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Risk of developing toxic shock syndrome associated with toxic shock syndrome toxin 1 following nongenital staphylococcal infection.

Few risk factors for nonmenstrual toxic shock syndrome (TSS) have been identified. This study sought to determine at what rate and under what circumstances nongenital toxigenic Staphylococcus aureus infections led to TSS. Clinical isolates of S. aureus were examined for the production of TSS toxin 1 (TSST-1), and available sera from infected patients were tested for antibody to this toxin. Twenty-six percent of 810 isolates produced TSST-1. Isolates from children were more likely to be positive for TSST-1 than were those from adults. None of 57 patients with TSST-1-positive staphylococcal infection and a TSST-1 antibody titer of greater than or equal to 1:100 developed TSS. Eight of 65 tested patients with TSST-1-positive isolates had antibody below the presumably protective level of 1:100. Two of these patients had definite TSS, three had probable or possible TSS, and three probably did not have TSS. In patients lacking protective antibody to TSST-1, the interval between acquisition and infection with staphylococci, the type and amount of toxins produced, the site of infection, and still-unclarified aspects of host susceptibility may all affect the rate and severity of TSS.

Adult↗

A mycobacterial heat-shock protein-responsive gamma delta T cell clone also responds to the homologous human heat-shock protein: a possible link between infection and autoimmunity.

Prokaryotic and eukaryotic cells respond to a variety of stress conditions by increasing the synthesis of a family of proteins collectively known as heat-shock proteins (HSP). One of these, a 65-kDa HSP that is highly conserved in many bacteria, is a major target of the immune response to mycobacteria. A gamma delta T cell clone from a healthy donor that recognizes not only the 65-kDa mycobacterial HSP but also the recombinant human homologue of this HSP protein was raised. Like alpha beta T cell clones, which recognize mycobacterial HSP, the clone requires antigen-presenting cells for antigen-induced proliferation and can also be directly activated via receptor cross-linking through CD3 or the delta chain of the gamma delta T cell receptor. These data suggest that the induction of a gamma delta T cell response by bacterial antigens could lead to the expansion of cells that respond to autologous proteins and, therefore, may result in the development of autoimmunity.

Antigen-Presenting Cells↗

Expression of heat shock factor 2 in mouse testis: potential role as a regulator of heat-shock protein gene expression during spermatogenesis.

We have examined the expression and function of heat shock transcription factor 2 (HSF2) in spermatogenic cells of mouse testis. The results of in situ RNA hybridization analysis, RNA filter hybridization, and reverse transcription-polymerase chain reaction (RT-PCR) analysis indicate that HSF2 mRNA expression in testis is subject to developmental and cell type-dependent, as well as stage-dependent, regulation. Localized expression of HSF2 mRNA in testis first appears between Day 14 and Day 21 of postnatal development. In adult testis, HSF2 mRNA is found at highest levels in spermatocytes and round spermatids. Immunocytochemical staining and gel mobility shift analysis demonstrate that HSF2 protein is localized to the nuclei of spermatocytes and round spermatids and that this transcription factor exists in testis in a constitutively active DNA-binding state. We further demonstrate that the constitutive HSF2 DNA-binding activity present in testis is able to interact with promoter sequences of the hsp70.2 gene, a testis-specific member of the hsp70 gene family. Taken together, our results show that the expression and functional properties of HSF2 are regulated in spermatogenic cell types of the mouse testis, supporting a role for this transcription factor as a regulator of hsp gene expression during spermatogenesis.

Animals↗

Heat shock response and heat shock protein antigens of Vibrio cholerae.

Sixteen heat shock proteins (Hsps) have been identified in the hypertoxinogenic strain 569B of Vibrio cholerae which are synthesized in response to small and large elevations of temperature. The induction of the Hsps is necessary for the cells to survive the deleterious effects of heat. There is no difference in the pattern of induction of the Hsps in V. cholerae strains varying in levels of toxinogenicity. One of the major low-molecular-mass Hsps, a 16-kDa protein, is preferentially degraded following shift down of temperature. This protein is induced at a much lower level at high temperatures in cells maintained in the laboratory for a prolonged period. The only Hsp located in the outer membrane of V. cholerae cells is a 23-kDa protein. Western immunoblot analysis with human immune sera collected from convalescent cholera patients revealed that this protein is markedly immunogenic. The human immune serum also reacted with the 69- and 16-kDa major Hsps and the 88-, 66-, and 46-kDa Hsps but not with the 61-kDa major Hsp identified as the groEL gene product. All major Hsps reacted with rabbit anti-V. cholerae sera. Ethanol stress leads to the induction of four of the major Hsps and three additional proteins.

