Showing papers on "Intraperitoneal injection published in 1998"

Brain Endothelial Cells Express Cyclooxygenase-2 during Lipopolysaccharide-Induced Fever: Light and Electron Microscopic Immunocytochemical Studies

Abstract: Cyclooxygenase-2 (COX-2), a key enzyme in the biosynthesis of prostaglandins, is induced in brain blood vessels by pyrogens, and its essential role in fever has been hypothesized. In this study, we determined (1) the type of cells that express cyclooxygenase-2 in brain blood vessels of lipopolysaccharide-treated rats, and (2) the precise relationship between the time course of fever and that of cyclooxygenase-2 protein expression in these cells. Five hours after the lipopolysaccharide injection (100 microg/kg, i.p.), cyclooxygenase-2-like immunoreactive cells were found in the parenchymal and subarachnoidal blood vessels. In these blood vessels, the cyclooxygenase-2-like immunoreactivity was restricted to the perinuclear region of the endothelial cells as revealed by a laser confocal microscopy, double-immunofluorescence staining with an endothelial marker, and immunoelectron microscopy. On the other hand, the cyclooxygenase-2-like immunoreactive cells were distinct from microglia or perivascular/meningeal macrophages as revealed by double immunostaining with macrophage/microglia-specific antibodies. Cyclooxygenase-2-like immunoreactive cells were first found at 1.5 hr after the lipopolysaccharide injection, at which time the fever had not been developed. After that, the number of cyclooxygenase-2-like immunoreactive cells and fever followed a similar time course, both being highest at 5 hr after the lipopolysaccharide injection and both returning to the baseline by 24 hr. These results demonstrate that brain endothelial cells are the primary sites where the activation of arachidonic acid cascade takes place during fever after intraperitoneal injection of lipopolysaccharide.

Endogenous monocyte chemoattractant protein-1 recruits monocytes in the zymosan peritonitis model.

Abstract: The role of monocyte chemoattractant protein-1 (MCP-1) in the recruitment of blood-derived monocytes in a model of zymosan peritoneal inflammation was investigated. After zymosan injection (1 mg) a rapid influx of polymorphonuclear leukocytes (PMN) and monocytes into the peritoneal cavity associated with mouse MCP-1 (JE) gene activation and protein secretion in the exudates occurred. MCP-1 production (maximal at 4 h) preceded the accumulation of monocytes (F4/80-positive cells, maximally recovered between 16 and 24 h). Treatment of mice with a single injection of anti-mouse MCP-1 antibody inhibited 16-h monocyte accumulation by approximately 40%, however, a significant decrease in the number of PMN was also measured. Finally, intraperitoneal injection of murine recombinant MCP-1 (1 microg) produced a selective accumulation of monocytes (F4/80-positive cells) into the peritoneal cavity. In conclusion, we show the novel existence of a strict relationship between MCP-1 production and leukocyte accumulation in this model of acute inflammation.

Neutrophil and macrophage responses to inflammation in the peritoneal cavity of rainbow trout Oncorhynchus mykiss. A light and electron microscopic cytochemical study.

Abstract: The neutrophil and macrophage responses that accompany inflammation were studied in the peritoneal cavity of rainbow trout Oncorhynchus mykiss using light and electron microscopic cytochemistry. Neutrophils of inflammatory peritoneal exudates were alpha-naphthyl butyrate esterase-negative, peroxidase-positive and rich in cytoplasmic glycogen granules. Macrophages were poor in glycogen, esterase-positive and usually peroxidase-negative. Some peroxidase-positive macrophages were due to the transfer to macrophages of neutrophilic peroxidase. The ultrastructural double labelling for glycogen-peroxidase or esterase/peroxidase was most useful for precisely characterising neutrophils and macrophages in the inflamed peritoneal cavities and for correctly labelling peroxidase-positive macrophages. Intraperitoneal injection of casein, Incomplete Freund's Adjuvant (IFA) and live or formol-killed Yersinia ruckeri resulted in a rapid influx of neutrophils, peaking at 24 to 48 h post-injection and reaching values, in the case of live bacteria, 500 x those in the resting, unstimulated peritoneal cavity. Peritoneal macrophages also increased, but the response was slower (peak at 5 d) and with more modest increases in number (7.5 x). Neutrophil and mononuclear cells returned to normal values after 15 d in the case of casein and bacteria, but continued above base values 30 d after the injection of IFA. Conversely, after the injection of phosphate buffered saline, India ink or with sham-injections, very moderate neutrophil and and macrophage responses subsided in a few hours. Phagocytosis of bacteria was studied by light microscopy of preparations stained for peroxidase by a new method which allows for the simultaneous observation of intracellular bacteria and peroxidase staining. When Y. ruckeri was injected into resting peritoneal cavities, bacteria were ingested by the resident macrophages. When the bacteria were injected into cavities with high numbers of neutrophils (due to the previous injection of casein), more neutrophils than macrophages contained bacteria. Results show that the macrophages are the resident phagocytes of the peritoneal cavity of trout, while neutrophils are present in that body cavity in significant numbers only in situations of inflammation and only as long as the inflammation persists.

