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Adhesion of coagulase-negative staphylococci and adsorption of plasma proteins to heparinized polymer surfaces.

Protease treatment of cells of coagulase-negative staphylococci reduced the adhesion of bacteria to heparinized polyethylene preadsorbed with serum. Fibronectin (Fn), fibrinogen (Fg), vitronectin, complement factor C3c, plasminogen, laminin and to a low extent albumin were detected on tridodecylmethylammonium chloride (TDMAC)-heparinized polyvinyl chloride (PVC) catheters extirpated from the circulation of patients. Using a perfusion model we show that during the first hours of perfusion with human plasma, Fn and Vn dominate, whereas after 22 h of perfusion Fg is the dominant protein. Field emission scanning electron microscopy and atomic force microscopy studies on TDMAC-heparinized catheters as well as on end-point attached heparinized PVC catheters indicate that quantitatively more Fg than Fn is exposed on these surfaces after prolonged exposure (> 22 h) to human plasma.

Adsorption↗

A potential vaccine for cocaine abuse prophylaxis.

Presently, there are estimated to be 1.5 to 2.0 million individuals infected with HIV-1 in the U.S. and about 12 million worldwide. In the U.S. over 90% of reported cases of AIDS occurred among two subgroups, homosexual males and intravenous substance abusers (IVSAs). Currently, there is no anti-cocaine addiction medication available. In order to explore vaccination as an alternative means for protection against cocaine addition, we immunized inbred male Fisher rats with either cocaine emulsification in complete Freund adjuvant (CFA) or with cocaine conjugated with keyhole limpet hemocyanin (KLH), as carrier plus CFA. Animals were initially immunized with 0.1 mg/animal of cocaine or cocaine-KLH. Animals were given a booster with the corresponding agents after 4 weeks. Ten animals/group were used. Controls received normal saline at the time of immunizations. These animals were injected, intraperitoneally, with 25 mg/kg of cocaine, and were examined for the analgesic effect of cocaine by the hot plate method. The average analgesic effect of cocaine was significantly reduced (p greater than 0.03) in animals immunized with cocaine-KLH (13.77 s) as compared to saline controls (21.6 s). Fifty percent of the animals (5/10) in the cocaine-KLH group and 33% of the animals (3/9) in the cocaine immunized group appeared completely resistant to the effect of cocaine on the central nervous system (CNS). We also have determined the levels of cocaine-specific antibodies produced by each animal by an ELISA method. Degree of protection from cocaine seems to correlate well with the amount of anti-cocaine antibodies produced by each animal (-0.61).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

Serological findings in patients with allergic bronchopulmonary aspergillosis during remission.

The concentrations of total IgG, complement C3 and circulating immune complexes (CIC) were studied in 15 patients with allergic bronchopulmonary aspergillosis (ABPA) during remission and compared with those of 10 matched controls. The concentrations of complement and circulating immune complexes were similar to those of the controls but 33% of patients with ABPA in remission still had circulating immune complexes, mainly of IgG. Even so, the concentrations of IgG were significantly higher in patients during remission compared to controls but were lower than those observed during the acute stage of ABPA.

Acute Disease↗

Urticarial vasculitis: a histopathologic and clinical review of 72 cases.

BACKGROUND: Urticarial vasculitis is a subset of vasculitis characterized clinically by urticarial skin lesions and histologically by necrotizing vasculitis. OBJECTIVE: A review of patients with urticarial vasculitis was undertaken to further characterize the clinical and histologic findings and to differentiate this disorder from urticaria and other types of cutaneous vasculitis. METHODS: Seventy-two cases of biopsy-proven urticarial vasculitis were selected for a review of medical records, laboratory data, and histologic findings. Fifty cases of simple urticaria were also reviewed for purposes of comparison. RESULTS: Systemic symptoms in patients with urticarial vasculitis included angioedema in 30 patients (42%), arthralgias in 35 (49%), pulmonary disease in 15 (21%), and abdominal pain in 12 (17%). Twenty-three patients (32%) had hypocomplementemia. Forty-six of 72 patients (64%) had lesions that lasted more than 24 hours, 23 of 72 (32%) had painful or burning lesions, and 25 of 72 (35%) had lesions that resolved with purpura. Sixteen biopsy specimens from the 23 patients with hypocomplementemia showed dermal neutrophilia in addition to the perivascular infiltrate. Of the 23 patients with hypocomplementemia, 20 (87%) had fluorescence of the blood vessels and 16 (70%) had fluorescence of the basement membrane zone as determined by routine direct immunofluorescence. CONCLUSION: Patients with hypocomplementemia were more likely to have systemic symptoms such as urticaria that resolved with purpura, arthralgias, abdominal pain, and chronic obstructive pulmonary disease. The histologic pattern associated with hypocomplementemia is interstitial neutrophilic infiltrate of the dermis and an immunofluorescent pattern of immunoglobulins or C3 in the blood vessels and along the basement membrane zone.

