Abstract:
:Once in the cytoplasm of mammalian cells, Shigella flexneri expresses a motile phenotype caused by polar directional assembly of actin. This process depends on accumulation of IcsA (VirG), a 120-kDa protein with ATPase activity, at the pole of the bacterium opposite to that at which ongoing septation occurs. IcsA is also secreted into the bacterial supernatant as a 95-kDa species, after cleavage at an SSRRASS sequence which, when mutagenized, blocks processing. MAbF15, an anti-IcsA monoclonal antibody, recognizes an epitope located within repeated Gly-rich boxes in the N-terminal half of the protein. We used this monoclonal antibody to visualize the location of a noncleavable 120-kDa IcsA mutant protein expressed in S. flexneri. We found that this noncleavable IcsA protein no longer localized exclusively to the pole of the bacterium but also could be detected circumferentially. Whereas the monoclonal antibody detected the wild-type cleavable form of IcsA in only 40% of the cells expressing this protein, the noncleavable was easily detectable in all the cells carrying the icsA mutant allele. Similar aberrant localization of the IcsA mutant protein on bacteria growing within the cytoplasm of HeLa cells was observed. The strains expressing the noncleavable IcsA protein expressed abnormal intracellular movement and were often observed moving in a direction perpendicular to their longitudinal axis. The putative protease which processes IcsA may therefore play a role in achieving polar expression of this protein and providing maximum asymmetry essential to directional movement. In addition, MAbF15 allowed us to identify a 70-kDa eukaryotic protein cross-reacting with IcsA. This protein accumulated in the actin tails of motile bacteria and in membrane ruffles of the cells.
journal_name
Infect Immunjournal_title
Infection and immunityauthors
d'Hauteville H,Dufourcq Lagelouse R,Nato F,Sansonetti PJdoi
10.1128/IAI.64.2.511-517.1996subject
Has Abstractpub_date
1996-02-01 00:00:00pages
511-7issue
2eissn
0019-9567issn
1098-5522journal_volume
64pub_type
杂志文章abstract::In this study, the role of the hepatobiliary system in the early pathogenesis of Salmonella enteritidis infection was investigated in a rat model. Intravenous (i.v.) challenge with lipopolysaccharide (LPS) has previously been shown to enhance the translocation of normal gut flora. We first confirmed that LPS can simil...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.68.1.1-5.2000
更新日期:2000-01-01 00:00:00
abstract::Conventional dendritic cells (cDCs) are critical for protection against pulmonary infection with the opportunistic fungal pathogen Cryptococcus neoformans; however, the role of plasmacytoid dendritic cells (pDCs) is unknown. We show for the first time that murine pDCs have direct activity against C. neoformans via rea...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.00103-16
更新日期:2016-08-19 00:00:00
abstract::We have previously shown that individuals infected with Chlamydia trachomatis can develop a robust antibody response to a chlamydia-secreted protein (designated chlamydial proteasome/protease-like activity factor [CPAF]). We now report that sera collected from these infected individuals neutralized the proteolytic act...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.73.7.4414-4419.2005
更新日期:2005-07-01 00:00:00
abstract::An attenuated influenza A candidate vaccine virus, derived from the A/Ann Arbor/6/60 (H2N2) cold-adapted (ca) donor virus and the A/Alaska/6/77 (H3N2) wild-type virus, was evaluated in adult seronegative volunteers (serum hemagglutination-inhibiting antibody titer, less than or equal to 1:8) for level of attenuation, ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.40.3.1044-1051.1983
更新日期:1983-06-01 00:00:00
abstract::Proteins from human polymorphonuclear leukocyte granules were extracted with 0.2 M acetate, pH 4.0, and fractionated by Sephadex G-100 column chromatography. The fractions demonstrated selective bactericidal action against a deep rough cell wall mutant of Escherichia coli O111:B4 with rough lipopolysacharide and cell ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.23.3.587-591.1979
更新日期:1979-03-01 00:00:00
abstract::Chlamydia trachomatis is an obligate intracellular pathogen that causes sexually transmitted disease. In women, chlamydial infections may cause pelvic inflammatory disease (PID), ectopic pregnancy, and infertility. The role of antibodies in protection against a primary Chlamydia infection is unclear and was a focus of...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.00413-20
更新日期:2020-12-15 00:00:00
