Interleukin 1-induced pathophysiology: induction of cytokines, development of histopathologic changes, and immunopharmacologic intervention

A randomized, placebo-controlled clinical trial evaluating of a mouthwash containing Sambucus williamsii var. coreana extract for prevention of gingivitits

The purpose of this study is to verify the clinical applicability by applying a mouthwash containing Sambucus williamsii var. coreana extract for preventing periodontal disease. A randomized, double-blind, placebo-controlled study was conducted on 64 patients, excluding those with insufficient data, who visited M dental clinic located in Busan, Korea. Thirty-two people were assigned respectively to the saline solution gargle group and the Sambucus williamsii var. coreana extract gargle group to conduct the O'Leary index, plaque index (PI), gingival index (GI), and subgingival plaques. For the homogeneity of the two groups, scaling was carried out one week before the experiment, and the participants were taught for oral care to conduct during the study period. SPSS 24.0 for Windows (IBM Corp., Armonk, NY, USA) was used to compare the saline solution gargle group and the Sambucus williamsii var. coreana extract gargle group as well as to analyze Baseline (before gargle application), Treatment (immediately after gargle application), and After 5 Days (5 days after gargle application). There was a significant difference in the O'Leary index, PI, GI and subgingival plaques after Treatment and After 5 days (p < 0.05). Also, the periodontal-related indexes improved as the application time increased in the Sambucus williamsii var. coreana extract gargle group. The antibacterial effect was also shown for gram-positive bacteria and gram-negative bacteria in subgingival plaques as the application time increased. The use of the mouthwash containing Sambucus williamsii var. coreana extract was found to be effective for oral periodontal-related indicators and bacteria causing periodontal disease. Therefore, using a mouthwash containing Sambucus williamsii var. coreana extract, a natural drug, will possibly maintain healthy periodontal health by inhibiting and preventing the progression of periodontal disease.

MHC/class-II-positive cells inhibit corticosterone of adrenal gland cells in experimental arthritis: a role for IL-1β, IL-18, and the inflammasome

In experimental arthritis, glucocorticoid secretion is inadequate relative to inflammation. We hypothesized that IL-1 is a key factor for inadequate glucocorticoid secretion in arthritic rats. Collagen type II—induced arthritis (CIA) in DA rats was the model to study effects of IL-1 on adrenal function. In the CIA model, an increase of intraadrenal MHCII-positive cells was observed. MHCII-positive cells or bone marrow-derived dendritic cells inhibited glucocorticoid secretion of adrenal gland cells. IL-1, but also IL-18 and the inflammasome were critical in glucocorticoid inhibition. Arthritic compared to control adrenal gland cells produced higher amounts of CXC chemokines from MHCII+ adrenal cells, particularly CINC-2, which is strongly dependent on presence of IL-1. In CIA, macrophages and/or dendritic cells inhibit glucocorticoid secretion via IL-1 in adrenal glands. These findings show that activated macrophages and/or dendritic cells inhibit glucocorticoid secretion in experimental arthritis and that IL-1β is a decisive factor.

TAKEDA-143242 increased survival via reduced cytokines in porcine peritonitis

TAKEDA-143242 (TAK-242) is a small molecule shown to inhibit lipopolysaccharide-induced intracellular signaling and inflammation. In vitro studies demonstrated that TAK-242 can prevent release of TNF-α, IL-1β, and IL-6 from activated macrophages of several species, including pigs. This study tested the hypothesis that TAK-242 would protect pigs from lethal gram-negative peritonitis via an anti-cytokine mechanism. A validated model of porcine gram-negative peritonitis, which employs chronically inplantated cardiac transducers and aortic and pulmonary artery catheters, was used. Pigs were pretreated with TAK-242 or its vehicle via a blinding procedure prior to intraperitoneal implantation of an LD(90) dose of E. coli 0111:B4 in a fibrin clot. Ten pigs were treated with TAK-242 and nine with its vehicle. All ten TAK-242 treated pigs survived, while three of the nine vehicle treated pigs survived (P = 0.01 χ(2) test). Pulmonary artery pressure increased markedly in vehicle pigs, and this elevation was significantly (two-way ANOVA) obviated in TAK-242 treated group. Circulating levels of cytokines in vehicle treated pigs showed increased expression (3930 ± 1770 at 1 h, 1007 ± 400 TNF-α at 2 h; 719 ± 308 of IL-1β at 2-6 h; 33000 ± 1000 of IL-6 at 2-4 h [pg/mL, mean ± SEM]). Peak circulating levels of these cytokines were significantly reduced by pretreatment with TAK-242 (<25 pg/mL TNF-α ; <100 pg/mL IL-1β; 0-1700 pg/mL IL-6, peak values). This study found that pretreatment with TAK-242 yielded significantly positive survival benefit in a lethal sepsis model that was associated with improved cardiovascular status and suppressed cytokine release.

Interleukin-6 expression after infectious bronchitis virus infection in chickens

Viral infections in chickens pose a major health threat to the poultry industry. Infectious bronchitis virus (IBV) usually causes respiratory disease; however, the disease severity is influenced by the genotype of the chicken and the IBV strain involved. Nephropathogenic strains of IBV, such as the Australian T strain, can cause high mortalities due to kidney failure characterized by mononuclear cell infiltration and inflammation. In a previous study, a line of specific pathogen-free chickens, the S-line, was shown to be susceptible to high mortalities from IBV infection. The cause of these high mortalities is unknown but it is suspected that differential cytokine expression may play a role. With this in mind, we decided to study the role of the proinflammatory cytokine interleukin (IL)-6 during infection to determine its contribution to nephritis and influence on disease susceptibility. To investigate this, we infected the susceptible S-line and the more disease-resilient HWL line with the T strain of IBV and measured their cytokine response levels. In both lines of birds, IL-6 mRNA levels were elevated in the kidneys at 4 d postinfection. However, in S-line chickens, these levels were 20 times higher than those in the HWL chickens. In addition, S-line birds also showed three times higher serum IL-6 levels than HWL birds after IBV infection. These findings suggest that IL-6 may play a role in IBV-induced nephritis and may open an avenue to develop alternative strategies, such as the use of antiinflammatory cytokines, to overcome the nephropathogenic effects of IBV.