Adaptation, Biological↗

Overexpression of wild-type heat shock protein 27 and a nonphosphorylatable heat shock protein 27 mutant protects against ischemia/reperfusion injury in a transgenic mouse model.

BACKGROUND: The small heat shock protein 27 (hsp27) increases in expression with ischemia/reperfusion (I/R) insult in the heart. One feature of the small hsps is their ability to oligomerize and form intracellular aggregates. Oligomerization pattern is governed by the phosphorylation state of the protein that may influence their ability to protect against cellular stresses. METHODS AND RESULTS: We generated transgenic (tg) mice that overexpress a wild-type human hsp27 (hsp27tg) protein or a mutant hsp27 protein (mut-hsp27tg), in which serine residues (aa15, aa78, and aa82) were replaced by alanine residues, rendering them incapable of phosphorylation. Using a Langendorff perfusion model and an intraventricular balloon, we subjected hearts to 20 minutes of ischemia followed by 1 hour of reperfusion. During reperfusion, negative and positive pressure derivatives as well as developed pressures were significantly higher in both hsp27tg and mut-hsp27tg compared with control (P<0.01) mice, with no significant difference between hsp27tg and mut-hsp27tg. Creatine kinase release during reperfusion was higher in control compared with both hsp27tg and mut-hsp27tg (P<0.05). Malondialdehyde content as well as protein oxidation products were lower in mut-hsp27tg compared with control (P<0.05). hsp27tg hearts possessed oligomers that ranged in size from small to large, whereas mut-hsp27tg hearts contained no small oligomers. CONCLUSIONS: These results indicate that in a tg mouse model, overexpression of either wild-type hsp27 or a nonphosphorylatable hsp27 mutant was equally capable of protecting the heart from I/R injury. Furthermore, the phosphorylation status of hsp27 may influence its ability to decrease oxidative stress.

Amino Acid Substitution↗

Endothelial cytotoxicity mediated by serum antibodies to heat shock proteins of Escherichia coli and Chlamydia pneumoniae: immune reactions to heat shock proteins as a possible link between infection and atherosclerosis.

BACKGROUND: Growing evidence suggests that an immunological reaction against heat shock proteins (HSPs) may be involved in atherogenesis. Because HSPs show a high degree of amino acid sequence homology between different species, from prokaryotes to humans, we investigated the possibility of "antigenic mimicry" caused by an immunological cross-reaction between microorganisms and autoantigens. METHODS AND RESULTS: Serum antibodies against the Escherichia coli HSP (GroEL) and the 60-kDa chlamydial HSP (cHSP60) from subjects with atherosclerosis were purified by use of affinity chromatography. Western blot analyses and competitive ELISAs confirmed the cross-reaction of the eluted antibodies with human HSP60 and the bacterial counterparts. The cytotoxicity of anti-GroEL and anti-cHSP60 antibodies was determined on human endothelial cells labeled with 51Cr. A significant difference (40% versus 8%) was observed in the specific 51Cr release of heat-treated (42 degrees C for 30 minutes) and untreated cells, respectively, in the presence of these anti-HSP antibodies and complement. This effect was blocked by addition of 100 microg/mL recombinant GroEL. In addition, seropositivity against specific non-HSP60 Chlamydia pneumoniae antigens is more prominent among high-anti-HSP titer sera than low-titer sera. CONCLUSIONS: Serum antibodies against HSP65/60 cross-react with human HSP60, cHSP60, and GroEL; correlate with the presence of antibodies to C pneumoniae and endotoxin; and mediate endothelial cytotoxicity. These findings suggest that humoral immune reactions to bacterial HSPs, such as cHSP60 and GroEL, may play an important role in the process of vascular endothelial injury, which is believed to be a key event in the pathogenesis of atherosclerosis.

Adult↗

Increased expression of heat shock protein 65 coincides with a population of infiltrating T lymphocytes in atherosclerotic lesions of rabbits specifically responding to heat shock protein 65.

