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At least 811 records · Page 45Linked to original sources
PubMed1986

Pyrogenic and haematological effects of the interferon-inducing 22K factor (interleukin 1 beta) from human leukocytes.

Human 22K factor is a cytokine released by mitogen-stimulated peripheral blood leukocytes. The factor stimulates fibroblasts to produce interferon-beta (IFN-beta) and thereby exerts antiviral activity on these cells. It was identified as interleukin-1 beta (IL-1 beta) by its amino-acid sequence and spectrum of biological activities. The pyrogenic and haematological effects of pure 22K factor were studied at different doses and were compared with those of endotoxin and interferon. 22K factor dose-dependently induced fever in rabbits, 0.1 microgram/kg being a minimum effective dose. Intravenous injection in rabbits caused immediate granulocytosis at low dose, while a profound granulopenia followed by hypergranulocytosis was observed at high dose. Preparations of pure 22K factor were free of detectable lipopolysaccharide and lost their biological effects after heat-treatment. Repeated injections of 22K factor did not result in a state of tolerance. There is no evidence that the effects in vivo of 22K factor were mediated by induction of interferon. Human 22K factor, a weak and species-specific inducer in IFN-beta in vitro, did not induce detectable amounts of circulating interferon in rabbits. Moreover, injection of rabbits with IFN-beta resulted in a weak effect on body temperature and granulocyte counts as compared to similar doses of 22K factor.

Agranulocytosis↗
PubMed1986

[Detection of endotoxins in radiopharmaceutical preparations--III. Limulus test assessment using radiopharmaceutical preparations; correlation with the rabbit pyrogen test].

Experiments using 17 radiopharmaceuticals containing known amounts of added endotoxin show that none of them inhibits the pyrogenic reaction of the rabbit. Gelation of the Limulus amoebocyte lysate (LAL) is inhibited by 4 of them: colloidal erbium 169Er citrate, colloidal rhenium 186Re sulfide, colloidal technetium 99mTc (Re) sulfide for liver scintigraphy and the colloidal technetium 99mTc (Re) sulfide for lymphography. This inhibition is cancelled, either by dilution or after neutral pH adjustment. Both controls were performed on 313 batches of various radiopharmaceuticals, 95% of results were identical (93% negative, 2% positive). The remaining 5% correspond to positive LAL tests vs negative rabbit tests on the same batches. No negative LAL test vs positive rabbit test was observed.

Animals↗
PubMed1985

[Comparative analysis of the use of levamisole and pyrogenal in the treatment of multiple sclerosis].

A series of 120 patients with multiple sclerosis was subjected to a clinico-immunological examination and treatment. In a group of patients receiving levamisole, improvement of the neurologic symptomatology was observed in 65% of the cases and that of the immunological indices in 97.5%. Pyrogenal treatment led to no improvement in the immunological parameters. Clinical improvement in this group was seen in only 17.8% of the patients. It is recommended that treatment with levamisole be conducted following the preliminary assessment of the sensitivity of the patient's lymphocytes to the drug in vitro.

Adolescent↗
PubMed1985

Migration of isolated rabbit lymphocytes in the course of pharmacological inhibition of pyrogenic fever.

The studies concerned in vitro migration of peripheral blood lymphocytes of rabbits given intravenously one dose of E. coli lipopolysaccharide (LPS) and antipyretic doses of acetylsalicylic acid (ASA), indomethacin (IND) or mefenamic acid (MEFA). In normothermic animals, ASA appeared to inhibit in vitro the spontaneous migration of lymphocytes. Contrary to ASA, MEFA and IND did not produce any significant changes in lymphocytes migration. Four hours after pyrogen injection migration of lymphocytes was slightly enhanced and after 24 h it was significantly inhibited. All non-steroid anti-inflammatory drugs examined counteracted this effect.

Animals↗
PubMed1979

A new leptospiral serovar in The pyrogenes serogroup.

A new leptospiral serovar in the Pyrogenes serogroup is described. Parallel investigations by the 'classical' cross-agglutinin absorption test method and the 'factor analysis' method determined the serological properties of the new serovar. The serovar name kwale with reference strain Julu is proposed.

Adolescent↗
PubMed1983

The role of interleukin 1 in human B cell activation: inhibition of B cell proliferation and the generation of immunoglobulin-secreting cells by an antibody against human leukocytic pyrogen.

