Abstract:
:Diverse pathogens have evolved to survive and replicate in the endosomes or phagosomes of the host cells and establish persistent infection. Ehrlichiae are Gram-negative, intracellular bacteria that are transmitted by ticks. Ehrlichiae reside in the endosomes of the host phagocytic or endothelial cells and establish persistent infection in their vertebrate reservoir hosts. CD4(+) T cells play a critical role in protection against phagosomal infections. In the present study, we investigated the expansion, maintenance, and functional status of antigen-specific CD4(+) T cells during persistent Ehrlichia muris infection in wild-type and interleukin-10 (IL-10)-deficient mice. Our study indicated that early induction of IL-10 led to reduced inflammatory responses and impaired bacterial clearance during persistent Ehrlichia infection. Notably, we demonstrated that the functional production of gamma interferon (IFN-γ) by antigen-specific CD4(+) T cells maintained during a persistent phagosomal infection progressively deteriorates. The functional loss of IFN-γ production by antigen-specific CD4(+) T cells was reversed in the absence of IL-10. Furthermore, we demonstrated that transient blockade of IL-10 receptor during the T cell priming phase early in infection was sufficient to enhance the magnitude and the functional capacity of antigen-specific effector and memory CD4(+) T cells, which translated into an enhanced recall response. Our findings provide new insights into the functional status of antigen-specific CD4(+) T cells maintained during persistent phagosomal infection. The study supports the concept that a better understanding of the factors that influence the priming and differentiation of CD4(+) T cells may provide a basis to induce a protective immune response against persistent infections.
journal_name
Infect Immunjournal_title
Infection and immunityauthors
Singh AK,Thirumalapura NRdoi
10.1128/IAI.02101-14subject
Has Abstractpub_date
2014-10-01 00:00:00pages
4092-103issue
10eissn
0019-9567issn
1098-5522pii
IAI.02101-14journal_volume
82pub_type
杂志文章abstract::Two Escherichia coli strains (B/M 369 and C-35) belonging to enteropathogenic serogroup O86 were isolated from patients with infantile diarrhea and studied with respect to their cellular adherence properties. Both strains exhibited adherence (Ad+) to HEp-2 and HeLa cell monolayers in vitro and expressed mannose-resist...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.58.4.1106-1113.1990
更新日期:1990-04-01 00:00:00
abstract::A chimeric recombinant protein composed of the lktA gene product from Pasteurella haemolytica fused to bovine interleukin-2 (IL-2) was made. The LKT-IL-2 chimera was compared with recombinant bovine IL-2 with regard to the ability to induce proliferative responses and LAK cell activity in bovine peripheral blood monon...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.60.2.565-570.1992
更新日期:1992-02-01 00:00:00
abstract::Monoclonal antibodies (MAbs) specific for Plasmodium falciparum rhoptry-associated protein 1 (RAP-1) were generated and tested for inhibition of parasite growth in vitro. The majority of indirect immunofluorescence assay (IFA)-positive MAbs raised against recombinant RAP-1 positions 23 to 711 (rRAP-1(23-711)) recogniz...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.69.4.2558-2568.2001
更新日期:2001-04-01 00:00:00
abstract::Rubella virus was capable of replicating in both unstimulated and phytohemagglutinin-stimulated cultures of human mononuclear blood cells. Monocyte-derived macrophages were the main cell type responsible for viral replication. The susceptibility of macrophages increased during cultivation. Phytohemagglutinin-stimulate...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.27.2.309-314.1980
更新日期:1980-02-01 00:00:00
abstract::C57BL/6 mice were infected intravenously with 6 X 10(3) Listeria monocytogenes organisms. As early as day 3 of infection, there was a marked reduction in the number of lymphocytes recovered from the peripheral blood, bone marrow, and thymuses of infected animals. Concomitantly, there was an increase in the number of s...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.45.2.372-377.1984
更新日期:1984-08-01 00:00:00
abstract::Splenic lymphocytes from cytomegalovirus-infected mice lost their in vitro proliferative responses to cytomegalovirus antigen within 3 h after in vivo treatment with antilymphocyte globulin and prednisolone. The response was inhibited when the agents were administered separately or together, and inhibition persisted t...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:
更新日期:1980-12-01 00:00:00
