Abstract:
:Pseudomonas aeruginosa utilizes a number of distinct pathways to secrete proteins that play various roles during infection. These include the type II secretion system, which is responsible for the secretion of the majority of exoproducts into the surrounding environment, including toxins and degradative enzymes. In contrast, the type III secretion system mediates the delivery of protein effectors directly into the cytoplasm of the host cell. Using tissue culture assays and a mouse acute-pneumonia model, we have determined the contribution of each of the type III effectors during infection. In strain PAK, ExoS is the major cytotoxin required for colonization and dissemination during infection. ExoT confers protection of tissue culture cells from type III-dependent lysis, while ExoY seemed to have little effect on cytotoxicity. ExoU is over 100-fold more cytotoxic than ExoS. The cytotoxicity of type II secretion was determined following deletion of the genes for the more toxic type III secretion system. The participation of these secretion systems during lifelong colonization of cystic fibrosis (CF) patients is unclear. By comparing clonal strains from the same patient isolated at the initial onset of P. aeruginosa infection and more than a decade later, after chronic colonization has been established, we show that initial strains are more cytotoxic than chronic strains that have evolved to reduce type III secretion. Constitutive expression of genes for the type III secretion system restored ExoS secretion but did not always reestablish cytotoxicity, suggesting that CF strains accumulate a number of mutations to reduce bacterial toxicity to the host.
journal_name
Infect Immunjournal_title
Infection and immunityauthors
Lee VT,Smith RS,Tümmler B,Lory Sdoi
10.1128/IAI.73.3.1695-1705.2005keywords:
subject
Has Abstractpub_date
2005-03-01 00:00:00pages
1695-705issue
3eissn
0019-9567issn
1098-5522pii
73/3/1695journal_volume
73pub_type
杂志文章abstract::This study has demonstrated the extreme sensitivity of Chlamydia trachomatis growing in McCoy cells to small changes in external amino acid supply. In the absence of cycloheximide, a decrease in the amino acid concentration of medium to 75% of control values was sufficient to induce the growth of enlarged chlamydial f...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.68.3.1457-1464.2000
更新日期:2000-03-01 00:00:00
abstract::Killing of Salmonella minnesota and Salmonella typhimurium S and R strains in serum of nonimmune humans and guinea pigs was drastically reduced in the selective absence of C1q, C1r, Ca2+, C4, or C2, the components of the classical complement pathway. Binding of C1 and C1q to the S form and six different core-deficient...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.37.3.935-939.1982
更新日期:1982-09-01 00:00:00
abstract::Evidence is presented that the chronicity of infection in CBA mice after injection of Brucella abortus 19 is related to a number of factors: (i) the relative resistance of B. abortus to macrophage killing, which allowed some bacteria to survive the peak of macrophage activity occurring at 14 days; (ii) the decline in ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.23.2.197-205.1979
更新日期:1979-02-01 00:00:00
abstract::Fibrosis is a significant complication of intestinal disorders associated with microbial dysbiosis and pathobiont expansion, notably Crohn's disease (CD). Mechanisms that favor fibrosis are not well understood, and therapeutic strategies are limited. Here we demonstrate that colitis-susceptible Il10-deficient mice dev...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.00587-19
更新日期:2019-10-18 00:00:00
abstract::Antibodies induced in sera and saliva of rats and rabbits immunized with ribosomal preparations from Streptococcus mutans 6715 inhibited transport of glucose by the phosphotransferase system by greater than 60%, acid production from sucrose by greater than 95%, and growth of the homologous S. mutans by greater than 59...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.45.1.286-289.1984
更新日期:1984-07-01 00:00:00
abstract::The ability of human clinical isolates of Yersinia enterocolitica to interact with HEp-2 cells was found to vary considerably between the serotypes O:3, O:8, and O:9. Although all three serotypes adhered initially to the cell surface, regardless of incubation temperature of the bacterial inoculum or presence of the 40...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.52.1.85-89.1986
更新日期:1986-04-01 00:00:00
abstract::The recent development of acellular pertussis vaccines has been a significant improvement in the conventional whole-cell diphtheria-pertussis-tetanus toxoid vaccines, but high production costs will limit its widespread use in developing countries. Since Mycobacterium bovis BCG vaccination against tuberculosis is used ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.68.9.4877-4883.2000
