9 documents found, page 1 of 1
A mouse model reproducing the pathophysiology of neonatal group B streptococcal...
Bonifácio Andrade, Elva; Magalhães, Ana; Puga, Ana; Costa, Madalena; Bravo, Joana; Portugal, Camila Cabral; Ribeiro, Adília; Correia-Neves, MargaridaGroup B streptococcal (GBS) meningitis remains a devastating disease. The absence of an animal model reproducing the natural infectious process has limited our understanding of the disease and, consequently, delayed the development of effective treatments. We describe here a mouse model in which bacteria are transmitted to the offspring from vaginally colonised pregnant females, the natural route of infection. ...
A mouse model reproducing the pathophysiology of neonatal group B streptococcal...
Andrade, Elva Bonifácio; Magalhães, Ana; Puga, Ana; Costa, Madalena; Bravo, Joana; Portugal, Camila Cabral; Ribeiro, Adília; Correia-Neves, MGroup B streptococcal (GBS) meningitis remains a devastating disease. The absence of an animal model reproducing the natural infectious process has limited our understanding of the disease and, consequently, delayed the development of effective treatments. We describe here a mouse model in which bacteria are transmitted to the offspring from vaginally colonised pregnant females, the natural route of infection. ...
TLR2-Induced IL-10 production impairs neutrophil recruitment to infected tissue...
Andrade, Elva Bonifácio; Alves, Joana; Madureira, Pedro; Oliveira, Liliana; Ribeiro, Adília; Silva, Anabela Cordeiro da; Neves, Margarida CorreiaSepsis is the third most common cause of neonatal death, with Group B Streptococcus (GBS) being the leading bacterial agent. The pathogenesis of neonatal septicemia is still unsolved. We described previously that host susceptibility to GBS infection is due to early IL-10 production. In this study, we investigated whether triggering TLR2 to produce IL-10 is a risk factor for neonatal bacterial sepsis. We observe...
Staphylococcus epidermidis biofilms with higher proportions of dormant bacteria...
Cerca, Filipe; Andrade, Filipa; França, Ângela; Bonifácio, Elva; Ribeiro, Adília; Almeida, A. J.; Cerca, Nuno; Pier, Gerald B.; Azeredo, JoanaStaphylococcus epidermidis is an opportunistic pathogen due to its ability to establish biofilms on indwelling medical devices. The presence of high amounts of dormant bacteria is a hallmark of biofilms, making them more tolerant to antimicrobials and to the host immune response. We observed that S. epidermidis biofilms grown in excess glucose accumulated high amounts of viable but non-culturable (VBNC) bacteri...
Inhibition of IL-10 production by maternal antibodies against group b streptoco...
Madureira, Pedro; Andrade, Elva Bonifácio; Gama, Bernardo; Oliveira, Liliana; Moreira, Susana Margarida Gomes; Ribeiro, Adília; Neves, Margarida CorreiaGroup B Streptococcus (GBS) is the leading cause of neonatal pneumonia, septicemia, and meningitis. We have previously shown that in adult mice GBS glycolytic enzyme glyceraldehyde-3-phosphate dehydrogenase (GAPDH) is an extracellular virulence factor that induces production of the immunosuppressive cytokine interleukin-10 (IL-10) by the host early upon bacterial infection. Here, we investigate whether immunity...
Staphylococcus epidermidis biofilms with higher proportions of dormant bacteria...
Cerca, Filipe; Andrade, Filipa; França, António; Bonifácio, Elva; Ribeiro, Adília; Almeida, A. J.; Cerca, Nuno; Pier, Gerald B.; Azeredo, JoanaStaphylococcus epidermidis an opportunistic pathogen due to its ability to establish biofilms on indwelling medical devices. The presence of high amounts of dormant bacteria is a hallmark of biofilms, making them more tolerant to antimicrobials and to the host immune response. We observed that S. epidermidis biofilms grown in excess glucose accumulated high amounts of viable but non-culturable (VBNC) bacteria, ...
Extracellular matrix in Staphylococcus epidermidis biofilms: a consequence of b...
Cerca, Filipe; Andrade, Filipa; Correia, Alexandra; Teixeira, Luzia; Magalhães, Ângela; Hinzmann, Mariana; Ferreira, Íris; Ribeiro, AdíliaStaphylococcus epidermidis is a leading pathogen accounting for nosocomial infections. The ability to form biofilms is considered the major virulence factor of this bacterium. The hallmark of this type of infection is the presence of an extracellular polymeric matrix that, in the case of S. epidermidis biofilms, is mainly constituted by an N-acetylglucosamine polymer. We have identified a subpopulation of bacte...
A study on the immune response elicited in mice challenged with Staphylococcus ...
Cerca, Filipe; Teixeira, Luzia; Cerca, Nuno; Madureira, Pedro; Ribeiro, Adília; Azeredo, Joana; Vilanova, ManuelIn this study a biofilm-forming strain of Staphylococcus epidermidis was used in order to evaluate, in a murine model, the immune response to bacteria grown either as planktonic cells or biofilm. Groups of male BALB/c mice were infected intra-peritoneally (i.p.), with 2×10^8 S. epidermidis cells per mice, obtained either from a mature biofilm (grown for 48h) or from a planktonic cell culture. Mice were sacrific...
Protection against systemic candidiasis in mice immunized with secreted asparti...
Vilanova, Manuel; Teixeira, Luzia; Caramalho, Íris; Torrado, Egídio; Marques, Andreia; Madureira, Pedro; Ribeiro, Adília; Ferreira, Paula; Gama, F. M.Secreted aspartic proteinases (Sap) have been described as virulence factors implicated in the mechanisms of host colonization by the yeast Candida albicans in different types of candidiasis. Intraperitoneal inoculation of C. albicans into BALB/c mice rapidly leads to systemic candidiasis, with significant colonization of the kidneys measurable in the following week. In this study we assessed the potential of v...