Therapeutic effects of TAK-242, a novel selective Toll-like receptor 4 signal transduction inhibitor, in mouse endotoxin shock model

Ethyl (6R)-6-[N-(2-chloro-4-fluorophenyl)sulfamoyl]cyclohex-1-ene-1-carboxylate (TAK-242), a novel small molecule that selectively inhibits Toll-like receptor 4-mediated signaling, inhibits various kinds of inflammatory mediators such as nitric oxide (NO), tumor necrosis factor (TNF)-alpha, interleukin (IL)-1, IL-6, IL-10, macrophage inhibitory protein (MIP)-2 and prostaglandin E2 from lipopolysaccharide (LPS)-stimulated macrophages. The effects of TAK-242 were evaluated in a mouse model of endotoxin shock. Intravenous administration of TAK-242 to mice 1 h before LPS challenge dose-dependently inhibited LPS-induced increases in serum levels of TNF-alpha, IL-1beta, IL-6, IL-10, MIP-2, and NO metabolites. TAK-242 protected mice from LPS-induced lethality in a similar dose-dependent manner, and rescued 100% of mice at a dose of 1 mg/kg. Interestingly, TAK-242 worked quickly, and showed beneficial effects even when administered after LPS challenge. Even though increases in serum levels of IL-6 and hypothermia were already evident 2 h after LPS challenge, TAK-242 administration inhibited further increase in IL-6 levels and decrease in body temperature. LPS-induced increases in serum levels of organ dysfunction markers, such as alanine aminotransferase, total bilirubin, and blood urea nitrogen, were also significantly suppressed by post-treatment as well as pre-treatment. Furthermore, administration of 3 mg/kg TAK-242 significantly increased survival of mice, even when given 4 h after LPS challenge. These results suggest that TAK-242 protects mice against LPS-induced lethality by inhibiting production of multiple cytokines and NO. TAK-242 has a quick onset of action and provides significant benefits by post-treatment, suggesting that it may be a promising drug candidate for the treatment of sepsis.

Smoking modulates interleukin-6:interleukin-10 and RANKL:osteoprotegerin ratios in the periodontal tissues

BACKGROUND AND OBJECTIVE

This study evaluated the effect of smoking on the gene expression of interleukin-1alpha, -1ra, -6, -8 and -10, tumor necrosis factor-alpha, matrix metalloproteinase (MMP)-2 and -8, receptor activator of NF-kappaB ligand (RANKL) and osteoprotegerin, in sites with periodontitis.

MATERIAL AND METHODS

Gingival biopsies were divided into three groups: the healthy group (periodontally healthy subjects; n=10); the periodontitis group [subjects with severe chronic periodontitis who never smoked (probing depth>or=7 mm) (n=25)]; and the smoking group (subjects diagnosed with severe chronic periodontitis who smoked>or=1 pack per day for at least 10 years; n=25). Gene and protein expressions were analyzed by quantitative polymerase chain reaction and enzyme-linked immunosorbent assay, respectively.

RESULTS

Data analysis demonstrated that, except for MMP-8 and osteoprotegerin, the levels of all factors were increased by inflammation (p<0.001). The levels of interleukin-1alpha, -1ra, -6 and -8, and RANKL, were higher in smokers with periodontitis compared with controls, whereas the levels of interleukin-10, MMP-8 and osteoprotegerin were lower (p<0.001). Smoking lowered the levels of interleukin-1alpha, -8, -10, tumor necrosis factor-alpha, MMP-8 and osteoprotegerin, and increased the levels of interleukin-6 and -1ra in sites with a comparable type of periodontitis (p<0.001).

CONCLUSION

In conclusion, smoking modulates gene expression in the periodontium, and the influence of smoking on periodontal disease may involve effects of interleukin-6:interleukin-10 and RANKL:osteoprotegerin ratios.

Graded Doses of Recombinant Interleukin-1β Induce Generalized Osteopenia in Rats without Altering Skeletal Growth and Joint Integrity

BACKGROUND

Whereas a primary role of interleukin-1beta (IL-1beta) in local bone remodelling and articular inflammation has been well established, the effect of prolonged systemic administration of this cytokine on total skeletal Ca, somatic growth and joint tissue has not yet been investigated.

METHODS

Five groups of 14 rats each, aged 7-8 weeks, had miniosmotic pumps (Alzet 200 microl) implanted and primed to release 100, 200, 500, 1,000 and 2,000 ng/kg/24 h of human recombinant IL-1beta (rIL-1beta) daily for 14 days. On days 0 and 14 total skeletal mineral content (BMC) was assessed by means of X-ray absorptiometry and vertebral and tibial growth was measured by computer-assisted radiometry. On the same days, blood was drawn and analyzed for rat growth hormone (rGH), insulin-like growth factor (IGF-1), and osteocalcin. Also 24-hour urine was collected for d-pyridinoline (dpd) determinations. Hind- and forepaw diameter as a parameter of joint inflammation was assessed using a micrometric calliper. Subsequently the animals were sacrificed and one tibia dissected for measurement of trabecular volume by computerized histomorphometry.

RESULTS

BMC decreased in a dose-dependent manner reaching significance at 1,000 and 2,000 ng/kg (p < 0.03 and 0.04) in close correlation with tibial trabecular volumes (r = 0.84; p < 0.02). Normal vertebral and tibial growth was recorded at all dosages. There was no evidence of joint involvement. Blood rGH and IGF-1 remained normal as did osteocalcin, the latter reflecting lack of osteoblast activation. In contrast dpd increased in a dose-dependent manner indicating enhanced bone matrix turnover.

