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PubMed1991

Cell and receptor requirements for streptococcal pyrogenic exotoxin T-cell mitogenicity.

Streptococcal pyrogenic exotoxins (SPEs) A, B, and C, like other members of the pyrogenic toxin family, are able to cause toxic shock-like syndromes. One of the major properties of these toxins is the ability to induce T-cell proliferation. Characterization of T cell mitogenicity associated with SPEs A, B, and C was undertaken. SPEs A, B, and C were mitogenic for C57BL10/SnJ and BALB/cWAT T cells, with activities differing in intensity depending on the mouse strain and toxin employed. SPE-induced, T-cell-proliferative activity was dependent on class II major histocompatibility complex molecules expressed on antigen-presenting cells. The abilities of SPEs A, B, and C to preferentially stimulate murine cells with certain T-cell receptor V beta s were investigated by fluorescence-activated cell sorter analysis. SPE A preferentially activated T cells expressing V beta 8 but not V beta 3, 6, or 11, while SPEs B and C preferentially stimulated T cells which did not express any of the tested V beta s.

Animals↗
PubMed1995

Revised sequence of the Porphyromonas gingivalis prtT cysteine protease/hemagglutinin gene: homology with streptococcal pyrogenic exotoxin B/streptococcal proteinase.

The prtT gene from Porphyromonas gingivalis ATCC 53977 was previously isolated from an Escherichia coli clone possessing trypsinlike protease activity upstream of a region encoding hemagglutinin activity (J. Otogoto and H. Kuramitsu, Infect. Immun. 61;117-123, 1993). Subsequent molecular analysis of this gene has revealed that the PrtT protein is larger than originally reported, encompassing the hemagglutination region. Results of primer extension experiments indicate that the translation start site was originally misidentified. An alternate open reading frame of nearly 2.7 kb, which encodes a protein in the size range of 96 to 99 kDa, was identified. In vitro transcription-translation experiments confirm this size, and Northern (RNA) blot experiments indicate that the protease is translated from a 3.3-kb mRNA. Searching the EMBL protein database revealed that the amino acid sequence of the revised PrtT is similar to sequences of two related proteins from Streptococcus pyogenes. PrtT is 31% identical and 73% similar over 401 amino acids to streptococcal pyrogenic exotoxin B. In addition, it is 36% identical and 74% similar over 244 amino acids with streptococcal proteinase, which is closely related to streptococcal pyrogenic exotoxin B. The similarity is particularly high at the putative active site of streptococcal proteinase, which is similar to the active sites of the family of cysteine proteases. Thus, we conclude that PrtT is a 96- to 99-kDa cysteine protease and hemagglutinin with significant similarity to streptococcal enzymes.

Amino Acid Sequence↗
PubMed1995

Mitogenicity of M5 protein extracted from Streptococcus pyogenes cells is due to streptococcal pyrogenic exotoxin C and mitogenic factor MF.

M proteins of Streptococcus pyogenes are virulence factors which impede phagocytosis, bind to many plasma proteins, and induce formation of cross-reactive autoimmune antibodies. Recently, it has been reported that some M proteins, extracted with pepsin from streptococci (pep M), are superantigens. One of these, pep M5, was investigated in detail and was shown to stimulate human T cells bearing V beta 2, V beta 4, and V beta 8. In the present study, we extracted and purified M5 protein by different biochemical methods from two M type 5 group A streptococcal strains. The crude extracts were fractionated by affinity chromatography and ion-exchange chromatography. All fractions were tested in parallel for M protein by immunoblotting and for T-cell-stimulating activity. Although several crude preparations of M5 protein were associated with mitogenicity for V beta 2 and V beta 8 T cells, the M5 proteins, irrespective of the extraction method, could be purified to the extent that they were no longer mitogenic. The mitogenic activity was not destroyed during the purification procedures but was found in fractions separated from M protein. In these fractions, streptococcal pyrogenic exotoxin C and mitogenic factor MF could be detected by protein blotting and enzyme-linked immunosorbent assay. Moreover, anti-M protein sera did not inhibit the mitogenic activity of crude extracts, but antisera which contained anti-streptococcal pyrogenic exotoxin C antibodies showed inhibition. The inability of M5 protein to stimulate T cells was confirmed with recombinant pep M5 produced in Escherichia coli. Our data strongly suggest that the mitogenic activity in M protein preparations is caused by traces of streptococcal superantigens different from M protein.

Amino Acid Sequence↗
PubMed1987

Leukocytic pyrogen effects on prostaglandins in hypothalamic tissue slices.

