Abstract:
:The obligate intracellular parasite Toxoplasma gondii can actively infect any nucleated cell type, including cells from the immune system. The rapid transfer of T. gondii from infected dendritic cells to effector natural killer (NK) cells may contribute to the parasite's sequestration and shielding from immune recognition shortly after infection. However, subversion of NK cell functions, such as cytotoxicity or production of proinflammatory cytokines, such as gamma interferon (IFN-γ), upon parasite infection might also be beneficial to the parasite. In the present study, we investigated the effects of T. gondii infection on NK cells. In vitro, infected NK cells were found to be poor at killing target cells and had reduced levels of IFN-γ production. This could be attributed in part to the inability of infected cells to form conjugates with their target cells. However, even upon NK1.1 cross-linking of NK cells, the infected NK cells also exhibited poor degranulation and IFN-γ production. Similarly, NK cells infected in vivo were also poor at killing target cells and producing IFN-γ. Increased levels of transforming growth factor β production, as well as increased levels of expression of SHP-1 in the cytosol of infected NK cells upon infection, were observed in infected NK cells. However, the phosphorylation of STAT4 was not altered in infected NK cells, suggesting that transcriptional regulation mediates the reduced IFN-γ production, which was confirmed by quantitative PCR. These data suggest that infection of NK cells by T. gondii impairs NK cell recognition of target cells and cytokine release, two mechanisms that independently could enhance T. gondii survival.
journal_name
Infect Immunjournal_title
Infection and immunityauthors
Sultana MA,Du A,Carow B,Angbjär CM,Weidner JM,Kanatani S,Fuks JM,Muliaditan T,James J,Mansfield IO,Campbell TM,Liu L,Kadri N,Lambert H,Barragan A,Chambers BJdoi
10.1128/IAI.00069-17subject
Has Abstractpub_date
2017-09-20 00:00:00issue
10eissn
0019-9567issn
1098-5522pii
IAI.00069-17journal_volume
85pub_type
杂志文章abstract::Streptococcus pneumoniae infections of the lung are associated with significant damage to the alveolar epithelium. Host phagocytes and pneumolysin, a cytolytic toxin of S. pneumoniae, are believed to contribute to this cellular damage, yet experiments in which these elements are absent demonstrate the presence of an a...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.61.10.4392-4397.1993
更新日期:1993-10-01 00:00:00
abstract::The pulmonary immune response protects healthy individuals against Pneumocystis pneumonia (PcP). However, the immune response also drives immunopathogenesis in patients who develop severe PcP, and it is generally accepted that optimal treatment requires combination strategies that promote fungal killing and also provi...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.00640-19
更新日期:2020-01-22 00:00:00
abstract::Genomics revealed the sequence of 3924 genes of the H37Rv strain of Mycobacterium tuberculosis. Proteomics complements genomics in showing which genes are really expressed, and here we show the expression of six genes not predicted by genomics, as proved by two-dimensional electrophoresis and matrix-assisted laser des...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.69.9.5905-5907.2001
更新日期:2001-09-01 00:00:00
abstract::One major outer membrane protein (P1) of Haemophilus influenzae type b (Hib), with an apparent molecular weight of 34,000 (34K) as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), has been shown to be heat modifiable. After heating at 100 degrees C for 5 min in 2% SDS, the P1 protein...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.55.12.2993-3000.1987
更新日期:1987-12-01 00:00:00
abstract::The virulence of Candida albicans in a mouse model of invasive candidiasis is dependent on the phospholipids phosphatidylserine (PS) and phosphatidylethanolamine (PE). Disruption of the PS synthase gene CHO1 (i.e., cho1Δ/Δ) eliminates PS and blocks the de novo pathway for PE biosynthesis. In addition, the cho1Δ/Δ muta...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.01612-14
更新日期:2014-10-01 00:00:00
abstract::Normal ICR mice were infected intravenously, intraperitoneally, or aerogenically with Pasteurella multocida strains isolated from a turkey (S68), calf (V90), or rabbit (J20) lung. Both the turkey and calf isolates were highly virulent for mice and multiplied logarithmically in the lungs, liver, and spleen, resulting i...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.39.2.779-784.1983
更新日期:1983-02-01 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::Apical membrane antigen 1 (AMA1) is expressed on the surfaces of Plasmodium falciparum merozoites and is thought to play an important role in the invasion of erythrocytes by malaria parasites. To select for peptides that mimic conformational B-cell epitopes on AMA1, we screened a phage display library of >10(8) indivi...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.72.2.1126-1134.2004