更新日期:2000-09-01 00:00:00
abstract::Murine bone marrow-derived macrophages were infected with a panel of virulent isolates of Mycobacterium tuberculosis including laboratory strains Erdman and H37Rv and various clinical isolates in order to determine the sensitivity of each of these strains to the antimycobacterial activities of macrophage-generated rea...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.65.4.1189-1195.1997
更新日期:1997-04-01 00:00:00
abstract::Mycoplasma salivarium cells propagated in PPLO broth (Difco Laboratories, Detroit, Mich.) supplemented with rabbit serum (10% [vol/vol]) and harvested by centrifugation were shown to contain rabbit immunoglobulin G (IgG) (approximately 4 to 10% of total cell proteins) and to produce IgM autoantibodies to IgG when inoc...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.55.1.263-265.1987
更新日期:1987-01-01 00:00:00
abstract::The importance of intact host defense mechanisms for successful antimicrobial therapy was investigated in an animal model. Recovery from lobar pneumococcal pneumonia as a result of penicillin therapy was studied in normal rats and in rats treated with cobra venom factor. This factor was used to selectively suppress th...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.25.1.366-375.1979
更新日期:1979-07-01 00:00:00
abstract::Histophilus somni is capable of intracellular survival within professional phagocytic cells, but the mechanism of survival is not understood. The Fic motif within the direct repeat (DR1)/DR2 domains of the IbpA fibrillary network protein of H. somni is cytotoxic to epithelial and phagocytic cells, which may interfere ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.00365-18
更新日期:2018-11-20 00:00:00
abstract::Infection with the intracellular protozoan parasite Toxoplasma gondii causes serious public health problems and is of great economic importance worldwide. The micronemal protein MIC3, which is a potent adhesin of T. gondii, could be a significant candidate vaccine against toxoplasmosis. In this study, all CBA/J mice i...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.71.11.6222-6228.2003
更新日期:2003-11-01 00:00:00
abstract::Mice were rendered deficient in B-cell activity by treatment with anti-mu antibody from birth. These animals were then infected intranasally with murine Chlamydia trachomatis (murine pneumonitis agent [MoPn]). They produced neither local nor systemic antibody to MoPn but had intact delayed-type hypersensitivity to MoP...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.55.10.2387-2390.1987
更新日期:1987-10-01 00:00:00
abstract::Uropathogenic Escherichia coli strain J96 carries multiple determinants for fimbrial adhesins. The regulatory protein PapB of P fimbriae has previously been implicated in potential coregulatory events. The focB gene of the F1C fimbria determinant is highly homologous to papB; the translated sequences share 81% identit...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.01010-07
更新日期:2008-02-01 00:00:00
abstract::Lipopolysaccharide (LPS) has recently been shown to facilitate macrophage foam cell formation and has been suggested to be a proatherogenic factor. The mechanism of LPS induced cholesterol accumulation, however, is unclear. In this report, using the macrophage-like RAW 264.7 cell line, we provide experimental evidence...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.70.6.2995-3003.2002
更新日期:2002-06-01 00:00:00
abstract::Staphylococcus aureus nitric oxide synthase (saNOS) is a major contributor to virulence, stress resistance, and physiology, yet the specific mechanism(s) by which saNOS intersects with other known regulatory circuits is largely unknown. The SrrAB two-component system, which modulates gene expression in response to the...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.00570-18
更新日期:2019-01-24 00:00:00
abstract::Chlamydia trachomatis serovar L2 is an obligate intracellular bacterium which is internalized in target epithelial cells by endocytosis and resides within a membrane-bound vesicle. Over the next several hours following entry, individual serovar L2-containing vesicles fuse with one another to form a single membrane-bou...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.64.4.1208-1214.1996
更新日期:1996-04-01 00:00:00
abstract::Urogenital Chlamydia serovars replicating in reproductive epithelium pose a unique challenge to host immunity and vaccine development. Previous studies have shown that CD4 T cells are necessary and sufficient to clear primary Chlamydia muridarum genital tract infections in the mouse model, making a protective CD4 T ce...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.06339-11
更新日期:2012-06-01 00:00:00
