Local Shwartzman reaction in the rat induced by endotoxin and ischemia: potential model for skin necrosis in meningococcemia.

The local Shwartzman reaction (LSR) is an inflammatory response in the skin that is considered a model for skin necrosis associated with meningococcemia. We tested the hypothesis that ischemia can act as the provocative agent to produce this response. In eight rats, bilateral inferior epigastric flaps were outlined. Within each flap, three injection sites were marked. Site 1 had 0.1 mL of endotoxin injected 24 h before surgery. The other two sites had either endotoxin or saline injected immediately before surgery. Both flaps were raised on their pedicle and one side rendered ischemic for 6 h and then reperfused. Animals were killed either 30 min or 48 h later and the tissue from each site examined. After 48 h of reperfusion, necrosis was grossly visible at the site of 24-h preischemia injection of endotoxin in three of four rats. No abnormalities were present at the other injection sites. Microscopically, all 24-h-delayed injection sites showed hemorrhage into all layers of the skin after both 30 min and 48 h of reperfusion. No hemorrhage was present at the other sites. These findings may serve as a potential model for the skin necrosis seen in meningococcemia.

The potential role of the Arthus and Shwartzman reactions in the pathogenesis of pneumonic pasteurellosis.

Pneumonic pasteurellosis (PP) is an economically important disease in cattle, sheep, and goats. Pasteurella haemolytica is commonly isolated from the severe fibrinopurulent pneumonia that characterize this respiratory syndrome. During infection, the bacteria produce leukotoxin (LKT) and lipopolysaccharide (LPS), both potent inducers of inflammation. Nonetheless, it has also been demonstrated that an exacerbated host's inflammatory response is responsible for the severe lung damage. Despite research in this field, the pathogenesis of PP is still incomplete. Two classical models of acute inflammatory response induced in laboratory animals, the Arthus and Shwartzman reactions, could explain the pathogenesis of the severe lung lesions that characterize PP.

Apoptotic cell death of vascular endothelial cells and renal tubular cells in the generalized Shwartzman reaction.

The participation of apoptotic cell in the generalized Shwartzman reaction was examined. The generalized Shwartzman reaction was induced in mice by two consecutive injections of lipopolysaccharide. Vascular endothelial cells in various organs of those mice were stained positively by the in situ specific labeling of fragmented DNA. Renal tubules were also stained focally. It was suggested that apoptotic cell death might participate in the development of vascular endothelial cell damage and acute tubular necrosis in the generalized Shwartzman reaction. Simultaneous administration of anti-gamma-interferon antibody in the preparative injection of lipopolysaccharide completely blocked apoptosis of vascular endothelial cells. Priming with recombinant gamma-interferon instead of lipopolysaccharide could produce apoptosis of vascular endothelial cells. It was suggested that gamma-interferon might play a critical role on sensitization of endothelial cells for apoptosis.

Guinea pigs prepared with various bacteria and their components to induce a necrotic reaction provoked with muramyldipeptide.

Guinea pigs were given a preparatory injection of heat-killed Mycobacterium tuberculosis in a water-in-mineral oil emulsion into the footpads. A provocative injection of muramyldipeptide given 3-8 weeks later into the flanks, caused severe inflammation, with hemorrhage and necrosis and necrosis at the footpads. In this study, we determined the features of the preparatory injection required to prepare the necrotic reaction. Most mycobacteria-related and Gram-negative bacteria were capable of preparing guinea pigs for the necrotic reaction upon provocative injection with muramyldipeptide, whereas Gram-positive bacteria did not. Boivin- and Morrison-type lipopolysaccharides, which have a high content of bacterial protein, induced the susceptibility, whereas Westphal-type lipopolysaccharide, which has a low level of the protein, did not. Moreover, the latter adjuvant-active lipopolysaccharide and muramyldipeptide together with ovalbumin also exerted the activity. The development of delayed-type hypersensitivity to the protein antigen seemed to be important for inducing the necrotic reaction. Mice, rats, rabbits and monkeys were injected in the same way as the guinea pigs. The necrotic reaction occurred in the flanks of the monkeys, but not in the other animals. A similar necrotic reaction also occurred in the flanks of guinea pigs given live BCG cells in phosphate-buffered saline as well as the heat-killed M. tuberculosis in water-in-mineral oil emulsion upon provocative injection with muramyldipeptide. These findings suggested that the induction is associated with the development of delayed-type hypersensitivity to the protein antigen administered in the preparatory injection [corrected].