CONCLUSION

It is concluded that graded infusions of supraphysiological doses of rIL-1beta capable of inducing osteopenia did not affect skeletal growth in the absence of articular reaction. This is in contrast with the experience recorded in experimental arthritis in which growth retardation, in addition to osteopenia, may be caused by factors other than circulating IL-1beta.

Tumor necrosis factor alpha reduces butyrate oxidation in vitro in human colonic mucosa: a link from inflammatory process to mucosal damage?

BACKGROUND

Butyrate produced by colonic bacterial fermentation is the main fuel for colonocytes, glucose being an alternative fuel. During inflammatory bowel disease, butyrate oxidation by colonocytes is impaired, and increased production of proinflammatory cytokines is detected in the colonic mucosa. We hypothesized that proinflammatory cytokines might reduce butyrate oxidation, and we assessed the in vitro effects of 3 proinflammatory cytokines on butyrate and glucose oxidation in colonic mucosa.

METHODS

Colonic biopsies were obtained from normal mucosa in 42 patients who underwent a colonoscopy. Biopsies were incubated in RPMI 1640 with [1-14C]-butyrate or [U-14C]-glucose with or without 1 of the 3 following proinflammatory cytokines: tumor necrosis factor alpha (TNFalpha), interleukin (IL)-1beta, and IL-6. For each cytokine, 4 different concentrations were tested in 8 subjects. Concentrations overlapped those commonly found in inflamed mucosa and had no cytotoxicity as assessed in preliminary experiments using both the trypan blue exclusion test and lactate dehydrogenase release. Production of 14CO2 (picomoles per microgram dry weight per hour) was measured after a 2-hour incubation and expressed as a percentage of the control [14C]-substrate oxidation without cytokines.

RESULTS

Whereas glucose oxidation was not affected, butyrate oxidation was reduced significantly (P < 0.05) by TNFalpha at concentrations of 100 (-26 +/- 6%), 1000 (-32 +/- 7%), and 5000 pg/mL (-34 +/- 5%). IL-1beta (0, 500, 5000, and 25,000 pg/mL) and IL-6 (0, 100, 1000, and 5000 pg/mL) did not affect either substrate oxidation.

CONCLUSIONS

TNFalpha at concentrations found in inflamed mucosa reduces butyrate oxidation in vitro in mucosa from healthy controls. This result is not caused by a cytotoxic effect of TNFalpha and is not balanced by an increased oxidation of glucose. Reduced butyrate oxidation results in a decreased energy supply to colonocytes and may explain, in part, mucosal damage occurring during attacks of inflammatory bowel disease.

Further characterization of high mobility group box 1 (HMGB1) as a proinflammatory cytokine: central nervous system effects

High mobility group box 1 (HMGB1), an abundant, highly conserved cellular protein, is widely known as a nuclear DNA-binding protein. HMGB1 has been recently implicated as a proinflammatory cytokine because of its role as a late mediator of endotoxin lethality and ability to stimulate release of proinflammatory cytokines from monocytes. Production of central cytokines is a critical step in the pathway by which endotoxin and peripheral proinflammatory cytokines, including interleukin-1beta (IL-1) and tumor necrosis factor-alpha (TNF), produce sickness behaviors and fever. Intracerebroventricular (ICV) administration of HMGB1 has been shown to increase TNF expression in mouse brain and induce aphagia and taste aversion. Here we show that ICV injections of HMGB1 induce fever and hypothalamic IL-1 in rats. Furthermore, we show that intrathecal administration of HMGB1 produces mechanical allodynia (lowering of the response threshold to calibrated stimuli). Finally, while endotoxin (lipopolysaccharide, LPS) administration elevates IL-1 and TNF mRNA in various brain regions, HMGB1 mRNA is unchanged. It remains possible that HMGB1 protein is released in brain in response to LPS. Nonetheless, these data suggest that HMGB1 may play a role as an endogenous pyrogen and support the concept that HMGB1 has proinflammatory characteristics within the central nervous system.

Pathways to acute humoral rejection

Acute humoral rejection, also known as acute vascular rejection, is a devastating condition of organ transplants and a major barrier to clinical application of organ xenotransplantation. Although initiation of acute humoral or vascular rejection is generally linked to the action of antibodies and complement on the graft, other factors such as ischemia, platelets, T cells, natural killer cells, and macrophages have also been implicated. Central to any understanding of the pathogenesis of acute humoral rejection, and to developing means of preventing it, is to know whether these factors injure the graft independently or through one or few pathways. We addressed this question by examining early events in a severe model of vascular rejection in which guinea pig hearts transplanted heterotopically into rats treated with cobra venom factor (CVF) develop disease over 72 hours. The early steps in acute vascular rejection were associated with expression of a set of inflammatory genes, which appeared to be controlled by availability of interleukin (IL)-1. Interruption of IL-1 signaling by IL-1 receptor antagonist (IL-1ra) averted expression of these genes and early tissue changes, including coagulation and influx of inflammatory cells. These findings suggest IL-1 plays an important role in initiation of acute humoral rejection.

Innate immune sensing and its roots: the story of endotoxin

How does the host sense pathogens? Our present concepts grew directly from longstanding efforts to understand infectious disease: how microbes harm the host, what molecules are sensed and, ultimately, the nature of the receptors that the host uses. The discovery of the host sensors--the Toll-like receptors--was rooted in chemical, biological and genetic analyses that centred on a bacterial poison, termed endotoxin.

Science review: key inflammatory and stress pathways in critical illness - the central role of the Toll-like receptors

A pure reductionist approach can sometimes be used to solve an exceptionally complicated biologic problem, and sepsis is nothing if not complicated. A serious infection promptly leads to changes in many aspects of host physiology, including alterations in circulation, metabolism, renal, hepatic, and neuroendocrine function; all of these changes happen at once, and each influences one another. It is difficult to tease apart a problem of this sort, if only because the systems affected are so profoundly interactive. The key to understanding sepsis, insofar as we do understand it at present, was found in the use of genetic tools to study the very earliest events that take place at the interface of the pathogen and the host. The continued application of both forward and reverse genetic methods, in both mammals and insects, is steadily revealing the central biochemical events that occur during infection.

