiology ◽

10.1111/j.1550-7408.1995.tb01556.x ◽

1995 ◽

Vol 42 (2) ◽

pp. 150-157 ◽

Cited By ~ 106

Author(s):

LOUIS M. WEISS ◽

DENISE LAPLACE ◽

PETER M. TAKVORIAN ◽

HERBERT B. TANOWITZ ◽

ANN CALI ◽

...

Keyword(s):

Cell Culture ◽

Toxoplasma Gondii ◽

Culture System ◽

Cell Culture System ◽

A Cell

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Interaction between heat shock factor and hsp70 is insufficient to suppress induction of DNA-binding activity in vivo

Molecular and Cellular Biology ◽

10.1128/mcb.14.10.6552-6560.1994 ◽

1994 ◽

Vol 14 (10) ◽

pp. 6552-6560

Author(s):

S K Rabindran ◽

J Wisniewski ◽

L Li ◽

G C Li ◽

C Wu

Keyword(s):

Heat Shock ◽

Dna Binding ◽

Heat Shock Proteins ◽

Expression System ◽

Stress Protein ◽

Binding Activity ◽

Protein Family ◽

Oligomeric State ◽

Dna Binding Activity ◽

Shock Proteins

The intracellular level of free heat shock proteins, in particular the 70-kDa stress protein family, has been suggested to be the basis of an autoregulatory mechanism by which the cell measures the level of thermal stress and regulates the synthesis of heat shock proteins. It has been proposed that the DNA-binding and oligomeric state of the heat shock transcription factor (HSF) is a principal step in the induction pathway that is responsive to the level of 70-kDa stress protein. To test this hypothesis, we investigated the association between HSF and 70-kDa stress protein by means of a coimmunoprecipitation assay. We found that 70-kDa stress proteins associate to similar extents with both latent and active forms of HSF, although unlike other 70-kDa stress protein substrates, the association with HSF was not significantly disrupted in the presence of ATP. Gel mobility shift assays indicated that active HSF trimers purified from a bacterial expression system could not be substantially deactivated in vitro with purified 70-kDa stress protein and ATP. In addition, elevated concentrations of hsp70 alone could not significantly inhibit induction of the DNA-binding activity of endogenous HSF in cultured rat cells, and the induction was also not inhibited in cultured rat cells or Drosophila cells containing elevated levels of all members of the heat shock protein family. However, the deactivation of HSF to the non-DNA-binding state after prolonged heat stress or during recovery could be accelerated by increased levels of heat shock proteins. Hence, the level of heat shock proteins may affect the rate of disassembly of HSF trimers, but another mechanism, as yet undefined, appears to control the onset of the oligomeric transitions.

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