There is more than one interleukin 1

Effects of monoclonal antibodies to specific epitopes of rat interleukin-1 beta (IL-1 beta) on IL-1 beta-induced ACTH, corticosterone and IL-6 responses in rats

Recently, we developed a panel of monoclonal antibodies (MoAbs) to rat IL-1 beta and found that MoAbs binding to the aminoacid sequences 66-85 and 123-143 of mature rIL-1 beta inhibited the binding of rIL-1 beta to murine EL4 cells. Here we study whether MoAbs to these and other domains of IL-1 interfere with the biological effects of rIL-1 beta in adult male rats in vivo. Administration of rIL-1 beta (1 or 5 micrograms/kg i.v.) enhanced the plasma concentrations of ACTH, corticosterone (CORT) and of IL-6 in a time- (0.5-4 h) and dose-dependent manner. Because 2 h after 5 micrograms/kg i.v., all three parameters were consistently elevated, this dose and time interval was used for further studies. Prior to injection, rIL-1 beta was incubated alone or in the presence of a MoAb (10 mg/kg) for 30 min at 37 degrees C or at 4 degrees C. Plasma ACTH, CORT and IL-6 responses to these mixtures are compared to those obtained after preincubation of rIL-1 beta with a non-IL-1 binding MoAb (PEN7). SILK 3, a MoAb that binds to the 66-85 domain of rIL-1 beta, reduced the ACTH and IL-6 responses by 48 and 45% respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Endotoxin-induced appearance of immunoreactive interleukin-1 beta in ramified microglia in rat brain: a light and electron microscopic study

Interleukin-1 plays an important role as mediator of endotoxin-induced responses in the brain such as fever, sleep, anorexia, behavioural and neuroendocrine changes. In the present study, interleukin-1 beta immunocytochemistry has been performed at the light and electron microscopic level to study the cellular and subcellular localization of interleukin-1 beta in the brains of rats given endotoxin or saline. Light microscopic analysis of rats killed 4, 8 or 24h after endotoxin (2.5 mg/kg) given intraperitoneally or intravenously revealed a region-specific localization of immunoreactive interleukin-1 beta in macrophages and microglial cells. After saline treatment, no induction of interleukin-1 beta immunoreactivity occurred in the brain. After administration of endotoxin, many interleukin-1 beta-positive cells were found in the meninges, choroid plexus, circumventricular organs, cerebral cortex and hypothalamus. The number of interleukin-1 beta-positive microglial cells reached a maximum 8 h after administration of endotoxin, irrespective of the route of administration. In general, more interleukin-1 beta-positive microglial cells were found after intravenous than after intraperitoneal administration of endotoxin. Interleukin-1 beta-positive microglial cells were often grouped in patches in the vicinity of blood vessels. At the surface of the cerebral cortex, in the meninges, intermediate cell forms between interleukin-1 beta-positive macrophages and microglial cells were found. interleukin-1 beta-positive perivascular microglia were localized at the brain side of the basal lamina. Immunoreactive interleukin-1 beta was found at the luminal side of the endothelial cells lining the venules. Furthermore, microglial cells that extended their processes into the ependymal layer of the third ventricle were observed. Results of the electron microscopic studies revealed immunoreactive interleukin-1 beta in many cells with the cellular characteristics of microglial cells, but also, in some cells, identified as astrocytes. In microglial cells, immunoreactive interleukin-1 beta was found in the cytoplasm but not in the endoplasmatic reticulum or Golgi apparatus. These results show that after peripheral administration of endotoxin, immunoreactive interleukin-1 beta is induced in macrophages in the meninges and in the choroid plexus, as well as in microglial cells in parenchyma. Interleukin-1 beta produced by these cells may serve as a signal for adjacent or more distant targets (neurons, endothelial cells, microglial cells) to play a role in the induction of non-specific symptoms of sickness.

A preliminary exploration of the relationship between tumour necrosis factor (TNF) and monocytic in vitro production of interleukin-1 (IL-1) and internal organ dysfunction in severely burned patients

Biological assays were adopted in this study to examine the changes in serum tumour necrosis factor (TNF) activity and blood monocytic in vitro production of interleukin 1 (IL-1) in 24 severely burned patients. The myocardial and hepatic enzymes (which included aspartate aminotransferase (AST), creatine kinase (CPK), lactate dehydrogenase (LDH), alpha hydroxybutyric dehydrogenase (alpha-HBDH) and alanine amino-transferase (ALT) and some indices of biochemical metabolism (including lactic acid (LA), total protein (TP), albumin (Alb) and colloid osmotic pressure (COP)) were simultaneously measured. The results showed an evident increase in serum TNF activity and a decrease in in vitro production of IL-1 postburn; all the changes in TNF and IL-1 were correlated significantly with those of myocardial and hepatic enzymes in MOF patients. Furthermore, there were marked fever, hypoproteinaemia, tissue ischaemic and hypoxic symptoms such as hyperlacticaemia, and signs reflecting tissue hypercatabolic states. These all suggested that TNF and IL-1 might play important roles in the development of MOF.

The gingival crevicular fluid interleukin-1 beta and tumour necrosis factor-alpha levels in patients with rapidly progressive periodontitis

Cytokines are believed to play an important role in the pathogenesis of periodontal diseases. In the present study, gingival crevicular fluid (GCF) levels of two important cytokines, interleukin 1-beta (IL-1 beta) and tumour necrosis factor-alpha (TNF-alpha) and, in addition, serum IL-1 beta levels, were determined in patients with severe and rapid periodontal breakdown by use of ELISA. While IL-1 beta was detected in all of the GCF samples studied, TNF-alpha could only be detected in about half the samples. The mean GCF IL-1 beta level was 38.45 +/- 13.99 pg/mL, and the mean TNF-alpha level was 3.20 +/- 1.39 pg/mL, respectively. The GCF IL-1 beta levels also presented a strong positive correlation with the mean pocket depths. Although weak, both of the cytokines also presented correlations with the presence of bleeding on probing. Additionally GCF samples contained increased IL-1 beta levels when compared with the serum samples suggesting local production mechanisms. The findings of the present study suggest that these cytokines may be involved in the pathogenesis of periodontal diseases (IL-1 beta being more significant), and also may help in defining the active phase of periodontal breakdown.

