Detection of 65 kD heat shock protein in cerebrospinal fluid of tuberculous meningitis patients

Background  

Diagnosis of tuberculous meningitis (TBM) is difficult. Rapid confirmatory diagnosis is essential to initiate required therapy. There are very few published reports about the diagnostic significance of 65 kD heat shock protein (hsp) in TBM patients, which is present in a wide range of Mycobacterium tuberculosis species and elicits a cellular and humoral immune response. In the present study we have conducted a prospective evaluation for the demonstration of 65 kD hsp antigen in cerebrospinal fluid (CSF) of TBM patients, by indirect ELISA method using monoclonal antibodies (mAb) against the 65 kD hsp antigen, for the diagnosis of TBM.     

Control of dinucleoside polyphosphates by the FHIT-homologous HNT2 gene, adenine biosynthesis and heat shock in Saccharomyces cerevisiae

Background  

The FHIT gene is lost early in the development of many tumors. Fhit possesses intrinsic ApppA hydrolase activity though ApppA cleavage is not required for tumor suppression. Because a mutant form of Fhit that is functional in tumor suppression and defective in catalysis binds ApppA well, it was hypothesized that Fhit-substrate complexes are the active, signaling form of Fhit. Which substrates are most important for Fhit signaling remain unknown.     

Localization of heat shock protein 20 in swine carotid artery

Background  

The gene expression pattern in tumor cells differs from that in corresponding normal cells. In order to identify differentially expressed genes in colorectal tumors and normal colorectal epithelium, a differential display experiment was used to compare RNA expression in normal and tumor tissue samples.     

Functional characterization of a small heat shock protein from <Emphasis Type="Italic">Mycobacterium leprae</Emphasis>

Background  

Small heat shock proteins are ubiquitous family of stress proteins, having a role in virulence and survival of the pathogen. M. leprae, the causative agent of leprosy is an uncultivable organism in defined media, hence the biology and function of proteins were examined by cloning M. leprae genes in heterologous hosts. The study on sHsp18 was carried out as the knowledge about the functions of this major immunodominant antigen of M. leprae is scanty.     

<Emphasis Type="Italic">Chlamydia trachomatis</Emphasis>responds to heat shock,penicillin induced persistence,and IFN-gamma persistence by altering levels of the extracytoplasmic stress response protease HtrA

Background  

Chlamydia trachomatis, an obligate intracellular human pathogen, is the most prevalent bacterial sexually transmitted infection worldwide and a leading cause of preventable blindness. HtrA is a virulence and stress response periplasmic serine protease and molecular chaperone found in many bacteria. Recombinant purified C. trachomatis HtrA has been previously shown to have both activities. This investigation examined the physiological role of Chlamydia trachomatis HtrA.     

Role of heat shock protein 47 in intestinal fibrosis of experimental colitis

Background and aims

Intestinal fibrosis is a clinically important issue of inflammatory bowel disease (IBD). It is unclear whether or not heat shock protein 47 (HSP47), a collagen-specific molecular chaperone, plays a critical role in intestinal fibrosis. The aim of this study is to investigate the role of HSP47 in intestinal fibrosis of murine colitis.

Methods

HSP47 expression and localization were evaluated in interleukin-10 knockout (IL-10KO) and wild-type (WT, C57BL/6) mice by immunohistochemistry. Expression of HSP47 and transforming growth factor-β1 (TGF-β1) in colonic tissue was measured. In vitro studies were conducted in NIH/3T3 cells and primary culture of myofibroblasts separated from colonic tissue of IL-10KO (PMF KO) and WT mice (PMF WT) with stimulation of several cytokines. We evaluated the inhibitory effect of administration of small interfering RNA (siRNA) targeting HSP47 on intestinal fibrosis in IL-10KO mice in vivo.

Results

Immunohistochemistry revealed HSP47 positive cells were observed in the mesenchymal and submucosal area of both WT and IL-10 KO mice. Gene expressions of HSP47 and TGF-β1 were significantly higher in IL-10KO mice than in WT mice and correlated with the severity of inflammation. In vitro experiments with NIH3T3 cells, TGF-β1 only induced HSP47 gene expression. There was a significant difference of HSP47 gene expression between PMF KO and PMF WT. Administration of siRNA targeting HSP47 remarkably reduced collagen deposition in colonic tissue of IL-10KO mice.

