Abstract:
:Whereas infections of macrophages by promastigote forms of Leishmania mexicana pifanoi induce the production of superoxide, infections by amastigotes barely induce superoxide production. Several approaches were employed to gain insight into the mechanism by which amastigotes avoid eliciting superoxide production. First, in experiments with nitroblue tetrazolium, we found that 25% of parasitophorous vacuoles (PVs) that harbor promastigotes are positive for the NADPH oxidase complex, in contrast to only 2% of PVs that harbor amastigotes. Second, confocal microscope analyses of infected cells labeled with antibodies to gp91phox revealed that this enzyme subunit is found in PVs that harbor amastigotes. Third, in immunoblots of subcellular fractions enriched with PVs from amastigote-infected cells and probed with antibodies to gp91phox, only the 65-kDa premature form of gp91phox was found. In contrast, subcellular fractions from macrophages that ingested zymosan particles contained both the 91- and 65-kDa forms of gp91phox. This suggested that only the immature form of gp91phox is recruited to PVs that harbor amastigotes. Given that gp91phox maturation is dependent on the availability of heme, we found that infections by Leishmania parasites induce an increase in heme oxygenase 1 (HO-1), the rate-limiting enzyme in heme degradation. Infections by amastigotes performed in the presence of metalloporphyrins, which are inhibitors of HO-1, resulted in superoxide production by infected macrophages. Taken together, we propose that Leishmania amastigotes avoid superoxide production by inducing an increase in heme degradation, which results in blockage of the maturation of gp91phox, which prevents assembly of the NADPH oxidase enzyme complex.
journal_name
Infect Immunjournal_title
Infection and immunityauthors
Pham NK,Mouriz J,Kima PEdoi
10.1128/IAI.73.12.8322-8333.2005keywords:
subject
Has Abstractpub_date
2005-12-01 00:00:00pages
8322-33issue
12eissn
0019-9567issn
1098-5522pii
73/12/8322journal_volume
73pub_type
杂志文章abstract::Brucella abortus and polyacrylic acid, two agents whose interferon-inducing capacity in the mouse has been well established, failed to stimulate circulating interferon production in rabbits, yet protected rabbits against local vaccinia virus infection. ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.8.4.669-673.1973
更新日期:1973-10-01 00:00:00
abstract::Gamma interferon (IFN-gamma)-primed human gingival fibroblasts (HGF) have been shown to produce higher levels of interleukin-8 (IL-8) upon stimulation with bacterial products and inflammatory cytokines than nonprimed controls. In this study, we examined whether priming of HGF with IFN-gamma up-regulates IL-8 productio...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.70.3.1272-1278.2002
更新日期:2002-03-01 00:00:00
abstract::Acquisition of immunity to Plasmodium falciparum sexual stages is a key determinant for reducing human-mosquito transmission by preventing the fertilization and the development of the parasite in the mosquito midgut. Naturally acquired immunity against sexual stages may therefore form the basis for the development of ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.05288-11
更新日期:2011-12-01 00:00:00
abstract::To assess the humoral immunological responses at the subclass level in shigellosis, specific antibody responses against Shigella dysenteriae 1 lipopolysaccharide (LPS), S. flexneri Y LPS, invasion plasmid-coded protein antigens (Ipa), and Shiga toxin were analyzed. Antibody responses of 41 patients with S. dysenteriae...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.63.5.2054-2061.1995
更新日期:1995-05-01 00:00:00
abstract::Rabbit lymphoid cells from spleen, peripheral blood, and peritoneal cavity lacked killer (K)-cell activity against cell lines of rabbit and human origin, including virus-infected human tumor cells. This lack of activity was not affected by antibody concentration, source of antibodies, effector/target cell ratio, or le...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.35.2.489-496.1982
更新日期:1982-02-01 00:00:00
abstract::Tularemia is caused by the Gram-negative bacterial pathogen Francisella tularensis Infection of macrophages and their subsequent death are believed to play important roles in the progression of disease. Because complement is a particularly effective opsonin for Francisella, we asked whether complement-dependent uptake...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.00424-17
更新日期:2017-09-20 00:00:00
abstract::Cell-associated hemagglutinin-negative mutants were derived from cholera enterotoxin-negative Vibrio cholerae JBK70 by Tn5 mutagenesis. One of the mutants identified, SB001, was characterized in greater detail. Its ability to colonize ilea of adult rabbits was determined by feeding approximately 10(8) V. cholerae to e...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.55.4.942-946.1987
