Abstract:
:Variable subregions within the variant surface glycoprotein (VSG) coat displayed by African trypanosomes are predicted sites for T- and B-cell recognition. Hypervariable subregion 1 (HV-1) is localized to an internal amphipathic alpha helix in VSG monomers and may have evolved due to selective pressure by host T-cell responses to epitopes within this subregion. The prediction of T-cell receptor-reactive sites and major histocompatibility complex class II binding motifs within the HV-1 subregion, coupled with the conservation of amino acid residues in other regions of the molecule sufficient to maintain secondary and tertiary VSG structure, prompted us to test the hypothesis that Th cells may preferentially recognize HV-1 subregion peptides. Thus, we examined the fine specificity of VSG-specific T-cell lines, T-cell hybridomas, and Th cells activated during infection. Our results demonstrate that T-cell epitopes are distributed throughout the N-terminal domain of VSG but are not clustered exclusively within HV-1 or other hypervariable subregions. In contrast, T-cell-reactive sites were not detected within the relatively conserved C-terminal domain of VSG. Overall, this study is the first to dissect the fine specificity of T-cell responses to the trypanosome VSG and suggests that evolution of a conserved HV-1 region may be unrelated to selective pressures exerted by host T-cell responses. This study also demonstrates that T cells do not recognize the relatively invariant C-terminal region of the VSG molecule during infection, suggesting that it could serve as a potential subunit vaccine to provide variant cross-specific immunity for African trypanosomiasis.
journal_name
Infect Immunjournal_title
Infection and immunityauthors
Dagenais TR,Demick KP,Bangs JD,Forest KT,Paulnock DM,Mansfield JMdoi
10.1128/IAI.00729-08subject
Has Abstractpub_date
2009-01-01 00:00:00pages
141-51issue
1eissn
0019-9567issn
1098-5522pii
IAI.00729-08journal_volume
77pub_type
杂志文章abstract::Arg-gingipain (Rgp) and Lys-gingipain (Kgp) are Porphyromonas gingivalis cysteine proteinases implicated as major virulence factors in pathologies of periodontitis. We purified a 660-kDa cell-associated gingipain complex existing as a homodimer of two catalytically active monomers which comprises their catalytic and a...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.73.2.883-893.2005
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.55.8.1792-1800.1987
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abstract::Strains of Bacteroides fragilis that produce a ca. 20-kDa heat-labile protein toxin (termed B. fragilis toxin [BFT]) have been associated with diarrheal disease of animals and humans. BFT alters the morphology of intestinal epithelial cells both in vitro and in vivo and stimulates secretion in ligated intestinal segme...
journal_title:Infection and immunity
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doi:10.1128/IAI.65.3.1007-1013.1997
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abstract::Enterococcus faecalis strains are resident intestinal bacteria associated with invasive infections, inflammatory bowel diseases, and colon cancer. Although factors promoting E. faecalis colonization of intestines are not fully known, one implicated pathway is a phosphotransferase system (PTS) in E. faecalis strain OG1...
journal_title:Infection and immunity
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doi:10.1128/IAI.00080-19
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.60.5.1747-1755.1992
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abstract::Phagocytosis of unopsonized Salmonella typhimurium 395, MR-10, opsonized Salmonella typhimurium 395 MS, and Staphylococcus epidermidis by rabbit polymorphonuclear leukocytes was inhibited by heparin at concentrations as low as 0.5 U/ml. Inhibition was dose dependent and nearly complete at 20 U/ml. Provided that hepari...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.32.1.295-299.1981
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.59.5.1592-1598.1991
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.66.4.1473-1481.1998
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journal_title:Infection and immunity
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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
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journal_title:Infection and immunity
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journal_title:Infection and immunity
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doi:10.1128/IAI.00644-06
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journal_title:Infection and immunity
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journal_title:Infection and immunity
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doi:10.1128/IAI.67.8.3864-3871.1999
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.65.10.4299-4308.1997
更新日期:1997-10-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.67.10.5076-5082.1999
更新日期:1999-10-01 00:00:00
abstract::A solid-phase radioimmunoassay, applying whole Mycobacterium leprae as antigen and radiolabeled protein A from Staphylococcus aureus as antibody-detecting reagent, was used for the determination of specific immunoglobulin G (IgG) and IgM antibody responses in leprosy patients. High IgG anti-M. leprae antibody levels w...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.36.3.885-892.1982
更新日期:1982-06-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.9.1.34-40.1974
更新日期:1974-01-01 00:00:00
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journal_title:Infection and immunity
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.16.3.861-866.1977
更新日期:1977-06-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.69.1.479-485.2001
更新日期:2001-01-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.62.7.3008-3011.1994
更新日期:1994-07-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
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更新日期:2012-11-01 00:00:00
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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
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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
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.35.2.752-757.1982
更新日期:1982-02-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.67.3.1424-1431.1999
更新日期:1999-03-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.71.9.5077-5086.2003
更新日期:2003-09-01 00:00:00