Acute and Subacute Toxicity Study of Water-Soluble Polyalkylsulfonated C60 in Rats

Abstract: Polyalkylsulfonated C60, or FC4S, a highly water-soluble caged fullerene derivative, is believed to be a free radical remover or an antioxidant in biological systems. A 50 mg/ml aqueous solution was prepared as a master solution and administered to female Sprague-Dawley CD(Crl:CDR (SD)BR) rats in a single-dose acute toxicity study or a 12-day subacute toxicity study where rats were given the solution daily. In a study of the median lethal dose (LD50), no rats died after oral administration, and thus FC4S was considered to nontoxic if administered orally. In an LD50 intraperitoneal injection study, rats died within 30 hr after injection; the LD50 was determined to be approximately 600 mg per kilogram of body weight. Rats injected with the compound intraperitoneally or intravenously immediately eliminated the compound through the kidney; the kidney appeared to be the primary target organ. The compound induced a distinct lysosome-overload nephrosis, a phagolysosomal nephropathy characterized by a tinctorial ...

Immune responses limit adenovirally mediated gene expression in the adult mouse eye.

Abstract: In order to investigate the immunological consequences of that the eye is not normally immune-privileged with respect gene transfer to the eye using viral vectors, adenovirus car- to viral vectors. Inflammatory cells were detected in the vitrying a lacZ reporter gene (AV.LacZ) was injected either reous after anterior chamber injection and in the retina after subretinally, subconjunctivally or into the anterior chamber subretinal injection of adenovirus. The presence of both of three groups of adult mice: immunocompetent or transi- CD4 + and CD8 + T cells was established by immunophenoently immunosuppressed BALB/c mice and congenic typing. Reinjection of BALB/c mice resulted in rapid decline immunodeficient nude mice. Adenovirally mediated lacZ in reporter gene expression, but successful readminisexpression persisted for approximately 3 weeks following tration was possible in the case of immunodeficient nude injection of the vector into the anterior chamber, retina or mice. However, after transient depletion of T cells, achieextra ocular tissues of the conjuctiva of BALB/c mice. It ved by intraperitoneal injection of both CD8- and CD4-speappears that T cell-mediated immune responses limit the cific antibodies, the duration of expression in BALB/c mice duration of AV-mediated ocular gene expression in adult was longer in the eye (at least 12 weeks, again with mice since lacZ gene expression was detected for at least decrease in level over time), than in extra-ocular tissues (8 15 weeks in T cell-deficient BALB/c nude mice, although weeks) provided the animal was not reinjected with virus, the level of transgene expression decreased with time. raising the possibility of partial ocular immune-privilege Since intra-ocular AV-mediated gene expression was not after transient immunosuppression. significantly longer than extra-ocular expression, it appears

The Influence of Apoptosis on Intestinal Barrier Integrity in Rats

Abstract: Background: Apoptosis is a critical step responsible for maintaining the cellular balance between proliferation and death and for controlling tumorigenesis. Although an increase in intestinal apoptotic cells has been considered to be associated with the pathogenesis of gastrointestinal injury, little is understood concerning the role of apoptosis in the development of intestinal barrier dysfunction. Methods: Apoptosis induced by intraperitoneal injection of doxorubicin in rats was evaluated by transmission electron microscopy and the TUNEL histochemistry method. Treatment with deoxy-D-glucose (a glycolytic pathway inhibitor) or cycloheximide (a protein synthesis inhibitor) was performed after doxorubicin challenge. Passage of human serum albumin from blood to the intestinal interstitium and the intestinal lumen or from the intestine to the intestinal interstitium and blood was evaluated by means of albumin clearance. Results: A significant increase in gut water content, albumin flux, and bidirectional cle...