abstract::Treatment with nontoxic monophosphoryl lipid A (MPL), which was derived from a polysaccharide-deficient, heptoseless Re mutant of Salmonella typhimurium, was found to inactivate suppressor T-cell activity, as evidenced by a decrease in the degree of low-dose immunological paralysis expressed and an increase in the mag...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.56.5.1076-1083.1988
更新日期:1988-05-01 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::One-day-old chicks were infected orally with two strains of weakly hemolytic spirochetes isolated from a human and a pig with intestinal spirochetosis. These spirochetosis both colonized birds, attached end-on to their cecal enterocytes, induced watery diarrhea, and significantly depressed growth rates. Cultures of Se...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.63.9.3705-3710.1995
更新日期:1995-09-01 00:00:00
abstract::The response of ferrets after intranasal inoculation of inactivated A/Hong Kong/68 (H3N2) influenza virus vaccines is reported. Normal ferrets given either saline vaccine in drops or freeze-dried vaccine in an aerosol intranasally did not produce detectable serum or nasal hemagglutination inhibiting antibody and were ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.9.6.985-990.1974
更新日期:1974-06-01 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::To characterize the mechanism by which interleukin 10 (IL-10) inhibits Th1 responses to intracellular pathogens, we evaluated the interaction between IL-10 and Mycobacterium tuberculosis-induced gamma interferon (IFN-gamma) production by peripheral blood mononuclear cells from persons across the spectrum of tuberculou...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.64.3.913-918.1996
更新日期:1996-03-01 00:00:00
abstract::During the course of infection of rabbits with vaccinia virus, macrophages obtained from the peritoneal cavity develop bactericidal activity and the replication of vaccinia virus becomes restricted in these cells. The abortive replication of vaccinia virus in the activated macrophages was characterized in the present ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.26.1.328-338.1979
更新日期:1979-10-01 00:00:00
abstract::Nontypeable Haemophilus influenzae (NTHi) initiates infection by colonizing the upper respiratory tract and is a common cause of localized respiratory tract disease. Previous work has established that the NTHi HMW1 and HMW2 proteins are potent adhesins that mediate efficient in vitro adherence to cultured human respir...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.00153-16
更新日期:2016-09-19 00:00:00
abstract::The major outer membrane protein (P2) of Haemophilus influenzae type b (Hib) with an apparent molecular weight of 37,000 to 40,000 has been previously shown to function as a porin and also as a target for antibodies protective against experimental Hib disease. The gene encoding the Hib P2 protein was cloned by using a...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.56.10.2709-2716.1988
更新日期:1988-10-01 00:00:00
abstract::The majority of strains of Actinobacillus actinomycetemcomitans isolated from patients with periodontal diseases secrete a leukotoxin that destroys human myeloid cells within minutes but has no effect on viability of peripheral blood lymphocytes in culture for 1.5 h. However, since this organism persists in the gingiv...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.59.9.3267-3272.1991
更新日期:1991-09-01 00:00:00
abstract::The genetics of resistance to a naturally occurring respiratory infection caused by Sendai virus was examined in F1, F2, and backcross progeny of resistant C57BL/6J and susceptible DBA/2J mice and in 25 recombinant inbred strains. An intranasal inoculum of 0.1 50% tissue culture infective dose (low dose) of Sendai vir...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.41.1.308-312.1983
更新日期:1983-07-01 00:00:00
abstract::The immunostimulation provided by the mycobacterial cell wall has been exploited for many decades, e.g., in Freund's complete adjuvant. Recently, the underlying mechanism behind this adjuvant activity, including Toll receptor signaling, has begun to be unraveled, confirming the potential of mycobacterial constituents ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.73.9.5817-5826.2005
更新日期:2005-09-01 00:00:00
abstract::Transposon mutagenesis was used to analyze Mycoplasma pneumoniae cytadherence. Mycoplasmas were electroporated with Tn4001, and transformants were identified by antibiotic selection using gentamicin. The resulting colonies were screened for hemadsorption (HA) as an indicator for cytadherence. Six HA- colonies from ind...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.63.9.3479-3483.1995
更新日期:1995-09-01 00:00:00
