Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0043167 (pertussis)
 19,595 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Secretion of pulmonary surfactant by type II pulmonary epithelial cells (T2P) is regulated by receptor-mediated mechanisms. In other systems, coupling of receptor-linked signals to intracellular events involves guanine nucleotide-binding proteins (G proteins), but the specific role of G proteins in T2P signaling pathways is poorly defined. The present studies begin to address the role of G proteins in transmembrane signaling in these pneumocytes. Membrane preparations from purified T2Ps demonstrated ADP ribosylation of specific substrates by pertussis, cholera, and botulinum toxins (PT, CT, and BT, respectively). Toxin-dependent T2P substrate labeling from 32P-labeled NAD was dependent on time and membrane protein concentration. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis and autoradiography showed ADP ribosylation of membrane substrates of the following molecular masses: PT, 40/41 kDa; CT, 47/51 kDa; BT, 22 kDa. BT-dependent ADP ribosylation of a 22-kDa cytosolic substrate was also observed. Pretreatment of cultured T2P with the individual toxins led to ADP ribosylation of their respective specific substrates in a time-dependent fashion. In cells pretreated with PT or CT, substrates for the complimentary toxins remained available for subsequent ADP ribosylation in vitro. This result supports the specificity of the toxin effects. Basal secretion of the major phospholipid of pulmonary surfactant, disaturated phosphatidylcholine (DSPC) was unaffected in T2P treated with PT, but was stimulated in cells exposed to CT or BT. Neither CT nor BT altered release of lactate dehydrogenase. In cells treated with AMP or with isoproterenol DSPC secretion was stimulated six- to eightfold; preexposure of the cells to CT reduced the response to either agonist by 70%.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:ADP ribosylation of type II pulmonary epithelial cell G proteins. 164 81

The effect of atrial natriuretic factor (ANF) on adenylate cyclase activity was studied in rat platelet membranes. ANF-(99-126)-, -(101-126)-, -(103-126)- and -(103-123)-peptide inhibited adenylate cyclase activity in a concentration-dependent manner with an order of potency of ANF-(103-123)-peptide greater than ANF-(99-126)-peptide greater than ANF-(101-126)-peptide greater than ANF-(103-126)-peptide. ANF-(103-123)-peptide and ANF-(99-126)-peptide inhibited the enzyme activity by about 50-55%, with an apparent Ki between 0.1 and 0.5 nM, and ANF-(101-126)-peptide inhibited the enzyme activity by about 35%, with an apparent Ki between 1 and 3 nM. On the other hand, ANF-(103-126)-peptide was the least potent and inhibited the adenylate cyclase activity by about 30% (Ki approximately 10 nM). The inhibitory effect of ANF on adenylate cyclase was also dependent on the presence of guanine nucleotides and was attenuated by amiloride and pertussis toxin. The stimulatory effects of various agonists such as N-ethylcarboxamideadenosine, prostaglandin E1, isoprenaline and forskolin on adenylate cyclase were also inhibited by ANF to various extents; however, the stimulations were not completely abolished. In addition, 125I-labelled ANF-(99-126)-peptide bound specifically to rat platelet membranes. The binding of 125I-ANF was competitively inhibited in a concentration-dependent manner by the unlabelled peptides which were used for adenylate cyclase inhibition. ANF-(103-123)-peptide, ANF-(99-126)-peptide and ANF-(101-126)-peptide were almost equipotent [IC50 (median inhibitory concentration) = 0.1-1 nM], and ANF-(103-126)-peptide was the least potent (IC50 approximately 10 nM). Scatchard analysis of the data revealed the presence of a single class of binding sites of high affinity (Kd approximately 120 pM). Affinity cross-linking of 125I-ANF-(99-126)-peptide to its binding sites in rat platelet membranes and analysis by SDS/PAGE followed by autoradiography showed a predominant labelling of a protein band with an apparent Mr of 66,000. These data indicate the presence of only ANF-R2 (low-Mr) receptors in platelets and suggest that these receptors may be coupled to the adenylate cyclase system.
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PMID:The presence of atrial-natriuretic-factor receptors of ANF-R2 subtype in rat platelets. Coupling to adenylate cyclase/cyclic AMP signal-transduction system. 165 38

