Abstract:
:Although excystation is crucial to the initiation of infection by Giardia lamblia, little is known about the regulation of this important process. We have been able to reliably induce excystation in vitro by mimicking cyst passage through the stomach and upper small intestine by the exposure of in vitro-derived cysts to an acidic, reducing environment (stage I) followed by protease treatment at a slightly alkaline pH (stage II). Preexposure of cysts to polyclonal rabbit antiserum against purified cyst walls (PCWs) or to wheat germ agglutinin (WGA) inhibited excystation by > 90%. Adsorption of either ligand with PCWs eliminated inhibition, demonstrating specificity for cyst wall epitopes. Inhibition by WGA was reversed by either chitotriose or sialic acid, while inhibition by polyclonal antibodies against PCWs (anti-PCW) was reversed only by sialic acid, which also inhibited binding of both ligands to intact cysts and to cyst wall antigens in immunoblots. Binding of anti-PCW did not affect acidification of cyst cytoplasm during stage I. Exposure of cysts to anti-PCW and WGA prior to, but not after, stage II was sufficient to inhibit excystation, and inhibition could be partially reversed by increasing the protease concentration during stage II. A 7- to 10-fold higher proportion of WGA- and anti-PCW-treated cysts than control cysts remained intact after stage II. Our results suggest that these ligands, which bind cyst wall epitopes, inhibit excystation, most likely by interfering with proteolysis of cyst wall glycoproteins during stage II.
journal_name
Infect Immunjournal_title
Infection and immunityauthors
Meng TC,Hetsko ML,Gillin FDdoi
10.1128/IAI.64.6.2151-2157.1996subject
Has Abstractpub_date
1996-06-01 00:00:00pages
2151-7issue
6eissn
0019-9567issn
1098-5522journal_volume
64pub_type
杂志文章abstract::Protamines (salmine prepared from sperm DNA of salmon and clupeine from herring sperm), which are basic peptides rich in arginine, were found to inhibit the proteolytic activity of arginine-specific cysteine protease (RC-protease) from Porphyromonas gingivalis. Lineweaver-Burk plot analysis revealed that the protamine...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.67.9.4917-4920.1999
更新日期:1999-09-01 00:00:00
abstract::Escherichia coli F-18, isolated from the feces of a healthy human in 1977, is an excellent colonizer of the streptomycin-treated mouse large intestine and displays normal motility and chemotaxis ability. A chemotaxis-defective derivative of E. coli F-18, E, coli F-18 CheA-, and a nonflagellated derivative, E. coli F-1...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.58.9.2957-2961.1990
更新日期:1990-09-01 00:00:00
abstract::Severe combined immunodeficient beige mice were inoculated orally and intraperitoneally with a bovine strain of Mycobacterium paratuberculosis to explore their potential as laboratory animal models in the study of paratuberculosis (Johne's disease). Control animals were similarly inoculated with heat-killed M. paratub...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.60.10.4074-4079.1992
更新日期:1992-10-01 00:00:00
abstract::The gene encoding a nitric oxide reductase has been identified in Neisseria gonorrhoeae. The norB gene product shares significant identity with the nitric oxide reductases in Ralstonia eutropha and Synechocystis sp. and, like those organisms, the gonococcus lacks a norC homolog. The gonococcal norB gene was found to b...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.68.9.5241-5246.2000
更新日期:2000-09-01 00:00:00
abstract::Pasteurella multocida is the causative agent of a number of diseases in animals, including fowl cholera. P. multocida strains simultaneously express two lipopolysaccharide (LPS) glycoforms (glycoforms A and B) that differ only in their inner core structure. Glycoform A contains a single 3-deoxy-d-manno-octulosonic aci...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.00457-10
更新日期:2010-09-01 00:00:00