The role of factors released by monocytes (M phi) in the activation of human B lymphocytes was examined by studying the effect of an antiserum against human leukocytic pyrogen (LP) on mitogen-stimulated B cell proliferation and the generation of immunoglobulin-secreting cells (ISC) by peripheral blood mononuclear cells (PBM). Antiserum against LP was obtained from rabbits immunized with LP-containing human M phi supernatants. The globulin fraction of this antiserum inhibited pokeweed mitogen- (PWM) stimulated B cell proliferation and the generation of ISC in a concentration-dependent manner, with 50% inhibition of responsiveness observed with 10 micrograms/ml. By contrast, PWM-induced T cell [3H]thymidine incorporation was not inhibited by concentrations of anti-LP as great as 2000 micrograms/ml. The F(ab')2 fraction of anti-LP also inhibited the generation of ISC in response to both PWM and formalinized Staphylococcus aureus, but required 50 micrograms/ml to achieve 50% inhibition. Anti-LP inhibited the generation of ISC only if present during the first 24 hr of a 6 to 7-day incubation; later addition was not inhibitory. Inhibition was more marked in cultures partially depleted of M phi than in whole PBM cultures. Whereas absorption of the anti-LP with PBM failed to remove the capacity to inhibit the generation of ISC, anti-LP-mediated inhibition of responsiveness could be reversed by the addition of crude M phi culture supernatants or a variety of highly purified interleukin 1 (IL 1) preparations, but not by T cell supernatants. These results indicate anti-LP inhibits human B cell activation by removing the requisite M phi-derived factor IL 1 and also confirm that IL 1 plays an essential role in B cell proliferation and the generation of ISC in man.

Animals↗
PubMed1981

Affinity purification of alpha-galactosidase A from human spleen, placenta, and plasma with elimination of pyrogen contamination. Properties of the purified splenic enzyme compared to other forms.

The substrate analog alpha-D-galactosylamine was synthesized, linked to 6-aminohexanoic acid, and coupled to carboxyhexyl-Sepharose. This affinity support permitted the purification of human alpha-galactosidase A (alpha-D-galactoside galactohydrolase, EC 3.2.1.22) from spleen, placenta, and plasma. When used in conjunction with conventional procedures, affinity chromatography enabled the rapid and specific purification of alpha-galactosidase A from each source. Significantly, pyrogenic endotoxins were eliminated from enzyme preparations by the use of the affinity column. Splenic alpha-galactosidase A was purified in high yield (38%) with a specific activity of 1.9 X 10(6) units/mg. The purified enzyme was a homodimer with a native molecular weight of 101,000 and a subunit weight of 49,800. The UV absorption coefficient was E280 1% = 18 and the lambda max was 282 nm. The plasma form was purified with a markedly improved yield to a specific activity (229,000 units/mg) which was 3 times greater than that achieved previously. The enzymes from plasma, spleen, and placenta were immunologically identical. The physical and kinetic properties of the purified enzymes were consistent with and confirmed previous findings.

Carbohydrates↗
PubMed1984

Control of protein degradation in muscle by prostaglandins, Ca2+, and leukocytic pyrogen (interleukin 1).

Protein degradation in skeletal muscle increases with fever and sepsis. Our studies indicate that prostaglandin E2 (PGE2) is an important regulator of muscle proteolysis that seems to signal this increase in fever. When rat skeletal or cardiac muscles were incubated with arachidonate, rates of protein breakdown rose and protein balance became more negative. Aspirin or indomethacin, which prevented synthesis of PGE2, markedly reduced this effect. By itself PGE2 stimulated proteolysis without altering protein synthesis. PGE2 seems to increase proteolysis in the lysosomes, inasmuch as leupeptin and Ep-475 inhibit this response. These inhibitors inactivate lysosomal thiol proteases in the muscles without affecting the Ca2+-activated protease. (In fact, complete inactivation of the latter enzyme with mersalyl did not reduce overall proteolysis in the muscles). When muscles from feverish rats were incubated in vitro, they showed greater protein breakdown and PGE2 synthesis than muscles from normal animals. Addition of indomethacin eliminated this difference. Leukocytic pyrogen (interleukin 1), a protein released by monocytes that signals the onset of fever, also seems to signal increased muscle PGE2 synthesis and muscle proteolysis. This protein enhanced both processes dramatically in the isolated muscles. These findings suggest that cyclooxygenase inhibitors may be useful in the treatment of patients showing excessive protein breakdown.

Animals↗
PubMed1994

Changes in the ultrastructure and functions of immunocompetent cells under the influence of external heating, interleukin 1 beta and leukocytic pyrogen.

The structural and functional organization of the rabbit immunocompetent cells after injection of human recombinant interleukin 1 beta (IL-1 beta), partially purified leukocytic pyrogen (LP), or after external heating (36 degrees C, 1.5 h) was compared. A rectal temperature increase being the same, there were similar and transient changes in epithelial and endothelial cells and macrophages, a rise in the proliferative activity of thymocytes and synthesis of IL-1-like activity, and a decrease in the interleukin 2 (IL-2) production by cultured splenic cells.