Interleukin 12, interferon gamma, and tumor necrosis factor alpha are the key cytokines of the generalized Shwartzman reaction.

The Shwartzman reaction is elicited by two injections of lipopolysaccharide (LPS) in mice. The priming LPS injection is given in the footpad, whereas the lethal LPS challenge is given intravenously 24 h later. The injection of interferon gamma (IFN-gamma) or interleukin 12 (IL-12) instead of the LPS priming injection induced the lethal reaction in mice further challenged with LPS. Antibodies against IFN-gamma when given together with the priming agent, prevented the lethal reaction in mice primed with either LPS, IL-12, or IFN-gamma. Antibodies against IL-12, when given together with the priming agent, prevented the lethal reaction in mice primed with either LPS or IL-12 but not with IFN-gamma. These results strongly suggest that LPS induces the release of IL-12, that IL-12 induces the production of IFN-gamma, and that IFN-gamma is the cytokine that primes macrophages and other cell types. Upon LPS challenge, the lethal Shwartzman reaction is induced by a massive production of inflammatory cytokines that act on the target sites already sensitized by IFN-gamma. If mixtures of TNF and IL-1 or mixtures of TNF and IFN-gamma are used to challenge mice previously primed with IFN-gamma or IL-12, mortality is induced. In the same conditions, the individual cytokines or a mixture of IL-1 and IFN-gamma do not replace the LPS challenge. When the mice are primed with LPS, the combination of TNF, IL-1, and IFN-gamma induced only a partial mortality incidence suggesting that the involvement of other LPS-induced factors.

Biological activities of cell envelope fragments of the archaeobacterium Sulfolobus solfataricus: lethal toxicity, local hypersensitivity, pyrogenicity and spleen lymphocyte mitogenicity.

The sensitizing effect and the local and general toxicity related to membrane components of the archaeobacterium Sulfolobus solfataricus was studied. Cell envelope fragments were biologically active but this activity was lost upon separation of the lipid and protein components. The envelope fragments exerted lethal effects on mice sensitized with D-galactosamine that were prevented by pretreatment with anti-TNF-alpha serum. This lethal activity occurred in both LPS-responder (BALB/cByJ) and LPS-nonresponder (C3H/HeJ) mouse strains. In addition, Sulfolobus envelope fragments tested in rabbits caused a local Schwartzman reaction, and showed pyrogenic activity. In vitro, the envelope fragments that act on spleen lymphocytes of the LPS-responder (BALB/cByJ) and LPS-nonresponder (C3H/HeJ) mice caused an uptake of [3H]thymidine similar to that caused by concanavalin A. A similar toxic activity to that exerted by eubacteria is therefore exerted by this non-pathogenic archaeobacterium despite the difference in surface chemistry.

Fatal disseminated intravascular coagulation complicating dental extraction.

A case is reported of fatal disseminated intravascular coagulation occurring 8 h after routine extraction of wisdom teeth in a 24-year-old woman. Since all bacteriological specimens taken were sterile and no other precipitant was found, we believe this case represents an example of the generalised Shwartzman reaction to the local trauma of dental extraction leading to fatal initiation of the coagulation system.

The Shwartzman response: a model of ICAM-1 dependent vasculitis.

The local Shwartzman response was produced in rabbits by the intradermal injection of endotoxin, followed 24 h later by intravenous zymosan. Hemorrhagic lesions developed in the prepared skin sites. We quantitated the Shwartzman-induced hemorrhage with autologous 99mTc-erythrocytes. We show that the development of the Shwartzman response depends on both leukocyte membrane CD18 glycoprotein activity as well as the participation of intercellular adhesion molecule-1 (ICAM-1). We discuss the possibility that the common property shared by the agents capable of preparing the skin for the Shwartzman response is the ability to induce ICAM-1 expression.

[Scavenging effect of re-du-qing on free radicals].

