Expression of the 60 kDa and 71 kDa heat shock proteins and presence of antibodies against the 71 kDa heat shock protein in pediatric patients with immune thrombocytopenic purpura

Heat shock proteins and kidney disease: perspectives of HSP therapy

Heat shock proteins (HSPs) mediate a diverse range of cellular functions, prominently including folding and regulatory processes of cellular repair. A major property of these remarkable proteins, dependent on intracellular or extracellular location, is their capacity for immunoregulation that optimizes immune activity while avoiding hyperactivated inflammation. In this review, recent investigations are described, which examine roles of HSPs in protection of kidney tissue from various traumatic influences and demonstrate their potential for clinical management of nephritic disease. The HSP70 class is particularly attractive in this respect due to its multiple protective effects. The review also summarizes current understanding of HSP bioactivity in the pathophysiology of various kidney diseases, including acute kidney injury, diabetic nephropathy, chronic glomerulonephritis, and lupus nephritis-along with other promising strategies for their remediation, such as DNA vaccination.

Multiple sclerosis-linked and interferon-beta-regulated gene expression in plasmacytoid dendritic cells

The cause of multiple sclerosis (MS) is not known and the mechanism of interferon-beta, a disease-modifying treatment, is not well-understood. We studied gene expression in plasmacytoid dendritic cells (pDCs), antigen-presenting cells implicated in MS pathogenesis. PDCs were separated from healthy donors and MS patients at two time points: before and after initiation of treatment with interferon-beta. Expression of selected MS-linked and interferon-beta-regulated genes was validated with single assays. We have identified 60 genes which were abnormally expressed in MS patients and were corrected after treatment. These genes could be studied as potential MS biomarkers and possible therapeutic targets in MS.

Heat shock proteins in oncology: diagnostic biomarkers or therapeutic targets?

Heat shock proteins (HSP) are a family of proteins induced in cells exposed to different insults. This induction of HSPs allows cells to survive stress conditions. Mammalian HSPs have been classified into six families according to their molecular size: HSP100, HSP90, HSP70, HSP60, HSP40 and small HSPs (15 to 30kDa) including HSP27. These proteins act as molecular chaperones either helping in the refolding of misfolded proteins or assisting in their elimination if they become irreversibly damaged. In recent years, proteomic studies have characterized several different HSPs in various tumor types which may be putative clinical biomarkers or molecular targets for cancer therapy. This has led to the development of a series of molecules capable of inhibiting HSPs. Numerous studies speculated that over-expression of HSP is in part responsible for resistance to many anti-tumor agents and chemotherapeutics. Hence, from a pharmacological point of view, the co-administration of HSP inhibitors together with other anti-tumor agents is of major importance in overcoming therapeutic resistance. In this review, we provide an overview of the current status of HSPs in autoimmune, cardiovascular, and neurodegenerative diseases with special emphasis on cancer.

Reduced heat shock protein 70 in airway smooth muscle in patients with chronic obstructive pulmonary disease

Studies demonstrated that pathophysiological abnormalities of airway smooth muscle (ASM) contribute significantly to chronic obstructive pulmonary disease (COPD) pathogenesis, the aim of this study is to investigate heat shock protein 70 (Hsp70) in ASM in COPD. ASM from 8 COPD patients and 6 controls were isolated for detection of Hsp70 using Western blot. Male adult Wister rats were exposed to mixture of cigarette smoke/air or room air for an indicated period. The lung tissues were obtained for pathological analysis, and ASM were dissected for Hsp70 detection. Normalized Hsp70 in ASM from COPD patients was significantly lower than that from controls (P <.001), and it was a significant positive correlation of Hsp70 and lung function. One-month exposure of rats to cigarette smoke/air mixture led to increased expression of Hsp70 and heat shock transcription factor (Hsf1) in ASM as compared to controls, whereas 3-month exposure caused dramatically reduced Hsp70 and Hsf1 than control animals. In addition, 3-month exposure to cigarette smoke/air mixture resulted in significantly lower Hsp70 and Hsf1 in rats ASM than 1-month exposure (P <.001), and it was a positive correlation of Hsf1 and Hsp70. Long-term cigarette smoking results in reduced expression of Hsp70 in ASM. This finding provides additional insight in understanding molecular changes in ASM during COPD pathogenesis.