更新日期:1987-04-01 00:00:00
abstract::A substance with potent decomplementation activity was isolated from staphylococcal culture supernatants by polyethylene glycol precipitation, DEAE-ion-exchange and Sephacryl chromatography, and preparative sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The purified substance exhibited all the characterist...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.47.1.47-51.1985
更新日期:1985-01-01 00:00:00
abstract::The leading malaria vaccine candidate, RTS,S, based on the Plasmodium falciparum circumsporozoite protein (CSP), will likely be the first publicly adopted malaria vaccine. However, this and other subunit vaccines, such as virus-vectored thrombospondin-related adhesive protein (TRAP), provide only intermediate to low l...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.01063-15
更新日期:2015-12-14 00:00:00
abstract::The nucleotide sequence of the chromosomal DNA flanking the Actinomyces naeslundii (formerly A. viscosus) T14V type 1 fimbrial structural subunit gene (fimP) was determined. Six open reading frames (ORFs), in the order 5' ORF3, ORF2, ORF1,fimP, ORF4, ORF5, ORF6 3', were identified. ORF1 encoded a protein of 408 amino ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.65.7.2629-2639.1997
更新日期:1997-07-01 00:00:00
abstract::The scrub typhus 58-kilodalton (kDa) antigen (Sta58) of Rickettsia tsutsugamushi is a major protein antigen often recognized by humans infected with scrub typhus rickettsiae. A 2.9-kilobase HindIII fragment containing a complete sta58 gene was cloned in Escherichia coli and found to express the entire Sta58 antigen an...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.58.5.1360-1368.1990
更新日期:1990-05-01 00:00:00
abstract::Guinea pig peritoneal or alveolar macrophages were inoculated with Mycoplasma pneumoniae cells. Extracellular mycoplasms were killed by complement treatment, and the effect of macrophage action on the number of the remaining viable mycoplasmas was observed. The complement killing was to some extent inhibited by the pr...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.25.1.11-15.1979
更新日期:1979-07-01 00:00:00
abstract::The ability of Klebsiella pneumoniae strains to resist the bactericidal activity of serum was quantitated. The K. pneumoniae strains tested included mutants lacking the capsular polysaccharide and mutants having a modified lipopolysaccharide structure. The last mutants were obtained as phage-resistant mutants, and the...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.54.1.85-89.1986
更新日期:1986-10-01 00:00:00
abstract::Three parameters of rotavirus infection, i.e., clinical disease, viral antigen in infected intestines, and infectious virus in feces, were assessed in infant mice nursed by mothers with or without preexisting rotavirus antibody. Diarrhea was the only consistent sign of clinical disease, and its course followed that of...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.38.2.755-763.1982
更新日期:1982-11-01 00:00:00
abstract::The effect of ingestion of heat-killed Histoplasma capsulatum yeast cells on the metabolism of arachidonic acid (20:4) to prostenoids and leukotrienes was examined in murine peritoneal macrophages (M phi s). H. capsulatum-containing M phi s exhibited a metabolite profile similar to that of zymosan-challenged phagocyte...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.60.7.2559-2564.1992
更新日期:1992-07-01 00:00:00
abstract::The present study examined the role of endogenous gamma interferon (IFN-gamma) in the formation of granulomas in mice which had been given a single intravenous injection of glycolipid-containing mycolic acid (trehalose 2,3,6'-trimycolate) purified from cell walls of Rhodococcus aurantiacus (Gordona aurantiaca) (GaGM) ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.61.7.2872-2878.1993
更新日期:1993-07-01 00:00:00
abstract::Previous reports from our laboratory have shown that 7 days after infection of C3HeB/FeJ mice with an attenuated strain of Salmonella typhimurium, there is profound suppression of responses to B- and T-cell mitogens and suppression of the capacity of spleen cells to mount a primary, in vitro plaque-forming-cell (PFC) ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.64.9.3786-3792.1996
更新日期:1996-09-01 00:00:00
abstract::The capacity of the intracellular pathogen Listeria monocytogenes to activate the alternative pathway of human complement was examined. Incubation of L. monocytogenes with human serum in optimal conditions (20% Mg2+EGTA [ethylene glycol-bis(beta-aminoethyl ether)-N,N,N',N'-tetraacetic acid]-chelated serum) consumed (3...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.61.12.5134-5139.1993