Pertussis toxin (PT), an oligomeric exotoxin of Bordetella pertussis containing five dissimilar subunits, is considered to be an essential immunogen in acellular and component pertussis vaccines against whooping cough. A rapid single-step procedure for isolating PT subunits was developed using reverse-phase high-performance liquid chromatography. Recoveries of individual subunits were 75% (S1), 70% (S2), greater than 90% (S3), greater than 90% (S4), and 50% (S5), as judged by SDS-PAGE and amino acid analysis. Lyophilized subunits were solubilized in urea followed by step-wise dialysis to remove the urea. All subunits were inactive in histamine sensitization, lymphocytosis, and hemagglutination assays. However, purified S1 retained residual NAD-glycohydrolase and ADP-ribosyltransferase activity. A partially active holotoxin could be generated by mixing the five individual subunits. All subunits were immunogenic in rabbits and mice. Monospecific antisera raised in both animal species were able to neutralize the PT-mediated clustering of Chinese hamster ovary cells, but active immunization of mice with single subunits failed to protect them in the intracerebral challenge assay. These subunit preparations therefore retained neutralizing determinants, but did not contain protective epitopes.
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PMID:Purification and immunological characterization of HPLC-purified pertussis toxin subunits. 165 40

We obtained highly purified fimbrae from Bordetella pertussis cells which gave a single band in SDS-polyacrylamide gel electrophoresis. Using the purified fimbriae, we prepared anti-fimbriae rabbit or goat IgGs by fimbriae-Sepharose affinity chromatography, and developed ELISA for its determination. The concentration of fimbriae in our former type of acellular vaccine (80 micrograms per ml) was determined to be 20 ng per ml, and that in our component vaccine was at an almost negligible level. To estimate the protective effects of the small levels of fimbriae, we evaluated the protective activities of three types of vaccines; the former type acellular vaccine (pertussis toxin (PT): filamentous hemagglutinin (FHA): fimbriae = 15:61:0.02 (microgram per ml)), the two-component vaccine (16:64:0.0001), and the three-component vaccine (16:63:0.8). The three types of vaccines showed no significant differences in protectivity against the experimental aerosol infection suggesting that these levels of fimbriae are not effective against the experimental aerosol infection of mice with Bordetella pertussis.
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PMID:Comparison of the protective effects of the pertussis acellular vaccine with the component vaccine, which have different amounts of fimbriae, against the experimental aerosol infection of mice with Bordetella pertussis. 168 13

The peptide hormones bradykinin and kallidin (Lys-bradykinin), as well as their analogues [des-Arg9]-bradykinin, a selective B1 agonist, [des-Arg9,Leu8]-bradykinin, a selective B1 antagonist, and [Thi5,8,D-Phe7]-bradykinin and D-Arg0-[Hyp3,D-Phe7]-bradykinin, two selective B2 antagonists, induced rapid histamine release from purified rat peritoneal mast cells. In contrast, the N-terminal fragment bradykinin-(1-5) was inactive. These peptides also activate the GTPase activity of GTP-binding proteins (G proteins) (Go/Gi) purified from calf brain, with an order of potency identical to that observed on mast cells, [Thi5,8,D-Phe7]-bradykinin much greater than kallidin greater than bradykinin greater than D-Arg0-[Hyp3,D-Phe7]-bradykinin greater than [des-Arg9]-bradykinin greater than [des-Arg9,Leu8]-bradykinin greater than bradykinin-(1-5). This correlation suggested that G proteins are the targets of kinins in mast cells. Accordingly, the concomitant increase in inositol trisphosphates and release of histamine elicited by kinins were inhibited by pertussis toxin pretreatment of mast cells. The inhibitory effect of benzalkonium chloride showed that the G proteins involved belong to the Gi type. GTPase activity was measured in the supernatant of homogenized mast cells but not in the membranous fraction. This activity was stimulated by kinins and by the venom peptide mastoparan. The potency of peptides was similar to that observed with purified bovine G proteins. Sodium dodecyl sulfate-gel electrophoresis of mast cell supernatant revealed pertussis toxin-induced ADP-ribosylation of two proteins, in the Mr 41,000 and 40,000 range, i.e., similar to purified alpha-subunits of Gi1 and Gi2 or Gi3 subtypes. The data support the proposal that bradykinin and analogues act like mastoparan, substance P, and compound 48/80, interacting first with sialic acid residues of the cell surface and then with Gi-like proteins, inducing phospholipase C activation and intracellular calcium mobilization.
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PMID:Activation of Gi-like proteins, a receptor-independent effect of kinins in mast cells. 170 Dec 14