Heat shock protein expression is low in intestinal mucosa in juvenile idiopathic arthritis: a defect in immunoregulation?

OBJECTIVES

Heat shock proteins (HSPs) are involved in the regulation of inflammation and in the maintenance of mucosal integrity. Their altered expression may be a marker of mucosal inflammation and also contribute to tissue injury. The small intestinal mucosa in children with juvenile idiopathic arthritis (JIA) shows signs of intestinal immune activation, such as increased intraepithelial cytotoxic lymphocyte counts. To further evaluate the characteristics of this immune activation in JIA, we have studied the expression of several HSPs, major histocompatibility complex (MHC) class I-related chain A (MICA), and the heat shock transcription factor 1 (HSF1) in intestinal biopsies from children with JIA.

METHODS

We studied 15 patients with JIA. Controls included 13 children without JIA, studied for various gastrointestinal (GI) symptoms, but eventually shown not to have any GI disease. The subjects were examined by endoscopy. The expression of HSP60, HSP70, MICA, and HSF1 was analysed in ileal and duodenal biopsies by using immunohistochemistry.

RESULTS

The expression levels of HSP60, MICA, and HSF1 were significantly lower in the duodenal epithelium in the JIA patients compared to the controls. MICA and HSF1 also showed lower expression in the ileal epithelium. The expression of HSP70 did not differ between the groups.

CONCLUSIONS

The downregulation of HSP60, MICA, and HSF1 in small intestinal mucosa may indicate that intestinal epithelial cells show immune aberration in JIA. We speculate that the low heat shock response may play a role in the pathogenesis of JIA, interfering with mucosal integrity and local intestinal immunoregulation.

Frequency of anti-hsp60, -65 and -70 antibodies in sera of patients with juvenile idiopathic arthritis

Cross-reactivity between microbial and human heat shock proteins (hsps) led to the concept that hsp might be involved in the etiopathogenesis of autoimmune diseases. We investigated antibodies to recombinant human hsp60, recombinant Mycobacterium bovis hsp65 and to stress-inducible recombinant human hsp70 using enzyme-linked immunosorbent assay (ELISA) in sera of 209 juvenile idiopathic arthritis (JIA) patients and 50 healthy controls. Anti-hsp60 antibodies did not exceed the control level in any JIA patient. The numbers of JIA patients (16/209, 7.6%) who raised anti-hsp65 antibodies was equal to healthy controls (4/50, 8%). Elevated levels of antibodies against hsp70 were found in a cohort of patients with JIA (36.8%) when compared with age-matched healthy individuals (2%). These antibodies were predominantly of IgG isotype in systemic disease and IgM isotype in oligoarthritis. In polyarthritis both IgG and IgM antibodies frequently occurred. Significantly higher anti-hsp70 antibody levels were found in RF-positive JIA patients. The levels of anti-hsp70 antibodies correlated with the severity of disease evaluated on the basis of Steinbrocker's functional classification and rtg staging system. No association between anti-hsp70 antibody levels and ANA, HLA B27 and disease duration (less than 2 years x more than 2 years) was observed except IgM anti-hsp70 antibody where significantly higher levels were also detected in HLA B27-positive patients. The prevalence of anti-hsp70 antibodies is much higher in JIA patients when compared with healthy controls, suggesting their possible role in pathological mechanism of the disease.

Plasma antibodies to heat shock protein 60 and heat shock protein 70 are associated with increased risk of electrocardiograph abnormalities in automobile workers exposed to noise