The general Shwartzman reactions of rabbits were induced by intravenously injecting endotoxin twice with 24 hours interval. The lipid peroxides (LPO) in sera and liver homogenates of rabbits in normal saline group (12.26 +/- 0.84 n mol MDA/ml, 1.86 +/- 0.43 n mol MDA/mg protein respectively) were significantly higher than those of rabbits in normal control group (7.93 +/- 2.90, 1.31 +/- 0.22, both P less than 0.01), and LPO in sera and liver homogenates of rabbits in Re-Du-Qing group (6.55 +/- 2.97, 1.19 +/- 0.12) were evidently lower than those of rabbits in normal saline group (P less than 0.01), accessed to the LPO level of rabbits in normal control group. In in vitro experiment, LPO of mitochondria in Re-Du-Qing group (1.50 +/- 0.43 n mol MDA/mg protein) dramatically decreased, compared with that of endotoxin group (2.39 +/- 0.69, P less than 0.05) and of control group (2.23 +/- 0.75, P less than 0.05). The findings of both in vivo and in vitro experiments showed that Re-Du-Qing possesses scavenging effect on free radicals. In view of the detoxification mechanism of Re-Du-Qing, in addition to inhibiting bacteria and degrading. endotoxin, the scavenging effect of Re-Du-Qing on free radicals are also included.

Interferon gamma, a mediator of lethal lipopolysaccharide-induced Shwartzman-like shock reactions in mice.

The involvement of cytokines in the pathogenesis of a generalized, Shwartzman-like lethal inflammatory response to bacterial lipopolysaccharides (LPS) was studied by testing the ability of cytokines or neutralizing anticytokine antibodies to modify the course of the syndrome. The reaction was elicitable in non-SPF NMRI mice by two consecutive injections of S. marcescens LPS: a first injection in the footpad, followed after 24 h by an intravenous dose; the size and route of the preparatory LPS dose were found to be critical. Treatment with mAbs against IFN-gamma was found to completely prevent the reaction. Treatment with IFN-gamma on the other hand, rendered the mice more sensitive to elicitation of the reaction. In contrast, systemic administration of IFN-alpha/beta exerted a desensitizing effect. The role of endogenous cytokines in the pathogenesis of this generalized Shwartzman reaction was also documented by a study of the cytokine levels in the serum of the mice. In comparisons between mice given lethal and nonlethal induction schedules, a good correlation was found between mortality rates and height of IFN or TNF levels, but no correlation was seen with IL-6 levels. Also, in mice that were protected by anti-IFN-gamma antibody, serum IFN and TNF were undetectable, whereas IL-6 levels were as high as in unprotected mice. These data provide evidence that among the cytokines that govern the inflammatory response to LPS, endogenous IFN-gamma occupies a key position. These findings therefore also open perspectives for clinical application of IFN-gamma antagonists.

[The similarity of the biological effects from the parenteral administration of ascarid antigenic complexes and Salmonella typhi endotoxins]. / Skhodstvo biologicheskikh éffektov pri parenteral'nom vvedenii antigennykh kompleksov askarid i éndotoksinov briushnotifoznykh bakterii.

The experiment with rabbits showed that it was basically possible to develop local and generalized Shwartzman's phenomenon under the combined effect of ascaris antigens and typhoid bacterial endotoxins. Intracutaneous (0.2 ml.) or intravenous (0.1 ml/kg) sensitization of animals by ascaris antigens or microbe endotoxins after repeated intravenous crossover, intravenous injection of the antigens used to result in the development of classical local and generalized Shwartzman's phenomenon.

The role of cytokines in various animal models of inflammation.

Studies are reviewed in which the role of IFN-gamma in different models of inflammation in mice is examined: LPS-induced generalized Shwartzman reaction, experimental allergic encephalomyelitis (EAE) and experimental cerebral malaria (ECM). The particular role of the cytokine was studied by systemic administration and by blocking the endogenously produced cytokine by the use of neutralizing antibodies. IFN-gamma was found, depending on the model and circumstances, to exert an anti- or a pro-inflammatory effect. In the generalized Shwartzman reaction and ECM this cytokine has a disease promoting role. In EAE, on the contrary, endogenous as well as exogenous IFN-gamma exert a down-regulating effect.

