Abstract:
:Pathogenic species of the spotted fever group Rickettsia are subjected to repeated exposures to the host complement system through cyclic infections of mammalian and tick hosts. The serum complement machinery is a formidable obstacle for bacteria to overcome if they endeavor to endure this endozoonotic cycle. We have previously demonstrated that that the etiologic agent of Mediterranean spotted fever, Rickettsia conorii, is susceptible to complement-mediated killing only in the presence of specific monoclonal antibodies. We have also shown that in the absence of particular neutralizing antibody, R. conorii is resistant to the effects of serum complement. We therefore hypothesized that the interactions between fluid-phase complement regulators and conserved rickettsial outer membrane-associated proteins are critical to mediate serum resistance. We demonstrate here that R. conorii specifically interacts with the soluble host complement inhibitor, factor H. Depletion of factor H from normal human serum renders R. conorii more susceptible to C3 and membrane attack complex deposition and to complement-mediated killing. We identified the autotransporter protein rickettsial OmpB (rOmpB) as a factor H ligand and further demonstrate that the rOmpB β-peptide is sufficient to mediate resistance to the bactericidal properties of human serum. Taken together, these data reveal an additional function for the highly conserved rickettsial surface cell antigen, rOmpB, and suggest that the ability to evade complement-mediated clearance from the hematogenous circulation is a novel virulence attribute for this class of pathogens.
journal_name
Infect Immunjournal_title
Infection and immunityauthors
Riley SP,Patterson JL,Martinez JJdoi
10.1128/IAI.00349-12subject
Has Abstractpub_date
2012-08-01 00:00:00pages
2735-43issue
8eissn
0019-9567issn
1098-5522pii
IAI.00349-12journal_volume
80pub_type
杂志文章abstract::Members of the babesial rhoptry-associated protein 1 (RAP-1) family express surface-exposed B-cell epitopes and are candidate antigens for vaccine development. The relationship between rap-1 genomic polymorphism and surface-exposed B-cell epitope expression was analyzed by comparison of biological clones of Mexico str...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.62.8.3576-3579.1994
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abstract::Pasteurella multocida is the causative agent of a number of diseases in animals, including fowl cholera. P. multocida strains simultaneously express two lipopolysaccharide (LPS) glycoforms (glycoforms A and B) that differ only in their inner core structure. Glycoform A contains a single 3-deoxy-d-manno-octulosonic aci...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.00457-10
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.62.9.3930-3936.1994
更新日期:1994-09-01 00:00:00
abstract::Rats and mice infected with Trypanosoma lewisi and Trypanosoma musculi, respectively, showed hyperreactivity to lipopolysaccharide (LPS) from gram-negative bacteria. Fatal shock could be precipitated with a dose of LPS 100 to 1,000 times less in infected compared with noninfected animals. In trypanosome-infected rats ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.46.2.501-506.1984
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.62.4.1236-1240.1994
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.71.12.6915-6920.2003
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.55.10.2509-2517.1987
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.67.6.2996-3001.1999
更新日期:1999-06-01 00:00:00
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journal_title:Infection and immunity
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doi:10.1128/IAI.66.8.3767-3774.1998
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.57.3.992-995.1989
更新日期:1989-03-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.56.4.1003-1006.1988
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doi:10.1128/IAI.01439-15
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.01397-13
更新日期:2014-05-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.68.8.4518-4522.2000
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.69.11.6776-6784.2001
更新日期:2001-11-01 00:00:00
abstract::Onchocerca volvulus, a human parasitic nematode, is the third leading cause of preventable blindness worldwide. This study describes the molecular cloning of a novel superoxide dismutase (SOD) from the parasite. This putative O. volvulus extracellular SOD (OvEcSOD) is 628 nucleotides (nt) long, including a 22-nt 5' sp...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.62.2.713-716.1994
更新日期:1994-02-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.62.1.145-151.1994
更新日期:1994-01-01 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.63.7.2403-2408.1995
更新日期:1995-07-01 00:00:00
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journal_title:Infection and immunity
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doi:10.1128/IAI.12.1.193-197.1975
更新日期:1975-07-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.17.1.136-139.1977
更新日期:1977-07-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.62.8.3521-3527.1994
更新日期:1994-08-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.00496-16
更新日期:2016-11-18 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.01564-13
更新日期:2014-04-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.73.10.6639-6646.2005
更新日期:2005-10-01 00:00:00
abstract::F344 rats chronically infected with Ureaplasma parvum develop two distinct profiles: asymptomatic urinary tract infection (UTI) and UTI complicated by struvite urolithiasis. To identify factors that affect disease outcome, we characterized the temporal host immune response during infection by histopathologic analysis ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.00458-09
更新日期:2009-10-01 00:00:00
abstract::Strain TG is a plasmidless exfoliative toxin (ET) producer. Strain ER201 contains a plasmid, whose loss had no apparent effect on ET production. The plasmid of ER201 was almost identical in size to the plasmid from strain UT0007, which carries an ET determinant. ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.14.5.1259-1260.1976
更新日期:1976-11-01 00:00:00
abstract::The route of pathogen inoculation by needle has been shown to influence the outcome of infection. Employing needle inoculation of the obligately intracellular parasite Leishmania major, which is transmitted in nature following intradermal (i.d.) deposition of parasites by the bite of an infected sand fly, we identifie...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.01600-13
更新日期:2014-07-01 00:00:00
abstract::We developed a porcine dermal explant model to determine the extent to which Staphylococcus aureus biofilm communities deplete oxygen, change pH, and produce damage in underlying tissue. Microelectrode measurements demonstrated that dissolved oxygen (DO) in biofilm-free dermal tissue was 4.45 ± 1.17 mg/liter, while DO...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.03075-14
更新日期:2015-06-01 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