Animals↗
PubMed1994

Proteolytically active streptococcal pyrogenic exotoxin B cleaves monocytic cell urokinase receptor and releases an active fragment of the receptor from the cell surface.

Urokinase plasminogen activator (u-PA) receptor (u-PAR) is a glycosyl-phosphatidylinositol-anchored membrane protein that promotes pericellular proteolysis and cellular migration. This investigation demonstrates that u-PAR is a substrate for the proteolytically active form of streptococcal pyrogenic exotoxin B (SPE B), a potent virulence factor secreted by Streptococcus pyogenes. Treatment of U937 monocyte-like cells with SPE B decreased specific 125I-labeled single-chain u-PA binding by up to 85%. Cysteine proteinase inhibitors neutralized SPE B without affecting the activity of phosphatidylinositol-specific phospholipase C. Due to decreased u-PA binding, SPE B-treated U937 cells expressed decreased activity against a u-PA-specific fluorogenic substrate and plasminogen. SPE B released single-chain u-PA that was noncovalently bound to U937 cells or cross-linked to cellular receptors with bis(sulfosuccinimidyl) suberate. The mass of the released u-PA-receptor complex was 100 kDa. Western blot analysis confirmed that the u-PA receptor that was cleaved by SPE B is u-PAR. After deglycosylation, the mass of SPE B-released u-PAR was 35 kDa, slightly smaller than the phosphatidylinositol-specific phospholipase C-derived form of this receptor. SPE B-released u-PAR retained the ability to bind u-PA, as determined by u-PA affinity chromatography. We conclude that SPE B may inhibit u-PA binding to monocytic cells by at least two mechanisms: (i) by decreasing the level of functional cell surface u-PAR and (ii) by releasing a soluble form of u-PAR that competes with the cellular receptor for ligand.

Bacterial Proteins↗
PubMed1993

The effect of Tołpa Peat Preparation on the phagocytic and metabolic activity of neutrophils in normothermic rabbits and with pyrogen-induced fever.

The studies on normothermic rabbits show that intravenous administration of Tołpa Peat Preparation (TPP) at a dose of 5 mg/kg for 3 or 6 consecutive days increases the percentage of phagocytizing cells and the number of bacteria phagocytized by a single neutrophil. The stimulated phagocytic activity of neutrophils coincides with increased nitroblue tetrazolium (NBT) reduction. In contrast, a single administration of TPP to rabbits with fever induced by E.coli lipopolysaccharide (LPS) has a modulating effect on the metabolic activity of neutrophils, depending on TPP dose. TPP administered at a dose of 0.5 mg/kg potentiates the stimulating effect of pyrogen on the percent of NBT-positive neutrophils. A tenfold increase of TPP dose (5 mg/kg) reduces the stimulating effect of LPS and a hundredfold increase (50 mg/kg) leads to total inhibition of LPS-induced changes.

Amino Acids↗
PubMed1997

Streptococcal pyrogenic exotoxin A, streptolysin O, exoenzymes, serotype and biotype profiles of Streptococcus pyogenes isolates from patients with toxic shock syndrome and other severe infections.

The determination of protein M and T serotypes, biotypes and pyrogenic (erythrogenic) exotoxin A (SPE A), streptolysin O (SLO), streptokinase (SK), hyaluronidase (HA) and cysteine proteinase release by 212 S. pyogenes isolates from patients with severe invasive group A streptococcal (GAS) infections, among them 74 cases of streptococcal toxic shock syndrome (STSS) has been investigated. M1 or M3 serotypes were expressed by 25% of the isolates (53/212), whereas 59% (125/212) belonged to 15 other different serotypes and 16% (34/212) were untypeable. Of the 74 isolates from STSS patients, 42% (31/74) expressed M1 and to a lesser extent M3 serotypes versus 19% of the non STSS isolates (26/138). Among the ten different biotypes known, biotypes 1 and 3 were prevalent, particularly the former in the case of STSS isolates. SPE A was detectably produced by about 25% (54/212) of the strains. However, as high as 40.5% of the STSS isolates (30/74) versus 17.4% of non STSS isolates (24/138) released SPE A. Moreover, 67% of the SPE A producing strains were of serotype M1 or M3. SK and HA were released by 71% and 10% of the isolates respectively. All strains released SLO (4 to 256 HU/ml) and 85% cysteine proteinase. No relationship between toxin or enzyme titer and the type of disease or clinical origin of the strains was found. Culture supernatants of all isolates showed moderate to high lymphocyte transforming activity with index values ranging from 14.5 to 50.3 including those strains which did not release detectable amounts of SPE A suggesting that SPE C and other mitogenic factor(s) are released by the isolates investigated.

Adolescent↗