Abstract:
:Strain superinfection occurs when a second pathogen strain infects a host already infected with a primary strain. The selective pressures that drive strain divergence, which underlies superinfection, and allow penetration of a new strain into a host population are critical knowledge gaps relevant to shifts in infectious disease epidemiology. In regions of endemicity with a high prevalence of infection, broad population immunity develops against Anaplasma marginale, a highly antigenically variant rickettsial pathogen, and creates strong selective pressure for emergence of and superinfection with strains that differ in their Msp2 variant repertoires. The strains may emerge either by msp2 locus duplication and allelic divergence on an existing genomic background or by introduction of a strain with a different msp2 allelic repertoire on a distinct genomic background. To answer this question, we developed a multilocus typing assay based on high-throughput sequencing of non-msp2 target loci to distinguish among strains with different genomic backgrounds. The technical error level was statistically defined based on the percentage of perfect sequence matches of clones of each target locus and validated using experimental single strains and strain pairs. Testing of A. marginale-positive samples from tropical regions where A. marginale infection is endemic identified individual infections that contained unique alleles for all five targeted loci. The data revealed a highly significant difference in the number of strains per animal in the tropical regions compared to infections in temperate regions and strongly supported the hypothesis that transmission of genomically distinct A. marginale strains predominates in high-prevalence areas of endemicity.
journal_name
Infect Immunjournal_title
Infection and immunityauthors
Vallejo Esquerra E,Herndon DR,Alpirez Mendoza F,Mosqueda J,Palmer GHdoi
10.1128/IAI.02537-14subject
Has Abstractpub_date
2014-12-01 00:00:00pages
5286-92issue
12eissn
0019-9567issn
1098-5522pii
IAI.02537-14journal_volume
82pub_type
杂志文章abstract::Natural-resistance-associated macrophage protein 1 (Nramp1) is a divalent cation transporter belonging to a family of transporter proteins highly conserved in eukaryotes and prokaryotes. Mammalian and bacterial transporters may compete for essential metal ions during mycobacterial infections. The mycobacterial Nramp h...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.70.8.4124-4131.2002
更新日期:2002-08-01 00:00:00
abstract::Thirty-two clinical isolates of Shiga-like toxin (SLT)-producing Escherichia coli associated with single cases or outbreaks of bloody diarrhea, hemorrhagic colitis, the hemolytic uremic syndrome, or edema disease of swine were examined for multiple copies of genes belonging to the slt-I or slt-II toxin families. Five ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.59.3.1065-1073.1991
更新日期:1991-03-01 00:00:00
abstract::Some clinical strains of Vibrio cholerae non-O1 produce an extracellular factor that evokes a rapid and dramatic cytotoxic response which manifests as cell rounding of Chinese hamster ovary (CHO) and HeLa cells without accompanying membrane damage. This study was performed to establish the identity of the non-membrane...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.64.8.3101-3108.1996
更新日期:1996-08-01 00:00:00
abstract::Little data are available regarding L-form phagocyte interactions. Due to difficulty with more conventional methods, a serum-free technique of surface phagocytosis employing cellulose ester micropore filters, fluorochrome staining, and reflecting fluorescence microscopy was developed. Intracellular localization of L-f...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.5.6.976-981.1972
更新日期:1972-06-01 00:00:00
abstract::The effect of iron concentration during growth on the physicochemical surface properties of the colonial variants of Neisseria gonorrhoeae has been assessed by aqueous two-phase partitioning in a dextran-polyethyleneglycol system containing positively charged trimethylamino-polyethyleneglycol or hydrophobic polyethyle...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.26.2.402-407.1979
更新日期:1979-11-01 00:00:00
abstract::The role of the spleen in hepatic amoebiasis in hamsters was studied. In hamsters receiving an intrahepatic inoculation of 10(5) trophozoites of axenic Entamoeba histolytica at 7 or 14 days postsplenectomy, the mean weight of metastatic foci increased significantly when compared with sham-splenectomized or intact cont...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.31.2.571-573.1981