Interleukin-1 beta (IL-1 beta) and acute leukemia: in vitro proliferative response to IL-1 beta, IL-1 beta content of leukemic cells and treatment outcome

We evaluated the in vitro proliferative response to exogenous IL-1 beta in terms of tritiated thymidine (3H-TdR) incorporation in leukemic cells obtained from 119 patients with various types of acute leukemia. The content of IL-1 beta in leukemic cells was measured by enzyme-amplified sensitivity immunoassay. We observed a significant proliferative response to exogenous IL-1 beta in leukemic cells from 27/66 patients with de novo AML, 1/29 patients with ALL, 2/3 patients with AUL, 8/12 patients with AML arising from MDS, 4/7 patients with myeloid crisis of CML, and 0/4 patients with lymphoid crisis of CML. Proliferation was marked in myeloid leukemic cells of a more premature stem cell origin. There were no significant differences in proliferative responses among the different FAB classes of de novo AML. The IL-1 beta content of leukemic cells was low in patients with lymphoid leukemia, but there was no significant difference among the various types of myeloid leukemia. There was no correlation between the proliferative response to exogenous IL-1 beta and the IL-1 beta content of leukemic cells. When we correlated the proliferative response to exogenous IL-1 beta with treatment outcome in patients with de novo AML, we found the rate of complete remission (CR) to be lower in those with a high proliferative response. We noted a longer duration of CR (p = 0.07) and of survival (p < 0.05) in patients with a low proliferative response. Thus, a high proliferative response to IL-1 beta in the cells of AML patients may indicate a poor prognosis.

Keratinocyte growth factor as a cytokine that mediates mesenchymal-epithelial interaction

Keratinocyte growth factor (KGF) is a member of the heparin-binding fibroblast growth factor family (FGF-7) with a distinctive pattern of target-cell specificity. Studies performed in cell culture suggested that KGF was mitogenically active only on epithelial cells, though from a variety of tissues. In contrast, KGF was produced solely by cells of mesenchymal origin, leading to the hypothesis that it might function as a paracrine mediator of mesenchymal-epithelial communication. Biochemical analysis and molecular cloning established that the KGF receptor (KGFR) was a tyrosine kinase isoform encoded by the fgfr-2 gene. Many detailed investigations of KGF and KGFR expression in whole tissue and cell lines largely substantiated the pattern initially perceived in vitro of mesenchymal and epithelial distribution, respectively. Moreover, functional assays in organ culture and in vivo and analysis of agents regulating KGF expression reinforced the idea that KGF acts predominantly on epithelial cells. While the data do not implicate a KGF autocrine loop in neoplasia, paracrine sources of factor or ligand-independent signaling by the KGFR might contribute to malignancy. Alternatively, because of its differentiation-promoting effects, KGF may retard processes that culminate in uncontrolled cell growth.

Effects of macrophage depletion on the induction of histidine decarboxylase by lipopolysaccharide, interleukin 1 and tumour necrosis factor

1. Our previous work has shown that injection into mice of lipopolysaccharide (LPS) and the cytokines interleukin 1 (IL-1) and tumour necrosis factor (TNF) induces histidine decarboxylase (HDC), the enzyme forming histamine, in various tissues such as liver, lung, spleen and bone marrow, but not in the blood. The induction of HDC also occurs in nude mice and mast cell-deficient mice. On the other hand, haematopoietic cytokines such as IL-3, granulocyte colony-stimulating factor (G-CSF) and granulocyte-macrophage CSF (GM-CSF) only induce HDC in the haematopoietic organs, i.e. bone marrow and spleen. In the present study, the effect of macrophage depletion on the induction of HDC was examined. 2. On day 1 after a single intravenous injection of a macrophage depletor (liposomes encapsulating dichloromethylene diphosphonate, which is toxic when ingested into macrophages), macrophages were almost completely depleted in the liver and reduced by about 50% in the spleen and bone marrow, but not significantly affected in the lung. On day 3, the degrees of the depletion were similar to those of day 1. In the spleen, macrophages were depleted in the red pulp, and there was a structural destruction. 3. In macrophage-depleted mice, the induction of HDC by LPS, IL-1 alpha or TNF-alpha was not impaired in the liver, and was potentiated in the lung and bone marrow. The induction of HDC was decreased only in the spleen at day 3. 4. HDC was not induced by LPS in the spleen of the adult rat, which is correspondingly inactive in haematopoiesis.5 These results indicate that the major cells in which HDC activity is induced in response to LPS, IL-1 and TNF are not circulating granulocytes, circulating monocytes, T cells derived from thymus, mast cells or phagocytic macrophages. Based on these results, we discuss the possibility that the major cells in which HDC was induced in non-haematopoietic and haematopoietic organs were endothelial cells and haematopoietic precursor cells respectively.

Activated T lymphocytes in epiretinal membranes from eyes of patients with proliferative diabetic retinopathy

BACKGROUND

To investigate the potential contribution of immune-mediated processes to the development of proliferative diabetic retinopathy (PDR), an immunohistochemical study was undertaken to characterize the infiltrating immune cells in epiretinal membranes from the eyes of patients with PDR.

METHODS

A total of 18 PDR epiretinal membrane specimens obtained surgically from pars plana vitrectomy were studied by using a panel of monoclonal antibodies against T lymphocytes (CD4 and CD8), interleukin-2 (IL-2) and interleukin-2 receptors (IL-2R).

RESULTS

Twelve of 18 specimens (67%) contained CD4-positive cells and 13 of 18 (73%) contained CD8-positive cells. IL-2 was found in 12 of 18 samples (67%), of which 11 also contained CD4-positive cells, and IL-2R was detected in 10 of 18 membranes (56%), of which 9 contained CD4-positive cells and released IL-2. Most of the IL-2R-positive membranes were from type I diabetic patients, 40% of them from patients younger than 40 years.

CONCLUSION

Our study demonstrated the involvement of activated immune cells and release of lymphokine(s) in more than half of the diabetic epiretinal membranes tested and revealed that the processes of immune responses and the biological effects of lymphokine(s) may play an important part in the development of epiretinal membranes of PDR, especially in young-onset and type I diabetes.

Serum levels of tumor necrosis factor-alpha, interleukin-1, and interleukin-6 in hemorrhagic fever with renal syndrome

Hemorrhagic fever with renal syndrome is an acute viral disease caused by hantavirus. On the basis of clinical observation, the illness is divided into five sequential stages: febrile, hypotensive, oliguric, diuretic, and convalescent. Because interleukin-1 (IL-1), tumor necrosis factor-alpha (TNF-alpha), and interleukin-6 (IL-6) are mediators responsible for fever, septic shock, and acute phase protein induction, we examined, using ELISA, the presence of these three cytokines in 276 sera collected during the Korean Conflict from 110 patients. Detectable levels (> 20 pg/ml) of TNF-alpha, IL-1 beta, and IL-6 occurred in 14, 14, and 33% of these samples, respectively. There was a significant correlation between serum levels of IL-1 beta and TNF-alpha (r = 0.66, p < 0.001), IL-1 beta and IL-6 (r = 0.59, p < 0.001), and IL-6 and TNF-alpha (r = 0.71, p < 0.001). The pathophysiologic processes of HFRS do not have clear or consistent correlations with alterations in the levels of the cytokines studied.