Biopsy↗

Association of a 38 kDa bovine serum protein with the outer membrane of Bordetella pertussis.

Upon cultivation of Bordetella pertussis in bovine serum, a 38 kDa protein was found to be tightly associated with the outer membrane. The intensity of the 40 kDa porin was reduced under these growth conditions. Exposure of Bordetella pertussis, grown in Stainer and Scholte medium, to bovine serum for 1 h did not result in the appearance of the 38 kDa protein. Unlike the 40 kDa porin however, the electrophoretic mobility of this protein was affected neither by temperature of denaturation nor by the presence of 2-mercaptoethanol. Amino acid sequence analysis of the N-terminal of the 38 kDa protein revealed that his protein had 87% homology to both the mouse and human complement C3 precursors.

Amino Acid Sequence↗

Progesterone and dexamethasone inhibition of estrogen-induced synthesis of DNA and complement in rat uterine epithelium: effects of antiprogesterone compounds.

Progesterone (P) blocks estrogen induction of cell proliferation and synthesis of complement C3 in the epithelium of the immature rat uterus. Here it is shown that dexamethasone (Dex) exerts a similar inhibitory effect on these two parameters. Furthermore, analysis of the newly synthesized, secreted proteins produced during a 20 h explant culture period showed that not only does the uterus synthesize complement C3 but it is capable of proteolytically cleaving complement into its biologically active peptides. Since large doses of P are required for its inhibitory effects and since P can interact with the glucocorticoid receptor (GR), the role of the GR in mediating the P effect was questioned. Two antiprogesterone compounds with reportedly differing antiglucocorticoid activity, ZK98.734 and RU486, were tested for their ability to antagonize the inhibitory actions of P and Dex. Attenuation of estrogen-induced epithelial DNA synthesis by either P or Dex was fully overcome by concurrent administration of either ZK98.734 or RU486. On the other hand, while either antagonist was effective against the inhibitory action of P on estrogen-induced complement C3 synthesis, only ZK98.734 was fully effective in blocking inhibition by Dex. Thus, unlike its activity in rat hepatic cells, ZK98.734 is a potent antiglucocorticoid in the immature rat uterus. Because of this antiglucocorticoid activity, differential antagonism of the P response was not possible using these two steroid analogs. Although these observations support the notion of GR mediated inhibition of estrogen action in the uterus, they do not answer the question of whether P might act through a GR mediated pathway.

Animals↗

Antiandrogenic property of RU 486: enhancement of estrogen-induced uterine peroxidase activity in the rat.

The contragestational steroid RU 486 enhanced the increase in peroxidase activity produced by estradiol in estrogen-primed immature rat uteri and, like the antiandrogen flutamide, RU 486 reversed the inhibitory effect of testosterone on this estrogen-induced response. It antagonized the inhibition produced by progesterone but had no effect on peroxidase induction by itself or in unprimed immature animals. RU 486 also enhanced the effect of estradiol on the synthesis of complement component C3 in the rat uterus. The results confirm that RU 486 possesses antiandrogenic as well as antiprogestational properties. They also suggest that, in normal adult animals, the increase in peroxidase activity in the uterus in response to estrogen is not expressed fully but held in check by other endogenous steroids acting through their individual receptors.

Animals↗

Complement C3, eosinophil cationic protein and symptom evaluation in interstitial cystitis.