Conclusions

Our results indicate that HSP47 plays an essential role in intestinal fibrosis of IL-10KO mice, and may be a potential target for intestinal fibrosis associated with IBD.     

Increased expression of heat shock protein 105 in rat uterus of early pregnancy and its significance in embryo implantation

Background  

Heat shock proteins (Hsps) are a set of highly conserved proteins, Hsp105, has been suggested to play a role in reproduction.     

Absence of force suppression in rabbit bladder correlates with low expression of heat shock protein 20

Background  

Nitroglycerin can induce relaxation of swine carotid artery without sustained reductions in [Ca²⁺]_i or myosin regulatory light chain (MRLC) phosphorylation. This has been termed force suppression and been found to correlate with ser¹⁶-phosphorylation of heat shock protein 20 (HSP20). We tested for the existence of this mechanism in a smooth muscle that is not responsive to nitric oxide.     

Inducible and constitutive heat shock gene expression responds to modification of Hsp70 copy number in Drosophila melanogaster but does not compensate for loss of thermotolerance in Hsp70 null flies

Background  

The heat shock protein Hsp70 promotes inducible thermotolerance in nearly every organism examined to date. Hsp70 interacts with a network of other stress-response proteins, and dissecting the relative roles of these interactions in causing thermotolerance remains difficult. Here we examine the effect of Hsp70 gene copy number modification on thermotolerance and the expression of multiple stress-response genes in Drosophila melanogaster, to determine which genes may represent mechanisms of stress tolerance independent of Hsp70.     

Proteomic analysis of acidic chaperones, and stress proteins in extreme halophile Halobacterium NRC-1: a comparative proteomic approach to study heat shock response

Background  

Halobacterium sp. NRC-1 is an extremely halophilic archaeon and has adapted to optimal growth under conditions of extremely high salinity. Its proteome is highly acidic with a median pI of 4.9, a unique characteristic which helps the organism to adapt high saline environment. In the natural growth environment, Halobacterium NRC-1 encounters a number of stressful conditions including high temperature and intense solar radiation, oxidative and cold stress. Heat shock proteins and chaperones play indispensable roles in an organism's survival under many stress conditions. The aim of this study was to develop an improved method of 2-D gel electrophoresis with enhanced resolution of the acidic proteome, and to identify proteins with diverse cellular functions using in-gel digestion and LC-MS/MS and MALDI-TOF approach.     

Downregulation of heat shock protein 70 protects rheumatoid arthritis fibroblast-like synoviocytes from nitric oxide-induced apoptosis

Introduction  

Heat shock protein 70 (Hsp70) is a well-known anti-apoptotic protein that blocks multiple steps in the stress-induced apoptotic pathway. Enhanced Hsp70 expression has previously been demonstrated in rheumatoid arthritis (RA) fibroblast-like synoviocytes (FLSs). The authors investigated the role of Hsp70 in the survival of RA FLSs in a sodium nitroprusside (SNP)-treated environment.     

Regulation of tight junction assembly and epithelial morphogenesis by the heat shock protein Apg-2

Background  

Tight junctions are required for epithelial barrier formation and participate in the regulation of signalling mechanisms that control proliferation and differentiation. ZO-1 is a tight junction-associated adaptor protein that regulates gene expression, junction assembly and epithelial morphogenesis. We have previously demonstrated that the heat shock protein Apg-2 binds ZO-1 and thereby regulates its role in cell proliferation. Here, we addressed the question whether Apg-2 is also important for junction formation and epithelial morphogenesis.     

Investigating the role of small, acid-soluble spore proteins (SASPs) in the resistance of Clostridium perfringens spores to heat

Background  

Clostridium perfringens type A food poisoning is caused by enterotoxigenic C. perfringens type A isolates that typically possess high spore heat-resistance. The molecular basis for C. perfringens spore heat-resistance remains unknown. In the current study, we investigated the role of small, acid-soluble spore proteins (SASPs) in heat-resistance of spores produced by C. perfringens food poisoning isolates.     

