The Experts below are selected from a list of 17388 Experts worldwide ranked by ideXlab platform
C J Mahoney - One of the best experts on this subject based on the ideXlab platform.
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Pyrogenicity of etiocholanolone and interleukin 1 in new and old world monkeys
Experimental Biology and Medicine, 1998Co-Authors: Bernard G. Steinetz, Carla Randolph, R Werner, C J MahoneyAbstract:Etiocholanolone (5beta-androstan-3alpha-ol-17-one; designated E) is one of the major products of metabolism of testosterone and androstenedione (androst-4-ene-3,17-dione) in many mammalian species, including humans. E and several other 5beta-reduced steroids have been found to induce fever in humans. The pyrogenic effect of these steroids has been shown to be due to the release of interleukin-1 (IL-1) from the leukocytes that are mobilized in response to the steroid injections. Old World Monkeys such as Rhesus monkeys (Macaca mu/atta), metabolize androgens similarly to humans, and E is a normal metabolite. However, New World Monkeys such as Squirrel monkeys (Saimiri sciureus), lack hepatic 5alpha- and 5beta-steroid reductases and excrete androgens primarily in an unaltered state; E is not produced. Therefore, we postulate that Squirrel monkeys likewise may have lost the ability to respond to 17-ketosteroids such as E. To test this hypothesis, adult male Rhesus and Squirrel monkeys were treated with E, and their rectal temperatures were recorded over a 24-hr period. Rhesus monkeys exhibited a rise of up to 3 degrees F following E injection. Squirrel monkeys, on the other hand, did not exhibit any increase in rectal temperature over the 24-hr period, even when doses up to 250 times the effective human dose were used. However, both species responded to injected IL-1alpha with a robust increase in rectal temperature. The data show that E is pyrogenic in Rhesus, but not Squirrel monkeys. The findings support the notion that injected E may induce release of IL-1 in Rhesus monkeys, but not in Squirrel monkeys.
Thomas Hartung - One of the best experts on this subject based on the ideXlab platform.
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Assessment of pyrogenic contaminations with validated human whole-blood assay
Nature Protocols, 2009Co-Authors: Mardas Daneshian, Sonja Von Aulock, Thomas HartungAbstract:We present an internationally validated protocol for the evaluation of pyrogenic contaminations using human whole blood. In the in vitro pyrogen test (IPT) the sample is incubated with fresh or cryopreserved human whole blood, and the proinflammatory cytokine interleukin-1β (IL-1β) is detected by enzyme-linked immunosorbent assay (ELISA). In addition to detecting pyrogenic contaminations in aqueous samples, e.g., parenteral drugs; adaptations allow the assessment of lipidic, toxic or immunomodulatory substances; detection of low-grade contaminations in large-volume parenterals, e.g., dialysis water and fluids; Pyrogenicity assessment of solid materials, e.g., medical devices; and evaluation of airborne pyrogenic burden. In contrast to the rabbit pyrogen test and the limulus amoebocyte lysate (LAL) test, it requires no components of animal origin. In comparison with the LAL, it also detects nonlipopolysaccharide pyrogens. In comparison with other monocyte activation tests it requires no cell preparation steps or cell culture facilities. The procedure takes 21–35 h to complete.
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Assessment of pyrogenic contaminations with validated human whole-blood assay
Nature Protocols, 2009Co-Authors: Mardas Daneshian, Sonja Von Aulock, Thomas HartungAbstract:We present an internationally validated protocol for the evaluation of pyrogenic contaminations using human whole blood. In the in vitro pyrogen test (IPT) the sample is incubated with fresh or cryopreserved human whole blood, and the proinflammatory cytokine interleukin-1β (IL-1β) is detected by enzyme-linked immunosorbent assay (ELISA). In addition to detecting pyrogenic contaminations in aqueous samples, e.g., parenteral drugs; adaptations allow the assessment of lipidic, toxic or immunomodulatory substances; detection of low-grade contaminations in large-volume parenterals, e.g., dialysis water and fluids; Pyrogenicity assessment of solid materials, e.g., medical devices; and evaluation of airborne pyrogenic burden. In contrast to the rabbit pyrogen test and the limulus amoebocyte lysate (LAL) test, it requires no components of animal origin. In comparison with the LAL, it also detects nonlipopolysaccharide pyrogens. In comparison with other monocyte activation tests it requires no cell preparation steps or cell culture facilities. The procedure takes 21–35 h to complete.