Some studies suggest that leukocytic pyrogen (LP) increase hypothalamic prostaglandins which, in turn, affect hypothalamic thermoregulatory neurons to produce fever. The present study used radioimmunoassays to quantitate the ability of guinea pig hypothalamic tissue slices to produce prostaglandin E2 (PGE2), prostaglandin F2 alpha (PGF2 alpha), 6-keto-prostaglandin F1 alpha (6-keto-PGF1 alpha), and thromboxane B2 (TxB2). Dose- and time-dependent prostaglandin increases occurred when these slices were perfused with LP media. Steady-state levels of tissue release were reached at 0-3 min for 6-keto-PGF1 alpha, at 6-9 min for PGE2 and PGF2 alpha, and at 12-15 min for TxB2. With the exception of 6-keto-PGF1 alpha, all substances showed continuous dose-response relationships for concentrations ranging from 0.001 to 0.25 LP dilutions. Tissue PGE2, for example, was 0.7 pg X min-1 X mg-1 with the 0.001 LP dilution and 8.7 pg X min-1 X mg-1 with the 0.25 LP dilution. Indomethacin blocked much of the LP-induced prostaglandin increase. Although there is a relationship between hypothalamic LP and prostaglandins in response to physiological LP levels, tissue prostaglandins are several orders of magnitude lower than concentrations necessary to produce fever by hypothalamic microinjection. This suggests that prostanoids, such as PGE2, may not be the sole mediators of fever induced by leukocytic pyrogen.

Animals↗
PubMed1994

Outbreak of pyrogenic reactions and gram-negative bacteremia in a hemodialysis center.

Six episodes of gram-negative bacteremia and seven pyrogenic reactions occurred in 11 patients in one hemodialysis center. Gram-negative bacteremias and/or pyrogenic reactions were not related to reuse and were more likely to occur if dialysis was performed in one unit of the center (8/13 unit 5 vs. 221/1,151 in other units, p < 0.001) and with one type of dialysis machine (10/13 vs. 581/1,151 with other machines, p = 0.05), which was preferentially used in unit 5 (p < 0.01). Bacterial and endotoxin concentrations of water used to prepare dialysate and reprocess hemodialyzers, and of dialysate, exceeded allowable concentrations recommended by the Association for the Advancement of Medical Instrumentation (AAMI). The implicated dialysis machines were disinfected with chemicals daily, but not heat-disinfected daily as suggested by the manufacturer. Results suggest that the outbreak was caused by the use of water that did not meet AAMI standards and inadequate disinfection of one type of dialysis machine.

Adult↗
PubMed1994

[Application of the Limulus test for practical quality control on endotoxin content in commercial human serum albumin (HSA) products. In comparison with the rabbit pyrogen test].

The bacterial endotoxin content in human serum albumin (HSA) products measured by two different Limulus amebocyte lysate (LAL) test methods, colorimetric and kinetic turbidimetric methods, were compared. So far as endotoxin-specific LAL reagents which do not show a false-positive reaction with (1-->3)-beta-D-glucan are used, a definite correlation was found between the results with the two LAL test methods. Endotoxin added to HSA products was recovered in a quantitative manner showing neither inhibition nor enhancement by HSA to the both LAL test methods. Results of the LAL tests showed a significant correlation with that of the rabbit pyrogen test. The correlation was much improved with endotoxin-added HSA. The present results indicate the practical applicability of the LAL test as an alternative method for the rabbit pyrogen test.

Animals↗
PubMed1992

Pyrogenic reactions in patients receiving conventional, high-efficiency, or high-flux hemodialysis treatments with bicarbonate dialysate containing high concentrations of bacteria and endotoxin.

High-efficiency (HE) and high-flux (HF) hemodialysis are becoming increasingly popular methods for treating patients with chronic renal failure because they reduce the time required for dialysis treatment. HF and HE dialyzers require bicarbonate dialysate, often prepared from concentrates that can support bacterial growth with endotoxin production. There is a concern that endotoxins or bacteria may cross or interact at the membranes of these dialyzers, triggering the release of endogenous pyrogens (cytokines) by peripheral blood mononuclear cells to cause pyrogenic reactions (PR). To determine the incidence of PR and to examine the association between PR and levels of bacteria and endotoxin in dialysate, a cohort of patients receiving conventional, HE, or HF hemodialysis with bicarbonate dialysate and reprocessed dialyzers at three dialysis centers during a 12-month period was studied prospectively. All dialyzers underwent a test of membrane integrity before use. A total of 19 PR were identified among 18 patients in 26,877 hemodialysis treatments (0.7 PR/1,000 treatments). There was no significant difference in PR rates by treatment modality: conventional, 0.5 per 1,000 (7 PR/13,123 treatments) versus HE, 0.9 per 1,000 (9 PR/11,345) versus HF, 1.2 per 1,000 (3 PR/2,409) (P = 0.21; chi 2 test). Throughout the study period, bacterial counts for dialysate at each center significantly exceeded the Association for the Advancement of Medical Instrumentation's (AAMI) microbiologic standards for dialysate of less than 2,000 CFU/mL (mean, 19,000 CFU/mL), but water used in the reuse of dialyzers tested less than 200 CFU/mL.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1980

Pyrogenic reactions after inadvertent infusion of endotoxin during cardiac catheterizations.