abstract::Light and electron microscopy with histochemical staining were used to estimate exopolysaccharide production by strains of viridans streptococci recovered from patients with endocarditis. Six strains were selected for study because they represented a wide range of in vitro polysaccharide production. By light microscop...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.43.1.359-367.1984
更新日期:1984-01-01 00:00:00
abstract::Shigella flexneri 2a is an invasive enteric pathogen that may produce diarrhea when ingested by human beings and subhuman primates. We have previously shown that shigella diarrhea correlates with water and electrolyte transport abnormalities in the jejunum and colon. Dysentery alone is associated only with colonic tra...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.14.2.368-371.1976
更新日期:1976-08-01 00:00:00
abstract::Pseudomonas aeruginosa bacteremia in cancer patients develops from initial gastrointestinal (GI) colonization with translocation into the bloodstream in the setting of chemotherapy-induced neutropenia and GI mucosal damage. We established a reproducible mouse model of P. aeruginosa GI colonization and systemic spread ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.73.4.2262-2272.2005
更新日期:2005-04-01 00:00:00
abstract::Serial passage of Cryptococcus neoformans in mice increases virulence relative to the nonpassaged line. Postpassaged lines showed no difference in the expression of most known virulence factors, with the exception that the more virulent lines had smaller capsules in vitro. These data imply that other mechanisms of vir...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.73.10.7047-7050.2005
更新日期:2005-10-01 00:00:00
abstract::Leptospirosis can activate inflammatory responses through Toll-like receptors (TLRs) and may cause renal tubulointerstitial fibrosis characterized by the accumulation of extracellular matrix (ECM). We have previously demonstrated that Leptospira santorosai serovar Shermani detergent extract stimulates ECM accumulation...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.01287-09
更新日期:2011-03-01 00:00:00
abstract::Loss of the actin filament capping protein CapG has no apparent effect on the phenotype of mice maintained under sterile conditions; however, bone marrow-derived macrophages from CapG(-/-) mice exhibited distinct motility defects. We examined the ability of CapG(-/-) mice to clear two intracellular bacteria, Listeria ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.71.11.6582-6590.2003
更新日期:2003-11-01 00:00:00
abstract::The gene products from an 8-kb region adjacent to the 3' end of the ptx operon are required by Bordetella pertussis for the export of pertussis holotoxin. At least one of these gene products (PtlC) is specifically required for the export of assembled holotoxin from the periplasmic space. ptlC mutants exhibit a 20-fold...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.63.10.3920-3926.1995
更新日期:1995-10-01 00:00:00
abstract::Clostridium difficile causes pseudomembranous colitis in humans. The enterotoxin (i.e., toxin A) from this organism is believed to be responsible for the initial intestinal pathology associated with this disease. Previous work shows that this toxin binds to carbohydrates that contain Gal alpha 1-3Gal beta 1-4GlcNAc. H...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.59.1.73-78.1991
更新日期:1991-01-01 00:00:00
abstract::Two extremely oxygen-sensitive strains of Clostridium sp., designated Clostridium E and P, were obtained from digestive microflora of conventional mice and found to constitute a barrier against Shigella flexneri SF-2 when associated in vivo with Escherichia coli K-12. These and other simplified fractions of the conven...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.17.2.415-424.1977
更新日期:1977-08-01 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::Peru-15 is a live attenuated oral vaccine derived from a Vibrio cholerae O1 El Tor Inaba strain by a series of deletions and modifications, including deletion of the entire CT genetic element. Peru-15 is also a stable, motility-defective strain and is unable to recombine with homologous DNA. We wished to determine whe...