We have shown previously that atherosclerotic lesions can be induced in normocholesterolemic rabbits by immunization with mycobacterial heat shock protein 65 (hsp65), which has a high degree of sequence homology with mammalian hsp60. To investigate a possible relationship between hsp60 expression and the antigenic specificities of infiltrating T cells in the lesion, 38 New Zealand White rabbits were treated either by immunization with recombinant mycobacterial hsp65 or by administration of a 0.2% cholesterol diet. Atherosclerotic lesions were observed after 16 wk, particularly in the aortic arch and arterial bifurcations of rabbits immunized with hsp65 or fed with a cholesterol-rich diet. Hsp65 staining of aortas showed a heterogeneous distribution, and significantly increased staining intensity in atherosclerotic lesions compared to aortic media or adventitia. This abundantly expressed hsp65 was observed in atherosclerotic lesions induced by hsp65 immunization as well as those induced by cholesterol-rich diet alone. Interestingly, a population of the T lymphocytes isolated from all forms of atherosclerotic lesions specifically responded to hsp65 in vitro. IL-2-expanded T cell lines derived from atherosclerotic lesions showed a significantly higher hsp65 reactivity than those developed from peripheral blood of the same donor. Furthermore, levels of circulating antibodies and numbers of spleen cells specifically reacting against hsp65 were elevated in all experimental animals. Flow cytometric analysis of spleen cells showed elevated immune response-associated antigen expression in treated animals. In conclusion, increased hsp65 expression in intimal cells and the presence of hsp65-specific T cells in blood and in atherosclerotic lesions may be important in initiating the development of atherosclerosis and perpetuating the lesions.

Animals↗

Heat shock protein 70 or heat shock protein 27 overexpressed in human endothelial cells during posthypoxic reoxygenation can protect from delayed apoptosis.

Overexpression of heat shock protein (Hsp) 70 and Hsp27 in vivo was proclaimed as a potential tool in therapy of ischemia-reperfusion injury. However, it was so far not known whether these Hsps can beneficially act when increased in cells just at the stage of postischemic reperfusion. This issue was examined in a model of ischemia-reperfusion stress when cultures of endothelial cells (EC) from human umbilical vein were infected with virus-based vectors expressing Hsp70 or Hsp27, or Hsp56, or green fluorescent protein (GFP) and exposed to 20 hours of hypoxia followed by reoxygenation. The infection was performed either 10 hours before hypoxia or immediately after hypoxia, or at different time points of reoxygenation. Only low cell death was detected during hypoxia, but later, up to 40% of the treated cells died via caspase-dependent apoptosis between 6 and 12 hours of reoxygenation. The percentage of apoptotic cells was 1.6- to 3-fold greater in Hsp56- and GFP-infected EC than in Hsp70- or Hsp27-infected EC. The last 2 groups exhibited a lesser extent of procaspase-9 and procaspase-3 activation within 6-9 hours of reoxygenation. The cytoprotective effects of overexpressed Hsp70 and Hsp27 were observed not only in the case of infection before hypoxia but also when EC were infected at the start of reoxygenation or 1-2 hours later. An increase in the Hsp70 and Hsp27 levels in infected EC correlated well with their resistance to apoptosis under reoxygenation. These findings suggest that overexpression of Hsp70 or Hsp27, if it occurs in the involved cells at the early stage of postischemic reperfusion, can still be cytoprotective.

Apoptosis↗

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.

Adult↗

[Hemorrhagic shock. A new concept of endoscopic hemostasis and prospects of the non-surgical treatment of ulcer and gastroduodenal hemorrhages complicated by hemorrhagic shock].

A new direction with the use of endoscopic hemostasis (EH) was offered in the complex program of metabolic rehabilitation of patients with ulcerous gastroduodenal bleedings (UGDB) and hemorrhagic shock (HS). There was a study of the results of treatment of 44 patients (29 men and 15 women at the age from 61 to 77) with severe concurrent diseases and UGDB complicated with HS. Recurrences of UGDB in case of HS are a factor of high operative-anesthetic risk. Endoscopic preventive metabolic hemostasis is a prospective direction in rehabilitation of patients with UGDB complicated with HS. It is necessary to improve the EH methods for treatment of continued arterial bleedings from giant gastroduodenal ulcers.

Aged↗

[Studies of heat shock protein 60 and heat shock protein 70 in oral lichen planus].