In April 1976 the attack rate of chills and fever with or without falls in blood pressure increased in association with cardiac catheterizations. Fevers were associated with coronary angiography and right and left heart catheterizations. Blood cultures were negative, and reactions did not correlate with amounts of contrast materials infused or with procedures done by a single operator. Significant numbers of Acinetobacter calcoaceticus (var. anitratus) and a Pseudomonas species were cultured from hospital-reservoir distilled water when it was flushed through a catheter before gas sterilization. This same water after ethylene oxide sterilization contained 2 x 10(5) ng/mL of endotoxin by limulus lysate test and was positive by rabbit pyrogen test. When washed reusable cardiac catheters were sterilized daily or when disposable catheters were substituted, febrile reactions ended. Pyrogenic reactions in patients undergoing cardiac catheterizations correlated with emptying retained endotoxin with injected contrast material from reused washed-sterilized catheters.

Acinetobacter↗
PubMed2002

The rostral raphe pallidus nucleus mediates pyrogenic transmission from the preoptic area.

Fever is the widely known hallmark of disease and is induced by the action of the nervous system. It is generally accepted that prostaglandin (PG) E(2) is produced in response to immune signals and then acts on the preoptic area (POA), which triggers the stimulation of the sympathetic system, resulting in the production of fever. Actually, the EP3 subtype of PGE receptor, which is essential for the induction of fever, is known to be localized in POA neurons. However, the neural pathway mediating the pyrogenic transmission from the POA to the sympathetic system remains unknown. To identify the neuronal groups involved in the fever-inducing pathway, we first investigated Fos expression in medullary regions of rats after central administrations of PGE(2). PGE(2) application to the lateral ventricle or directly to the POA strikingly increased the number of Fos-positive neurons in the rostral part of the raphe pallidus nucleus (rRPa). Most of these neurons did not exhibit serotonin immunoreactivity. Microinjection of muscimol, a GABA(A) receptor agonist, into the rRPa blocked fever and thermogenesis in brown adipose tissue induced by intra-POA as well as by intracerebroventricular PGE(2) applications. Furthermore, neural tract tracing studies revealed a direct projection from EP3 receptor-expressing POA neurons to the rRPa. Our results demonstrate that the rRPa, which has never been associated with the fever mechanism, mediates the pyrogenic neurotransmission from the POA to the peripheral sympathetic effectors contributing to fever development.

Adipose Tissue, Brown↗
PubMed1997

[Effects of both puerarin and gypsum on the firing of pyrogen-treated thermosensitive neurons in the region POAH of anesthetized cats].

To investigate the possible central mechanism of antipyretic effects of Chinese medicines, puerarin and gypsum, the firing rate of thermosensitive neurons in preoptic-anterior hypothalamus (POAH) region of 34 cats was recorded by using extracellular micro-electrode technigue. Injection of pyrogen caused decrease in firing rate of 14 warm-sensitive neurons and increase in firing rate of 11 cold-sensitive neurons in the region of POAH. The effects could be reversed by the injection of puerarin and gypsum. The results showed the antipyretic action of puerarin and gypsum might be mediated by influences on the electroactivity of pyrogen-treated thermosensitive neurons in the region of POAH. Effect of puerarin and gypsum on cold-sensitive neurons was stronger than that of single one, suggesting that both are synergic in central level.

Action Potentials↗
PubMed1983

Pyrogen contamination of total parenteral nutrition solutions: a case report.

Parenteral nutrition solutions are prepared at The Hospital for Sick Children using a bulk-processing method. The article documents an episode of pyrogen contamination, its detection, investigation and outcome. The source of contamination was found to be specific pieces of the bulk-run equipment which are no longer used. In addition, faulty quality control systems were identified and corrected. Like all intravenous fluids parenteral nutrition solutions can be pyrogenic. Careful preparation and adequate quality control procedures can prevent this problem from occurring. The bulk-processing method can be used to produce large quantities of TPN solutions in a safe and efficient manner.

