Abstract:
:Controversy persists over the role that the capsular polysaccharide plays in the pathogenesis of Staphylococcus aureus infections. To address this issue, we compared the mouse virulence of S. aureus Reynolds and capsule-defective mutant strains cultivated under conditions of high or low capsule expression. Strain Reynolds cells cultivated on Columbia salt agar plates expressed approximately 100-fold more type 5 capsular polysaccharide than did cells cultivated in Columbia salt broth. The relative virulence of strain Reynolds and its capsule-defective mutants after growth on either solid or liquid medium was examined in mice challenged intraperitoneally or intravenously. The results indicated that agar-grown Reynolds cells were cleared from the bloodstream of mice less readily than broth-grown Reynolds cells. When the parental and mutant strains were cultivated on solid medium, strain Reynolds sustained a higher level of bacteremia than did the capsular mutants. We performed in vitro opsonophagocytic killing assays to determine whether staphylococcal virulence for mice correlated with resistance to phagocytosis. S. aureus Reynolds cultivated on solid medium was susceptible to phagocytic killing only in the presence of specific capsular antibodies and complement. Strain Reynolds grown in broth showed opsonic requirements for phagocytic killing that were similar to those of the capsular mutants (grown in broth or on agar); i.e., the bacteria were opsonized for phagocytosis by nonimmune serum with complement activity. These studies indicate that optimal expression of capsule enhances bacterial virulence in the mouse model of bacteremia, probably by rendering the organisms resistant to opsonophagocytic killing by leukocytes.
journal_name
Infect Immunjournal_title
Infection and immunityauthors
Thakker M,Park JS,Carey V,Lee JCdoi
10.1128/IAI.66.11.5183-5189.1998subject
Has Abstractpub_date
1998-11-01 00:00:00pages
5183-9issue
11eissn
0019-9567issn
1098-5522journal_volume
66pub_type
杂志文章abstract::An antigenically distinct serotype, type IV, has recently been added to the recognized serotypes of group B streptococci (GBS). We isolated and purified the capsular polysaccharide antigen from a prototype type IV GBS strain. The type IV capsular polysaccharide formed a precipitin line with rabbit antiserum to type IV...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.57.4.1089-1094.1989
更新日期:1989-04-01 00:00:00
abstract::It was shown in this work that the infectivity of metacyclic forms of Trypanosoma cruzi was affected upon interaction with the monoclonal antibody (10D8), which reacts with a carbohydrate epitope of the 35- and 50-kilodalton (kDa) surface glycoconjugates. The invasion of Vero cells by metacyclic forms of strains Tulah...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.57.6.1663-1667.1989
更新日期:1989-06-01 00:00:00
abstract::Enterohemorrhagic Escherichia coli (EHEC) is a prominent, food-borne cause of diarrhea, bloody diarrhea, and the hemolytic uremic syndrome in industrialized countries. Most strains of EHEC carry the locus for enterocyte effacement (LEE) pathogenicity island, but a proportion of isolates from patients with severe disea...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.71.11.6307-6319.2003
更新日期:2003-11-01 00:00:00
abstract::Two phospholipase C fractions were detected in culture supernatants from Pseudomonas aeruginosa ATCC 19660, PAO1, and D10C by preparative polyacrylamide gel electrophoresis. Both hemolytic fractions from strain ATCC 19660 were isolated by polyacrylamide gel electrophoresis and were found to cause paralysis, death, der...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.55.7.1728-1730.1987
更新日期:1987-07-01 00:00:00
abstract::Complement receptor type 3 (CR3) was initially described as an opsonic receptor. Subsequently, CR3-mediated lectin-sugar recognition mechanisms have been shown to play a major role in the nonopsonic phagocytosis of several pathogens, among them Mycobacterium tuberculosis. Little is known about the binding and signal t...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.68.8.4736-4745.2000
更新日期:2000-08-01 00:00:00
abstract::The mechanisms of immunity to salmonellae conferred by immunization with live vaccines were studied by adoptive transfer using the mouse-virulent strain Salmonella typhimurium C5 and innately susceptible BALB/c (ltys) mice. This organism cannot establish a sublethal infection in naive BALB/c mice. Animals immunized 2 ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.61.9.3981-3984.1993
更新日期:1993-09-01 00:00:00
abstract::Virulent Treponema pallidum organisms, extracted from infected rabbit testes, were subjected to velocity sedimentation in discontinuous gradients of Hypaque, a high density, low viscosity material. After centrifugation of extracts at 20 C for 45 min at 100,000 x g, treponemes separated into two distinct bands based up...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.10.5.1062-1067.1974