abstract::The production of interleukin-6 (IL-6) and its possible relationship to host resistance and inflammatory response to Pneumocystis carinii infection were examined in mice with severe combined immunodeficiency (SCID mice). IL-6 activity was detected in the serum and lungs of P. carinii-infected mice but not in mice free...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.61.1.97-102.1993
更新日期:1993-01-01 00:00:00
abstract::Haemophilus influenzae is a commensal and opportunistic pathogen of the human airways. A number of surface molecules contribute to colonization of the airways by H. influenzae, such as adhesins, including structures found in the lipooligosaccharide (LOS). A human bronchiolar xenograft model was employed to investigate...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.70.8.4661-4668.2002
更新日期:2002-08-01 00:00:00
abstract::Staphylococcus aureus is a prominent human pathogen and a leading cause of community- and hospital-acquired bacterial infections worldwide. Herein, we describe the identification and characterization of the S. aureus 67.6-kDa hypothetical protein, named for the surface factor promoting resistance to oxidative killing ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.00736-10
更新日期:2011-01-01 00:00:00
abstract::Legionella pneumophila is a facultative intracellular bacterium which readily grows in cultures of guinea pig and human mononuclear phagocytes. In this report, we demonstrate that the Legionella sp. also grows in thioglycolate-elicited macrophages obtained from A/J mice but not in cells from other mouse strains tested...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.56.2.370-375.1988
更新日期:1988-02-01 00:00:00
abstract::We report here the identification and characterization of two zinc uptake systems, ZurAM and ZinABC, in the intracellular pathogen Listeria monocytogenes. Transcription of both operons was zinc responsive and regulated by the zinc-sensing repressor Zur. Deletion of either zurAM or zinA had no detectable effect on grow...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.05904-11
更新日期:2012-01-01 00:00:00
abstract::B cell activating factor of the tumor necrosis factor family (BAFF) is an essential survival factor for B cells and has been shown to regulate T cell-independent (TI) IgM production. During Ehrlichia muris infection, TI IgM secretion in the spleen was BAFF dependent, and antibody-mediated BAFF neutralization led to an...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.00998-13
更新日期:2013-12-01 00:00:00
abstract::Gamma interferon (IFN-γ) drives antiparasite responses and immunopathology during infection with Plasmodium species. Immunity-related GTPases (IRGs) are a class of IFN-γ-dependent proteins that are essential for cell autonomous immunity to numerous intracellular pathogens. However, it is currently unknown whether IRGs...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.02701-14
更新日期:2015-04-01 00:00:00
abstract::This study determined the role of crl in the production of curli by, the hemagglutination activity of, and fibronectin binding by avian pathogenic Escherichia coli chi 7122. Curli, an extracellular structure that binds fibronectin, was recently described (A. Olsén, A. Jonsson, and S. Normark, Nature [London] 338:652-6...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.60.11.4460-4467.1992
更新日期:1992-11-01 00:00:00
abstract::Ehrlichia chaffeensis, a tick-transmitted obligate intracellular rickettsial agent, causes human monocytic ehrlichiosis. In recent reports, we described substantial advances in developing random and targeted gene disruption methods to investigate the functions of E. chaffeensis genes. We reported earlier that the Hima...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.00316-20
更新日期:2020-09-18 00:00:00
abstract::Streptococcus agalactiae (group B Streptococcus or GBS) is a common colonizer of the gastrointestinal and genital tracts and an important cause of invasive infections in newborn infants and in adults with predisposing chronic conditions or advanced age. Attachment to epithelial surfaces at mucosal sites is a critical ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.00699-12
更新日期:2012-11-01 00:00:00
abstract::Pathogenic Leptospira spp. are likely to encounter higher concentrations of reactive oxygen species induced by the host innate immune response. In this study, we characterized Leptospira interrogans catalase (KatE), the only annotated catalase found within pathogenic Leptospira species, by assessing its role in resist...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.00466-12
更新日期:2012-11-01 00:00:00
abstract::After transmission by Anopheles mosquitoes, Plasmodium sporozoites travel to the liver, infect hepatocytes, and rapidly develop as intrahepatocytic liver stages (LS). Rodent models of malaria exhibit large differences in the magnitude of liver infection, both between parasite species and between strains of mice. This ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.02230-14
更新日期:2015-01-01 00:00:00