Interleukin-6 and procalcitonin in children with sepsis and septic shock

Objectives. To examine the behavior of interleukin-6 (IL-6) and procalcitonin (PCT) and verify whether they can be used to differentiate children with septic conditions. Methods. Septic children aged between 28 days and 14 years, prospectively enrolled from 01/2004 to 12/2005, were divided into sepsis (SG; n = 47) and septic shock (SSG; n = 43) groups. IL-6 and PCT were measured at admission (T0) and 12 h later (T12h). PCT results were classed as: 0.5 ng/mL = sepsis unlikely; 0.5 to <2 = sepsis possible; 2 to <10 = systemic inflammation; 10 = septic shock. Results. Ninety children were included. At T0, there was a higher frequency of SSG with higher PCT compared with SG [SSG: 30 (69.7%) > SG: 14 (29.8%); p < 0.05]. Similar results were observed at T12h. PRISM was significantly higher for SSG patients with higher PCT than SG patients. At T0, IL-6 levels were higher in SSG [SSG: 213.10 (10.85–396.70) > SG: 63.21 (0.86–409.82); p = 0.001], but not statistically different at T12h. IL-6 levels positively correlated with PRISM score in SSG patients at admission (p = 0.001; r = 0.86). Conclusion. PCT and IL-6 appear to be helpful in early assessment of pediatric sepsis, are of diagnostic value at admission, and are related to disease severity.     

Over-expression of a small heat shock protein,sHSP17.7, confers both heat tolerance and UV-B resistance to rice plants

Exposure of rice (Oryza sativa L.) seedlings to a high temperature (42°C) for 24 h resulted in a significant increase in resistance to UV-B damage. UV-B resistance was enhanced in parallel with the period of heat treatment. sHSP17.7 was isolated from heated rice seedlings, and the influence of rice sHSP17.7 expression on the viability of E. coli under heat-shock conditions was assessed. After heating, the survival rate of sHSP17.7 cells was 2-fold higher than that of the control cells. The molecular chaperone activity of sHSP17.7 was investigated using catalase as a substrate. Recombinant sHSP17.7 had heat-stable chaperone properties that were capable of protecting stressed catalase from precipitation. sHSP17.7 was overexpressed in the rice cultivar Hoshinoyume, by Agrobacterium-mediated transformation, under the control of a CaMV 35S promoter. Transgenic rice plants with increased levels of sHSP17.7 protein exhibited significantly increased thermotolerance compared to untransformed control plants. The level of increased thermotolerance was correlated with the level of increased sHSP17.7 protein in the transgenic plants. The transgenic rice plant with the highest constitutive expression of sHSP17.7 had significantly greater resistance to UV-B stress than untransformed control plants. Increase in the degree of resistance of transgenic plants to UV-B was accompanied by an increase in production of sHSP17.7 protein.     

Variation in basal heat shock protein 70 is correlated to core temperature in human subjects

Heat shock proteins are highly conserved proteins and play an important chaperone role in aiding the folding of nascent proteins within cells. The heat shock protein response to various stressors, both in vitro and in vivo, is well characterised. However, basal levels of heat shock protein 70 (Hsp70) have not previously been investigated. Monocyte-expressed Hsp70 was determined every 4 h, over a 24 h time period, in 17 healthy male subjects (177 ± 6.4 cm, 75.7 ± 10.9 kg, 19.8 ± 4.3 years) within a temperature and activity controlled environment. Core temperature was measured at 5-min intervals during the 24 h period. Hsp70 showed significant diurnal variation (F = 7.4; p < 0.001), demonstrating peaks at 0900 and 2100 hours, and a nadir at 05.00. Core temperature followed a similar temporal trend (range = 35.96–38.10°C) and was significantly correlated with Hsp70 expression (r _s = 0.44; p < 0.001). These findings suggest a high responsiveness of Hsp70 expression in monocytes to slight variations in core temperature.     

Temporal variation in constitutive and inducible heat shock proteins in the Zebra Finch Taeniopygia guttata

Cellular stressors initiate the heat shock response mediated by heat shock proteins (HSPs). There are two main types of HSPs, constitutive (always expressed) and inducible (upon stress), but as many in vivo studies fail to distinguish between them and because temporal expression patterns often differ among various types of HSPs, it is unclear when to measure HSPs. In this study, 26 (13 per treatment) adult female Zebra Finches Taeniopygia guttata were heat‐stressed (39 °C) or placed in a control brooder (room temperature) for 3 h and were bled 1 week prior to and at 1, 2, 4, 6 and 20 h post‐treatment. Treatment had no effect on levels of either constitutive HSP70 or inducible HSP90, but both HSPs decreased with time relative to baseline, suggesting a possible effect of handling stress and/or circadian variation.