Periodontitis and diabetes interrelationships: role of inflammation

Diabetes mellitus is a systemic disease with several major complications affecting both the quality and length of life. One of these complications is periodontal disease (periodontitis). Periodontitis is much more than a localized oral infection. Recent data indicate that periodontitis may cause changes in systemic physiology. The interrelationships between periodontitis and diabetes provide an example of systemic disease predisposing to oral infection, and once that infection is established, the oral infection exacerbates systemic disease. In this case, it may also be possible for the oral infection to predispose to systemic disease. In order to understand the cellular/molecular mechanisms responsible for such a cyclical association, one must identify common physiological changes associated with diabetes and periodontitis that produce a synergy when the conditions coexist. A potential mechanistic link involves the broad axis of inflammation, specifically immune cell phenotype, serum lipid levels, and tissue homeostasis. Diabetes-induced changes in immune cell function produce an inflammatory immune cell phenotype (upregulation of proinflammatory cytokines from monocytes/polymorphonuclear leukocytes and downregulation of growth factors from macrophages). This predisposes to chronic inflammation, progressive tissue breakdown, and diminished tissue repair capacity. Periodontal tissues frequently manifest these changes because they are constantly wounded by substances emanating from bacterial biofilms. Diabetic patients are prone to elevated low density lipoprotein cholesterol and triglycerides (LDL/TRG) even when blood glucose levels are well controlled. This is significant, as recent studies demonstrate that hyperlipidemia may be one of the factors associated with diabetes-induced immune cell alterations. Recent human studies have established a relationship between high serum lipid levels and periodontitis. Some evidence now suggests that periodontitis itself may lead to elevated LDL/TRG. Periodontitis-induced bacteremia/endotoxemia has been shown to cause elevations of serum proinflammatory cytokines such as interleukin-1 beta (IL-1 beta) and tumor necrosis factor-alpha (TNF-alpha), which have been demonstrated to produce alterations in lipid metabolism leading to hyperlipidemia. Within this context, periodontitis may contribute to elevated proinflammatory cytokines/serum lipids and potentially to systemic disease arising from chronic hyperlipidemia and/or increased inflammatory mediators. These cytokines can produce an insulin resistance syndrome similar to that observed in diabetes and initiate destruction of pancreatic beta cells leading to development of diabetes. Thus, there is potential for periodontitis to exacerbate diabetes-induced hyperlipidemia, immune cell alterations, and diminished tissue repair capacity. It may also be possible for chronic periodontitis to induce diabetes.

Protection against lipopolysaccharide-induced death by fluoroquinolones

Because fluoroquinolones have an immunomodulatory effect on cytokine production by lipopolysaccharide (LPS)-treated human monocytes, we examined the effect of fluoroquinolones on the survival of mice injected with a lethal dose of LPS. Trovafloxacin (100 mg/kg), ciprofloxacin (250 mg/kg), and tosufloxacin (100 mg/kg) protected 75% (P = 0.0001), 25% (P = 0.002), and 50% (P = 0.002), respectively, of mice against death. The fluoroquinolones significantly reduced serum levels of interleukin-6 and tumor necrosis factor alpha in LPS-treated mice. The protective effects of fluoroquinolones in LPS-induced shock in mice may also occur in humans.

Tissue factor pathway of coagulation in sepsis

OBJECTIVE

To review the role of the tissue factor pathway of coagulation in experimental sepsis.

DATA SOURCES

Studies published in biomedical journals.

STUDY SELECTION

Studies on the role of the tissue factor pathway in animal or human models for sepsis.

DATA EXTRACTION AND SYNTHESIS

Variables reflecting tissue factor pathway activation in the various models are discussed; the effects of administration of tissue factor pathway inhibitors on these and inflammatory variables, as well as on the course and outcome, are analyzed.

CONCLUSION

Activation of coagulation during experimental sepsis occurs mainly, if not exclusively, via the tissue factor pathway; inhibitors of this pathway improve mortality, presumably by a combined attenuating effect on coagulative and inflammatory responses.

Nitric oxide and intestinal barrier failure

The systemic inflammatory response syndrome (SIRS) is a leading cause of morbidity and mortality in adults and children. Various proinflammatory mediators have been implicated in the pathogenesis of SIRS; however, their mechanisms of action are poorly defined. Recent evidence suggests that nitric oxide (NO) plays a regulatory role in gut barrier function. Sustained upregulation of NO production in the intestine can lead to intestinal epithelial injury through the formation of peroxynitrite. Peroxynitrite can nitrate mitochondrial proteins and inhibit cellular respiration. The resultant changes in mitochondrial function lead to activation of the caspase cascade, subsequent DNA fragmentation, and enterocyte apoptosis. Enterocyte apoptosis results in a transient "bare area" in the intestinal epithelium where bacteria can attach and then penetrate the lamina propria. Bacteria that successfully escape the immune system may in turn incite a systemic inflammatory response.