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cryopreservation of human whole blood for Pyrogenicity testing
Journal of Immunological Methods, 2004Co-Authors: Stefanie Schindler, Thomas Hartung, Silvia Asmus, Sonja Von Aulock, Albrecht Wendel, Stefan FennrichAbstract:Abstract Human whole blood assays are increasingly employed to test immune function or detect pyrogenic contamination, since they offer advantages, such as ease of performance, few preparation artifacts and a physiological cell environment. However, the approach is often limited by the availability of freshly drawn blood, putative safety concerns in the case of infected donors and interindividual donor differences. To overcome these limitations, a method was developed and optimized to produce batches of cryopreserved blood that can be used directly after thawing without any washing steps. Mononuclear cells remained intact as shown by FACS analysis. Cytokine release could be induced by a variety of immunological stimuli. The cell preparation released higher amounts of interleukin-1β (IL-1β) and IL-6 compared to fresh blood, but no TNF. These differences could be attributed to the presence of the cryoprotectant dimethylsulfoxide (DMSO) alone by addition of DMSO to fresh blood. Large batches of cryopreserved blood could be produced by mixing blood donations of up to 10 donors, independent of differing blood groups. The detection limit for the World Health Organization (WHO) lipopolysaccharides (endotoxin, LPS) reference preparation (EC-6) with regard to the induction of IL-1β release was at least 0.5 endotoxin equivalent units (EU)/ml. Endotoxin spikes at the limit concentrations prescribed in the European Pharmacopoeia could be detected in a series of drugs, showing that the In vitro Pyrogen Test (IPT) can also be run with cryopreserved blood. Further possible applications include high-throughput screening for immunomodulators or toxins as well as preservation of patient samples for later analysis of cell functions.
Bernard G. Steinetz - One of the best experts on this subject based on the ideXlab platform.
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Pyrogenicity of etiocholanolone and interleukin-1 in New and Old World Monkeys.
Experimental Biology and Medicine, 1998Co-Authors: Bernard G. Steinetz, Carla Randolph, Werner R, Mahoney CjAbstract:AbstractEtiocholanolone (5β-androstan-3α-ol-17-one; designated E) is one of the major products of metabolism of testosterone and androstenedione (androst-4-ene-3,17-dione) in many mammalian species, including humans. E and several other 5β-reduced steroids have been found to induce fever in humans. The pyrogenic effect of these steroids has been shown to be due to the release of interleukin-1 (IL-1) from the leukocytes that are mobilized in response to the steroid injections.Old World Monkeys such as Rhesus monkeys (Macaca mulatta), metabolize androgens similarly to humans, and E is a normal metabolite. However, New World Monkeys such as Squirrel monkeys (Saimiri sciureus), lack hepatic 5α- and 5β- steroid reductases and excrete androgens primarily in an unaltered state; E is not produced. Therefore, we postulate that Squirrel monkeys likewise may have lost the ability to respond to 17-ketosteroids such as E.To test this hypothesis, adult male Rhesus and Squirrel monkeys were treated with E, and their rec...