Effect of etodolac on prostaglandin E2 biosynthesis, active oxygen generation and bradykinin formation

The inhibitory actions of etodolac on prostaglandin (PG) E2 biosynthesis, active oxygen generation and bradykinin formation were compared with those of indomethacin, diclofenac Na, piroxicam, naproxen, ketoprofen and aspirin. The inhibitory action (IC50 5.35 x 10(-8) M) of etodolac on PGE2 biosynthesis in rabbit articular chondrocytes stimulated by interleukin-1 (IL-1) beta was about 1/5 that of indomethacin. The inhibitory action of etodolac on spontaneous PGE2 biosynthesis in rabbit gastric epithelial cells (RGEs) (IC50 2.27 x 10(-5) M) and Madin-Darby canine kidney cells (MDCKs) (IC50 4.54 x 10(-7) M) was much less than that in rabbit articular chondrocytes stimulated by IL-1 beta and about 1/19 and 1/9 that of indomethacin in rabbit gastric epithelial cells (RGEs) and Madin-Darby canine kidney cells (MDCKs), respectively. The inhibitory action of etodolac on active oxygen generation was similar to that of indomethacin and piroxicam, and more potent than that of naproxen, ketoprofen and aspirin. The inhibitory action of etodolac on bradykinin formation was the most potent among the seven anti-inflammatory drugs tested. Both etodolac and bromelain inhibited the inflammatory pain in concanavalin A-treated paws of rats in a dose-dependent manner, but indomethacin did not. These results indicate that etodolac is an anti-inflammatory drug which suppress IL-1 beta-stimulated PGE2 biosynthesis in rabbit articular chondrocytes, active oxygen generation and bradykinin formation. It has less suppressive action against spontaneous PGE2 biosynthesis in RGEs and MDCKs. Thus, etodolac is considered to be a safe anti-inflammatory drug for clinical use.

An in vivo study of hepatic and splenic interleukin-1 beta mRNA expression following oral PSK or LEM administration

The effects of orally administered biological response modifiers (BRMs) in preventing postoperative micro liver metastasis of primary colorectal cancer were examined in experimental animals. The two BRMs tested were Krestin (PSK) and Lentinus edodes mycelia (LEM). In previous experiments, we found that oral administration of PSK or LEM suppressed liver metastasis and prolonged the survival period. We also found that these agents elevated the liver natural killer (NK) and liver macrophage activities. In the present study in vivo, using reverse transcriptase-polymerase chain reaction (RT-PCR), we examined whether or not the liver and spleen have cytokines which would induce NK cells and macrophages, and whether or not the liver and spleen have cytokines induced by NK cells or macrophages. We placed emphasis on the examination of interleukin (IL)-1 beta expression in the liver and spleen in vivo. Two to six hours after oral administration of PSK or LEM (1 g/kg) to mice, IL-1 beta levels in the liver and spleen rose, and they returned to their baseline levels 24 h later. These findings suggest two possibilities: (1) hepatic IL-1 beta is potentiated by these agents soon after administration, resulting in activation of liver NK cells or macrophages, or (2) these agents stimulate IL-1 beta production by liver macrophages, and the produced IL-1 beta activates liver NK cells or liver macrophages (Kupffer cells). The results of this in vivo study suggest that the potentiation of hepatic and splenic IL-1 beta by PSK and LEM is involved in the early phases of suppression of micro liver metastases of colorectal cancer.

Detection of interleukin-6 and prostaglandin E2 in bronchoalveolar lavage fluids of pigs experimentally infected with Mycoplasma hyponeumoniae

In this study, interleukin-6 (IL-6) and prostaglandin E2 (PGE2) were detected in the bronchoalveolar lavage fluids (BALF) from pigs experimentally infected with Mycoplasma hyopneumoniae. IL-6 was detected at 2 weeks post-inoculation (PI), and significantly increased levels of PGE2 were observed at 4 weeks PI. In the BALF collected from infected pigs at 4 weeks PI, the levels of IL-6 increased significantly in the pigs with pneumonic lesions. However, increased levels of PGE2 were observed in all the infected pigs.

Expression of HLA-DR antigen and smooth muscle cell differentiation markers by valvular fibroblasts in degenerative aortic stenosis

OBJECTIVES

This study was designed to analyze the functional characteristics of fibroblasts present in aortic valves with degenerative stenosis.

BACKGROUND

Morphologic analysis of degenerative stenosis of tricuspid aortic valves has revealed an extensive interstitial fibrosis.

METHODS

Stenotic aortic valves collected during aortic valve replacement and control valves collected at autopsy were fixed in formaldehyde, cryosectioned and stained with antibodies against leukocyte markers, HLA-DR and intracellular filaments. Fibroblasts isolated from stenotic valve and skin explants were grown in cell culture, and their proliferative activity was analyzed by cell counting and uptake of tritiated thymidine.

RESULTS

In the stenotic valves nearly all interstitial cells expressed vimentin, and approximately 60% of the cells also expressed alpha-actin and desmin. HLA-DR was present on inflammatory cells as well as on one-third of the fibroblast-like cells in the interstitium. Macrophages were found in the interstitium and T lymphocytes close to calcium deposits and in subendothelial areas. In control valves, fibroblasts expressed vimentin but not alpha-actin or desmin. Few inflammatory cells were present in these valves, and HLA-DR expression was restricted to the endothelial surface. In culture, stenotic valve fibroblasts had a reduced ability to proliferate in serum and to activate DNA synthesis in response to growth factors compared with skin fibroblasts from the same patient.

CONCLUSIONS

The observation that fibroblasts present in aortic valves with degenerative stenosis express smooth muscle cell characteristics and HLA-DR antigen and show signs of cellular senescence in vitro suggests that they are in a state of chronic activation similar to that observed in fibromatosis and scleroderma lesions.

Suppression of interleukin-1 beta and tumour necrosis factor-alpha biosynthesis by cadmium in in vitro activated human peripheral blood mononuclear cells

Cadmium is a highly toxic element responsible for acute and chronic toxicity in man. There is evidence that cadmium induces pathophysiological effects by modulating components of the immune system. Cytokines are being increasingly recognized as essential mediators of normal and pathologic immune responses. Cadmium at concentrations varying from 1.0 x 10(-4) to 3.3 x 10(-6) M inhibited the phytohemagglutinin induced production of interleukin-1 beta and tumour necrosis factor-alpha, in in vitro activated human peripheral blood mononuclear cells. The messenger RNA levels of interleukin-1 beta and tumour necrosis factor-alpha were examined during a 24-h culture period, at different time points. The decreased messenger RNA levels at the time points of the maximum expression of interleukin-1 beta and tumour necrosis factor-alpha indicate that cadmium suppresses their production at the transcriptional level.