OBJECTIVE: To study the role of heat shock protein (HSP) 60 and HSP70 in the pathogenesis of oral lichen planus (OLP). METHODS: The immunohistochemical SP methods were used to detected the expression of HSP60 and HSP70 in 62 cases of oral lichen planus, 10 cases of normal oral mucosa, 21 cases of chronic discoid lupus erythematosus (DLE), 10 cases of benign lymphoadenosis of mucosa, 46 cases of leukoplakia. RT-PCR was used to evaluate the expression of HSP60 mRNA and HSP70 mRNA in 12 cases of OLP and 5 cases of normal oral mucosa. RESULTS: HSP60 was expressed at much higher levels in OLP than other groups. The expression of HSP70 decreased in epithelial cells in erosive lichen planus group. HSP60 mRNA and HSP70 mRNA were expressed at high level in OLP. CONCLUSION: HSP60 and HSP70 play an important role in pathogenesis of OLP.

Chaperonin 60↗

[A procedure for infusion-transfusion therapy and autohemodilution in severe trauma and shock (apropos the article by B. N. Salamatin et al., The use of the "internal autotransfusion" method in complex shock-control measures at the prehospital stage)].

The infusion of hypertonic solution is thought by the authors to be effective due to its reflectory action for treatment of patients who are in the state of anaphylactic and cardiogenic shock. This method seems to be expedient for massive blood loss under conditions of prehospital medical aid to victims with very low level of arterial pressure, with craniocerebral trauma and critical trauma of the chest.

Blood Transfusion, Autologous↗

Fluid resuscitation in circulatory shock: a comparison of the cardiorespiratory effects of albumin, hetastarch, and saline solutions in patients with hypovolemic and septic shock.

Twenty-six consecutive patients in hypovolemic shock were randomized to fluid challenge with 5% albumin (A), 6% hetastarch (H), or 0.9% saline (S) solutions. Fluid challenge consisted of 250 ml of test fluid every 15 min until the pulmonary artery wedge pressure (WP) reached 15 mm Hg. Thereafter, WP was maintained at 15 mm Hg for an additional 24 h with infusions of the same test fluid. Vital signs, hemodynamic and respiratory variables, as well as arterial lactate and colloid osmotic pressure (COP) were monitored according to protocol. Chest x-rays were performed by standardized technique before fluid challenge and at 12 and 24 h of maintenance fluid therapy and were evaluated for evidence of pulmonary edema. Cardiac function and hemodynamic stability were restored by fluid challenge with A, H, and S. Two to 4 times the volume of S as A or H was required to achieve similar hemodynamic endpoints. COP was increased by fluid challenge with A or H but was markedly reduced by fluid challenge with S and throughout the 24-h maintenance period. Fluid challenge resulted in reductions in COP-WP gradient of 62% in the A, 43% in the H, and 125% in the S groups. Resuscitation with S resulted in a significantly higher incidence of pulmonary edema (87.5%) than did resuscitation with A (22%) or H (22%). Urine output was not different among the groups at any time during the study. We conclude that 6% H performs as well as 5% A as a resuscitative fluid and that resuscitation with either of these colloids is associated with a lower incidence of pulmonary edema than is resuscitation with 0.9% S.

Aged↗

Heat shock induced changes of plant cell ultrastructure and autoradiographic localization of heat shock proteins.

Treating tomato cell cultures and leaves by a physiological heat shock (hs) at 35 to 39 degrees C results in a progressive disintegration of the nucleolus and the assembly of cytoplasmic hs granules. Other ultrastructural changes are not observed. The alterations of the nucleoli coincide with an immediate stop of the processing and with a strongly decreased synthesis of pre-rRNA. Both hs effects are reversed after shift-down to normal temperature conditions (25 degrees C). Assembly of cytoplasmic hs granules depends on the accumulation of the newly forming hs proteins and on supraoptimal temperatures. It is not observed in preinduced cultures synthesizing hs proteins at 25 degrees C. Autoradiographic studies reveal the preferential accumulation of hsp in the nucleoli and hs granules. Furthermore uridine labeling points to the presence of RNA in electron dense particles of both subcellular components. A survey on the state of hsp synthesis and structural binding as well as on the ultrastructural changes is given for 12 selected hs regimes.

Autoradiography↗

[Clinical significance of heat shock proteins. Influence of heat shock proteins on the pathomechanism of selected diseases].

The presentation shows the survey of diseases the pathogenesis of which might be connected with the existence of Heat Shock Proteins (HSPs). We discuss the data referring to the influence of the HSPs upon the occurrence and progression of the following diseases: systemic lupus erythematosus, reactive arthritis, rheumatoid arthritis, insulin dependent diabetes mellitus, schizophrenia and Alzheimer's disease. There is also indicated a possible activity of HSPs in the pathogenesis of neoplasia, organ ischaemia and inflammation or degeneration.

Alzheimer Disease↗