更新日期:1981-02-01 00:00:00
abstract::The antiinflammatory cytokine response during urosepsis was determined by measurement of concentrations of soluble tumor necrosis factor receptor (sTNFR) types I and II, interleukin 1 receptor antagonist (IL-1ra), soluble IL-1 receptor type II (sIL-1RII), and interleukin 10 in sera and urine of 30 patients with cultur...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.66.8.3527-3534.1998
更新日期:1998-08-01 00:00:00
abstract::An inhibitory factor from Actinobacillus actinomycetemcomitans Y4 was isolated, and its properties indicated that it was a bacteriocin (actinobacillicin). The bacteriocin was active against Streptococcus sanguis strains, Streptococcus uberis (FDC1), and Actinomyces viscosus T14 as well as other strains of A. actinomyc...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.55.3.686-691.1987
更新日期:1987-03-01 00:00:00
abstract::Numerous studies have reported that asialo-GM(1), gangliotetraosylceramide, or moieties serve as epithelial cell receptors for Pseudomonas aeruginosa. Usually this interaction is confirmed with antibodies to asialo-GM(1). However, few, if any, of these reports have evaluated the binding of fresh clinical isolates of P...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.69.2.719-729.2001
更新日期:2001-02-01 00:00:00
abstract::Immune and pathologic responses were measured for 20 weeks after infection of mice with Brucella abortus 19, RB51, or 2308. Live bacteria and bacterial antigens of 19 and RB51 persisted in spleens for 10 and 4 weeks after infection, respectively, whereas 2308 bacteria and bacterial antigens persisted for at least 20 w...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.62.8.3206-3212.1994
更新日期:1994-08-01 00:00:00
abstract::We have demonstrated that possession of the gene for thermostable direct hemolysin-related hemolysin (trh) coincides with the presence of the urease gene among clinical Vibrio parahaemolyticus strains and that the location of the two genes are in close proximity on the chromosome. Here, we cloned and sequenced the 15,...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.68.10.5742-5748.2000
更新日期:2000-10-01 00:00:00
abstract::Immunoglobulin class-specific antibodies were measured by a solid-phase radioimmunoassay in serum, bronchoalveolar washings (BAW), lung cell lysates, and spleen cell lysates in germfree mice after intranasal (i.n.) and intraperitoneal (i.p.) primary and secondary 10(5), 10(4), and 10(3) mean tissue culture infective d...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.17.3.521-527.1977
更新日期:1977-09-01 00:00:00
abstract::Haemophilus ducreyi previously has been shown to inhibit the phagocytosis of both secondary targets and itself by certain cells in vitro. Wild-type H. ducreyi strain 35000HP contains two genes, lspA1 and lspA2, whose encoded protein products are predicted to be 456 and 543 kDa, respectively. An isogenic mutant of H. d...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.71.10.5994-6003.2003
更新日期:2003-10-01 00:00:00
abstract::Shigella flexneri is a gram-negative bacterium that causes bacillary dysentery in humans that is characterized by an acute inflammatory response of the colon. The fate of phagocytes that are infected in vitro with virulent Shigella has been the subject of some investigation and debate. In this study we found that viru...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.73.1.504-513.2005
更新日期:2005-01-01 00:00:00
abstract::Cholera enterotoxin and the related heat-labile enterotoxins of Escherichia coli enter their target cells through noncoated vesicles, but how the toxins are processed intracellularly and how they get to their targeted enzyme, adenylate cyclase, remain to be defined. Brefeldin A, an inhibitor of the trans-Golgi network...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.61.8.3282-3286.1993
更新日期:1993-08-01 00:00:00
abstract::In Vibrio cholerae, the transmembrane DNA binding proteins, ToxR and TcpP, activate expression of the regulatory gene toxT in response to specific environmental signals. The resulting enhanced level of ToxT leads to a coordinated increase in the production of a subset of virulence factors, including cholera toxin (CT)...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.72.7.3961-3967.2004