Spleen cells from mice immunized with a Bordetella pertussis N-lauroyl sarcosine membrane extract (SME) were used to generate hybridoma cells lines producing monoclonal antibodies (mAbs). Seven mAbs were shown to be specific to B. pertussis lipo-oligosaccharide (LOS) by immunoblotting of SME or purified LOS following SDS-PAGE. All mAbs reacted with the B. pertussis Tohama I strain of the LOS AB phenotype, and did not react with the atypical variant strain 134 of the LOS B phenotype. The immune reactivity of the mAbs was retained after treatment of SME with proteinase K and was lost after sodium periodate treatment. No cross-reactivity was observed with the mAbs when tested against B. parapertussis and other Gram-negative bacteria. However, all mAbs reacted with B. bronchiseptica. Binding assays with live B. pertussis cells demonstrated that mAbs strongly reacted with cell surface exposed antigenic determinants. High bacterial cell lytic capability was observed for five of these mAbs. Concentrations between 0.22 and 2.2 micrograms mAb ml-1 (0.1 and 1 microgram per 450 microliter assay) purified by protein A were required to kill at least 50% of the bacteria. Competition immunoassays with biotinylated antibodies showed that the bacteriolytic and non-bacteriolytic mAbs were directed to different epitopes of the B. pertussis LOS A.
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PMID:Characterization and comparative bactericidal activity of monoclonal antibodies to Bordetella pertussis lipo-oligosaccharide A. 171 58

The heterohybridoma cell line HBp2 secreting human monoclonal antibody (hMAb) directed against Bordetella pertussis was generated by fusing SP2/HPT heteromyeloma cells with human spleen lymphocytes, after in vitro stimulation for 6 days. The hybridoma was maintained in culture for more than 1 year with continuous antibody secretion. The hMAb HBp2, an IgM, reacted with untreated and proteinase K-treated B. pertussis outer membrane antigens, whereas the reactivity was lost when the antigen was treated with sodium periodate. Human MAb HBp2 was shown to be specific to B. pertussis LOS by immunoblotting of whole cell extracts after SDS-PAGE. In a dot enzyme immunoassay, HBp2 reacted with all B. pertussis strains and clinical isolates tested except for four atypical variant strains of the LOS B phenotype. Human MAb HBp2 also reacted with a clinical isolate of B. bronchiseptica. No reaction was observed against B. parapertussis and other gram-negative species. Together these studies suggested that HBp2 is reactive with carbohydrate epitopes present on the LOS A. Binding assays with live bacteria demonstrated that hMAb HBp2 reacted with cell surface exposed epitopes on B. pertussis but the antibody did not bind significantly to the surface on intact B. bronchiseptica cells. When examined for bactericidal activity in the presence of complement, hMAb HBp2 showed high lytic capability against B. pertussis while no killing was obtained against B. bronchiseptica. These experiments established that LOS A is a target for human bactericidal antibodies. This antigen merits further investigation as a potentially important component in human immunity to B. pertussis infection.
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PMID:Biological activity of a human monoclonal antibody to Bordetella pertussis lipooligosaccharide. 172 52