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Pyrogenicity of etiocholanolone and interleukin 1 in new and old world monkeys
Experimental Biology and Medicine, 1998Co-Authors: Bernard G. Steinetz, Carla Randolph, R Werner, C J MahoneyAbstract:Etiocholanolone (5beta-androstan-3alpha-ol-17-one; designated E) is one of the major products of metabolism of testosterone and androstenedione (androst-4-ene-3,17-dione) in many mammalian species, including humans. E and several other 5beta-reduced steroids have been found to induce fever in humans. The pyrogenic effect of these steroids has been shown to be due to the release of interleukin-1 (IL-1) from the leukocytes that are mobilized in response to the steroid injections. Old World Monkeys such as Rhesus monkeys (Macaca mu/atta), metabolize androgens similarly to humans, and E is a normal metabolite. However, New World Monkeys such as Squirrel monkeys (Saimiri sciureus), lack hepatic 5alpha- and 5beta-steroid reductases and excrete androgens primarily in an unaltered state; E is not produced. Therefore, we postulate that Squirrel monkeys likewise may have lost the ability to respond to 17-ketosteroids such as E. To test this hypothesis, adult male Rhesus and Squirrel monkeys were treated with E, and their rectal temperatures were recorded over a 24-hr period. Rhesus monkeys exhibited a rise of up to 3 degrees F following E injection. Squirrel monkeys, on the other hand, did not exhibit any increase in rectal temperature over the 24-hr period, even when doses up to 250 times the effective human dose were used. However, both species responded to injected IL-1alpha with a robust increase in rectal temperature. The data show that E is pyrogenic in Rhesus, but not Squirrel monkeys. The findings support the notion that injected E may induce release of IL-1 in Rhesus monkeys, but not in Squirrel monkeys.
Patrick M. Schlievert - One of the best experts on this subject based on the ideXlab platform.
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Characterization of Staphylococcus aureus Enterotoxin L
Infection and Immunity, 2003Co-Authors: Paul M. Orwin, J. Ross Fitzgerald, Gregory A Bohach, Donald Y M Leung, Juan A. Gutierrez, Patrick M. SchlievertAbstract:Staphylococcus aureus causes a wide variety of diseases. Major virulence factors of this organism include enterotoxins (SEs) that cause both food poisoning and toxic shock syndrome. Recently, a novel SE, tentatively designated SEL, was identified in a pathogenicity island from a bovine mastitis isolate. The toxin had a molecular weight of 26,000 and an isoelectric point of 8.5. Recombinant SEL shared many biological activities with SEs, including superantigenicity, Pyrogenicity, enhancement of endotoxin shock, and lethality in rabbits when administered in subcutaneous miniosmotic pumps, but the protein lacked emetic activity. T cells bearing the T-cell receptor β chain variable regions 5.1, 5.2, 6.7, 16, and 22 were significantly stimulated by recombinant SEL.
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Characterization of a novel staphylococcal enterotoxin-like superantigen, a member of the group V subfamily of pyrogenic toxins.
Biochemistry, 2002Co-Authors: Paul M. Orwin, Timothy J. Tripp, Cathleen A. Earhart, Gregory A Bohach, Donald Y M Leung, Douglas H. Ohlendorf, Patrick M. SchlievertAbstract:Staphylococcus aureus is an important human pathogen, causing a variety of diseases. Major virulence factors of this organism include staphylococcal enterotoxins (SEs) that cause food poisoning and toxic shock syndrome. Our study identified a novel enterotoxin-like protein that is a member of the new subfamily (group V) of pyrogenic toxin superantigens (PTSAgs) and examined its biochemical and immunobiological properties. The gene encoding the SE-like protein is directly 5‘ of another recently identified PTSAg, SEK. The SE-like protein had a molecular weight of 26000 and an experimentally determined isoelectric point between 7.5 and 8.0. We demonstrated that the PTSAg had many of the biological activities associated with SEs, including superantigenicity, Pyrogenicity, and ability to enhance endotoxin shock, but lacked both lethality in rabbits when administered in subcutaneous miniosmotic pumps and emetic activity in monkeys. Recombinant protein stimulated human CD4 and CD8 T cells in a T cell receptor va...