Immunogenicity of the Escherichia coli fimbrial antigen K99 when expressed by Salmonella enteritidis 11RX

Salmonella strains expressing the Escherichia coli fimbrial protein K99 were used to immunize adult mice, and the resulting anti-K99 T-cell responses were examined. Immunized animals displayed delayed-type hypersensitivity responses when challenged with K99 in the footpad. Lymphoid cells from immunized animals proliferated and released cytokines when cultured in vitro with K99 or peptides generated by cyanogen bromide treatment; the T cells which responded had the CD4+ phenotype.

Selective release of a processed form of interleukin 1 alpha

Interleukin 1 alpha (IL-1 alpha) is synthesized as a 33 kDa form and proteolytically processed into a 17 kDa form. Although IL-1 alpha has no signal peptide, it is released from cells. To investigate the relationship between the processing and release of IL-1 alpha, human bladder carcinoma cells (HTB9 5637) which express IL-1 alpha constitutively, were treated with calcium ionophore (A23187). A23187 induced the processing of 33 kDa IL-1 alpha and selectively released processed 17 kDa IL-1 alpha, without any change in the release of 33 kDa IL-1 alpha. When extracellular calcium was chelated by EGTA, or when intracellular calpain was inhibited by the cell-permeable cysteine-protease inhibitor, E64d, the processing of 33 kDa IL-1 alpha was significantly blocked, the release of 33 kDa IL-1 alpha being unchanged. These results indicate that the release of IL-1 alpha was accompanied by the processing of 33 kDa IL-1 alpha.

Acute joint inflammation--mechanisms and mediators

1. This review discusses factors contributing to acute joint inflammation, particularly sensory neuropeptides. 2. Mediators known to contribute importantly to the inflammatory process include cytokines, eicosanoids, complement and the kinin systems, histamine and 5-hydroxytryptamine and sensory neuropeptides substance P (SP) and calcitonin gene-related peptide (CGRP). 3. The pro-inflammatory neurokinins, SP and CGRP, are present in nerves innervating joints and could significantly contribute to the increased vascular permeability and hyperaemia occurring in acute arthritis. 4. Although perhaps contributing to the pathogenesis of chronic inflammatory joint disease, there is little evidence for involvement of the sympathetic nervous system in acute models of inflammation.

Interleukin-1 beta stimulates collagenase production by cultured human periodontal ligament fibroblasts

To examine the effects of interleukin-1 beta (IL-1 beta) on collagenase production by human periodontal ligament fibroblasts (PLF) and gingival fibroblasts (GF) in culture, collagenase activity in conditioned media was determined using a novel procedure that circumvented interference by enzyme inhibitors. Fibroblasts obtained from five paired periodontal ligament and gingival tissues were cultured for two weeks, and then incubated for a further 72 h in alpha-MEM supplemented with various concentrations of IL-1 beta (0 to 1250 pg/ml). The conditioned media from individual cultures were harvested and treated with dithiothreitol to inactivate TIMPs, and then with APMA, to activate the latent collagenase. Collagenase activity was measured fluorometrically using FITC-collagen as a substrate. IL-1 beta induced a approximately 2.4 to 5.2-fold increase in collagenase activity in PLF compared to a approximately 1.4 to 2.2-fold increase in GF. These results are in contrast to previous studies in which collagenase activity was measured in the presence of TIMPs, and indicate that PLF are more sensitive to IL-1 beta than GF. Since both PLF and GF are present in periodontal lesions, it is possible that collagenase secretion stimulated by exposure to inflammatory cell products such as IL-1 beta may participate in the destruction of collagen fibers involved in periodontal attachment.

Cytokines and metabolic dysfunction after severe head injury

Patients with head injury must overcome central as well as peripheral metabolic insults. In addition to specific tissue damage to the brain, a cellular biochemical cascade occurs that can negatively affect organ function, cause a systemic response to injury, and may cause secondary tissue injury. The metabolites involved in this cascade are numerous and complex. Cytokines are important cell-to-cell communication mediators during injury. It is speculated that cytokines, such as interleukin 1 (IL-1), interleukin 6 (IL-6), tumor necrosis factor (TNF), and interleukin 8 (IL-8), which are found in elevated amounts in both human and basic trials after head injury, play a role in the cellular cascade of injury. Some of the metabolic events produced by small doses of cytokine infusion in animals, as well as humans, include fever, neutrophilia, muscle breakdown, altered amino acid metabolism, depression of serum zinc levels, production of hepatic acute phase reactants, increased endothelial permeability, and expression of endothelial adhesion molecules. These are all known sequelae of severe head injury. Cytokines have also been implicated in organ failure. Infusion of cytokines in basic science trials revealed that organ functions of the gut, liver, and lung are negatively altered by high-dose cytokine infusion. Infusion of certain cytokines has been shown to cause death of brain cells, increase blood-brain barrier permeability, and cause cerebral edema. This suggests that cytokines may also play a role in the sequelae of organ demise. These effects of cytokines have been attenuated in basic trials by blocking the initial signaling system of cytokines or by decreasing serum cytokine activity. We hypothesize that cytokines that are elevated after head injury play a role in the pathology of injury, including altered metabolism and organ demise.

Smokeless tobacco effects on monocyte secretion of PGE2 and IL-1 beta

The use of smokeless tobacco (ST) products is associated with mucosal lesions, gingival recession, and attachment loss at the site of tobacco placement. Monocytes/macrophages are primary producers of PGE2 and IL-1 beta, inflammatory mediators which are thought to play a role in the destruction of the periodontium. The purpose of this study was to determine the effect of ST alone and in combination with a major stimulator of inflammation, bacterial lipopolysaccharide (LPS), on monocyte secretion of these mediators. Peripheral blood monocytes (PBM) were isolated by counterflow centrifugal elutriation from 15 healthy donors who were non-ST users. PBM were incubated for 24 hours in RPMI 1640 containing various concentrations of ST (0%, 0.005%, 0.01%, 1%) with or without 10 micrograms/ml LPS (Porphyromonas gingivalis LPS or Escherichia coli LPS). Of the ST preparations, only 1% ST resulted in PBM mediator secretion (7.7 +/- 2.0 ng/ml for PGE2 and 1.3 +/- 0.2 ng/ml for IL-1 beta) above that of control (unstimulated) cultures. Furthermore, the combination of 1% ST and LPS resulted in a potentiation of PGE2 release (5-fold for E. coli LPS + 1% ST and 10-fold for P. gingivalis LPS + 1% ST; P < 0.0001, one-way ANOVA) relative to the LPS preparations alone. In contrast, PBM IL-1 beta release decreased more than 2-fold upon E. coli LPS and 1% ST exposure, relative to treatment with E. coli LPS alone (P < 0.0001, one-way ANOVA).(ABSTRACT TRUNCATED AT 250 WORDS)

