Abstract:
:In a model of experimental Chagas' disease induced with metacyclic forms of Trypanosoma cruzi, CD4+ but not CD8+ T cells undergo T-cell receptor (TCR)-CD3-mediated activation-induced cell death (AICD) in vitro. CD4+ T cells from T. cruzi-infected mice also developed unresponsiveness in proliferative responses to TCR-CD3-mediated stimulation. A linear correlation was found between extent of proliferative unresponsiveness and loss of CD4+ T-cell viability. CD4+ T-cell activation through the CD69 or Ly-6 A/E pathway, on the other hand, did not result in proliferative unresponsiveness compared with controls. Lack of suppression in proliferation assays correlated with lack of AICD by cells stimulated through the CD69 or Ly-6 A/E pathway. Concomitant stimulation through CD69, however, did not rescue CD4+ T cells from CD3-induced death. Flow cytometry study of cells stimulated in vitro showed no defect in interleukin-2 receptor expression by CD4+ T cells from infected donors, which escaped TCR-mediated AICD. In vivo injection of anti-CD3 into acutely infected mice, but not into control mice, led to splenocyte DNA fragmentation and failed to increase splenic CD4+ T-cell numbers. These results show that TCR-CD3-mediated AICD is involved in CD4+ T-cell unresponsiveness in vitro following infection with T. cruzi. In addition, successful activation of these cells through the CD69 and Ly-6 pathways is due to differences in the inability of these stimuli to trigger AICD. Since TCR-CD3-mediated AICD can be induced in vivo in infected mice, these findings may be relevant for the onset of immunological disturbances in the host.
journal_name
Infect Immunjournal_title
Infection and immunityauthors
Lopes MF,DosReis GAdoi
10.1128/IAI.64.5.1559-1564.1996subject
Has Abstractpub_date
1996-05-01 00:00:00pages
1559-64issue
5eissn
0019-9567issn
1098-5522journal_volume
64pub_type
杂志文章abstract::In mammalian hosts, Leishmania sp. parasites are obligatory intracellular organisms that invade macrophages and dendritic cells (DC), where they reside in endocytic organelles termed parasitophorous vacuoles (PV). Most of the present knowledge of the characteristics of PV harboring Leishmania sp. is derived from studi...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.74.2.1305-1312.2006
更新日期:2006-02-01 00:00:00
abstract::Archived sera (collected in 1946) from acute rheumatic fever (ARF) and untreated scarlet fever and/or pharyngitis patients were reacted with streptococcal M protein, cardiac myosin, and cardiac tropomyosin. Except for very low levels to tropomyosin, antibodies to other antigens were not elevated in the sera of ARF pat...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.68.12.7132-7136.2000
更新日期:2000-12-01 00:00:00
abstract::We examined the effect of protein kinase C (PKC) activation on the cyclic GMP response to heat-stable enterotoxin (STa) in a colonic carcinoma intestinal epithelial cell line, T84 cells. Our results demonstrate that the active phorbol ester analog, phorbol dibutyrate, but not the inactive alpha-phorbol dibutyrate, act...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.58.5.1402-1407.1990
更新日期:1990-05-01 00:00:00
abstract::Recognition of microbial patterns by host receptors is the first step in a multistep sequence leading to neutrophil-dependent host resistance. Although the role of membrane-bound sensors in bacterial recognition has been examined in detail, the importance of cytosolic sensors in the lungs is largely unexplored. In thi...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.05641-11
更新日期:2011-11-01 00:00:00
abstract::Porphyromonas gingivalis is a gram-negative anaerobic bacterium that is considered the key etiologic agent of chronic periodontitis. Arg- and Lys-gingipain cysteine proteinases produced by P. gingivalis are key virulence factors and are believed to be essential for significant tissue component degradation, leading to ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.72.8.4689-4698.2004
更新日期:2004-08-01 00:00:00
abstract::Toxoplasma gondii and Neospora caninum (both Apicomplexa) are closely related cyst-forming coccidian parasites that differ significantly in their host ranges and ability to cause disease. Unlike eutherian mammals, Australian marsupials (metatherian mammals) have long been thought to be highly susceptible to toxoplasmo...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.00173-17
更新日期:2017-05-23 00:00:00
abstract::Using a murine respiratory infection model, we have demonstrated previously that infection with Bordetella pertussis or immunization with a whole-cell pertussis vaccine induced antigen-specific Th1 cells, which conferred a high level of protection against aerosol challenge. In contrast, immunization with an acellular ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.64.12.5295-5301.1996