更新日期:1974-11-01 00:00:00
abstract::Recent evidence suggests that immune-mediated gastric epithelial cell apoptosis through Fas-Fas ligand interactions participates in Helicobacter pylori disease pathogenesis. To define the role of Fas signaling in vivo, H. pylori strain SS1 infection in C57BL/6 mice was compared to that in mice deficient in the Fas lig...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.70.5.2591-2597.2002
更新日期:2002-05-01 00:00:00
abstract::The adhesion of K21a, K26, K36, and K50 capsulated Klebsiella strains to ileocecal (HCT-8) and bladder (T24) epithelial cell lines was significantly lower than that of their corresponding spontaneous noncapsulated variants K21a/3, K26/1, K36/3, and K50/3, respectively. Internalization of the bacteria by both epithelia...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.68.12.6744-6749.2000
更新日期:2000-12-01 00:00:00
abstract::Aerobic microorganisms were isolated and identified from 9 of 10 malignant tissues aseptically obtained from surgical patients. The organisms isolated are species commonly associated with the flora of the human body. When these cancer-associated organisms were grown in Trypticase soy broth (BBL Microbiology Systems), ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.32.3.1211-1215.1981
更新日期:1981-06-01 00:00:00
abstract::Stimulated polymorphonuclear leukocytes have been shown by this laboratory to release a reactive-oxygen species (ROS) which is detectable in the supernatant and is capable of oxidizing reduced glutathione and reacting with methionine (Sagone et al., Blood 63:96-104, 1984). This ROS is dependent on H2O2 and heme for it...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.43.3.846-849.1984
更新日期:1984-03-01 00:00:00
abstract::Monoclonal antibody MASC1-MR9 of isotype immunoglobulin M was generated in LOU/C rats by immunization with heat-killed Salmonella thompson (serogroup C1, O-antigen 6,7 lipopolysaccharide) bacteria which had been further enriched for O-antigen by coating with homologous lipopolysaccharide. Eight monoclonal antibodies w...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.59.1.229-233.1991
更新日期:1991-01-01 00:00:00
abstract::In Vibrio cholerae, the transmembrane DNA binding proteins, ToxR and TcpP, activate expression of the regulatory gene toxT in response to specific environmental signals. The resulting enhanced level of ToxT leads to a coordinated increase in the production of a subset of virulence factors, including cholera toxin (CT)...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.72.7.3961-3967.2004
更新日期:2004-07-01 00:00:00
abstract::We developed a human inhibition monoclonal enzyme-linked immunosorbent assay (HIMELISA) to investigate the human immune response to the lipooligosaccharides (LOS) of Neisseria meningitidis. Monoclonal antibodies (MAb) were used to define seven epitopes on four LOS molecules of a meningococcal strain (126E) previously ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.58.7.2204-2213.1990
更新日期:1990-07-01 00:00:00
abstract::We have determined the amounts of specific anti-class 1 outer membrane protein antibodies in sera from 25 patients during the course of systemic meningococcal disease, using purified class 1 protein as the sensitizing antigen in an enzyme-linked immunosorbent assay. The class 1 protein was obtained from a variant of s...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.62.4.1437-1443.1994
更新日期:1994-04-01 00:00:00
abstract::Recent studies have shown that children with blood group A have increased susceptibility to enterotoxigenic Escherichia coli (ETEC) diarrhea and that Lewis blood group "a" antigen (Le(a)) may be a candidate receptor for ETEC colonization factor (CF) antigen I (CFA/I) fimbriae. Based on these findings, we have attempte...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.01571-08
更新日期:2009-05-01 00:00:00
abstract::Group B streptococci (GBS) are the major cause of neonatal pneumonia, sepsis, and meningitis. Steps considered to be important in the pathogenesis of this infection include colonization of the rectum and vagina of the mother, aspiration of GBS into the fetal lung during or just prior to delivery, and invasion of GBS i...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.62.6.2450-2458.1994
更新日期:1994-06-01 00:00:00
abstract::A progressive increase in infections with multiresistant Enterococcus faecium has been reported, especially in cancer patients and neutropenic patients. Despite its increasing importance as a nosocomial pathogen, knowledge of the pathogenesis of E. faecium infections is highly limited. In this study, we investigated t...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.00863-08
更新日期:2009-01-01 00:00:00