Interleukin-1 and related pro-inflammatory cytokines in the treatment of bacterial infections in neutropenic and non-neutropenic animals

Bacterial infections in the immunocompromized host cause considerable mortality, and even the recently developed antimicrobial strategies often fail to cure these infections, especially in granulocytopenic patients. Cytokines and hematopoietic growth factors have been shown to stimulate host defense mechanisms in vitro and in vivo. We discuss the possible role of the pro-inflammatory cytokines interleukin-1, tumor necrosis factor-alpha, interleukin-6 and interleukin-8 as modulators of host resistance to bacterial infections. Interleukin-1 has been shown effective in various animal models of potentially lethal bacterial infection, even during severe granulocytopenia. The protective mechanism of interleukin-1 may be mediated via downregulation of cytokine receptors and cytokine production, and via induction of acute phase proteins. Moreover, in subacute and chronic infections interleukin-1 interferes with microbial outgrowth, via mechanisms that have only been partially elucidated.

Growth suppression and astrocytic differentiation of glioma cells by interleukin-1

The effect of recombinant human interleukin-1 (rHuIL-1) derivatives on human glioma cell lines was examined in vitro. Five glioma cell lines, U-251 MG, U-373 MG, U-87 MG, A-172, and T98G, were incubated in medium containing 1% fetal calf serum and various concentrations of different type of rHuIL-1: OCT-43 (rHuIL-1 beta), OCT-7000 (rHuIL-1 alpha), and OCT-8000 (rHuIL-1 alpha). The high-affinity IL-1 receptors were expressed in the U-251 MG and U-373 MG cell lines, and rHuIL-1 was found to suppress cell growth and to induce morphological differentiation of these cell lines. Growth inhibition occurred in a dose-dependent manner in concentrations or rHuIL-1 ranging between 1 and 100 ng/ml. Interestingly, rHuIL-1 induced a transient growth of glioma cells shortly after administration, then suppressed cell growth with accompanying elongation of cytoplasmic processes. This unique process of transient growth stimulation followed by growth suppression was parallel to the efficacy of bromodeoxyuridine uptake in the rHuIL-1-treated cells. Concomitantly, accumulation of glial fibrillary acidic protein and cyclic adenosine monophosphate contents was observed in four glioma cell lines. Continuous rHuIL-1 treatment for longer than 30 days elicited irreversible astrocytic terminal differentiation. These results indicate that IL-1 is an effector on the growth regulation of glioma cells, resulting in astrocytic differentiation in vitro.

Cytokine-mediated gene therapy for cancer

BACKGROUND

Significant interest has been generated in the gene therapy of cancer. One strategy involves tumor-directed cytokine gene transfer and its effects on tumor immunobiology.

METHODS

The authors review the current literature pertaining to cytokine gene therapy of cancer and provide a description of gene transfer methods currently being evaluated.

RESULTS

Several cytokine gene transfer models have been described involving at least 12 different cytokines. The introduction of cytokine genes into experimental animal tumors improves their ability to be recognized and destroyed by the host immune system. Certain cytokines will regulate phenotypic properties such as major histocompatibility complex antigens, immunosuppressive peptides, protooncogenes or endogenous cytokine production. Cytokine-transduced tumors attract an inflammatory exudate in vivo that generally results in tumor destruction. The nature of the infiltrate (lymphocytic, mononuclear, granulocytic) cannot always be predicted from the known biological properties of each cytokine. Untransduced bystander tumor cells are usually also destroyed. Some, but not all, cytokine transductions result in the generation of systemic major histocompatibility complex-restricted, tumor immunity. It has been hypothesized that the local continuous production of cytokines by tumor cells provides an optimal microenvironment for antigen recognition and the generation of T-cell immunity.

CONCLUSIONS

These experimental observations hold promise for the clinical application of genetically engineered tumor vaccines.

Cytokines in the treatment of fungal infections

The incidence of invasive fungal infections in the immunocompromized host has increased during the past decade. Even the recently developed antifungal drugs are unable to cure these infections in patients with severely impaired host defense mechanisms. Cytokines have great potential to augment host resistance and as adjunctive therapy of invasive mycoses. We discuss the mechanisms of host defense against invasive candidiasis, aspergillosis, and cryptococcosis, and review the use of cytokines and growth factors in this setting. Interleukin-1 has been shown effective in an animal model of disseminated candidiasis, even during severe granulocytopenia. Interferon-gamma has been very effective as a modulator of resistance against a variety of fungal infections in vitro. The effect of interferon-gamma against disseminated candidiasis has been demonstrated in a mouse model. Activation of neutrophils is the main mechanism by which interferon-gamma enhances the elimination of Candida, and consequently the agent is not effective in severely granulocytopenic animals. Data on the role of colony-stimulating factors against fungal pathogens are accumulating, and trials with these agents for hematologic patients with invasive fungal infections are now being performed.

Regulation of macrophage gene expression by T-cell-derived lymphokines

Cytokines secreted from antigen-specific T lymphocytes provide important positive and negative control of inflammation through their effects on non-antigen-specific inflammatory leukocytes. These effects often involve modulation of gene expression. Lymphokine-inducible macrophage gene expression is largely controlled at the level of transcription. Multiple cis-acting sequence motifs cooperate with one another to produce patterns of expression that are relatively unique to individual genes. Members of trans-acting transcription factor families, which recognize related regulatory sequence elements, participate frequently in complex protein-protein interactions that generate remarkable complexity in terms of the number of potential combinations and the consequential functional differences exhibited by each combination. Thus, the remarkable plasticity of immune-mediated inflammation derives from combinations of finite numbers of options at several points in the cellular and molecular sequence.

Disturbances in the production of interleukin-1 and tumor necrosis factor in disseminated murine sporotrichosis

Production of Interleukin-1 (IL-1) and Tumor Necrosis Factor (TNF) by adherent peritoneal cells from BALB/c mice was measured at week 2, 4, 6, 8 and 10 after intravenous inoculation with 10(6) Sporothrix schenckii yeasts. As compared with age-matched controls, IL-1 and TNF production by adherent peritoneal cells from S. schenckii-infected mice was reduced severely at week 4 and 6 of infection and greater than normal at week 8 and 10. Moreover, between week 4 and 6 of infection there was a depression of delayed type hypersensitivity response to a specific whole soluble antigen, and an increase in fungal multiplication in the livers and spleens of infected mice. Thus, the deficits of cell-mediated immunity in mice with systemic S. schenckii infection may derive, in part, from impaired amplification of the immune response consequent to abnormal generation of IL-1 and TNF.