Drug Contamination↗
PubMed1991

Interleukin-4 counteracts pyrogen-induced downregulation of thrombomodulin in cultured human vascular endothelial cells.

Inflammatory mediators such as tumor necrosis factor (TNF) or interleukin-1 (IL-1) and bacterial lipopolysaccharides (LPS) were shown to shift the hemostatic balance of the endothelial cell (EC) surface in favor of procoagulant activities by inducing tissue factor (TF) expression and downregulation of thrombomodulin (TM). In the present study, the effects of IL-4 on these regulatory mechanisms were investigated using cultured human umbilical vein EC. TM downregulation induced by the pyrogens IL-1 (100 U/mL), TNF (500 U/mL), and LPS (20 micrograms/mL) to less than 50% of TM activity of untreated cells during a 12-hour incubation period was completely neutralized when these mediators were coincubated with IL-4 (100 U/mL). In accordance with TM surface activity, TM messenger RNA was decreased by IL-1, TNF, and LPS to less than 40% of untreated cells; this effect was in part antagonized by IL-4. No influence of IL-4 on EC tissue factor induction by IL-1, TNF, and LPS was found. Binding studies using 125I-radiolabeled IL-4 suggest that EC express a single class of high-affinity binding sites (kd = 3.2 pmol/L; 2,000 to 2,500 receptors per cell). These results show that IL-4, in part, protects the EC surface against pyrogen-induced procoagulant changes. Transcriptional regulatory mechanisms seem to be involved in EC surface TM regulation.

Cell Membrane↗
PubMed1991

Extracellular serotonin levels change with behavioral state but not with pyrogen-induced hyperthermia.

Extracellular 5-HT in the anterior hypothalamus/preoptic area (AH/POA) and caudate nucleus of the freely moving cat was measured using in vivo brain microdialysis. Administration of 8-OH-DPAT, a 5-HT1A receptor agonist that decreases 5-HT neuronal activity, decreased extracellular 5-HT in both brain areas. Extracellular 5-HT levels were also examined in relationship to the sleep-wake cycle, because previous data from our laboratory have indicated that behavioral state is the primary determinant of 5-HT neuronal discharge. As with 5-HT neuronal discharge, extracellular 5-HT was increased during active behavioral states and decreased during somnolent periods. These first two sets of findings confirm the ability of the microdialysis technique to measure physiological fluctuations in extracellular 5-HT levels and support the hypothesis that neuronal discharge is a major determinant of extracellular 5-HT levels. Levels of the 5-HT metabolite 5-hydroxyindole acetic acid (5-HIAA) in the AH/POA were also responsive to changes in behavioral state and administration of 8-OH-DPAT, though fluctuations in extracellular 5-HIAA were less robust and temporally delayed. Finally, extracellular 5-HT and 5-HIAA were examined in the AH/POA during fever induced by systemic injection of the synthetic pyrogen muramyl dipeptide. Previous data from our laboratory have indicated that 5-HT neuronal activity is unaffected by this manipulation, though 5-HT has been implicated specifically in thermoregulation. Pyrogen-induced hypothermia produced no specific change in 5-HT efflux, because any changes noted could be accounted for by behavioral state changes. These data are consistent with the hypothesis that the brain serotonergic system is closely linked to the sleep-wake-arousal cycle. However, extracellular 5-HT may be involved in thermoregulatory processes as part of a global role in modulating neuronal activity in coordination with the behavioral state of the animal.

8-Hydroxy-2-(di-n-propylamino)tetralin↗
PubMed1991

Fever in young lambs: temperature, metabolic and cardiorespiratory responses to a small dose of bacterial pyrogen.

Experiments were done on ten lambs ranging in age from 15 to 25 days to define the temperature, metabolic and cardiorespiratory responses to intravenous administration of a small dose of bacterial pyrogen (SAE). Administration of SAE but not normal saline produced a short-lived fever of about 0.7 degrees C. The increase in body-core temperature was preceded by a surge in total body oxygen consumption and the onset of shivering which was influenced by behavioral state (ie, shivering was inhibited during active sleep). The increase in total body oxygen consumption was initially met by an increase in total body oxygen extraction and then by an increase in systemic oxygen delivery. Systemic arterial blood pressure did not change significantly during the febrile response; however, pulmonic arterial blood pressure increased significantly. Thus, our experiments provide new data on oxygen supply and demand during the development of fever and that shivering thermogenesis is inhibited in active sleep following the administration of bacterial pyrogen in young lambs. The influence of active sleep on the overall febrile response, and whether or not there is a shift from shivering thermogenesis to non-shivering thermogenesis remains to be determined.