Western blot analysis of bile or intestinal fluid from patients with septic shock or systemic inflammatory response syndrome, using antibodies to TNF-alpha, IL-1 alpha and IL-1 beta

Septic shock or systemic inflammatory response syndrome (SIRS) often develops in patients following burns, traumatic injury, surgery or biliary obstruction. Although the inflammatory cytokines TNF-alpha and IL-1 have been strongly implicated in the development of these syndromes, treatment of patients by the systemic administration of inhibitors of TNF-alpha or IL-1 has shown limited effectiveness. Recent reports suggest that septic shock may be perpetuated by inflammatory cytokines secreted by the liver in response to bacterial translocation resulting from cytokine-induced gastrointestinal damage. The present study sought to demonstrate the presence of high levels of inflammatory cytokines in the bile or small intestine of patients suffering from septic shock or SIRS, with a view to the development of strategies for the reduction of gastrointestinal damage through intraduodenal administration of cytokine inhibitors. Western blot analysis of human bile or intestinal fluid using anti-TNF-alpha antibodies resulted in the detection of a number of bands in samples from patients with septic shock or SIRS. However, these proteins differed antigenically from human recombinant TNF-alpha (rTNF-alpha) and showed no activity in a biological assay for TNF-alpha. Antibodies to IL-1 alpha and IL-1 beta detected several strong bands, some of which appeared to be identical to recombinant IL-1 alpha and IL-1 beta. It is concluded that proteins resembling several known inflammatory cytokines are present in the bile and intestine of septic shock patients, but it is suggested that further work is required to determine the nature and function of these molecules.

Role of tumor necrosis factor alpha in induction of murine CD14 gene expression by lipopolysaccharide

We previously demonstrated CD14 gene expression in myeloid and epithelial cells of the mouse and showed that expression of the CD14 gene in both is modulated by lipopolysaccharide (LPS). Here we test the hypothesis that the induction of CD14 in these cells is an indirect effect of LPS, one mediated by tumor necrosis factor alpha (TNF-alpha). TNF-alpha induced a transient increase in levels of CD14 in plasma with a peak at 6 to 8 h, and this increase in levels of CD14 antigen in plasma was accompanied by increased levels of CD14 mRNA in lung, liver, and kidney. Moreover, in situ hybridization studies revealed that CD14 mRNA was induced in both myeloid cells and epithelial cells, the same cells that respond to LPS. Pretreatment of mice with anti-TNF antiserum reduced the LPS-mediated increase in levels of CD14 in plasma and significantly reduced the level of induction of CD14 mRNA in selected epithelial cells in the kidney and liver. The antiserum did not appear to block LPS-mediated induction in myeloid cells in the tissues examined. In C3H/HeJ mice, the epithelial response to LPS was markedly attenuated whereas the response to TNF-alpha was normal. Thus, regulation of CD14 gene expression by LPS differs in epithelial and myeloid cells, with the epithelial responses in kidney and liver being mediated, in part, by TNF-alpha.

Serum levels of tumour necrosis factor alpha and other cytokines do not correlate with weight loss and anorexia in cancer patients

Cancer anorexia-cachexia syndrome (CACS), which is characterized by progressive weight loss (WL) and anorexia (A), is present in 50% of advanced cancer patients and in 80% of terminally ill cancer patients. One of the most controversial aspects of CACS is its oetiopathogenesis; experimental studies have identified certain cytokines [Tumour necrosis factor alpha (TNF-alpha), interleukin 1 (IL-1), interleukin 6 (IL-6), and gamma interferon (gamma-IFN)] as possible co-factors in the onset of the syndrome. The aim of our study was to investigate the correlation between serum levels of circulating cytokines and severity of CACS. The following series of parameters was identified in 61 patients with advanced and terminal cancer: stage of disease; Karnofsky performance status (KPS) and clinical symptoms; biohumoral, anthropometric and immunological situation; level of circulating cytokines. All these parameters were evaluated for a possible link with WL/A. Our data do not show any significant correlation between circulating cytokines and WL/A. A direct correlation was identified between WL/A and nausea (P = 0.03 and P < 0.001, respectively) whereas inverse correlations were observed for both factors as regards arm circumference (P < 0.001 for both), wrist circumference (P < 0.001 for both), KPS (P < 0.001 and P = 0.003, respectively) and creatinine (P = 0.005 and P = 0.03, respectively). Other biochemical factors, such as haemoglobin, haematocrit, glycaemia, prealbumin, sodium and chlorine were also correlated with at least one of two clinical parameters in question. Unexpected results were seen in the increases in CD20 and CD4 and in the CD4/CD8 ratio. Serum levels of these cytokines do not, therefore, appear to be critical in the onset of CACS. On the contrary, our findings confirmed the clinico-laboratory picture that is characteristic of CACS. If we consider the possibility that CACS is provoked by an aspecific response of the host's defence mechanisms against prolonged neoplastic attack, the increase in CD4 (helper lymphocytes) could be linked to the persistent response.

Multiple cytokines and acute inflammation raise mouse leptin levels: potential role in inflammatory anorexia

Several inflammatory cytokines, most notably tumor necrosis factor (TNF) and IL-1, induce anorexia and loss of lean body mass, common manifestations of acute and chronic inflammatory conditions. In C57BL/6 female mice, the administration of TNF, IL-1, and, to a lesser extent, leukemia inhibitory factor (LIF), produced a prompt and dose-dependent increase in serum leptin levels and leptin mRNA expression in fat. IL-10, IL-4, ciliary neurotrophic factor, and IL-2, cytokines not known to induce anorexia or decrease food intake, had no effect on leptin gene expression or serum leptin levels. After administration of Escherichia coli lipopolysaccharide (LPS), leptin gene expression and leptin levels were increased. These findings suggest that leptin levels may be one mechanism by which anorexia is induced during acute inflammatory conditions.