Interstitial cystitis is a painful, irritative voiding dysfunction of unknown etiology. In this study 19 women undergoing treatment for interstitial cystitis and 6 healthy women of similar age provided 2 urine and serum specimens with at least a 3-month interval between collections. Complement C3 and eosinophil cationic protein were determined by immunoassay methods, and symptom severity was quantitated with a visual analog scale questionnaire. Concentrations of complement C3 and eosinophil cationic protein from either serum or urine were not significantly different between interstitial cystitis patients and controls at either determination, although substantial differences were noted even between individual initial and followup determinations. Normalization of urine osmolality did not alter these results. Symptom severity scores were significantly greater in interstitial cystitis patients compared to controls but failed to correlate with the concentrations of complement C3 or eosinophil cationic protein. Therefore, the hypothesis that complement C3 and eosinophil cationic protein may be etiological factors of interstitial cystitis is not supported.

Adult↗

Structural features of immunologically active polysaccharides from Ganoderma lucidum.

Three polysaccharides, two heteroglycans (PL-1 and PL-4) and one glucan (PL-3), were solubilized from the fruit bodies of Ganoderma lucidum and isolated by anion-exchange and gel-filtration chromatography. Their structural features were elucidated by glycosyl residue and glycosyl linkage composition analyses, partial acid hydrolysis, acetolysis, periodate oxidation, 1D and 2D NMR spectroscopy, and ESI-MS experiments. The data obtained indicated that PL-1 had a backbone consisting of 1,4-linked alpha-D-glucopyranosyl residues and 1,6-linked beta-D-galactopyranosyl residues with branches at O-6 of glucose residues and O-2 of galactose residues, composed of terminal glucose, 1,6-linked glucosyl residues and terminal rhamnose. PL-3 was a highly branched glucan composed of 1,3-linked beta-D-glucopyranosyl residues substituted at O-6 with 1,6-linked glucosyl residues. PL-4 was comprised of 1,3-, 1,4-, 1,6-linked beta-D-glucopyranosyl residues and 1,6-linked beta-D-mannopyranosyl residues. These polysaccharides enhanced the proliferation of T- and B-lymphocytes in vitro to varying contents and PL-1 exhibited an immune-stimulating activity in mice.

Adjuvants, Immunologic↗

Basic proteins bind immunoglobulin G: a mechanism for demyelinating disease?

Heat-aggregated immunoglobulin G ( HAGG ) bound avidly to solid-phase basic proteins, including myelin basic protein. In contrast, monomeric immunoglobulin bound weakly. Bound HAGG could activate complement. Normal human serum strongly inhibited the binding of HAGG , even when decomplemented or greatly diluted. Cerebrospinal fluid was also inhibitory, but the effect was weaker. Apart from inhibition by decomplemented serum, the biochemical characteristics of the interaction were similar to those of other Fc ligands with IgG, particularly C1q. In multiple sclerosis this interaction could occur between IgG and central-nervous-system myelin basic protein, leading to demyelination by activation of immune mechanisms of tissue damage. Bound IgG is present in multiple sclerosis plaques and IgG from multiple sclerosis patients can produce demyelination in experimental models. However, there is little evidence of any specific immunity to central-nervous-system antigens in multiple sclerosis, and this non-specific interaction might be an important link in the pathogenesis of the disorder.

Blood↗

Stagnant versus dynamic conditions: a comparative adsorption study of blood proteins.

Haemodynamic parameters of flowing blood, such as diffusion, convection, flow and shear rates, are important as they determine the interaction of cells with vessel walls and prosthetic implants in the cardiovascular system. Most of the studies under flow conditions have been performed with platelets or other cells, and less attention has been paid to the effects that these parameters may cause on the adsorption of proteins. For this reason we studied how different shear rates affect the adsorption of human albumin, fibrinogen, total serum proteins, and complement factors 1q and 3c from human serum to silicon surfaces. The most relevant results indicate that during non-flow conditions the amount of adsorbed proteins is always lower than under flow. The different shear rates (225, 915, 1800 and 2700 s(-1)) all gave similar results, indicating that such a parameter is not very critical for single protein deposition. The differences in kinetics of complex protein solutions are conveniently highlighted by use of specific polyclonal antibodies. The difference between non-flow or low shear rate conditions and physiological flow conditions was enhanced for the complement cascade system.

Adsorption↗

Isolation of the third component of complement and its derivative with anaphylatoxin-like activity from the plasma of the newt Cynops pyrrhogaster.