更新日期:1993-12-01 00:00:00
abstract::The method of hemagglutination inhibition was used to investigate the antigenic diversity of lipopolysaccharide (LPS) from Neisseria meningitidis and to develop a serotyping systems based on this antigen. The system uses outer membrane complex prepared by a simple extraction procedure to inhibit homologous hemagglutin...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.16.2.471-475.1977
更新日期:1977-05-01 00:00:00
abstract::Athymic BALB/c nude mice and euthymic BALB/c mice were infected with Rickettsia akari by the intraperitoneal route. The rickettsialpox infection was terminated in euthymic mice with only two intraperitoneal injections of the antibiotic oxytetracycline, whereas prolonged treatment was necessary to terminate the infecti...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:
更新日期:1980-05-01 00:00:00
abstract::The ultrastructural organization of Mycoplasma pneumoniae membranes and spatial relationships of this pathogen to epithelial cells in tracheal organ cultures were examined ultrastructurally by freeze-fracture techniques. Areas of morphologically distinct cell membrane variability characterized by membrane blebs and al...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:
更新日期:1980-09-01 00:00:00
abstract::The microbicidal myeloperoxidase (MPO)-H2O2-chloride system strongly inhibits Escherichia coli DNA synthesis. Also, cell envelopes from MPO-treated E. coli cells lose their ability to interact with hemimethylated DNA sequences of oriC, the chromosomal origin of replication, raising the prospect that suppression of DNA...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.66.6.2655-2659.1998
更新日期:1998-06-01 00:00:00
abstract::Chronic lung infection by Pseudomonas aeruginosa causes significant morbidity in cystic fibrosis patients initiated by the failure of innate immune responses. We used microarray analysis and real-time PCR to detect transcriptional changes associated with cytokine production in isogenic bronchial epithelial cell lines ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.73.10.6822-6830.2005
更新日期:2005-10-01 00:00:00
abstract::The role of the hypothalamus-pituitary-adrenal (HPA) axis in regulating the growth of Mycobacterium avium in Mycobacterium bovis BCG-resistant and -susceptible congenic mice was evaluated. Restraint was used to activate the HPA axis, which resulted in an increase in the level of corticosterone in the plasma. Activatio...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.61.11.4793-4800.1993
更新日期:1993-11-01 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::Slime production is not a generally recognized feature of Staphylococcus epidermidis. In a recent outbreak of S. epidermidis intravascular catheter-associated sepsis, we noted that 63% of clinically implicated strains grew as a slimy film coating the culture tube walls when propagated in tryptic soy broth. Only 37% of...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.37.1.318-326.1982
更新日期:1982-07-01 00:00:00
abstract::Sodium dodecyl sulfate-polyacrylamide gel electrophoresis patterns of proteins and externally exposed labeled surface constituents were analyzed in promastigotes of three etiological agents of kala azar (Leishmania donovani, HS70 strain from India; L. chagasi, Imperatriz strain from Brazil; L. infantum, ITMPA K263 str...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.50.1.136-141.1985
更新日期:1985-10-01 00:00:00
abstract::In Shigella flexneri a 220-kilobase plasmid encodes the ability to invade nonprofessional phagocytes by a mechanism similar to phagocytosis. In this report, the continuous macrophage cell line J774 was used to study the intracellular fate of both invasive and noninvasive strains. pWR100, the virulence plasmid of S. fl...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.55.3.521-527.1987
更新日期:1987-03-01 00:00:00
abstract::Calprotectin, an S100 calcium-binding protein with broad-spectrum antimicrobial activity in vitro, is expressed in neutrophils, monocytes, and gingival keratinocytes. In periodontitis, calprotectin appears upregulated and is detected at higher levels in gingival crevicular fluid and tissue specimens. How calprotectin ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.69.7.4242-4247.2001
更新日期:2001-07-01 00:00:00
abstract::Historically, Pneumocystis carinii pneumonia has been the most frequent cause of morbidity and mortality in patients with AIDS. Antiprotozoan drugs are effective in the treatment and prophylaxis of P. carinii pneumonia, which lends credence to the widely held view that P. carinii is a protozoan. However, recent geneti...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.60.10.4140-4145.1992
更新日期:1992-10-01 00:00:00