Combined treatment of IL-1 alpha and TNF-alpha potentiates the antitumour effect of hyperthermia

Vasoactive cytokines, such as IL-1 alpha and TNF-alpha, modulate the homeostatic state at the endothelial surface and cause various types of pathological damage in vascular systems. We investigated the potential therapeutic effects of IL-1 alpha and TNF-alpha in combination with hyperthermia on SCK tumours grown in the legs of A/J mice. We first determined the effect of cytokines on tumour blood perfusion with the (86)Rb uptake method. When the host mice were given an i.p. injection of 25 mu g/kg IL-1 alpha or 50 mu g/kg TNF-alpha, the tumour blood perfusion markedly declined to 46 and 82% of control, respectively. The combination of IL-1 alpha and TNF-alpha reduced the 86Rb uptake to 41% bf control. Hyperthermia at 42.5 degrees C for 1 h reduced the tumour blood flow to 71% of control. The tumour blood perfusion decreased further to 20% of control when the tumours were heated for 1 h at 42.5 degrees C starting 4h after the injection of both IL-1 alpha and TNF-alpha. The changes in clonogenic cell numbers in SCK tumours, as determined by the in vivo-in vitro assay, following various treatments was also investigated. At 4 h after an i.p. injection of 25 mu g/kg IL-1 alpha or 50 mu g/kg TNF-alpha, the clonogenicity of SCK tumours significantly decreased to 29 or 37% of control, respectively. Heating at 42.5 degrees C for 1 h caused a decline in the clonogenic cell number to 30% of control. When both IL-1 alpha and TNF-alpha were given and tumours were heated 4h later at 42.5 degrees C for 1 h, the clonogenic cell number markedly declined to 0.4% of control. The time needed for control tumours to reach 4 x their initial volume was about 3 days, and treatment with IL-1 alpha or hyperthermia alone induced a tumour delay growth by about 1 day. The combined injection of IL-1 alpha and TNF-alpha followed by a heating at 42.5 degrees C for 1 h delayed the tumour growth by 6 days. The results in this study suggest that prior impairment of blood circulation by the combined treatment of IL-1 alpha and TNF-alpha potentiates hyperthermic damage in tumours.

Monitoring of immunotherapy with cytokines or monoclonal antibodies

Recombinant cytokines and monoclonal antibodies (mAbs) are increasingly used in the treatment of a number of human diseases. Monitoring of the clinical efficacy of these agents requires specific clinical and laboratory measurements. A number of these novel therapies share common side effects, ranging from fever, headache and general malaise to hypotension, the development of edema leading to the vascular leak syndrome, the occurrence of thromboembolic processes and, in severe cases, organ dysfunction. As an example of the pathogenesis of these side effects, recent data are presented which were obtained in patients receiving immunotherapy with high doses of the cytokine interleukin-2 as an anti-cancer treatment.

Modulation of human polymorphonuclear leukocyte chemotaxis and superoxide anion production by Pseudomonas aeruginosa exoproducts, IL-1 beta and piroxicam

Whereas addition of 200 ng ml-1 exotoxin A (exoA) did not modify PMNL chemotaxis, 20 U ml-1 human recombinant interleukin-1 beta (hrIL-1 beta) primed polymorphonuclear leukocytes (PMNL) for migration towards Pseudomonas aeruginosa peptide chemotactins (PAPCs). Piroxicam (100 micrograms ml-1), a non-steroidal anti-inflammatory agent (NSAIA), inhibited PMNL chemotaxis and abolished the priming effect of hrIL-1 beta. Both PAPCs and exoA induced PMNL superoxide anion production, but neither hrIL-1 beta nor piroxicam modified significantly PMNL superoxide anion production induced by PAPCs. The fact that hrIL-1 beta can prime PMNL for chemotaxis towards PAPCs and that piroxicam can abolish activation by primed PMNL are findings relevant to the pharmacological control of lung tissue damage during P. aeruginosa pneumonia.

The role of cytokines in hemolytic transfusion reactions

Experimental evidence is accumulating to support a central role for cytokines in the pathophysiology of hemolytic transfusion reactions. The production of tumor necrosis factor, interleukin-8, and monocyte chemoattractant protein occurs in whole blood in response to ABO incompatible red cells, a model of acute hemolytic transfusion reactions. Peripheral blood mononuclear cells may produce interleukin-1 beta, tumor necrosis factor, interleukin-8, monocyte chemoattractant protein, and interleukin-1 receptor antagonist in response to IgG-coated red cells, a model of delayed hemolytic transfusion reactions. Cultured umbilical vein endothelial cells respond to conditioned plasma from ABO-incompatibility reactions by expressing the procoagulant tissue factor and the leukocyte adhesion molecules ELAM-1 and ICAM-1. These in vitro endothelial cell responses can be inhibited by neutralizing antibodies to tumor necrosis factor, suggesting that TNF may have a central role in intravascular coagulation and end-organ injury that may occur in acute hemolytic transfusion reactions.

Immunomodulator therapy in inflammatory bowel disease

The introduction of immunomodulator therapy in the treatment of patients with inflammatory bowel disease (IBD) has provided an important tool in modifying the mucosal immune system thought to be important in the pathogenesis of IBD. Currently available immunomodulating agents include azathioprine, 6-mercaptopurine, cyclosporin, and methotrexate. Recent clinical trials have demonstrated that these agents have an important therapeutic role in the treatment of patients who are either refractory or intolerant to traditional medical therapy. They are useful in the induction and maintenance of remission for both ulcerative colitis and Crohn's disease. However, these agents have significant toxicities and limited efficacy. In addition, potential risks of malignancy and infection limit their indiscriminate use. Thus, with the better understanding of the molecular basis of mucosal immunity, innovative immune-modifying therapies, such as antagonists of cytokines and inhibitors of T-cell activation, are being developed. It is likely that these exciting developments will soon result in specific immune modulating therapy with improved efficacy and reduced toxicity in the treatment of patients with IBD.

Biological response modifiers and infectious diseases: actual and potential therapeutic agents

Biological response modifiers (BRMs) are agents which can modify the immune response to cancer or invasion of the organism by infectious agents. An explosive appearance of new BRMs has resulted from the development of recombinant gene technology and the availability of monoclonal antibodies. Colony-stimulating factors first became available for the prevention of neutropenia but may also have a role in the treatment of infections. Interleukin-1 is being tested as a modular of hematopoiesis and may be useful as a helper factor for T- and B-cell function. Immunoglobulins are being used against viral and bacterial infections while interferons can prevent viral upper respiratory infections and suppress or irradicate some viral hepatitides. Other BRMs which show promise include chemical agents and traditional herbal medicines.