Avidin Targeting of Intraperitoneal Tumor Xenografts

Abstract: Background: Lectins (proteins that bind specific sugar molecules on glycoproteins and glycolipids) are expressed at various levels on the surface of tumor cells. Conjugation of cytotoxic agents to glycoproteins recognized by lectins could be useful in the treatment of tumors. Avidin (a highly glycosylated, positively charged protein found in egg white) contains terminal N-acetylglucosamine and mannose residues that bind to some lectins. In this study, we tested the ability of avidin, labeled through conjugation to radioactive biotin (a B vitamin), to target intraperitoneal tumors. Methods : Biotin was radioactively labeled with 111 In. Four tumor models (one ovarian, one lung, and two colon) were established in nude mice by intraperitoneal injection of cultured cancer cells. The following two approaches were used in the intraperitoneal administration of avidin: 1) radioactive biotin-avidin conjugates were injected and 2) avidin was injected 1-24 hours before the injection of radioactive biotin (avidin pretargeting; avidin-biotin conjugates formed in vivo). The distribution of injected radioactivity in the tissues of treated animals was assessed. Results: Radiolabeled avidin localized highly and rapidly in the tumors. More than 50% of the administered dose of avidin-biotin conjugate accumulated per gram of tumor tissue 2 hours after injection; high tumor uptake of radioactivity was observed up to 24 hours after conjugate injection. In contrast, accumulation of radioactivity in normal tissues was low, yielding high tumor to nontumor ratios. With avidin pretargeting, accumulation of radioactivity in the liver, kidney, and spleen was reduced to a greater extent than that in the tumor, and tumor to nontumor ratios were increased. Conclusions: Avidin may be a promising vehicle for the delivery of radioisotopes, drugs, toxins, or therapeutic genes to intraperitoneal tumors.

Can cellular transplantation improve function in doxorubicin-induced heart failure?

Abstract: BACKGROUND Transplantation of fetal cardiomyocytes has been shown to improve function of regionally infarcted myocardium, but its effects on global heart failure are still unknown. METHODS AND RESULTS Heart failure was induced in female mice by intraperitoneal injection of doxorubicin (2 mg/kg twice per week over 2 cycles of 2 weeks separated by a 2-week drug-free period). One week after the end of treatment, left ventricular function was assessed by transthoracic echocardiography (baseline). Animals were then randomized into 3 groups: The treated group (n = 12) received an intramyocardial injection of fetal cardiomyocytes (1 x 10(6) in 10 microL) harvested from transgenic mice expressing the gene of beta-galactosidase, the control group (n = 15) received an equivalent volume of culture medium alone, and 10 sham mice had no surgery. Two weeks and 1 month after transplantation, function was again assessed echocardiographically. At baseline, fractional shortening was not significantly different between the 3 groups. It then significantly increased in cell-treated mice at 2 weeks and 1 month after transplantation (P < 0.002 and P < 0.03 versus baseline, respectively), whereas it did not change in untreated animals. Transplanted cells could not be identified by beta-galactosidase activity or presence of Y chromosome (with 1 exception). CONCLUSIONS Cellular transplantation can improve function of globally failing hearts by a mechanism that might not necessarily involve the sustained presence of transplanted cells but rather the effects of cardioprotective factors released by them.

Tumor necrosis factor-alpha as a contributor in fumonisin b1 toxicity

Abstract: Fumonisin B1 is a toxic product of Fusarium moniliforme, which inhibits ceramide synthase, leading to accumulation of free sphingoid bases. Despite its known biochemical action, the mechanism of toxicity is not fully understood. Male BALB/c mice were injected subcutaneously with 0 to 6.75 mg/kg/day of fumonisin B1 for 5 days. One day after the last treatment, spleens were collected, and peritoneal macrophages were obtained from separate groups after an intraperitoneal injection of thioglycolate broth. Peripheral leukocyte counts were increased and kidney weights were decreased by fumonisin B1 treatment. Presence of apoptotic cells in the liver and kidney of treated mice was confirmed by enzymatic immunoassay. Macrophages cultured with lipopolysaccharide indicated an increased secretion of tumor necrosis factor-alpha (TNF-alpha) but not of interleukin-1alpha. No effect was seen on interferon-gamma production when splenocytes were incubated with concanavalin A. Elevation of leukocyte and reticulocyte counts was abrogated by pretreatment with anti-TNF-alpha antibody before a single dose of fumonisin B1 (25 mg/kg), supporting the hypothesis that the fumonisin B1 toxicity involves TNF-alpha. Cultures of J774A.1 cells, when treated with fumonisin B1, produced TNF-alpha in vitro. Results indicate that fumonisin B1 toxicity may involve secretion of TNF-alpha by TNF-alpha-producing cells without altering interleukin-1alpha or interferon-gamma. The influence on TNF-alpha-production may be a contributing factor to fumonisin B1-induced apoptosis and other observed toxic effects in animals.