更新日期:2004-02-01 00:00:00
abstract::Helicobacter pylori mutants devoid of urease activity fail to colonize the gastric mucosa of mice; however, the effect of decreased levels of urease on colonization has not been examined. The nixA gene, required for full urease activity, encodes a cytoplasmic membrane nickel transporter that imports nickel ions and le...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.70.2.685-691.2002
更新日期:2002-02-01 00:00:00
abstract::Chemiluminescence of human alveolar macrophages (AM) was evaluated in vitro. Unstimulated AM generated chemiluminescence that remained constant during incubation. Addition of heat-killed Staphylococcus aureus 502A (HKB) or a chemical agent, phorbol myristate acetate, produced high rates of chemiluminescence that were ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.17.1.117-120.1977
更新日期:1977-07-01 00:00:00
abstract::It was previously demonstrated that avirulent Mycoplasma gallisepticum strain R(high) (passage 164) is lacking three proteins that are expressed in its virulent progenitor, strain R(low) (passage 15). These proteins were identified as the cytadhesin molecule GapA, the putative cytadhesin-related molecule CrmA, and a c...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.70.12.6839-6845.2002
更新日期:2002-12-01 00:00:00
abstract::ExoU, a phospholipase injected into host cells by the type III secretion system of Pseudomonas aeruginosa, leads to rapid cytolytic cell death. Although the importance of ExoU in infection is well established, the mechanism by which this toxin kills host cells is less clear. To gain insight into how ExoU causes cell d...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.74.5.2552-2561.2006
更新日期:2006-05-01 00:00:00
abstract::Feto-placental infections represent a major cause of pregnancy complications, and yet the underlying molecular and cellular mechanisms of vertical transmission are poorly understood. Listeria monocytogenes, a facultative intracellular pathogen, is one of a group of pathogens that are known to cause feto-placental infe...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.72.1.489-497.2004
更新日期:2004-01-01 00:00:00
abstract::Streptococcus pneumoniae, a Gram-positive bacterial pathogen, causes pneumonia, meningitis, and septicemia. Innate immune responses are critical for the control and pathology of pneumococcal infections. It has been demonstrated that S. pneumoniae induces the production of type I interferons (IFNs) by host cells and th...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.01572-14
更新日期:2014-06-01 00:00:00
abstract::Urease activity has recently been shown to be an important virulence determinant for Helicobacter pylori, allowing it to survive the low pH of the stomach during colonization. Experimental murine infection with Helicobacter felis is now being used as a model for H. pylori infection to study the effects of vaccines, an...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.62.3.793-798.1994
更新日期:1994-03-01 00:00:00
abstract::Strains of Cryptococcus neoformans vary in resistance to phagocytosis in vitro. The binding of isolated capsular polysaccharide (CPS) to a capsule-free mutant of C. neoformans confers resistance to phagocytosis. The importance of capsule composition to differences among strains in susceptibility to phagocytosis was ev...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.57.12.3751-3756.1989
更新日期:1989-12-01 00:00:00
abstract::Several Shigella flexneri mutants with defects in aromatic amino acid and/or purine biosynthesis have been evaluated as vaccines in humans or in animal models. To be suitable as a vaccine, a mutant has to show virulence attenuation, minimal reactogenicity, and a good immunogenic potential in animal models. With this a...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.71.12.7002-7013.2003
更新日期:2003-12-01 00:00:00
abstract::Mice with a null deletion mutation in the gamma interferon (IFN-gamma) receptor gene were used to study the role of IFN-gamma responsiveness during experimental pulmonary cryptococcosis. Cryptococcus neoformans was inoculated intratracheally into mice lacking the IFN-gamma receptor gene (IFN-gammaR-/-) and into contro...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.73.3.1788-1796.2005
更新日期:2005-03-01 00:00:00
abstract::Neisseria gonorrhoeae enters cultured human mucosal cells following binding of a distinct gonococcal opacity (Opa) outer membrane protein to cell surface proteoglycan receptors. We examined the route of internalization that is activated by Opa-expressing gonococci (strain VP1). Microscopy of infected Chang epithelial ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.64.5.1621-1630.1996