journal_title:Infection and immunity
pub_type: 临床试验,杂志文章,随机对照试验
doi:10.1128/iai.70.4.1965-1970.2002
更新日期:2002-04-01 00:00:00
abstract::Lipopolysaccharide (LPS) is one of the most potent trigger substances for monocytes and macrophages causing secretion of tumor necrosis factor alpha (TNF-alpha) and other inflammatory mediators. The nature of the nuclear factors involved in human TNF-alpha gene regulation is still unknown. Nuclear factor kappa B (NF-k...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.63.4.1529-1534.1995
更新日期:1995-04-01 00:00:00
abstract::Several studies have demonstrated roles for eosinophils during innate and adaptive immune responses to helminth infections. However, evidence that eosinophils are capable of initiating an immune response to parasite antigens is lacking. The goal of the present in vitro study was to investigate the potential of eosinop...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.02067-05
更新日期:2006-06-01 00:00:00
abstract::Conditions for the release of streptococcal type 12 M protein from whole cells by cyanogen bromide are described; they demonstrated that methionine is not essential to the structural arrangements which account for some of its immunological and biological properties. The released M protein was separated from other prot...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.21.2.546-555.1978
更新日期:1978-08-01 00:00:00
abstract::Pseudomonas aeruginosa invades various epithelial cell types in vitro and in vivo. The P. aeruginosa genome possesses a gene (flhA) which encodes a protein that is believed to be part of the export apparatus for flagellum assembly and which is homologous to invA of Salmonella spp. Because invA is required for invasion...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.69.8.4931-4937.2001
更新日期:2001-08-01 00:00:00
abstract::Hot phenol-water extraction of smooth Brucella abortus and B. melitensis cells yielded a toxic fraction which was recovered from the phenol phase (fraction 5). Chemically, fractions 5 from both Brucella species were lipid-carbohydrate-protein-2 keto-3-deoxyoctulosonic acid complexes which were stable to heat and resis...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:
更新日期:1970-02-01 00:00:00
abstract::Glycosylation of the flagellar core proteins (FlaBs) was detected in Treponema pallidum Nichols and in the type or reference strains of seven oral Treponema species. In several nonmotile strains of oral treponemes, the FlaBs were undetectable by both antibody and glycan staining. In contrast, a spontaneous low-motilit...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.66.12.5751-5754.1998
更新日期:1998-12-01 00:00:00
abstract::Using the indirect fluorescein-labeled and indirect peroxidase-antiperoxidase-labeled immunohistochemical techniques, and utilizing both antiserum specific for the beta-subunit of choriogonadotropin and antiserum for the total hormone, we have demonstrated the presence of a choriogonadotropin-like immunoreactive mater...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.24.3.920-924.1979
更新日期:1979-06-01 00:00:00
abstract::Plasmodium ookinetes secrete chitinases to penetrate the acellular, chitin-containing peritrophic matrix of the mosquito midgut en route to invasion of the epithelium. Chitinases are potentially targets that can be used to block malaria transmission. We demonstrate here that chitinases of Plasmodium falciparum and P. ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.68.11.6461-6465.2000
更新日期:2000-11-01 00:00:00
abstract::Fab fragments prepared from the immunoglobulin G monoclonal antibody (MAb) 4C12, which reacts with a determinant expressed on the hyphal extension of germ tubes of Candida albicans, inhibited germ tube formation, but intact MAb 4C12 did not. Indirect immunofluorescence showed a punctate binding pattern on cells incuba...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.58.11.3810-3812.1990
更新日期:1990-11-01 00:00:00
abstract::Citrobacter rodentium, an attaching-effacing bacterial pathogen, establishes an acute infection of the murine colonic epithelium and induces a mild colitis in immunocompetent mice. This study describes the role of T-cell subsets and B lymphocytes in immunity to C. rodentium. C57Bl/6 mice orally infected with C. rodent...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.71.9.5077-5086.2003
更新日期:2003-09-01 00:00:00
abstract::Four mouse monoclonal antibodies have been developed which react with Mycobacterium tuberculosis antigen 5. Each of these monoclonal antibodies has been used to prepare immunoabsorbents, and antigen has been isolated from unheated M. tuberculosis H37Ra culture filtrate by affinity chromatography with these absorbents....
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.45.1.52-55.1984
更新日期:1984-07-01 00:00:00
abstract::Reduced-minus-oxidized difference spectra of sonically treated virulent Treponema pallidum disclosed cytochromes of the b anc c types as well as large amounts of flavoprotein. Difference spectra of the carbon monoxide-binding pigment identified cytochrome o as the terminal oxidase. Physiological reduction of the cytoc...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.16.3.885-890.1977
更新日期:1977-06-01 00:00:00
abstract::We used an in vitro opsonophagocytic killing assay to measure the functional activity of antibody directed at the mucoid exopolysaccharide (MEP) antigen expressed by Pseudomonas aeruginosa strains isolated from cystic fibrosis patients. Rabbit antibodies raised to purified MEP were able to mediate phagocytic killing i...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.49.2.281-285.1985
更新日期:1985-08-01 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