Suppression of the Granulocyte Colony‐Stimulating Factor Response to Escherichia coli Challenge by Alcohol Intoxication

Abstract: Alcohol's suppressive effects on polymorphonuclear leukocyte (PMN) production and function increases host susceptibility to a wide variety of infections and impairs the ability of these effector cells to seek and destroy invading pathogens. Granulocyte colony-stimulating factor (G-CSF), an important regulator of PMN production and function, is known to be increased in the plasma during infectious episodes. In previous studies we found acute alcohol intoxication to suppress the tumor necrosis factor-alpha (TNF alpha) response to in vivo challenges with bacteria or lipopolysaccharide. The present study was initiated to determine the impact of alcohol intoxication on the plasma G-CSF response to gram-negative infection. For this purpose, rats received an intravenous challenge of Escherichia coli (10(6) CFU) 30 min after an intraperitoneal injection of ethanol (5.5 g/kg) or an equivalent volume of saline (control). Ethanol-intoxicated rats had a greater 48 hr mortality to live E. coli injection than did unintoxicated animals (45% vs. 8%). Despite an increased bacterial burden in both the lung and liver at 24 hr after initiating E. coli infection in alcohol-intoxicated animals, PMN tissue recruitment, indexed as myeloperoxidase activity, did not differ between control and alcohol-treated rats. Moreover, alcohol suppressed blood PMN phagocytic capacity to a greater extent in animals given alcohol than controls at 5 and 24 hr after initiating infection. In control animals after intravenous E. coli injection, bioactive G-CSF increased in plasma and peaked near 300 ng/ml at 8 hr. In rats pretreated with alcohol, the plasma G-CSF response was markedly suppressed in response to intravenous E. coli (p < 0.05). In a second experiment, neutralization of the E. coli-induced plasma TNF alpha response by pretreatment with anti-TNF alpha antibody similarly inhibited the plasma G-CSF response. These results support the postulate that alcohol-induced inhibition of TNF alpha directly contributes to the adverse effects of alcohol on PMN function by suppressing the normal autocrine amplification pathway responsible for G-CSF production.

Acute ethanol intoxication inhibits neutrophil beta2-integrin expression in rats during endotoxemia.

Abstract: The effects of acute ethanol intoxication on neutrophil [polymorphonuclear leukocyte (PMN)] adhesion molecule expression and certain other functional properties during endotoxemia were studied in rats to elucidate the mechanisms underlying the immunosuppressive effects of ethanol. Acute ethanol intoxication was induced by an intraperitoneal injection of 20% ethanol at a dose of 5.5 g of ethanol/kg. Control animals received an intraperitoneal injection of saline. Thirty minutes after intraperitoneal injection, animals were given a 90-min intravenous infusion of Escherichia coli endotoxin (total dose of 112.5 microg/rat in 2.5 ml of saline) or saline. Certain rats received granulocyte colony-stimulating factor (G-CSF; 50 microg/kg in 5% dextrose, subcutaneous injection twice daily) or vehicle pretreatment for 2 days before intravenous endotoxin infusion. Endotoxemia significantly upregulated CD11b/c and CD18 expression on PMNs when compared with those of saline-infused rats. Acute ethanol intoxication inhibited this endotoxin-induced upregulation of CD11b/c and CD18 expression on PMNs. Ethanol intoxication also suppressed the phagocytic activities of PMNs in saline-infused rats, but this suppression failed to reach statistical significance in endotoxin-infused rats. Hydrogen peroxide generation by PMNs in saline- or endotoxin-infused rats was not affected by ethanol intoxication. Histological examination showed extensive PMN sequestration in the liver after endotoxin infusion, and ethanol intoxication significantly attenuated this hepatic sequestration of PMNs. G-CSF pretreatment enhanced neutrophil phagocytosis, CD11b/c and CD18 expression in endotoxin-infused rats, and prevented the ethanol-induced inhibition of neutrophil CD18 expression and phagocytosis. The impairment of beta2-integrin expression on PMNs may be one mechanism underlying ethanol-induced defects of neutrophil delivery into tissue sites of infection. G-CSF may be of benefit to the infected alcoholic host by enhancing leukocyte defense functions.

Interleukin-4 and interleukin-10 are chondroprotective and decrease mononuclear cell recruitment in human rheumatoid synovium in vivo.