abstract::Detoxified mutants of the Escherichia coli heat-labile toxin (LT) act as mucosal adjuvants to intranasally presented coadministered antigens. Here, we compare the adjuvant activity of a panel of detoxified derivatives of LT, using both intranasal (i.n.) and oral (p.o.) routes of administration. The mutants used as adj...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.67.9.4400-4406.1999
更新日期:1999-09-01 00:00:00
abstract::Allergic-type immune responses, particularly immunoglobulin E (IgE), correlate with protective immunity in human schistosomiasis. To better understand the mechanisms of parasite elimination we examined the immune correlates of protection in baboons (Papio cynocephalus anubis), which are natural hosts for Schistosoma m...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.67.2.636-642.1999
更新日期:1999-02-01 00:00:00
abstract::The Lyme disease spirochete, Borrelia burgdorferi, is introduced into human hosts via tick bites. Among the cell types present in the skin which may initially contact spirochetes are mast cells. Since spirochetes are known to activate a variety of cell types in vitro, we tested whether B. burgdorferi spirochetes could...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.67.3.1107-1115.1999
更新日期:1999-03-01 00:00:00
abstract::The outer membrane proteins of Bordetella avium were examined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Sarkosyl-insoluble outer membrane protein-enriched profiles from 50 virulent B. avium isolates, containing major 21,000- and 37,000-molecular-weight proteins (21K and 37K proteins, respectively) ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.60.3.958-964.1992
更新日期:1992-03-01 00:00:00
abstract::Escherichia coli 536 (O6:K15:H31), which was isolated from a case of urinary tract infection, determines high nephropathogenicity in a rat pyelonephritis system as measured by renal bacterial counts 7 days after infection. The loss of S fimbrial adhesin formation (Sfa-) (mannose-resistant hemagglutination [Mrh-] and f...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.54.3.761-767.1986
更新日期:1986-12-01 00:00:00
abstract::Salmonella enterica serovar Pullorum is worldwide a poultry pathogen of considerable economic importance, particularly in those countries with a developing poultry industry. In addition to the characteristic high mortality rates among young chicks, one of the features of Salmonella serovar Pullorum infection is that i...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.69.12.7873-7879.2001
更新日期:2001-12-01 00:00:00
abstract::We examined the immunobiological responses to Histoplasma capsulatum in lungs of gamma interferon (IFN-gamma) knockout mice (GKO mice). Naive GKO mice succumbed by day 9 to intranasal challenge with 2.5 x 10(6) yeasts, whereas all wild-type (WT) mice survived for 45 days. Compared to lungs of WT mice, the lungs of acu...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.65.7.2564-2569.1997
更新日期:1997-07-01 00:00:00
abstract::Brucella abortus is a facultative intracellular bacterial pathogen that causes abortion in domestic animals and undulant fever in humans. The mechanism of virulence of Brucella spp. is not fully understood yet. Furthermore, genes that allow Brucella to reach the intracellular niche and to interact with host cells need...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.70.9.5036-5044.2002
更新日期:2002-09-01 00:00:00
abstract::We studied seven strains of group G streptococci isolated from clinically severe bacteremic infections in six intravenous drug abusers. These group G strains multiplied luxuriantly in fresh human blood. On electron microscopy, they exhibited surface fibrillae similar to those observed in M-protein-rich group A strepto...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.55.3.753-757.1987
更新日期:1987-03-01 00:00:00
abstract::The enzymes responsible for reducing H2O2 were surveyed in 49 strains of Leptospira by using semiquantitative assays for catalase and peroxidase. The survey revealed a differential distribution of catalase and peroxidase activities between the two leptospiral complexes. The pathogenic Leptospira interrogans strains ga...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.22.3.672-675.1978
更新日期:1978-12-01 00:00:00
abstract::Preexisting antivector immunity can severely compromise the ability of Salmonella enterica serovar Typhimurium live vaccines to induce protective CD8 T-cell frequencies after type III secretion system-mediated heterologous protein translocation in orally immunized mice. To circumvent this problem, we injected CpG DNA ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.00700-09
