ABSTRACT
The proteolytic activity (PA) of some microorganisms is an important pathogenic factor during tissue invasion. However, its role in Helicobacter pylori infection is not clear. Due to the importance of the immunological response to inhibit pathogenic factors of microorganisms, this study aims to establish an in vitro system to detect inhibitory antibodies to the PA of H. pylori in mouse serum. We obtained mouse sera from animals immunized by oral and intraperitoneal inoculations with the raw bacterial extract (BE) of H. pylori, in which we had previously detected PA. The degradation of azocasein subtract for BE was inhibited in 49.23 and 22.6 using 5 micrograms/ml of serum proteins (SP) from oral and intraperitoneal inoculation, respectively. However, when using more than 25 micrograms/ml of SP of immune serum, PA was inhibited in a similar way than with control serum. In conclusion we present a methodology for the detection of inhibitory antibodies to PA of H. pylori in the serum of the immunized mouse.
Subject(s)
Animals , Female , Mice , Antibodies, Bacterial/pharmacology , Endopeptidases , Gastritis, Atrophic/microbiology , Helicobacter pylori , In Vitro Techniques , Helicobacter Infections/microbiology , Bacterial Proteins/antagonists & inhibitors , Administration, Oral , Antibodies, Bacterial/immunology , Antigens, Bacterial/administration & dosage , Antigens, Bacterial/immunology , Enzyme-Linked Immunosorbent Assay , Helicobacter pylori , Immune Sera , Immunization , Mice, Inbred BALB C , Specific Pathogen-Free OrganismsABSTRACT
O isolamento de cepas de Staphylococcus aureus resistente à vancomicina (VRSA) de amostras clínicas foi rekatado no Japão, França, Estados Unidos e Coréia, mas ainda não havia sido relatado no Brasil. O objetivo deste estudo foi avaliar a possível presença de cepas hetero-VRSA ou VRSA em 05 hospitais públicos da cidade de São Paulo. No total, foram triadas 469 cepas de S aureus resistentes à oxacilina (ORSA), das quais 198 foram isoladas no Hospital Geral de Vila Penteado (HGVP), 137 no Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo (HCFMUSP), 50 no Hospital AC Camargo, 48 no Hospital Emílio Ribas e 36 no Hospital Universitário da USP. A triagem das cepas hetero-VRSA e VRSA foi realizada...
Subject(s)
Humans , Anti-Bacterial Agents , Antibodies, Bacterial/pharmacology , Antibodies, Bacterial/immunology , DNA, Bacterial , Glycopeptides , In Vitro Techniques , Cross Infection/epidemiology , Cross Infection/immunology , Cross Infection/microbiology , Microbiology , Vancomycin Resistance/immunology , Staphylococcus aureus , Bacterial Growth , Cell Culture Techniques , Electrophoresis, Gel, Pulsed-Field , Polymerase Chain Reaction , Cell Separation/methods , Specimen HandlingABSTRACT
Se evaluó la cinética de la respuesta de anticuerpos bactericidas frente a la cepa vacunal Cu85/83 (B:4P1.15) y de la IgG específica contra proteínas vacunales (PV) en 220 individuos vacunados con VA-MENGOC-BC, vacuna cubana contra la Neisseria meningitidis serogrupo B y C. Se realizó un análisis multivariado y los mayores incrementos de IgG anti-PV y de la actividad bactericida sérica (ABs) se observaron después de la segunda dosis vacunal, lo que sugiere la existencia de memoria inmunológica dependiente de células B como mecanismo protector
Subject(s)
Humans , Male , Adult , Multivariate Analysis , Antibodies, Bacterial/pharmacology , Bacterial Vaccines/pharmacokinetics , Enzyme-Linked Immunosorbent Assay , Neisseria meningitidis/immunologyABSTRACT
We have investigated different experimental schedules to achieve adherence of Neisseria meningitidis group B to cultured and buccal epithelial cells (BEC) and the effect of antibodies and receptor analogues on bacterial adherence. No adherence of meningococcus was observed when HeLa, HEp-2 or KB cells were used, but high rates of adherence to BEC occurred. The effect of antibodies on bacterial adherence was studied in assays carried out in the presence of saliva and serum collected from convalescing children with meningococcal meningitis and children vaccinated with VAMENGOC B-C. Both saliva and serum from the convalescent patients inhibited the adherence of meningococci, but saliva and serum from vaccinated children did not, corroborating our previous data of a poor antibody response induced by this vaccine. Human colostrum did not affect meningococcal adherence despite the presence of antibodies to N. meningitidis detected by ELISA. Inhibition of adherence by sera from an immunized horse, rabbits and mice, as well as by cell receptor analogues (outer-membrane complex and purified polysaccharide C), was observed. Our results show that up to now BEC continue to be the best cells to study meningococcal adherence and the effect of adherence inhibitors.