Abstract: We used the severe combined immunodeficient (SCID) mouse model to assess the effect of interleukin-4 (IL-4) or IL-10 injection on cartilage degradation and mononuclear cell (MNC) recruitment to human rheumatoid synovium in vivo. Human rheumatoid synovium and cartilage from five rheumatoid arthritis patients, obtained after joint replacement surgery, were engrafted subcutaneously to 6-8-week-old SCID CB17 mice. Synovial tissues were injected with recombinant human IL-4 (rhIL-4, 100 ng; rhIL-10, 100 ng), both cytokines, or tumour necrosis factor-alpha (TNF-alpha) (1000 U), or phosphate-buffered saline twice a week for 4 weeks. The graft was removed and immunochemical analysis was carried out to assess intracellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1) and E-selectin expression. Moreover, cartilage degradation was assessed through the quantification of the erosion surface on a computerized image of the engrafted cartilage at high power view. MNC recruitment in the synovial tissue was determined by labelling blood MNC with indium-111 before their intraperitoneal injection. The activity obtained in the region of the graft were determined with a gamma camera 72 hr postinjection. The results are expressed as a percentage of initial injected activity. After 4 weeks we observed a decrease of cartilage area in controls (77 +/- 8%), inhibited after injection of IL-4, IL-10, or both cytokines (90 +/- 3%, 89.1 +/- 4%, 89.2 +/- 5% respectively), and 57 +/- 17% after TNF-alpha injection. The % MNC activity in the graft decreased to 77 +/- 81% (NS), 9 +/- 4% (P < 0.003) and 19 +/- 6% (P < 0.007) compared with untreated synovial tissue after treatment with IL-4, IL-10, or both cytokines, respectively. Moreover, IL-10 but not IL-4 decreased the expression of ICAM-1 but not VCAM-1 or E-selectin by synovial cells. These results suggest that IL-10 and IL-4 could have chondroprotective properties, and that IL-10 but not IL-4 inhibits MNC traffic towards the synovial tissue efficiently.

Acute osmotic/stress stimuli induce a transient decrease of transcriptional activity in the neurosecretory neurons of supraoptic nuclei.

Abstract: Administration of hypertonic NaCl solutions by intraperitoneal injection evokes a transient expression of immediate-early genes in the hypothalamic magnocellular neurons of supraoptic nuclei (SON), which is followed by an upregulation of arginine vasopressin synthesis and a general increase in cellular metabolic activity. Here we have analysed the changes that occur in the nucleus of SON neurons during the period of transient Fos expression after injection of hypertonic saline. Within the first 30 minutes after injection, the nuclei become significantly smaller, contain more condensed chromatin and incorporate less 3H-uridine than the controls. By 12 hours these effects are reverting and at 24 hours the nuclei are already more active than the controls. Additionally, we observe an initial decrease in the number of coiled bodies per nucleus within the first 2 hours, followed by a 3-fold increase at 24 hours after injection. As coiled bodies are transcription-dependent subnuclear 'organelles', these results further support the view that injection of hypertonic saline causes a transient inhibition of nuclear activity. Our data show that SON neurons respond to acute osmotic/stress stimuli first with inhibition and then with activation of gene expression. Importantly, inhibition of transcriptional activity occurs simultaneously with maximal accumulation of Fos protein in the nucleus, raising the possibility that activation of c-fos expression may cause repression of target genes.

Detection of nivalenol genotoxicity in cultured cells and multiple mouse organs by the alkaline single-cell gel electrophoresis assay

Abstract: We tested the genotoxicity of nivalenol (NIV), a potent toxic trichothecene from Fusarium nivale, in cultured CHO cells and in several mouse organs and tissues (liver, kidney, thymus, bone marrow and mucosa of stomach, jejunum, and colon) using the alkaline single-cell gel electrophoresis (SCG, or Comet) assay. NIV at 50 and 100 micrograms/ml damaged the nuclear DNA of CHO cells in the absence of S9 mix, showing that NIV was a direct mutagen. In an in vivo study, mice were sacrificed 2, 4, and 8 h after either oral (20 mg/kg) or intraperitoneal (3.7 mg/kg) administration of NIV. DNA damage was measured by the SCG assay as modified by us. After oral dosing, DNA damage appeared in the kidney and bone marrow at 2 h (returning to almost control level within the following 2 h), and in the stomach, jejunum, and colon at 2, 4, and 8 h, respectively. Liver and thymus DNA were not damaged. After intraperitoneal injection, no DNA damage appeared in any of the organs or tissues tested except for the colon, where extensive DNA damage was observed, as in the oral study, at 8 h. For histopathological examination, mice were sacrificed 2, 4, and 8 h after oral (20 mg/kg) administration of NIV. No necrotic changes were detected in any of the organs where NIV yielded statistically significant DNA damage. To measure the effect of NIV on transport activity in mice, 10 ml/kg (same volume as NIV treatments) of 1% brilliant blue FCF (BB) was administered orally. Thirty minutes later, the BB reached the colon, and simultaneous oral administration of NIV (20 mg/kg, dissolved in 10 ml BB solution) did not affect the dye transport rate. Thus, the strong yet delayed damage to colon DNA may follow from a systemic absorption rather than a topical effect. As a direct mutagen, NIV showed organ specific genotoxicity in mice in time and intensity.