Production of active human interleukin-1 beta-converting enzyme in a baculovirus expression system

The cDNA coding for the precursor form of human interleukin-1 beta-converting enzyme (proICE) was expressed in Spodoptera frugiperda (Sf9) insect cells using a baculovirus expression system. The 45-kDa recombinant protein was further processed to several smaller forms of 32, 24, 20, 13 and 10 kDa. Active recombinant ICE derived from the baculovirus expression system (bvICE) was found to be present in soluble lysates of insect cells as an associated heterodimer consisting of 10- and 20-kDa subunits. The activity of bvICE was determined by conversion of precursor interleukin-1 beta (preIL-1 beta) to the mature form (mIL-1 beta) and via site-specific cleavage of a decapeptide which spans the ICE cleavage site in preIL-1 beta. The bvICE system was inhibited by an ICE inhibitor to the same extent as native ICE from the monocytic cell line THP-1. Expression of an active-site mutant (Cys285 to Ser) of proICE in insect cells resulted in the accumulation of partially processed (32-kDa) ICE. The availability of a facile expression system will permit further characterization of the biochemical properties and processing pathway of this unique protease.

Clinical significance of the change of blood monocytic interleukin-1 production in vitro in severely burned patients

Biological methods were employed to measure the dynamic changes in the in vitro IL-1 production by blood monocytes in 24 severely burned patients. The serum myocardial and hepatic enzymes (C-reactive protein) (CRP), plasma lactic acid (LA), etc. were simultaneously measured. The results showed an obvious decrease in blood monocyte IL-1 production in vitro and increases in CRP, LA and serum enzymes. These changes were more evident in patients complicated with organ injury, multiorgan failure and systemic infection. It is suggested that blood monocytes are superstimulated postburn in vivo and produced large amounts of IL-1 leading to exhaustion of monocyte function. These changes might promote the development of severe systemic infection and internal organ injury even multiple organ failure.

4-Deoxypyridoxine inhibits chronic granuloma formation induced by potassium permanganate in vivo

4-Deoxypyridoxine (4-DPD) is a potent antagonist of Vitamin B6 coenzyme which inhibits IL-1, lymphocyte proliferation and has demonstrated that tolerance to skin grafts can be induced by administering splenic cells to pyridoxine-deficient mice. Chronic inflammation induced by dorsal injections of 200 microliters of a 1:40 saturated crystal solution of potassium permanganate (KMnO4) in mice treated or untreated with 4-DPD (400 micrograms/dose), has been investigated. After 7 days all mice developed a subcutaneous granulomatous tissue indicative of a chronic inflammatory response, at the site of injection. KMnO4-treated mice injected intraperitoneally with 4-DPD (400 micrograms/dose) on 5 consecutive days (the first at the same time of induction of the granuloma) show a significant decrease in size and weight of granuloma when compared to mice not treated with 4-DPD (Controls). In addition, in all mice treated with 4-DPD there was a strong inhibition of TNF alpha in serum (P < 0.01) and in supernatant fluids (P < 0.05) from minced granuloma, while IL-6 was inhibited in the supernatant fluids (P < 0.05) of minced granulomas but was not detected in the serum of treated and untreated mice. In this study we show for the first time the antiinflammatory effect of 4-DPD on chronic inflammation and the inhibitory effect of TNF and IL-6 generation in supernatant fluids from minced granulomas.

Differences in interleukin 1 (IL-1), IL-6, tumor necrosis factor and IL-1 receptor antagonist production by human monocytes stimulated with muramyl dipeptide (MDP) and its stearoyl derivative, romurtide

The immunostimulatory reagents muramyl dipeptide (MDP) and its stearoyl derivative romurtide [MDP-Lys(L18)] were assessed for cytokine inducing activity in human monocytes. Both MDP and romurtide stimulated the production of interleukin-1 (IL-1), IL-6, tumor necrosis factor (TNF) and IL-1 receptor antagonist (IL-1Ra). Kinetics study indicated that IL-1, TNF and IL-1Ra were induced after 4 h stimulation but IL-6 was produced at a later phase. Romurtide induced these cytokines for longer period that MDP. Dose-response study indicated that romurtide was far more potent than MDP in induction of IL-1, IL-6 and TNF. Although the magnitude of the IL-1 and IL-6 induction was almost the same, that of TNF induction was greater in romurtide-stimulated monocytes than in MDP-stimulated cells. Among IL-1, IL-1 beta appeared to be a major product. In contrast to other cytokines, IL-1Ra was induced by MDP and romurtide in a similar dose and time dependent manner with similar magnitude of response. These studies indicate that MDP and romurtide, especially romurtide, are very potent inducers of both immunostimulatory and immunosuppressive cytokines by human monocytes but with different efficacy and kinetics.

Human recombinant interleukin-1 receptor antagonist blocks bone resorption induced by interleukin-1 beta but not interleukin-1 alpha

Both interleukin-1 alpha (IL-1 alpha) and interleukin-1 beta (IL-1 beta) are powerful stimulators of bone resorption in vivo and in vitro. Interleukin-1 receptor antagonist (IL-1ra) binds to many interleukin-1 receptors. It does not activate the receptor and effectively blocks the action of IL-1 alpha and IL-1 beta. In this study, human recombinant IL-1ra, at 100-fold excess, was found to block bone resorption in cultured mouse calvaria due to IL-1 beta but not IL-1 alpha. These observations may be explained by differential affinities of receptors for IL-1 alpha, IL-1 beta and rhIL-1ra on target bone cells.