The third component of complement (C3) of a newt, Cynops pyrrhogaster, was purified using a fast protein liquid chromatography technique. The purified newt C3 consists of two polypeptide chains (the molecular masses of the alpha and beta-chains of C3 were 120,000 and 70,000, respectively) linked by disulfide bonds. The alpha-chain retained an internal thiolester bond that was cleaved with methylamine, and the N-terminal amino acid sequence of the alpha-chain was XVQLIDAKAGKAAKF. Digestion of newt C3 with trypsin yielded fragments that induced significant histamine release from newt peritoneal cells. These results indicate that newt C3 retains structural and functional properties shared with mammalian C3.

Amino Acid Sequence↗

Opsonic complement system of the solitary ascidian, Halocynthia roretzi.

To elucidate the molecular architecture and function of the possibly primitive complement system of the solitary ascidian. Halochynthia roretzi, cDNA clones for the third component (C3) and mannose-binding lectin (MBL)-associated serine protease (MASP) were isolated from the hepatopancreas cDNA library. The deduced primary structure of ascidian C3 (AsC3) shows overall similarity to mammalian C3 including a typical thioester site. Two distinct ascidian MASPs, termed AsMASPa and AsMASPb, have the same domain structure as mammalian Clr/ Cls/MASP-1/MASP-2. Both of them show a closer similarity to mammalian MASP-1 than to mammalian Clr/Cls/ MASP-2. Ascidian body fluid contains an opsonic activity which enhances phagocytosis of yeast by ascidian blood cells, and an antibody against AsC3 inhibits this opsonic activity. These results indicate that the lectin-dependent, opsonic complement system was present prior to the emergence of the vertebrates and well ahead of the establishment of adaptive immunity.

Animals↗

Intercellular adhesion molecule-1 (ICAM-1, CD 54) is associated with actin-filaments.

Intercellular adhesion molecule 1 (ICAM-1, CD 54) is a membrane associated glycoprotein involved in cell-cell interactions of the immune system. Detergent extraction of cultured human fibroblasts--stimulated with Interferon-gamma (IFN-gamma) for ICAM-1-expression--under conditions that stabilize actin in the filamentous (actin-F) form (NaF-buffer, phalloidine) resulted in greater retention of ICAM-1 in the detergent insoluble phase, containing the cytoskeletal matrix, compared to actin-F-destabilizing conditions (KCl-buffer). We further examined the in vitro ICAM-1 association with actin using immunoaffinity purified ICAM-1, prepared from either normal human tonsils or a spleen derived from a patient with Non-Hodgkin's lymphoma. ICAM-1 from both sources demonstrated binding to actin coated polystyrene surfaces. Our findings suggest that ICAM-1 interacts with actin-F and may use similar mechanisms described with other adhesion molecules for membrane-cytosol communication.

Actins↗

Biodistribution of liposomes and C3 fragments associated with liposomes: evaluation of their relationship.

The biodistribution of liposomes with two different kind phospholipids (hydrogenated egg phosphatidylcholine and egg phosphatidylcholine) plus cholesterol (CHOL) were investigated after intravenous administration to rats. Elimination of liposomes from blood circulation was affected by the lipid composition. It appeared that the inclusion of CHOL in liposomes accelerates the rate of liposome uptake by liver, resulting in rapid elimination of liposomes. The amount of C3 fragments bound to liposomes was quantitatively determined to assess the contribution of the complement system to liposome accumulation into organs and liposome destabilization in vivo and in vitro. The amount of bound C3 fragments was directly proportional to CHOL content, and the amount was also proportional to the CLh, CLs as well as CLrel. This relationship suggests that the complement system is responsible for the elimination of liposomes from blood circulation, presumably as a consequence of opsonization by C3 fragments and assembly of membrane attack complex (MAC) onto liposomes. In addition, substitution of cholesteryl methyl ether into the liposome formulation for CHOL significantly diminished not only the binding of C3 fragments but also the CLh, CLs and CLrel, resulting in increased mean resident time (MRT) of the liposomes. This result suggests that the hydroxyl-group on CHOL is a binding site for C3 fragments on the liposomes and that CHOL in a liposome formulation promotes the accumulation of liposomes into the liver and spleen, probably due to their uptake by phagocytic cells, and impairs the stability of the liposomes in blood circulation, via a mechanism involving the complement system.

Animals↗