Cytokine mediators of septic infections in the normal and granulocytopenic host

Cytokines presently known to be involved in systemic bacterial infection are tumour-necrosis factor (TNF), interleukin (IL)-1, IL-6, IL-8 and interferon-gamma (IFN-gamma) and the counterregulatory molecules soluble TNF receptor (sTNFR) and IL-1 receptor antagonist (IL-1 Ra). In animal models TNF, IL-1 and IFN-gamma mediate organ damage, low blood pressure and fatality, whereas IL-6 is involved in infection-related manifestations, like the production of acute-phase protein and fever, and IL-8 is chemotactic to granulocytes. TNF and IL-1 increase expression of adhesion molecules on endothelial cells and influence a number of components of the haemostatic system in favour of coagulation. The presence of cytokines in the circulation is characterized by sequential releases of TNF, IL-1 and IL-6/IL-8; however, many variations of this pattern exist during human infection. In experiments as well as in human infection TNF, IL-1, IL-6, IL-8 and IFN-gamma have been detected, and levels of TNF, IL-6 and IL-8 have been found to be associated with the severity of the disease. Collectively, TNF, IL-1 and IFN-gamma emerge as mediators of systemic infection and septic shock whereas IL-6 and IL-8 are related to other manifestations of infection. Counteracting molecules like sTNFR are released after somewhat of a delay following TNF and IL-1Ra is released concomitantly with IL-1. Probably these factors modulate the cytokine effect although their true potency in natural infection has yet to be clarified. In granulocytopenic infections TNF, IL-1, IL-6 and IL-8 can be detected in serum, and levels of TNF and IL-6 are even higher than in the normal situation in experimental animals. Antibodies to TNF inhibit bacteria-induced fatality in granulocytopenic mice. Altogether, few data related to the granulocytopenic situation are available. However, it is reasonable to believe that the altered development of granulocytopenic infections is due to changes in the cellular constitution and not to changes in cytokine production.

Alterations in mononuclear cell tumour necrosis factor-alpha (TNF-alpha) response in patients on long term cuprophane haemodialysis

We have investigated TNF-alpha secretory response of peripheral blood mononuclear cells (PBMC) from 13 uraemic patients undergoing regular haemodialysis with cuprophane membrane (CM). Sixteen healthy subjects and five uraemic patients under conservative therapy were also studied as controls. Cells of haemodialysis patients exhibited increased TNF-alpha release in vitro in the absence of activating stimuli other than culture conditions, as compared with normal and uraemic controls. In contrast to normal cells, this spontaneous secretion of TNF-alpha from dialysis PBMC could not be significantly reduced by addition of polymyxin B to culture medium, thus indicating its independence of trace amount of lipopolysaccharide (LPS) present in the medium as contaminant. Furthermore, predialysis PBMC were considerably more sensitive to stimulation with 10(7) pg/ml of LPS under in vitro culture conditions than normal and uraemic controls. To elucidate a role of direct contact with CM in stimulation of TNF-alpha release from monocytes, PBMC were cultured on CM in vitro. Contact with CM stimulated TNF-alpha secretion from PBMC above the level of cells cultured on tissue culture plastic. This response persisted with time in culture in contrast to a transient LPS-induced TNF-alpha release. Furthermore, PBMC stimulated by contact with CM for 2 days did not lose the capacity to secrete TNF-alpha in response to a subsequent LPS stimulation, while a 2-day treatment of cells with LPS was followed by LPS refractory state. Therefore, direct contact with CM induces in PBMC a long-lasting TNF-alpha response which is not down-regulated by the acquisition of refractoriness in a manner similar to that which occurs in the case of LPS stimulation. These in vitro findings provide a possible explanation of the observation that predialysis PBMC exhibit elevated TNF-alpha secretory capacity.

Effects of interleukin-6 on cytochrome P450-dependent mixed-function oxidases in the rat

Intravenous treatment of male rats with recombinant human interleukin-6 (rhIL6) at 50, 100 and 200 micrograms/kg (corresponding to 4, 8 and 16 x 10(4) U/animal, respectively) reduced the activities of hepatic microsomal cytochrome P450-dependent monoxygenases to varying degrees. Ethylmorphine-N-demethylase activity fell to 53% of control values, an effect similar to that induced by 2.5 mg/kg Escherichia coli lipopolysaccharide (LPS). Ethoxycoumarin-O-deethylase activity was also sensitive to inhibition, whereas IL6 had little effect on the activities of other P450-dependent enzymes, including ethoxyresorufin-O-deethylase. Pentoxyresorufin dealkylase activity, which is representative of the cytochrome P450 IIB 1/2 subfamily, was unaffected by IL6 whereas LPS reduced it to 33.7% of control values. Another hepatocyte-related parameter, serum concentration of alpha 1-acid glycoprotein (AGP), was increased by up to 3.5-fold over baseline by IL6 and 10-fold by LPS. Recombinant human interleukin-1 beta (rhIL1 beta) (10 micrograms/kg, corresponding to 5 x 10(4) U/rat) and recombinant human tumor necrosis factor alpha (rhTNF) (150 micrograms/kg corresponding to 24 x 10(4) U/rat) were both as potent as LPS (2.5 mg/kg) in increasing serum AGP levels and reducing hepatic microsomal monoxygenase activities. IL6 did not potentiate the effects of rhIL1 beta. Hepatic microsomal glucuronyltransferase activities were little affected by LPS and unaffected by rhIL6. Finally, rhIL6 was more potent after i.p. injection than after i.v. or s.c. injection. These results suggest that the effects of LPS, TNF and IL1 on the mixed-function oxidase system in vivo may be due partly to an induction of IL6 in vivo. The different sensitivities of the enzymes to IL6 but not to IL1 or TNF may be due to the involvement of two distinct mechanisms.

