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1.
Braz. j. med. biol. res ; 28(1): 120-4, Jan. 1995. graf
Article Dans Anglais | LILACS | ID: lil-153339

Résumé

Pertussis toxin (Ptx) is a hexameric protein with classical AB architecture produced by Bordetella pertussis. The aim of this study was to investigate the effect og Ptx on migration of polymorphonuclear leukocytes to site of inflamation and on cell- dependent edema. Ptx was purified from the supernatant of the culture medium of B. pertussis using hydroxylapatite chromatography and fetuin affinity chromatography. Ptx induced a maximal clusterin of Chinese hamster ovary cells at concentration as low as 0.1 ng/ ml. Intravenous inection of Ptx (400 ng) significantly blocked the neutrophil migration induced by 200 ng of lipopolysaccharide (LPS from E. coli O111:B4; 2.27 ñ 0.13 vs 0.61 ñ 0.16 per 10**6 neutrophils/ml; P < 0.001; N = 5) and by 200 ng of formylmethionyl-leucyl-phenylalanine(fMLP; 2.53 ñ 0.45 vs 0.75 ñ 0.14 per 10**6 neutrophils/ml; P < 0.01; N=6) into the peritoneal cavities of male Wistar rats (eighing 150-180). In addition, Ptx (400ng) pretreatment also blocked the edema induced by intraplantar injection of 100 µg carrageenin ( increase in volume: 0.667 ñ 0.087 vs 0.313 ñ 0.058 ml; P < 0.01; N = 5) but not the edema induced by 100 µg dextran ( increase in volume: 0.537 ñ 0.06 vs 0.385 ñ 0.076 ml; P > 0.05; N = 5). These data demonstrate that Ptx blocked neutrophil migration induced by a direct f MLP stimulus of a site of inflammation. In addition, this toxin blocks the indirect stimulus of LPS on neutrophil migration. Furthermore, Ptx also inhibits the neutrophil-dependent edema induced by carrageenin, but not the edema induced by dextran that is in part dependent on basophil cells. These results warrant further studies on the mechanisms of Ptx inhibition of neutrophil-dependent edema and cell migration


Sujets)
Animaux , Mâle , Rats , Inhibition de la migration cellulaire , Inflammation/physiopathologie , N-Formyl-méthionyl-leucyl-phénylalanine/pharmacologie , Granulocytes neutrophiles/physiologie , Toxine pertussique/pharmacologie , Carragénane/pharmacologie , Dextrane/pharmacologie , Lipopolysaccharides/pharmacologie , Toxine pertussique/isolement et purification
2.
Rev. microbiol ; 25(1): 16-23, jan.-mar. 1994. tab
Article Dans Anglais | LILACS | ID: lil-152560

Résumé

Estudou-se a produçäo de toxina pertussis (PT) e hemaglutininas filamentosas (FHA) para vacinas do vírus Bortella pertussis em cultura supernadante e em supernadante de células lavadas com soluçöes iônicas. O vírus cresceu em meio Stainer-Scholte (SS) e na modificaçäo chamou-se CL-basal (CL-b) e desse meio com heptakis (2,6-0-Dimethyl Beta-Cyclodextrin (MeBCD). FHA e PT foram estimados pelo total de hemaglutinaçäo, hemaglutinaçäo diferencial (com colesterol) e imunoensaio dot-blot. O meio CL-b decresce a produçäo de massa celular e também decresceria a estabilidade e liberaçäo de hemaglutininas. A adiçäo of MeBCD para SS ou meio CL-b estimularia a produçäo, exportaçäo e estabilidade de PT e FHA. Esses efeitos säo maiores para meio CL-b e mais importante para FHA. Esses efeitos säo maiores par meio CL-b e mais importante para FHA que para PT. Obteve-se resultados similares com a adiçäo de 0,5 ou 1g/l de MeBCD para CL-b. Cultura supernadante contém FHA e PT mas supernadantes de células em soluçäo única contém basicamente FHA e seeria usada para prover esse campo


Sujets)
Bordetella pertussis/isolement et purification , Vaccin anticoquelucheux/ressources et distribution , Toxine pertussique/isolement et purification , Hémagglutinines/biosynthèse
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