3H-Labelled kappa-elastin peptides (kE:75 kDa molecular weight) were shown to bind to confluent human skin fibroblast (HSF) cultures in a time-dependent and saturable manner. Scatchard analysis indicated the presence of high affinity binding sites with kD = 2.7 x 10(-10) M and 19,000 sites per cell. Binding of kE to its receptor on HSF accelerates and intensifies the adhesion of insoluble elastin fibres (iE) to confluent HSF. Optimal effect was attained for a kE concentration of 0.3 x 10(-9) M close to kD. This stimulatory effect of kE on the binding of iE to HSF could be inhibited by neomycin, retinal and pertussis toxin, substances which act at different levels of the transduction mechanism following the activation of the receptor and the subsequent triggering of cell biological events (chemotaxis, modification of calcium fluxes). The stimulation of iE adhesion to HSF induced by kE as well as kE binding to the cells could be inhibited by lactose and laminin but not by Arg-Gly-Asp-Ser(RGDS) peptides. This indicates that the elastin peptide receptor on HSF possesses lectin-like properties and shares homology with the laminin receptor as also shown for other cell types. None of the substances tested, that is inhibitors of the transduction mechanism, lactose, laminin and Arg-Gly-Asp-Ser(RGDS) peptides were shown to interfere significantly with the binding of iE (in the absence of added kE) to confluent HSF. The proteins adhering strongly to elastin fibres were isolated by a sequential extraction procedure and the final hydrochloride guanidinium-DTT extract was analysed by SDS-PAGE under reducing conditions, Western blots using specific antibodies against several connective tissue proteins and affinity for [3H]-kE following nitrocellulose electro-transfer of proteins. Fibronectin, vitronectin, tropoelastin(s), and a 120 kDa cysteine rich glycoprotein previously designated as elastonectin were identified. Among these proteins, [3H]-kE was found to bind exclusively to a 65 kDa protein that could be eluted selectively from elastin fibres with a neutral buffer containing 100 mM lactose. Therefore the elastin peptide receptor on human skin fibroblasts shares properties with the elastin receptor characterized from other cell types. Conformational differences between elastin peptides and elastin fibres could explain the differences in the mechanisms of interactions between elastin fibres and elastin peptides with HSF in culture. The stimulatory effect of elastin-derived peptides on the adhesion of elastin fibres to HSF could have implications in the oriented biosynthesis of elastin fibres.
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PMID:Mechanisms of interaction between human skin fibroblasts and elastin: differences between elastin fibres and derived peptides. 172 59

Platelet G proteins were assessed in 7 normal volunteers before and after 14 days of lithium administration at therapeutic plasma levels. Cholera and pertussis toxin catalyzed ADP-ribosylation of platelet membrane proteins were measured by SDS-PAGE. Immunoblotting with specific antibodies was used to measure platelet membrane alpha i content. There was a statistically significant 37% increase in pertussis toxin mediated ADP-ribosylation of a 40,000 Mr protein in platelet membranes after lithium administration, but cholera toxin mediated ADP-ribosylation of a 45,000 Mr protein and alpha i immunoblotting were unchanged by lithium. Increased pertussis toxin stimulated ADP-ribosylation in the absence of changes in alpha i content could be explained by a shift in platelet Gi in favor of its undissociated, inactive form. This would be consistent with increased platelet adenylyl cyclase activity found in these same subjects after lithium.
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PMID:Lithium administration modulates platelet Gi in humans. 173 Nov 75

Lipopolysaccharides (LPS) isolated from Bordetella pertussis (Bp), B. parapertussis (Bpp), and B. bronchiseptica (Bbs) were analysed for their chemical composition, molecular heterogeneity, and immunological and biological properties. All LPS contained heptose, KDO, GlcN, uronic acid, phosphate, and fatty acids. The fatty acids C14:0, C16:0 and 3-OHC14:0 were common to all LPS preparations. By SDS-PAGE, Bp-LPS had two bands of low molecular mass, and Bpp- and Bbs-LPS showed a low molecular mass band together with ladder bands of high molecular mass. Immunological assays demonstrated that Bp-LPS reacted with antisera prepared from Bp and Bpp; Bpp-LPS reacted with antisera against Bpp and Bbs, and Bbs-LPS reacted with antisera against any of the three species. Bp-LPS showed biological activities comparable to those of E. coli LPS in terms of lethal toxicity, pyrogenicity, mitogenicity, macrophage activation, and induction of tumor necrosis factor. All activities of Bpp-LPS, except mitogenicity, were lower than those of E. coli LPS. Biological activities stronger or comparable to those of E. coli LPS were observed for Bbs-LPS.
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PMID:Structural and biological comparison of lipopolysaccharides (LPS) from Bordetella species. 177 13


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