Animals↗
PubMed1990

[Stimulation of the synthesis of C-reactive protein using pyrogenal in non-neoplastic diseases and cancer of the lungs].

Method of immunodiffusion titration of rabbit monospecific antiserum (The I. M. Mechnikov Central Research Institute of Vaccines and Sera of the USSR Ministry of Health) in agar was used to measure blood C-reactive protein (C-RP) level in patients with acute pneumonia (32), protracted pneumonia or activation of chronic non-specific lung pathology (101) and lung cancer (153) after a 3-4-week course of complex antiinflammatory treatment and a 10-14-day course of immunostimulation with pyrogenal (The N. F. Gamaleya Research Institute of Epidemiology and Microbiology). A decrease in the incidence (from 81.2% to 14.2%) and level (from 1.4 +/- 0.3 to 0.3 +/- 0.03 mg%) of C-RP was observed in cases of non-tumor pathology whereas in patients with lung cancer those values rose in step with tumor progression (from 72.2% and 0.4 +/- 0.07 mg% at stage I to 96.3% and 1.2 +/- 0.12 mg% at stage IV). Treatment with pyrogenal allowed to identify C-RP in patients with false-negative reaction in all subgroups. Two-week dynamic C-RP curves characterizing non-tumor and tumor pathology of the lung were plotted.

Anti-Inflammatory Agents, Non-Steroidal↗
PubMed1987

[Role of bacterial lipopolysaccharide pyrogenal in the development of congenital defects in embryos of second-generation Syrian hamsters].

Effect of bacterial lipopolysaccharide (pyrogenal) on development of golden hamster embryos of the second generation has been studied. The female hamsters are given pyrogenal once--intramuscularly 500-625 mpd/kg on the 9th-14th day of pregnancy. The embryos of the second generation are examined on the 15th day of pregnancy. The external observation is performed, body mass is estimated, state of the internal organs is studied. Death and congenital defects of development are essential among the embryos after implantation. Among alive embryos the congenital defects are noticed in 30% of cases, among the dead ones--in 63%. In the control group the congenital defects are found in 1.7% of cases.

Abnormalities, Drug-Induced↗
PubMed1984

Chemotactic cytokines: the role of leukocytic pyrogen and epidermal cell thymocyte-activating factor in neutrophil chemotaxis.

Macrophage-derived leukocytic pyrogen (LP) is thought to be similar if not identical to interleukin 1 (IL 1). In addition to macrophages, keratinocytes produce a factor that has similar biologic and biochemical characteristics to IL 1, called epidermal cell thymocyte-activating factor (ETAF). Because many diseases affecting the skin are characterized by infiltration of polymorphonuclear leukocytes (PMN) and some of these disorders are associated with fever, we investigated whether ETAF like LP had pyrogenic activity, and whether ETAF or LP were chemoattractants. ETAF or LP purified by column chromatography and isoelectric focusing were found to have chemotactic activity for PMN. The fractions containing maximal chemotactic activity corresponded to maximal fever-inducing activity and maximum thymocyte-activating activity. Furthermore, the chemotactic activity of ETAF and LP could be blocked by an antibody directed against LP. The results of this study indicate that these mediators, which arise from distinct cell populations, are closely related and may play a vital role in skin as well as distant inflammatory and immunologic events.

Animals↗
PubMed1964

PATHOGENESIS OF INFLAMMATION. I. THE PRODUCTION OF AN INFLAMMATORY SUBSTANCE FROM RABBIT GRANULOCYTES IN VITRO AND ITS RELATIONSHIP TO LEUCOCYTE PYROGEN.

Material obtained from the in vitro incubation of granulocytes from saline-induced peritoneal exudates of rabbits has been shown to produce inflammation and fever in rabbits. The supernatant material from cells incubated in saline has been termed granulocytic substance (GS) and is heat-labile. Its production is temperature dependent, occurring at 37 degrees C but not at 4 degrees C, requires viable cells, and is inhibited by potassium ions. A similar material is liberated when cells are incubated in a more physiologic medium. Freezing and thawing of granulocytes does not release GS and the active principle cannot be obtained from the incubation of lymphocytes. GS produces a delayed inflammatory response as measured by leucocyte sticking and emigration in the rabbit ear chamber and the leakage of protein-conjugated dye at the site of intradermal injection. The former response can be accurately quantitated by calculation of the inflammatory index from reactions observed in the ear chamber. The inflammatory reaction and the properties of GS distinguish it from a variety of previously described mediators of inflammation, but GS appears to be identical with leucocytic pyrogen. The possible role of GS in delayed and protracted inflammation and its relationship to the pathogenesis of fever are discussed.

Animals↗