Structural heterogeneity regarding local Shwartzman activity of lipid A.

The relation of chemical structure to local Shwartzman activity of lipid A preparations purified by thin-layer chromatography from five bacterial strains was examined. Two lipid A fractions from E. coli F515--Ec-A2 and Ec-A3--exhibited strong activity, similar to that of previous synthetic E. coli-type lipid A (compound 506 or LA-15-PP). The Ec-A3 fraction contained a component that appeared to be structurally identical to compound 506, and the main component of Ec-A2 fraction was structurally similar to compound 506 except that it carried a 3-hydroxytetradecanoyl group at the C-3' position of the backbone in place of a 3-tetradecanoyloxytetradecanoyl group. Free lipid A (12 C) and purified lipid A fractions, Ec-A2 (12 C) and Ec-A3 (12 C), respectively, obtained from bacteria grown at 12 C, exhibited activity comparable to Ec-A2 or Ec-A3. In these preparations, a large part of the 3-dodecanoyloxytetradecanoyl group might be replaced by 3-hexadecenoyloxytetradecanoyl group. Salmonella minnesota R595 free lipid A also contained at least two active lipid A components as seen in E. coli lipid A, but the third component corresponding to the synthetic Salmonella-type lipid A (compound 516 or LA-16-PP) exhibited low activity. A lipid A fraction, Cv-A4 from Chromobacterium violaceum IFO 12614, which was proposed to have two acyloxyacyl groups at the C-2 and C-2' positions with other acyl groups, exhibited weaker activity than the free lipid A or LPS. The purified lipid A fractions from Pseudomonas diminuta JCM 2788 and Pseudomonas vesicularis JCM 1477 contained an unusual backbone with 2,3-diamino-2,3-dideoxy-D-glucose disaccharide phosphomonoester, and these lipid A (Pd-A3 and Pv-A3) exhibited strong activity comparable to the E. coli lipid A. Thus, the present results show that the local Shwartzman reaction can be expressed by partly different lipid A structures in both hydrophilic backbone and fatty acyl residues; when they have the same backbone the potency varies markedly depending on the structure of the acyl residues.

Vasoactive agents and production of thrombosis during intravascular coagulation. 3. Comparative effects of catecholamines.

Epinephrine (E), isoproterenol (I), and dopamine (D) were compared with norepinephrine (N) for production of microthrombi during thrombin-induced disseminated intravascular coagulation (DIC) in rabbits. Only catecholamines acting on alpha-adrenoreceptors produced glomerular capillary thrombosis (GCT) typical of the generalized Shwartzman reaction (GSR). Epinephrine produced GCT three times (P less than 0.05) less severe than that produced by N, but beta-blockade with propranolol (P) rendered E equal to N in potency. I and D reduced fibrinogen consumption produced by thrombin. I (0.5-0.66 microgram/kg/min), as opposed to D, prevented the GSR produced by endotoxin in the pregnant rat and the cortisone-sensitized rabbit, and P increased the severity of the GSR in the pregnant rat. Alpha-adrenergic blockade with dibenzyline prevented the GSR produced by endotoxin in rats, whether pregnant, diabetic, or having a unilateral ureteral occlusion, and the classic reaction in rabbits, but not that produced in renal-hypertensive rats. Simultaneous alpha + beta stimulations by E triggered coronary and hepatic microthrombi, which were prevented by P. It is concluded that beta-adrenergic stimulation, as opposed to D-adrenergic stimulation, counterbalances alpha-adrenergic effects occurring in endotoxemia, which are required for production of the GSR in most models. These studies stress the risks and benefits of beta-blockade and provide additional evidence for the role of vasoactive agents and microcirculatory changes on selection of target organs for production of microthrombi during DIC.

Lipopolysaccharide-mediated injury to cultured human glomerular endothelial cells.

Lipopolysaccharide induced a dose-dependent detachment of human glomerular cells in vitro. The detachment occurred 24 hr after exposure to endotoxin. Human umbilical vein endothelial cells were not affected by more prolonged exposure or higher concentrations of lipopolysaccharide in the medium. The lipopolysaccharide effect was independent of complement components or leukocytes.