更新日期:1996-05-01 00:00:00
abstract::Staphylococcus aureus is an important opportunistic pathogen and is the etiological agent of many hospital- and community-acquired infections. The golden pigment, staphyloxanthin, of S. aureus colonies distinguishes it from other staphylococci and related Gram-positive cocci. Staphyloxanthin is the product of a series...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.00838-16
更新日期:2017-01-26 00:00:00
abstract::Brucella spp. are intracellular bacteria that cause the most frequent zoonosis in the world. Although recent work has advanced the field of Brucella vaccine development, there remains no safe human vaccine. In order to produce a safe and effective human vaccine, the immune response to Brucella spp. requires greater un...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.00994-09
更新日期:2010-01-01 00:00:00
abstract::Antigen-presenting cells (APCs) are key players in the induction and regulation of immune responses. In Plasmodium falciparum malaria, determination of which cells and pathways are activated in the network of APCs remains elusive. We therefore investigated the effects of a controlled human malaria infection in healthy...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.00473-15
更新日期:2015-09-01 00:00:00
abstract::The antiphagocytic effect of the Staphylococcus aureus capsule is known to be related to its ability to interfere with opsonization by normal human serum. In this study, evidence is presented with isolated cell surface components which indicates that the capsule hinders opsonization by masking cell wall peptidoglycan....
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.23.2.502-508.1979
更新日期:1979-02-01 00:00:00
abstract::Conidia ingested by resident macrophages had an enhanced percentage of transformation to yeast cells compared with those in culture medium without macrophages. The yeast cells subsequently grew intracellularly by budding. Macrophages treated with cytokines from antigen-stimulated spleen cells from immunized mice signi...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.60.5.2096-2100.1992
更新日期:1992-05-01 00:00:00
abstract::Vaccine adjuvants exert critical and unique influences on the quality of immune responses induced during active immunizations. We investigated the mechanisms of action of immunological adjuvants in terms of their requirements for cytokine-mediated pathways for adjuvanticity. Antibody responses potentiated by several a...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.66.11.5329-5336.1998
更新日期:1998-11-01 00:00:00
abstract::Macrophages are critical mediators of innate immunity and must be overcome for bacterial pathogens to cause disease. The Gram-positive bacterium Staphylococcus aureus produces virulence factors that impede macrophages and other immune cells. We previously determined that production of the metabolic cofactor lipoic aci...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.00344-19
更新日期:2019-09-19 00:00:00
abstract::It was found that cells of Nocardia asteroides GUH-2 (virulent) were approximately 10 times more virulent than cells of N. asteroides 14759 (intermediate) and greater that 500 times more virulent than N. asteroides 10905 (avirulent) cells when early-stationary-phase cultures suspended in saline were injected intraven...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.16.3.995-1004.1977
更新日期:1977-06-01 00:00:00
abstract::A novel in vivo expression technology (IVET) was performed to identify Klebsiella pneumoniae CG43 genes that are specifically expressed during infection of BALB/c mice. The IVET employed a UDP glucose pyrophosphorylase (galU)-deficient mutant of K. pneumoniae which is incapable of utilizing galactose and synthesizing ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.69.11.7140-7145.2001
更新日期:2001-11-01 00:00:00
abstract::Bordetella pertussis 165-9K/129G, which produces a nontoxic form of pertussis toxin (PT), was used to prepare a whole-cell diphtheria-tetanus-pertussis (DTP) vaccine. The in vivo potency and the serological response induced by this vaccine were comparable to those of the conventional DTP vaccine which contains active ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.60.3.1150-1155.1992
更新日期:1992-03-01 00:00:00
abstract::Nonspecific cross-reacting antigen (NCA) is a well-characterized membrane glycoprotein on granulocytes, macrophages, and lung epithelium. Structural studies at the protein and genomic levels have revealed that NCA is a member of the immunoglobulin supergene family, and hybridization studies showed that the transcript ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.59.7.2485-2493.1991
更新日期:1991-07-01 00:00:00