abstract::At least 10 of 11 demonstrable antigens in unheated culture filtrates of 12 vaccine strains of BCG were shared as determined in a reference antigen-antibody immunoelectrophoresis system. Filtrates from each of the BCG strains gave equivalent skin test reactions in homologously and heterologously sensitized guinea pigs...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.7.5.777-780.1973
更新日期:1973-05-01 00:00:00
abstract::Total and insoluble dextransucrase activities were measured in cell-associated and supernatant fractions of Streptococcus mutans GS-5 grown in several media. Although the amount of cell-associated and supernatant activity varied greatly as a function of medium, the total activity appeared constant. The distribution of...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.18.3.629-635.1977
更新日期:1977-12-01 00:00:00
abstract::The M1inv+ subclone of M1 group A streptococci that spread globally in the late 1980s and early 1990s was previously identified by restriction fragment length polymorphism (RFLP), M protein, and SpeA exotoxin sequence analyses. Strains representing this subclone were characterized with regard to carriage of bacterioph...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.66.11.5592-5597.1998
更新日期:1998-11-01 00:00:00
abstract::Di-, tri-, and tetrasaccharides, synthesized according to the chemical structure of pneumococcal polysaccharide type 3 (PS3), were coupled to the cross-reactive material (CRM(197)) of modified diphtheria toxin in different molar carbohydrate/protein ratios using the squarate coupling method. To study protective immuni...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.69.7.4698-4701.2001
更新日期:2001-07-01 00:00:00
abstract::Recent efforts to develop a vaccine against the diarrheal disease cholera have focused on the use of live attenuated strains of the causative organism, Vibrio cholerae. The Ogawa lipopolysaccharide phenotype is expressed by many epidemic strains, and motility defects reduce the risk of reactive diarrhea in vaccine rec...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.68.11.6391-6397.2000
更新日期:2000-11-01 00:00:00
abstract::Neonatal administration of 16 mg of cyclophosphamide in inbred chickens resulted in a transient, but profound, deficiency in the in vitro proliferative response of spleen cells. Functional T-cell deficiency was accompanied by a marked morphological degeneration in the thymus and thymus-dependent areas in the spleen. ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.17.1.227-230.1977
更新日期:1977-07-01 00:00:00
abstract::Ehrlichia chaffeensis, a tick-transmitted rickettsial, is the causative agent of human monocytic ehrlichiosis. To examine protein expression patterns, we analyzed total, membrane, and immunogenic proteomes of E. chaffeensis originating from macrophage and tick cell cultures. Total proteins resolved by one-dimensional ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.00484-08
更新日期:2008-11-01 00:00:00
abstract::An attenuated Salmonella typhi Ty21a vaccine was administered to 18 infants and toddlers (less than or equal to 24 months old) to determine its safety and immunogenicity. The vaccination (10(9) CFU per dose, three doses) was well tolerated. However, after the vaccination there was no evidence of a humoral or cellular ...
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.59.11.4291-4293.1991
更新日期:1991-11-01 00:00:00
abstract::The fungus Cryptococcus neoformans has emerged as a major cause of meningoencephalitis worldwide. Host response to the fungus involves both innate and adaptive immunity, but fungal genes that modulate these processes are poorly understood. Previous studies demonstrated attenuated virulence of a mutant of a virulence-a...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.00821-12
更新日期:2013-03-01 00:00:00
abstract::Antiserum and purified immunoglobulin directed against Mycoplasma pneumoniae membrane protein P1 were examined for their influence on mycoplasma viability, metabolism, and cytadsorption. Anti-P1 immunoglobulin inhibited adherence of M. pneumoniae to hamster tracheal rings in vitro by up to 80% and inhibited hemadsorpt...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.39.3.1180-1186.1983
更新日期:1983-03-01 00:00:00
abstract::Coxiella burnetii, phase I and II, cells cultivated in the yolk sac of chicken embryos were separated from host cell components by two cycles of isopycnic Renografin gradient centrifugation. Initial steps in the purification of viable C. burnetii involved differential centrifugation and sedimentation through an aqueou...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.32.2.840-851.1981
更新日期:1981-05-01 00:00:00