更新日期:1996-12-01 00:00:00
abstract::The kinetics of infection and the pathogenic effects on the reproductive function of laboratory mice infected with Bartonella birtlesii recovered from an Apodemus species are described. B. birtlesii infection, as determined by bacteremia, occurred in BALB/c mice inoculated intravenously. Inoculation with a low-dose in...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.69.9.5313-5317.2001
更新日期:2001-09-01 00:00:00
abstract::Free lipid A of Bordetella pertussis, Neisseria meningitidis, and Escherichia coli lipopolysaccharide (LPS) was prepared by hydrolysis in acetate buffer (pH 4.5); in addition, lipid A from B. pertussis and E. coli was prepared by hydrolysis in mineral acid (HCl). The precipitates obtained were purified by extraction m...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.54.2.465-471.1986
更新日期:1986-11-01 00:00:00
abstract::Cytoadherence-linked asexual gene 9 (Clag9), a conserved Plasmodium protein expressed during the asexual blood stages, is involved in the cytoadherence of infected red blood cells (RBCs) to the endothelial lining of blood vessels. Here, we show that Plasmodium falciparum Clag9 (PfClag9) is a component of the PfClag9-R...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.00504-19
更新日期:2020-01-22 00:00:00
abstract::In Pseudomonas aeruginosa, the second messenger cyclic-di-GMP and Gac/Rsm signaling pathways are associated with the transition from acute to chronic infection. Therefore, identification of the molecular mechanisms that govern lifestyle choice in bacteria is very important. Here, we identified a novel cyclic-di-GMP mo...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.00602-20
更新日期:2021-01-19 00:00:00
abstract::The major antigenic determinants of the lipoglycans from Acholeplasma granularum and Acholeplasma axanthum were found to be the oligosaccharide sequences Glcp(beta 1 leads to 2)-Glcp(alpha 1 leads to 4)-Glcp and Glcp(beta 1 leads to 2)-Glcp(beta 1 leads to 2)-Glcp, respectively. The disaccharides sophorose and maltose...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.40.2.629-632.1983
更新日期:1983-05-01 00:00:00
abstract::Purified group A streptococcal peptidoglycan-polysaccharide (PG-PS) fragments were either de-O-acylated, or acetylated and then de-O-acylated to yield N-acetylated PG-PS. Native PG-PS was poorly degraded, N-acetylated PG-PS was extensively degraded, and de-O-acylated PG-PS was only slightly degraded by hen egg white l...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.55.1.16-23.1987
更新日期:1987-01-01 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::Science has always been a competitive undertaking. Despite recognition of the benefits of cooperation and team science, reduced availability of funding and jobs has made science more competitive than ever. Here we consider the benefits of competition in providing incentives to scientists and the adverse effects of com...
journal_title:Infection and immunity
pub_type: 社论
doi:10.1128/IAI.02939-14
更新日期:2015-04-01 00:00:00
abstract::Antibody responses against proteins located on the surface or in the apical organelles of merozoites are presumed to be important components of naturally acquired protective immune responses against the malaria parasite Plasmodium falciparum. However, many merozoite antigens are highly polymorphic, and antibodies indu...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.73.1.422-430.2005
更新日期:2005-01-01 00:00:00
abstract::The role of type 1 pili in promoting bladder colonization was examined by constructing two mutant strains of a clinical Escherichia coli isolate. One mutant was isogenic to the parental strain save for a lesion in a gene required for pilus receptor binding; the other mutant was isogenic save for a lesion in the gene e...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.53.3.693-696.1986
更新日期:1986-09-01 00:00:00
abstract::The proinflammatory cytokine tumor necrosis factor alpha (TNF-alpha) induces lethal hepatitis when injected into D-(+)-galactosamine-sensitized mice on the one hand or systemic inflammatory response syndrome (SIRS) in normal mice on the other hand. We studied whether serum amyloid P component (SAP), the major acute-ph...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.68.9.5026-5029.2000
更新日期:2000-09-01 00:00:00
abstract::In this study, we examined the binding of Candida albicans synchronized yeast-phase cells to plastic, immobilized amino acids and bovine serum albumin (BSA) and quantified the binding by using an XTT tetrazolium salt assay and absorbance determination. Our results show that C. albicans binds efficiently and specifical...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.66.1.140-144.1998