In the living and working environment, stressful factors, such as noise, can cause health problems including cardiovascular diseases and noise-induced hearing loss. Some heat shock proteins (Hsps) play an important role in protecting cardiac cells against ischemic injury, and antibodies against these Hsps are associated with the development and prognosis of atherogenesis, coronary heart disease, and hypertension. Whether the presence of such antibodies is associated with abnormal electrocardiography (ECG) in stressed autoworkers exposed to chronic noise is presently unknown. Therefore, we investigated the association between the levels of plasma anti-Hsp60 and anti-Hsp70 with electrocardiograph abnormality in 396 autoworkers exposed to different noise levels by using Western blot, ECG, and multivariate logistic regression analysis. The results showed that the increase in levels of anti-Hsp70 was associated with a higher risk of ECG abnormalities characteristic of chronic myocardial ischemia (P < 0.05), conductive abnormality (P < 0.01), or heart displacement (P < 0.05); in contrast, elevated anti-Hsp60 was related to ECG abnormalities characteristic of sinus arrhythmia, chronic myocardial ischemia, and ectopic rhythm (P < 0.01 for all). Overall, high levels of both anti-Hsp70 and anti-Hsp60 were associated with significantly increased risk of ECG abnormalities (odds ratio [OR] = 1.73 and 95% confidence interval [Cl] = 1.04-2.86 for anti-Hsp70 and OR = 1.36 and 95% Cl = 1.07-1.72 for anti-Hsp60) with and without adjustment for cumulative noise exposure (OR = 1.96 and 95% Cl = 1.20-3.21 for anti-Hsp70 and OR = 3.93 and 95% Cl = 1.72-8.92 for anti-Hsp60). These findings suggest that the production of both anti-Hsp70 and anti-Hsp60 may be independent risk factors for the development and progression of abnormal ECG and therefore possibly cardiovascular diseases in autoworkers exposed to occupational noise.

Antibodies against heat shock proteins in environmental stresses and diseases: friend or foe?

Heat shock proteins (Hsps) can be found in two forms, intracellular and extracellular. The intracellular Hsps are induced as a result of stress and have been found to be cytoprotective in many instances due to their chaperone functions in protein folding and in protein degradation. The origin and role of extracellular Hsps is less clear. Although they were suspected originally to be released from damaged cells (necrosis), their presence in most normal individuals rather suggests that they have regulatory functions in circulation. As immunodominant molecules, Hsps can stimulate the immune system, leading to the production of autoantibodies recognizing epitopes shared by microbial and human Hsps. Thus, extracellular Hsps can influence the inflammatory response as evidenced by the production of inflammatory cytokines. Antibodies to Hsps have been found under normal conditions but seem to be increased in certain stresses and diseases. Such antibodies could regulate the inflammatory response positively or negatively. Here, we review the literature on the findings of antibodies to Hsps in situations of environmental or occupational stress and in a number of diseases and discuss their possible significance for the diagnosis, prognosis, or pathogenesis of these diseases.

An efficient proteomics-based approach for the screening of autoantibodies

This study presents an improved method for the complete transfer of proteins separated by two-dimensional gel electrophoresis to a membrane, specifically designed for the screening and identification of antigens recognized by autoantibodies in patients with breast cancer (BCP) and healthy volunteers. This paper reports the evaluation of this technique using proteins from MCF7 as a source of antigens following 2-DE separation. The appropriate quantity of protein to be loaded on gels (150 microg) has been determined, the aim being a complete and reproducible recovery of all separated proteins onto the polyvinylidene fluoride membrane (2D-blot) after a semi-dry electrotransfer. Several different transfer methods were tested in parallel, resulting in the selection and optimisation of one using a discontinuous buffer system, based on the isotachophoresis theory. To facilitate the comparative analysis of the different sets of 2D-blots probed with individual sera from BCP and healthy volunteers, the 2D-blots were stained with colloidal gold following the immunodetection step. The gels and 2D-blots were scanned and analysed by imaging software. The matching permitted exact localisation of particular relevant protein spots hybridised by antibodies on the 2D-blots. These spots were subsequently located on preparative gels for identification by mass spectrometry. A set of 40 2D-blots was probed with 20 sera from patients with breast cancer and 20 sera from healthy volunteers. In the protein profiles submitted to immunodetection, 15 proteins were repeatedly immunodetected by both BCP and sera from healthy people. Those proteins were identified by mass spectrometry. Conversely, some protein isoforms were preferentially immunodetected by BCP sera and may reflect the presence of this cancer. The improved isotachophoretic method described in this study is suitable for comparing the overall profile of autoimmunity between different populations and for subsequent identification of relevant antigens.