更新日期:2009-12-01 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::Although Salmonella enterica serovar Typhimurium can undergo phase variation to alternately express two different types of flagellin subunit proteins, FljB or FliC, no biological function for this phenomenon has been described. In this investigation, we constructed phase-locked derivatives of S. enterica serovar Typhi...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.69.5.3021-3030.2001
更新日期:2001-05-01 00:00:00
abstract::Outer membrane protein F (porin) was purified by extraction from polyacrylamide gels of cell envelope proteins of the Pseudomonas aeruginosa PAO1 strain. Rats were immunized intramuscularly with 25 micrograms of protein F on days 1 and 14 and then challenged on day 28 via intratracheal inoculation of bacterium-contain...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.56.5.1017-1022.1988
更新日期:1988-05-01 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::The outcome of coccidioidomycosis depends to a large extent on the effectiveness of the T-cell-mediated immune (CMI) response to the fungal pathogen. For this reason, identification of Coccidioides immitis antigens which stimulate T cells is important for understanding the nature of host defense against the organism a...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.66.2.424-431.1998
更新日期:1998-02-01 00:00:00
abstract::Natural bactericidal resistance to Mycobacterium bovis BCG is under the control of a single gene, designated Bcg. Lung granuloma formation in susceptible (Bcgs) and resistant (Bcgr) mice was studied in two sets of Bcg-congenic systems, namely, the BALB/c (Bcgs)-C.D2 (BALB/c.Bcgr) pair and the B10.A (Bcgs)-B10.Ar (Bcgr...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.58.5.1210-1216.1990
更新日期:1990-05-01 00:00:00
abstract::Dentilisin is a major surface protease and virulence factor of the bacterium Treponema denticola. In this study, we found that T. denticola reduced inflammatory cytokines, including interleukin-1beta (IL-1beta), IL-6, and tumor necrosis factor alpha, in peripheral blood mononuclear cells through degradation by dentili...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.74.4.2462-2467.2006
更新日期:2006-04-01 00:00:00
abstract::Five monoclonal antibodies (MAbs) were partially characterized and tested for their ability to inhibit penetration of Madin-Darby bovine kidney (MDBK) cells by sporozoites of Eimeria bovis. By indirect fluorescent-antibody assays, all MAbs reacted with acetone-fixed sporozoites, but only two MAbs, EbS9 (immunoglobulin...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.56.10.2538-2543.1988
更新日期:1988-10-01 00:00:00
abstract::Vesicular stomatitis virus (Indiana strain) will only grow in T lymphocytes which have been stimulated to undergo cell division. Evidence is presented that a considerable enrichment of the vesicular stomatitis virus-replicating T cells may be accomplished in the mouse spleen by passing the spleen cells over glass wool...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.32.1.169-172.1981
更新日期:1981-04-01 00:00:00
abstract::The influence of D-alanine and carbohydrate substitution of lipoteichoic acids (LTAs) on the binding of antibody directed to the polyglycerol phosphate (PGP) portion was found to be at least partially dependent upon the mode of presentation of the antigen. There were greater differences in binding of anti-PGP immunogl...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.41.2.549-555.1983
更新日期:1983-08-01 00:00:00
abstract::Nontypeable Haemophilus influenzae (NTHi) causes repeated respiratory infections in patients with chronic lung diseases. These infections are characterized by a brisk inflammatory response which results in the accumulation of polymorphonucleated cells in the lungs and is dependent on the expression and secretion of pr...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.68.8.4430-4440.2000
更新日期:2000-08-01 00:00:00
abstract::Bacteroides spp. may contribute to the chronicity of mixed infections by affecting the normal functions of polymorphonuclear leukocytes (PMN). This study evaluated the physiologic and biochemical responses of human peripheral blood PMN to a variety of strains of the oral periodontal pathogen Porphyromonas (Bacteroides...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.59.9.3134-3142.1991
更新日期:1991-09-01 00:00:00
abstract::Leukosis viruses of seven subgroups were tested for oncogenicity in chickens susceptible to virus infection and to development of lymphoid leukosis (LL) tumors. All subgroup A viruses and the subgroup B virus tested produced a high incidence of LL and other related neoplasms. Viruses of subgroup C and RAV-61 of subgro...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.15.2.423-428.1977
更新日期:1977-02-01 00:00:00