Different role of cytokine mediators in septic shock related to meningococcal disease and surgery/polytrauma

So far, there has been a tendency towards a uniform concept of the role and kinetics of TNF and other cytokines in septic shock. However, our comparison of data from different groups of shock patients clearly demonstrates marked differences. On the one hand, the cytokine pattern in experimental septic shock and meningococcal disease has similarities which include early burst releases of TNF and IL-6. On the other hand, intensive care unit patients which includes patients with polytrauma, surgery, burns and other underlying diseases have a completely different pattern of appearance of TNF and IL-6 in the circulation. We have not been able to detect bioactive TNF in the circulation of these patients, whereas others have measured elevated levels of immunoreactive TNF. Bioactive IL-6 can be detected in serum; however, the levels are often fluctuating and there is no common pattern of appearance. These differences probably reflect differences in the release of endotoxin and the immunological status of the patients. TNF inhibitors and soluble TNF receptors probably play an important role. Experimental models for septic shock most commonly use administration of live bacteria or endotoxin to anesthesized healthy animals. This appears to be a good model for meningococcal disease, but not for intensive care unit patients.

Interleukin-1 alpha prevention of the lethality of Escherichia coli peritonitis

Interleukin-1 (IL-1) is an inflammatory mediator with a variety of described physiologic functions. IL-1 alpha has been shown to confer a survival advantage to experimental animals when administered before a lethal bacterial challenge. The experiments reported here were performed to define the effective pretreatment interval of a single intravenous dose of IL-1 alpha in a murine model of bacterial peritonitis, to examine the differential induction of cytokines in animals with and without IL-1 alpha pretreatment, and to assess differences in histologic evidence of end organ damage. IL-1 alpha (27 micrograms/kg iv) conferred a survival advantage to mice given a lethal challenge of live Escherichia coli (2 x 10(8) CFU/mouse ip) when the pretreatment was given 2 to 24 hr before the bacterial inoculum. Longer pretreatment intervals were not significantly protective. Treatment with IL-1 alpha at 1 hr after bacterial inoculum also did not improve survival. Mice pretreated with IL-1 alpha developed significantly lower peak serum levels of TNF-alpha after E. coli injection than did control mice. Pretreated and control mice had similar peak serum levels of IL-6 after bacterial challenge; however, IL-1 alpha-pretreated mice had a less prolonged elevation of serum levels of IL-6. IL-1 alpha-pretreated animals were protected from the histologic evidence of end organ damage seen in control animals. Thus, in this model of E. coli peritonitis pretreatment with a single intravenous dose of IL-1 alpha confers a significant protective effect when given within a limited time range. Treatment outside this interval has no apparent beneficial effect.(ABSTRACT TRUNCATED AT 250 WORDS)

Kupffer cell autoregulation of IL-1 production by PGE2 during hepatic regeneration

The mammalian liver possesses the ability to regenerate to its original size after a 70% partial hepatectomy (PHx). The capacity of rat Kupffer cells (KC) isolated at specific intervals following PHx to produce interleukin-1 (IL-1) and prostaglandin E2 (PGE2) in response to endotoxin (LPS) was evaluated in standard RPMI-1640 (1200 microM L-arginine) and arginine-depleted RPMI-1640 (10 microM L-arginine) media. Regenerating liver KC 48-120 hr following PHx responded to LPS with a significantly greater (p less than 0.05) production of IL-1 in standard RPMI-1640. When 10 microM L-arginine RPMI-1640 was used to simulate the high arginase activity low L-arginine levels of the hepatic microenvironment, regenerating liver KC production of IL-1 was further increased (p less than 0.05). During the same time period, regenerating liver KC also produced significantly (p less than 0.01) more PGE2 than sham KC in both high and low arginine media. When the cyclooxygenase inhibitor indomethacin (10 microM) was added to low arginine cultures, the PGE2 production was inhibited, and IL-1 production was upregulated (p less than 0.05). We conclude that during hepatic regeneration KC IL-1 production is elevated but controlled in an autoregulatory fashion by KC PGE2 production.

Interleukin 10: an overview

Since the original description of interleukin-10, a wealth of information concerning its biological properties has been gathered. Studies in vitro have rapidly identified both immunostimulatory and immunosuppressive activities for IL-10. Based on these findings, in vivo studies were initiated in a variety of animal disease models to assess the importance of these activities. This review will summarize the pleiotropic properties of IL-10 and will survey current research regarding the potential of IL-10 to regulate acute and chronic inflammatory reactions.

A recombinant human receptor antagonist to interleukin 1 improves survival after lethal endotoxemia in mice

Interleukin 1 (IL-1) is an endogenously produced cytokine that mediates a variety of physiological effects that may be beneficial or deleterious to the host. C57Bl/6 mice treated intravenously with a recently characterized human recombinant receptor antagonist protein to IL-1 (IL-1ra) had improved survival when treated after a lethal Escherichia coli endotoxin (lipopolysaccharide [LPS]) challenge. IL-1ra was effective when treatment was initiated after LPS, and intravenous administration every 4 h for 24 h was required. Serum levels of tumor necrosis factor (TNF) activity after LPS and in vitro TNF cytotoxicity were not altered by treatment with IL-1ra. These experiments provide direct evidence that the lethal effects of LPS may be mediated through the action of IL-1 and that the IL-1ra can provide a new treatment strategy for disease processes mediated via this cytokine.

On radiation damage to normal tissues and its treatment. I. Growth factors

The first part of the review outlines the classical interpretation of radiation damage to normal organs based on dose-response relationships for clonogenic cell survival and tissue kinetics. Proliferative organization of critical cell lineages (three-compartmental or H-type and one-compartmental or F-type) is considered as an additional determinant in the development of overt radiation injury. This leads to testable predictions concerned with divergent outcomes of stimulation of cell proliferation after radiation exposure using polypeptide growth factors. The prediction of favourable effects of such stimulation in H-type lineages is borne out by recent experiments on treatment with cytokines of radiation-induced haemopoietic insufficiency. The second prediction of deleterious effects of proliferative stimulation in recently, heavily irradiated F-type cell lineages remains to be verified or refuted.