更新日期:1998-01-01 00:00:00
abstract::The toxicity by inhalation of various gram-negative bacteria, isolated from settings associated with inhalation disease, was studied by a variety of means. These microorganisms were not equally toxic. Citrobacter freundii aerosol challenges of rabbits provoked significant (up to fivefold) increases in plasma haptoglob...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.40.1.133-138.1983
更新日期:1983-04-01 00:00:00
abstract::In previous studies, we reported that fibronectin (FN) markedly enhances phagocytic uptake of antibody-coated group B streptococci (GBS) by human polymorphonuclear leukocytes. Furthermore, administration of FN along with a GBS type-specific monoclonal or polyclonal antibody to infected neonatal rats significantly enha...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.61.6.2334-2339.1993
更新日期:1993-06-01 00:00:00
abstract::Vascular response is an essential aspect of an effective immune response to periodontal disease pathogens, as new blood vessel formation contributes to wound healing and inflammation. Gaining a greater understanding of the factors that affect vascular response may then contribute to future breakthroughs in dental medi...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.01305-15
更新日期:2016-06-23 00:00:00
abstract::Subtilase cytotoxin (SubAB) is a recently identified AB5 subunit toxin produced by Shiga-toxigenic Escherichia coli. The A subunit is thought to be a subtilase-like, serine protease, whereas the B subunit binds to the toxin receptor on the cell surface. We cloned the genes from a clinical isolate; the toxin was produc...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.01336-06
更新日期:2007-01-01 00:00:00
abstract::Glucan-binding protein B (GbpB) from Streptococcus mutans has been shown to induce protective immunity to dental caries in experimental models. Having recently sequenced the gbpB gene, our objective in this study was to identify immunogenic regions within the GbpB sequence for use in subunit vaccines. Potential region...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.71.3.1179-1184.2003
更新日期:2003-03-01 00:00:00
abstract::Pseudomonas aeruginosa is a leading cause of hospital-acquired pneumonia and chronic lung infections in cystic fibrosis patients. Iron is essential for bacterial growth, and P. aeruginosa expresses multiple iron uptake systems, whose role in lung infection deserves further investigation. P. aeruginosa Fe(3+) uptake sy...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.00098-16
更新日期:2016-07-21 00:00:00
abstract::Arg-gingipains are extracellular cysteine proteases produced by the gram-negative periodontal pathogen Porphyromonas gingivalis and are encoded by rgpA and rgpB. Three Arg-gingipains, heterodimeric high-molecular-mass Arg-gingipain HRgpA comprising the alpha-catalytic chain and the beta-adhesin chain, the monomeric so...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.73.8.4864-4878.2005
更新日期:2005-08-01 00:00:00
abstract::In the mouse model of Lyme borreliosis, the host immune response during infection with Borrelia burgdorferi results in the remission of carditis and arthritis, as well as global reduction of spirochete numbers in tissues, without elimination of infection. These events were recapitulated by passive transfer of immune s...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.00469-06
更新日期:2006-08-01 00:00:00
abstract::Previous examination of thin sections of L929 cells heavily infected with the Q fever Priscilla isolate by conventional transmission electron microscopy indicated that the rickettsiae resided within multiple vacuoles. The present study using high-voltage electron microscopy and three-dimensional reconstruction reveale...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.61.10.4485-4488.1993
更新日期:1993-10-01 00:00:00
abstract::Human sera were examined by an enzyme-linked immunosorbent assay for immunoglobulin G (IgG) and IgM antibodies to purified type III polysaccharide of group B streptococci. The antigen-binding capacity of a reference human serum was determined by a radioimmunoassay, and the total antibody content was determined by quan...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.46.1.98-104.1984
更新日期:1984-10-01 00:00:00
abstract::We are currently studying the soluble egg antigens of Schistosoma japonicum in an attempt to determine which antigens are potent immunogens. Previously, we demonstrated by Ouchterlony immunodiffusion and inhibition of the circumoval precipitin test that the glycoprotein fraction of soluble egg antigens contains the an...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.34.2.397-406.1981
更新日期:1981-11-01 00:00:00