Oral delivery of micro-encapsulated DNA vaccines.

Abstract: Oral delivery of vaccines is an attractive alternative to injection. It is a non-invasive procedure which allows access to the gut-associated lymphoid tissues (GALT). Immunisation at GALT results in mucosal immune responses, which may be of particular importance in protection against infection at mucosal surfaces, as well as systemic immune responses. Vaccine antigens can be protected in the gut by encapsulation in poly(DL-lactide-co-glycolide) (PLG) microparticles. Their uptake into the immune inductive tissues of the GALT is mediated by M cells, which selectively phagocytose particles less than 10 microns in diameter. We have developed a method for the PLG encapsulation of plasmid DNA. Encapsulated DNA, expressing the insect protein luciferase under the transcriptional control of the human cytomegalovirus immediate early promoter, was administered to mice by intraperitoneal injection or oral gavage. Intraperitoneal injection of encapsulated DNA elicited good serum IgG and IgM responses and a modest IgA response. Oral administration stimulated good serum antibody titres in all three classes, and in addition, significant levels of mucosal IgA. PLG encapsulation thus has the ability to protect plasmid DNA against degradation after administration, and to facilitate its uptake into appropriate cells for the subsequent expression and presentation of antigen, in such a way as to elicit both systemic and mucosal antibody responses. This may have major implications for the design of novel vaccines and delivery strategies.

Arrested Maturation of Granulocytes in Copper Deficient Mice

Abstract: The objective of this study was to examine the role of copper in neutrophil development and function. Mice were made copper deficient by feeding dams a diet containing 1.05 microg copper starting at parturition. Control mice were fed the same diet containing 6 microg copper. The pups were weaned to the diet and killed when they were 5-6 wk old. Peripheral blood cell counts, margination and cell maturity were measured. The response to an intraperitoneal injection of lipopolysaccharide (LPS) was also determined. Copper deficiency resulted in twice as many neutrophils and fewer than half the number of lymphocytes. Half as many cells in copper-deficient mice expressed Ly-6G, a granulocytic marker of cell maturity. In addition, copper-deficient cells expressed only half the amount of Ly-6G per cell than was expressed by copper-adequate cells. This suggested that the cells were younger, or arrested in their maturation as a result of copper deficiency. An arrest of maturation has been proposed as the cause of neutropenia in human copper deficiency. Injection of LPS in copper-adequate mice resulted in twice as many Ly-6G-expressing cells in the periphery. LPS injection into copper-deficient mice resulted in a severe leukopenia but did not influence Ly-6G expression any more than did copper deficiency alone. LPS treatment caused an increase in myeloperoxidase activity associated with the lungs of copper-deficient mice. The results suggest that although the neutrophils of copper-deficient mice are immature, they can be sequestered by the lung when stimulated to do so.

Increased mortality, blunted production of nitric oxide, and increased production of TNF-alpha in endotoxemic TGF-beta1 transgenic mice.

Abstract: The expression of the inducible isoform of nitric oxide synthase (NOS2, iNOS) is increased in patients undergoing sepsis as well as in animal models in which septic shock is induced by injection of bacterial lipopolysaccharide (LPS). Transforming growth factor-beta1 (TGF-beta1) potently suppresses NO production both in vitro and in vivo. After intraperitoneal injection of LPS, mice over-expressing a cDNA coding for active TGF-beta1 in the liver (Alb/ TGF-beta1) exhibited reduced serum levels of the NO reaction products NO2(-) + NO3(-) compared with controls. Paradoxically, while endotoxemic Alb/ TGF-beta1 mice expressed much less NOS2 protein in peritoneal exudate cells than did endotoxemic wild-type mice, Alb/TGF-beta1 mice expressed more NOS2 mRNA and protein in both liver and kidney. Alb/ TGF-beta1 mice treated with LPS had eightfold higher serum tumor necrosis factor alpha (TNF-alpha) levels and experienced increased mortality compared with wild-type mice, which was associated with renal insufficiency. These results suggest that renal dysfunction, decreased production of NO, and/or increased production of TNF-alpha are associated with increased mortality of endotoxemic Alb/TGF-beta1 mice.