Regulation of interleukin-1 receptors and hypothalamic-pituitary-adrenal axis by lipopolysaccharide treatment in the mouse

We measured iodine-125-labeled recombinant human interleukin-1 alpha (125I-IL-1 alpha) binding in the hippocampus, pituitary, liver, spleen and testis, and plasma adrenocorticotropic hormone (ACTH) and corticosterone levels after i.p. injection of various dose and treatment regimens of the bacterial endotoxin, lipopolysaccharide (LPS). Plasma ACTH and corticosterone levels were significantly increased at 2 h after acute administration of LPS (60 or 300 micrograms/mouse). 125I-IL-1 alpha binding in all peripheral tissues examined was significantly and comparably decreased at 2 h after a single injection of 30 micrograms or 300 micrograms LPS/mouse. On the other hand, 125I-IL-1 alpha binding in hippocampus was significantly decreased only after high dose administration of LPS (300 micrograms/mouse). In order to evaluate if activation of IL-1 in brain resulting in the observed decrease in 125I-IL-1 alpha binding may require more sustained exposure to endotoxin, we compared the effects of a single injection (60 micrograms/mouse) and two injections of LPS (30 micrograms/mouse each at 0 and 12 h). A single injection of LPS (60 micrograms/mouse) decreased 125I-IL-1 alpha binding in the testis but not in the hippocampus, while two LPS injections (30 micrograms/mouse each at 0 and 12 h) caused dramatic reductions in 125I-IL-1 alpha binding in both the hippocampus and testis.(ABSTRACT TRUNCATED AT 250 WORDS)

The induction of specific antitumor immunity by in vivo treatment with interleukin-1 and sonicated tumor extract in a murine model

BALB/c mice were pretreated intraperitoneally with interleukin-1 (IL-1) and sonicated tumor extract (SE) from plasmacytoma MOPC104E, 10, 7, and 4 days prior to the intraperitoneal or subcutaneous inoculation of MOPC104E cells, following which significant suppression was observed. The mean survival time and tumor diameter on day 21 were 46.7 days and 0 mm, respectively, in contrast to the 20.9 days and 20.4 mm of control mice. Mice pretreated with IL-1 and SE from MOPC104E (MOPC-SE) were not suppressed following fibrosarcoma MethA inoculation, which indicates the tumor specificity of immunity in this model. This systemically operating antitumor immunity was also achieved by the intramuscular administration of IL-1, or when tumor challenge was performed on day 7 or 14. Moreover, MOPC104E-specific delayed-type hypersensitivity was detected in these mice. The results of this study suggest the possibilities of a new type of active specific immunotherapy, which could prove useful as postsurgical adjuvant therapy for cancer patients.

Interleukin 1 beta inhibits gastric emptying in rats: mediation through prostaglandin and corticotropin-releasing factor

BACKGROUND/AIMS

Interleukin 1 beta (IL-1 beta) increases the release of corticotropin-releasing factor (CRF) in the brain through prostaglandin pathways. Because central CRF inhibits gastric motor function, the influence and mechanism of action of intracisternal injection of IL-1 beta on gastric emptying were investigated.

METHODS

The 20-minute rate of gastric emptying of a nonnutrient test meal was assessed by the phenol red methylcellulose method 30 minutes after injection of human recombinant IL-1 beta in conscious rats.

RESULTS

IL-1 beta injected intracisternally (0.01-1 ng) or intravenously (0.01-10 ng) dose-dependently decreased gastric emptying by 10%-82% and 0%-89%, respectively. The median effective dose (ED50) was 30-fold lower when IL-1 beta was injected intracisternally (0.1 ng) than intravenously (3 ng). The inhibitory effect of intracisternal IL-1 beta had a rapid onset (within 20 minutes) and was long-lasting (6 hours). Indomethacin (5 mg/kg, intraperitoneally) completely prevented the 61% inhibition induced by intracisternal IL-1 beta (0.1 ng) but had no effect on CRF-induced (600 ng) 72% inhibition of gastric emptying. The intracisternal injection of the IL-1 receptor antagonist (100 ng) or the CRF antagonist [DPhe12, [DPhe12,Nle21,38,C alpha MeLeu37]CRF12-41 (20 micrograms) prevented by 100% and 52%, respectively, the inhibition of gastric emptying evoked by intracisternal IL-1 beta (0.1 ng). The antagonists alone had no effect on basal gastric emptying.

CONCLUSIONS

IL-1 beta acts in the brain to induce a long-lasting inhibition of gastric emptying; IL-1 beta action is mediated through central IL-1 receptors and prostaglandin- and CRF-dependent mechanisms.

Up-regulation of cytokine production in alveolar macrophages by histogranin, a novel endogenous pentadecapeptide

Recently, histogranin (HN), a newly found pentadecapeptide, was shown to enhance tumor necrosis factor (TNF) production by alveolar macrophages (AM). In this study, we have investigated whether HN was present in tissues rich with immune cells and further explored the effect of HN and [Ser1]HN on the production of TNF and other key cytokines. Relatively high levels of immunoreactive (ir)-HN were found in rat lung (14.9 pmol/g) and spleen (12.3 pmol/g), indicating its localization in close proximity to macrophages/monocytes and lymphocytes. Furthermore, HN and [Ser1]HN (10(-8)-10(-7) M) stimulated basal and lipopolysaccharide (LPS)-induced interleukin 1 (IL-1) mRNA expression and IL-1 release from rat AM. [Ser1]HN also stimulated basal and LPS-induced interleukin-6 (IL-6) release. Although HN did not affect the kinetics of cytokine production, the maximal enhancing effect of HN was seen at 3 h for TNF, 6 h for IL-1 and 18 h for IL-6. These data indicate that HN can up-regulate a cytokine cascade involving TNF, IL-1 and IL-6 and suggest a role for this endogenous peptide in immune regulation.

Expression and purification of recombinant ovine interleukin-1 beta from Escherichia coli

An expression vector bearing the gene segment encoding the mature form of ovine interleukin-1 beta (OvIL-1 beta) was constructed. This vector provided a rapid method for obtaining Escherichia coli derived recombinant OvIL-1 beta (rOvIL-1 beta) using the expression plasmid pGEX-2T. The level of expression of fusion protein in the soluble fraction was approximately 20% of the total accumulated proteins. Affinity purification by glutathione-Sepharose yielded a fusion protein and subsequent thrombin cleavage of this material yielded rOvIL-1 beta. The specific activity of the purified recombinant protein was 10(3)-10(4) times higher than the fusion protein. The rOvIL-1 beta was 10-100 times more potent than human interleukin-1 beta (HuIL-1 beta) in an ovine thymocyte proliferation assay, although they were of equal potency in the NOB-1/CTLL assay. This simple purification method, which produces purified rOvIL-1 beta with a high specific activity (approximately 10(8) U mg-1), will now make it possible to evaluate the in vivo effects of IL-1 beta in sheep.

Mapping of the regulatory type I alpha and catalytic beta subunits of cAMP-dependent protein kinase and interleukin 1 alpha and 1 beta in the pig

The genes coding for the regulatory type I alpha subunit (PRKAR1A) and the catalytic beta subunit (PRKACB) of cAMP-dependent protein kinase and the genes for interleukin 1 alpha (IL1A) and interleukin 1 beta (IL1B) were localized in the pig by means of radioactive in situ hybridization. PRKAR1A was mapped to 12p1.4 and PRKARB to 6q3.1-->q3.3. The genes for IL1A and IL1B were both assigned to Chromosome (Chr) 3, in the region q1.2-->q1.3 and q1.1-->q1.4, respectively. The cDNA nucleotide sequences of these porcine genes were compared with those of human, mouse, and cattle. The location of the genes was discussed in relation to the position of their homologous loci in these mammalian species.