abstract::The mechanisms for acquisition of iron by Haemophilus influenzae and their role in pathogenesis are not known. Heme and nonheme sources of iron were evaluated for their effect on growth of type b and nontypable strains of H. influenzae in an iron-restricted, defined medium. All 13 strains acquired iron from heme, hemo...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.56.4.721-725.1988
更新日期:1988-04-01 00:00:00
abstract::Ingestion of 14C-amino acid-labeled Chlamydia psittaci (6BC) by mouse fibroblasts (L cells) was inhibited when the host cells were incubated for 30 min at 37 degrees C in Earle salts containing 10 mug of crystalline trypsin per ml. Tryptic digestion also inhibited the ingestion of 1-mum polystrene latex beads. Trypsin...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.14.3.645-651.1976
更新日期:1976-09-01 00:00:00
abstract::Inbred mouse strains differ in their susceptibility to infection with the facultative intracellular bacterium Listeria monocytogenes, largely due to delayed or deficient innate immune responses. Previous antibody depletion studies suggested that neutrophils (polymorphonuclear leukocytes [PMN]) were particularly import...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.00085-18
更新日期:2018-03-22 00:00:00
abstract::The major merozoite surface protein of Plasmodium falciparum (PfMSP1) is a candidate antigen for a malaria vaccine. A 19-kDa C-terminal processing product of PfMSP1 (PfMSP1(19)) is composed of two domains sharing a cysteine-rich motif with epidermal growth factor (EGF) and is the target of monoclonal antibodies which ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.63.2.456-466.1995
更新日期:1995-02-01 00:00:00
abstract::Lipopolysaccharide (LPS) is cleared from the blood mainly by the liver. The Kupffer cells are primarily responsible for this clearance; liver endothelial and parenchymal cells contribute to a lesser extent. Although several binding sites have been described, only CD14 is known to be involved in LPS signalling. Among t...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.66.11.5107-5112.1998
更新日期:1998-11-01 00:00:00
abstract::Anopheles gambiae is the major African vector of Plasmodium falciparum, the most deadly species of human malaria parasite and the most prevalent in Africa. Several strategies are being developed to limit the global impact of malaria via reducing transmission rates, among which are transmission-blocking vaccines (TBVs)...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.00864-06
更新日期:2007-04-01 00:00:00
abstract::Outer membrane protein F (porin) was purified by extraction from polyacrylamide gels of cell envelope proteins of the Pseudomonas aeruginosa PAO1 strain. Rats were immunized intramuscularly with 25 micrograms of protein F on days 1 and 14 and then challenged on day 28 via intratracheal inoculation of bacterium-contain...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.56.5.1017-1022.1988
更新日期:1988-05-01 00:00:00
abstract::A single intradermal administration of recombinant interleukin-7 (IL-7) has been shown to aggravate the course of murine schistosomiasis, to favor the development of Th2-associated antibodies specific for the parasite, and to alter migration kinetics and/or migratory route of the parasite within its vertebrate host. H...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.67.8.4183-4190.1999
更新日期:1999-08-01 00:00:00
abstract::Wild-type Vibrio cholerae of both El Tor and classical biotypes (strains N16961 and 395, respectively) and nonmotile mutant derivatives with and without flagellar structures were characterized in three different animal models: (i) the rabbit ileal loop, (ii) the removable intestinal tie adult rabbit diarrhea (RITARD) ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.59.8.2727-2736.1991
更新日期:1991-08-01 00:00:00
abstract::Two virulence factors of Listeria monocytogenes, listeriolysin O (LLO) and phosphatidylinositol-specific phospholipase C (PI-PLC), mediate escape of this pathogen from the phagocytic vacuole of macrophages, thereby allowing the bacterium access to the host cell cytosol for growth and spread to neighboring cells. We ch...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.73.10.6639-6646.2005
更新日期:2005-10-01 00:00:00
abstract::Transposon Tn916 was used to insertionally inactivate a coaggregation-relevant locus of Streptococcus gordonii DL1 (Challis). One mutant (F11) was isolated that lost the ability to coaggregate with the streptococcal partners of DL1 but retained the ability to coaggregate with partners belonging to other genera. A prob...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.64.10.4137-4142.1996
更新日期:1996-10-01 00:00:00
abstract::The type III secretion system (TTSS) of Pseudomonas aeruginosa is induced in vivo upon contact with eukaryotic cells and in vitro by calcium depletion in culture medium. We have observed a previously identified protein, PsrA, necessary for full activation of TTSS gene expression in P. aeruginosa. Electrophoretic mobil...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.74.2.1121-1129.2006
更新日期:2006-02-01 00:00:00