Contrasting effects of an aminobisphosphonate, a potent inhibitor of bone resorption, on lipopolysaccharide‐induced production of interleukin‐1 and tumour necrosis factor α in mice

Abstract: 1 Aminobisphosphonates (aminoBPs), potent inhibitors of bone resorption, have been reported to induce inflammatory reactions such as fever and an increase in acute phase proteins in human patients, and to induce the histamine-forming enzyme, histidine decarboxylase, in mice. In the present study, we examined the effect of aminoBP, 4-amino-1-hydroxybutylidene-1,1-bisphosphonic acid (AHBuBP), on the production of the pro-inflammatory cytokines, IL-1 and TNFα, in mice. 2 Intraperitoneal injection of AHBuBP did not itself produce detectable levels of IL-1 (α and β) and TNFα in the serum. However, the elevation of serum IL-1 induced by lipopolysaccharide (LPS) was greatly augmented in mice injected with AHBuBP 3 days before the LPS injection, whereas the LPS-induced elevation of serum TNFα was almost completely abolished. 3 Spleen and bone marrow cells taken from mice injected with AHBuBP produced IL-1β in vitro spontaneously, and the production was augmented following the addition of LPS. Cells that accumulated in the peritoneal cavity in response to AHBuBP produced a particularly large amount of IL-1β. However, AHBuBP treatment of mice did not lead to an impairment of the in vitro production of TNFα by these three types of cells. 4 Liposomes encapsulating dichloromethylene bisphosphonate (a non-amino BP) selectively deplete phagocytic macrophages. When an intraperitoneal injection of these liposomes was given 2 days after an injection of AHBuBP, there was a marked decrease in the LPS-induced elevation of serum IL-1 (α and β) (LPS being injected 3 days after the injection of AHBuBP). 5 These results indicate that AHBuBP has contrasting effects on the in vivo LPS-induced production of IL-1 and TNFα in mice, enhancing the production of IL-1 by phagocytic macrophages and suppressing the production of TNFα, although underling mechanisms remain to be clarified. British Journal of Pharmacology (1998) 125, 735–740; doi:10.1038/sj.bjp.0702151

Effects of endotoxic shock in several functions of murine peritoneal macrophages.

Abstract: Gram negative sepsis and septic shock continue to be a major medical problem, with a complex physiopathology and it is associated with high mortality. Although secretion of cytokines such as tumor necrosis factor-alpha by macrophages is the principal host mediator of septic shock, other characteristic functions of macrophages implicated in their phagocytic capacity have not been studied in the process of endotoxic shock. In the present study we have used an intraperitoneal injection of E. coli lipopolysaccharide (LPS) (100 mg/kg) in order to obtain an endotoxic shock model in adult female BALB/c mice. Peritoneal cell suspensions were obtained at several times (2, 4, 12 or 24 h) after injection and the following functions were studied on the peritoneal macrophages: adherence to substrate, mobility (spontaneous and directed or chemotaxis), ingestion of particles and superoxide anion production. The results showed a stimulation of adherence, ingestion and superoxide production as well as a decrease of chemotaxis in the animals injected with LPS. These effects changed with time after LPS injection. Thus, the increase of adherence and the decrease of mobility were higher during the first hours, whereas the increase in ingestion and superoxide production turned larger with time.

Pretreatment of Young Pigs with Vitamin E Attenuates the Elevation in Plasma Interleukin-6 and Cortisol Caused by a Challenge Dose of Lipopolysaccharide

Abstract: The effect of a short-term, high-dose intramuscular injection of d-alpha-tocopherol was studied in pigs given a challenge dose of lipopolysaccharide (LPS). Twenty-four pigs surgically fitted with jugular catheters were used in a 2 x 2 factorial design. Pigs received either 0 or 600 mg d-alpha-tocopherol by intramuscular injection for 3 d before receiving an intraperitoneal injection of saline containing either 0 or 5 microgram/kg body weight Escherichia coli LPS. Blood was collected from indwelling jugular catheters at 0, 1, 2, 4, 6, 8, 12 and 24 h after injection of LPS. Plasma alpha-tocopherol levels were 13-fold greater (P < 0.01) at time 0 in pigs pretreated with 600 mg d-alpha-tocopherol (9.9 +/- 1.3 mg/L) than in those not treated with d-alpha-tocopherol (0.74 +/- 0.09 mg/L). Injection of LPS increased (P < 0.05) plasma levels of interleukin-6 (IL-6) and cortisol at 2-h postinjection, regardless of vitamin E treatment. However, pigs that received alpha-tocopherol before the LPS challenge had substantially lower (P < 0.05) peak levels of IL-6 and cortisol than pigs not receiving alpha-tocopherol. These results suggest that supplementation with a surfeit level of vitamin E reduces the response of pigs to endotoxin.