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ImmuneCellLethality Induced byStreptococcal Pyrogenic Exotoxin A andEndotoxin
1992Co-Authors: Bettina A. B. Leonard, Patrick M. SchlievertAbstract:gelelectrophoresis andiodinated exotoxin overlays. Thisinteraction was demonstrated tobeimportant forimmunolethality, since simultaneous addition ofSPEA andLPSwas required, whereas sequential addition ofSPEAandLPSdidnotresult inlethality. LPSappeared tobeacting, inpart, toenhance thecell-binding ability ofSPEA,since SPEA could onlybedetected inA.E7 cell membrane preparations after simultaneous incubation withSPEA andLPS. Streptococcal pyrogenic exotoxin (SPE) A isamemberof thepyrogenic exotoxin family, consisting ofthestaphylococcal enterotoxins A through E,toxicshocksyndrome toxin-1 (TSST-1), andthestreptococcal scarlet fever toxins (SPEsA through C).Thepyrogenic toxins areconsidered to bethecausative agentsoftoxic shocksyndrome (TSS), and SPE A isassociated witha toxicshock-like syndrome (TSLS). SPEA shares itsbiological activities withother membersofthepyrogenic toxinfamily. Theseactivities include Pyrogenicity, enhancement oflethal endotoxin (lipopolysaccharide [LPS]) shock,andtheimmunobiological activities ofT-cell mitogenicity (superantigenicity), enhanced delayed-type hypersensitivity, erythrophagocytosis,
Mardas Daneshian - One of the best experts on this subject based on the ideXlab platform.
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Assessment of pyrogenic contaminations with validated human whole-blood assay
Nature Protocols, 2009Co-Authors: Mardas Daneshian, Sonja Von Aulock, Thomas HartungAbstract:We present an internationally validated protocol for the evaluation of pyrogenic contaminations using human whole blood. In the in vitro pyrogen test (IPT) the sample is incubated with fresh or cryopreserved human whole blood, and the proinflammatory cytokine interleukin-1β (IL-1β) is detected by enzyme-linked immunosorbent assay (ELISA). In addition to detecting pyrogenic contaminations in aqueous samples, e.g., parenteral drugs; adaptations allow the assessment of lipidic, toxic or immunomodulatory substances; detection of low-grade contaminations in large-volume parenterals, e.g., dialysis water and fluids; Pyrogenicity assessment of solid materials, e.g., medical devices; and evaluation of airborne pyrogenic burden. In contrast to the rabbit pyrogen test and the limulus amoebocyte lysate (LAL) test, it requires no components of animal origin. In comparison with the LAL, it also detects nonlipopolysaccharide pyrogens. In comparison with other monocyte activation tests it requires no cell preparation steps or cell culture facilities. The procedure takes 21–35 h to complete.
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Assessment of pyrogenic contaminations with validated human whole-blood assay
Nature Protocols, 2009Co-Authors: Mardas Daneshian, Sonja Von Aulock, Thomas HartungAbstract:We present an internationally validated protocol for the evaluation of pyrogenic contaminations using human whole blood. In the in vitro pyrogen test (IPT) the sample is incubated with fresh or cryopreserved human whole blood, and the proinflammatory cytokine interleukin-1β (IL-1β) is detected by enzyme-linked immunosorbent assay (ELISA). In addition to detecting pyrogenic contaminations in aqueous samples, e.g., parenteral drugs; adaptations allow the assessment of lipidic, toxic or immunomodulatory substances; detection of low-grade contaminations in large-volume parenterals, e.g., dialysis water and fluids; Pyrogenicity assessment of solid materials, e.g., medical devices; and evaluation of airborne pyrogenic burden. In contrast to the rabbit pyrogen test and the limulus amoebocyte lysate (LAL) test, it requires no components of animal origin. In comparison with the LAL, it also detects nonlipopolysaccharide pyrogens. In comparison with other monocyte activation tests it requires no cell preparation steps or cell culture facilities. The procedure takes 21–35 h to complete.