The synergistic antitumor effect of recombinant interleukin-1 and low-dose of cyclophosphamide in tumor-bearing mice

Intraperitoneal (i.p.) treatment of MOPC104E ascitic tumor-bearing BALB/c mice with interleukin-1 (IL-1) followed by a low dose of cyclophosphamide (CPA) resulted in synergistic prolongation of their survival time. This antitumor effect was abolished when administration of CPA preceded that of IL-1. The combined i.p. therapy also eradicated subcutaneous (s.c.) tumors, indicating a systemically operating antitumor mechanism. In Winn assay, splenocytes from MOPC104E-bearing mice treated with the combined therapy completely suppressed the growth of MOPC104E cells, but not that of another syngeneic tumor cell line, RL female-8 cells. This tumor-neutralizing activity was completely abrogated by treatment with anti-asialo-GM1 or anti-Thy1.2 and complement, and reduced by treatment with anti-Lyt2.2 and complement. Treatment of splenocytes with 1-leucine methyl ester (Leu0Me), which depletes natural killer (NK) cells and macrophages in vitro, did not affect the neutralizing activity.

Membrane-associated interleukin-1 promotes osteoclast-like cell formation in vitro

The effect of paraformaldehyde-fixed murine macrophage P388D1 cells on osteoclast-like cell formation was investigated in mouse marrow cultures. When mouse marrow cells were cocultured for 8 days with paraformaldehyde-fixed P388D1 cells stimulated with lipopolysaccaride (LPS), many tartrate-resistant acid phosphatase (TRACP)-positive multinucleated cells were formed. Non-stimulated, and paraformaldehyde-fixed P388D1 cells did not induce the formation of TRACP-positive multinucleated cells. Salmon calcitonin and indomethacin strongly inhibited the paraformaldehyde-fixed, LPS-stimulated P388D1 cells-induced TRACP-positive multinucleated cell formation. Monospecific anti-mouse recombinant IL-1 alpha serum inhibited TRACP-positive multinucleated cell formation in the presence of paraformaldehyde-fixed P388D1 cells stimulated with LPS. These results suggest that membrane-associated IL-1 on macrophages is responsible for the resorptive effect of paraformaldehyde-fixed P388D1 cells stimulated with LPS.

Comparative production of IL-1 beta and IL-1 alpha by LPS-stimulated human monocytes: ELISAs measurement revisited

There has always been an apparent discrepancy between the levels of IL-1 alpha and IL-1 beta mRNA and that of their corresponding proteins. Indeed, LPS-stimulated human monocytes produce about 10 times more IL-1 beta mRNA and IL-1 alpha mRNA, while the ratio of the corresponding proteins is the opposite, a difference that has been attributed to less efficient translation of IL-1 beta mRNA. Using a home-made ELISA that recognizes the 31-kDa precursor of IL-1 beta (proIL-1 beta), we found that LPS-stimulated human monocytes produced at least 20 times more IL-1 beta than IL-1 alpha, a ratio in accordance with the corresponding mRNA levels. This difference with previous reports is due to the fact that commercial ELISAs recognize, little if at all, proIL-1 beta. Furthermore, we found that cell lysis with CHAPS released significantly more IL-1 beta than did classical freeze-thawing.

Suppressive effect of intravenous immunoglobulins on the activity of interleukin-1

In order to study the effect of human immunoglobulin preparations for intravenous use (IVIg) on the production and activity of interleukin-1 (IL-1) derived from monocytes, we treated cultured monocytes with IVIg and examined the lymphocyte-activating factor (LAF) activity of IL-1 in the culture supernatants. The results showed that IVIg suppressed the activity from most healthy adults and some febrile children with acute respiratory disease or Kawasaki disease. Further studies revealed that intact Ig (whole molecular Ig) did not suppress the mRNA expression of IL-1 alpha or IL-1 beta in mononuclear cells, that intact Ig and pepsin-digested Ig inhibited the LAF activity of recombinant IL-1 (rIL-1) and also that intact Ig contains immunoglobulin (probably anti-IL-1 antibody) which binds with rIL-1 by dot blotting using biotin-streptavidin. These results suggest that IVIg suppresses neither IL-1 synthesis nor the release of IL-1 from monocytes but does neutralize IL-1 alpha and IL-1 beta activity by binding IL-1 proteins as an anti-IL-1 antibody.

Stimulation of the synthesis of histamine and putrescine in mice by a peptidoglycan of gram-positive bacteria

To clarify the base of in vivo biological activities of peptidoglycans of Gram-positive bacteria, the effects of a polysaccharide peptide of Staphylococcus epidermidis peptidoglycan (SEPS) on the synthesis of histamine and putrescine in BALB/c mice were examined and compared with those of a lipopolysaccharide (LPS or endotoxin) of Gram-negative bacteria. Within a few hours after its injection into BALB/c mice, SEPS induced histidine decarboxylase (HDC), the enzyme forming histamine, in the liver, lung, spleen and bone marrow, and ornithine decarboxylase (ODC), the enzyme forming putrescine, in the tissues except for the lung. SEPS induced HDC activity even in mast cell-deficient mice and in nude mice. These effects of SEPS were essentially the same as those of LPS. However, the dosage of SEPS capable of inducing HDC and ODC was much higher (100 to 1,000 times) than that of LPS. We have reported that C3H/HeN mice are resistant to SEPS in producing acute arthritis, and their productions of IL-1 and prostaglandin E2 are less than BALB/c mice sensitive to producing acute arthritis. In the present study, it was also found that C3H/HeN mice were markedly resistant to SEPS in inducing HDC activity.

Detection of interleukin-1 activity in human bladder cancer cell lines

Detection of interleukin (IL)-1 activity was studied in two human bladder cancer cell lines, T24 and EJ1, and one rat bladder carcinoma cell line, 804G. Significantly high proliferation of mouse thymocytes in the assay of IL-1 activity was observed in the conditioned medium (CM) of T24 cells, indicating that the cells released IL-1-like activity. Enzyme-linked immunosorbent assay (ELISA) and Northern blot analysis showed the presence of both IL-1 alpha and IL-1 beta in the CM of T24 cells and expression of mRNAs of both cytokines in the cells. Interleukin-1 activity in EJ1 cells, which produced a little activity, was induced by E. coli lipopolysaccharide (LPS) while it was not induced in T24 by either LPS or other test substances. Conditioned medium of T24 increased proliferation of both T24 and EJ1 in cell-growth assay. Further investigation of the mode of action and role of cytokines, especially those from tumor cells themselves, is necessary in relation to BCG or photodynamic therapy.