Tissue distribution and cellular uptake of Aeromonas salmonicida lipopolysaccharide (LPS) in some marine fish species

Abstract: Αbstract Τhe uptake and distribution of lipopolysaccharide (LPS), isolated from Aeromonas salmonicida, was investigated in Atlantic cod, Gadus morhua L, turbot, Scophthalmus maximus L, and Atlantic halibut, Hippoglossus hippoglossus L LPS was radiolabelled by bromine oxidation and subsequent sodium borotritide reduction (3H-LPS), and fluorescence-labelled by introducing a fluorescein isothiocyanate derivative (FITC-LPS) After intravenous and intraperitoneal injections in cod, high amounts of radioactive LPS (3H-LPS) were present in heart, spleen and kidney throughout the experimental period (1–168 h) After peroral administration, a high amount of 3H-LPS was observed in intestinal tissues, whereas internal organs and tissues contained considerably lower amounts Following intravenous administration of 3H-LPS in turbot, high contents of radioactivity were revealed in spleen, liver and kidney, whereas the content in heart was lower than in blood at the sampling times (1–24 h) The same pattern was observed after intraperitoneal administration The spleen and liver contained high amounts of radioactivity when the turbots were intubated perorally with 3H-LPS The spleen, kidney and heart were the main scavenging organs following intravenous administration of 3H-LPS in Atlantic halibut A minor amount of radioactivity was present in the liver The same pattern emerged after intraperitoneal injection in halibut As observed for turbot, the spleen was the main accumulation site for 3H-LPS following peroral administration Fluorescence microscopy of sections of organs and tissues from cod, intravenously and intraperitoneally injected with FITC-LPS, revealed that endocardial cells of both atrium and ventricle contained large amounts of the fluorochrome, whereas in turbot and halibut only atrial endothelial cells accumulated the substance In all species, macrophages in kidney and spleen contained FITC-LPS and in the spleen the fluorochrome was trapped in the ellipsoidal walls At later time points (eg 48 h) in the turbot spleen, FITC-LPS was located in cells adjacent to the ellipsoidal walls Halibut endothelial cells that were located in the connective tissue of the intestine and gills also contained FITC-LPS After peroral administration to the different fish species, specific fluorescence was found only in intestinal epithelial cells of halibut and in cells located in the lamina propria Fluorescence was not detected in internal organs such as the kidney, spleen and liver after peroral administration of FITC-LPS Gel chromatographic analysis of plasma samples from cod, turbot and halibut after intravenous and intraperitoneal injections showed that high molecular weight radioactivity was present A minor amount of radioactivity that corresponded to low molecular weight substances was also observed In conclusion, there is a high degree of variation with respect to the site of accumulation and some variation in the type of cells involved in the uptake of purified LPS in cod, turbot and halibut

Selective delivery of 10b to soft tissue sarcoma using 10B-L-borophenylalanine for boron neutron capture therapy

Abstract: Boron neutron capture therapy (BNCT) may improve the locoregional control of radio/chemoresistant tumours like soft tissues sarcomas (STS). This technique uses the 10B(n,alpha)7Li nuclear reaction to destroy tumour cells, provided that a sufficient amount of 10B may be carried selectively into them. In order to evaluate the targeting potential of 10B-L-borophenylalanine (BPA) a 10B biodistribution study was carried out in 24 Wistar rats bearing Yoshida sarcoma. Six animals received increasing intraperitoneal doses of BPA (300, 600 and 1200 mg kg-1), while the remainder received a BPA dose of 600 mg kg-1 but with a sacrifice at six different time points: 1, 2, 4, 6, 9 and 12 h. The 10B concentrations in the tumours, normal tissues and blood were analysed with neutron capture radiography (NCR). The analysis shows that 36 micrograms g-1 (+/- 4 SD) of 10B may be incorporated into the tumour, with a ratio of 13 (+/- 4 SD) versus the muscle and a ratio of 15 (+/- 3 SD) versus the blood, 6 h after an intraperitoneal injection of 600 mg kg-1 of BPA. The BPA appears to be abundantly incorporated in the tumour, and the kidney proximal tubule area. These data suggest that BNCT using BPA may provide an improved therapeutic ratio for the treatment of STS.