更新日期:2004-07-01 00:00:00
abstract::Respiratory epithelial cells play an active part in the host response to respiratory pathogens, such as Streptococcus pneumoniae, by releasing chemokines responsible for neutrophil recruitment. In order to investigate the role of specific pneumococcal virulence factors in eliciting CXC chemokine responses, type II pne...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.00954-06
更新日期:2006-12-01 00:00:00
abstract::The study of how bacteria respond to and obtain divalent metal ions provides insight into the regulation of virulence factors in the host environment. Regulation of metal permease operons in gram-positive bacteria may involve the binding of metal-responsive repressors to palindromic domains in their control regions. T...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.70.10.5706-5714.2002
更新日期:2002-10-01 00:00:00
abstract::Stenotrophomonas maltophilia is a ubiquitous bacterium and an emerging nosocomial pathogen. This bacterium is resistant to many antibiotics, associated with a number of infections, and a significant health risk, especially for immunocompromised patients. Given that Caenorhabditis elegans shares many conserved genetic ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.00711-15
更新日期:2015-12-07 00:00:00
abstract::T cell-independent antibody responses develop rapidly, within 3 to 4 days, and are critical for preventing blood-borne pathogens from evolving into life-threatening infections. The interaction of BAFF, also known as BLyS, with its receptors BAFFR and TACI on B cells is critical for B cell homeostasis and function. Usi...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.01147-13
更新日期:2014-01-01 00:00:00
abstract::Haemophilus ducreyi expresses 2 OmpA homologs, designated MOMP and OmpA2, whose genes are arranged in tandem on the chromosome. Northern blot analysis indicated that momp and ompA2 are transcribed independently. Sequences of the momp open reading frame (ORF) lacking the transcriptional start site were amplified by PCR...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.68.5.2602-2607.2000
更新日期:2000-05-01 00:00:00
abstract::We have identified a Crp/Fnr-like transcriptional regulator of Streptococcus pyogenes that when inactivated attenuates virulence. The gene, named srv for streptococcal regulator of virulence, encodes a 240-amino-acid protein with 53% amino acid similarity to PrfA, a transcriptional activator of virulence in Listeria m...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.72.3.1799-1803.2004
更新日期:2004-03-01 00:00:00
abstract::The innate and the adaptive arms of the mucosal immune system must be coordinated to facilitate the control of pathogenic invasion while maintaining immune homeostasis. Toll-like receptors, able to activate the cell to produce bactericidal and inflammatory cytokines but also able to upregulate antigen (Ag)-presenting ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.00100-07
更新日期:2008-02-01 00:00:00
abstract::To determine whether an ongoing response to Leishmania major would affect the response to a non-cross-reacting, non-leishmanial antigen, susceptible BALB/c mice and resistant C3H mice were infected with L. major parasites expressing Escherichia coli beta-galactosidase (beta-GAL); this parasite was designated L. major-...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.68.2.809-814.2000
更新日期:2000-02-01 00:00:00
abstract::Impaired erythropoiesis causes anemia during genetic disorders, chronic disease, and infection. In studies of the underlying mechanisms researchers have increasingly focused on gamma interferon (IFN-gamma). Here, we identified a previously unrecognized role for interleukin-15 (IL-15) in red blood cell homeostasis and ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.01836-06
更新日期:2007-05-01 00:00:00
abstract::The two-component regulatory system, GraRS, appears to be involved in staphylococcal responses to cationic antimicrobial peptides (CAPs). However, the mechanism(s) by which GraRS is induced, regulated, and modulated remain undefined. In this study, we used two well-characterized MRSA strains (Mu50 and COL) and their r...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.05669-11
更新日期:2012-01-01 00:00:00
abstract::Porphyromonas gingivalis, a gram-negative anaerobic bacterium associated with active lesions of chronic periodontitis, produces several proteinases which are presumably involved in host colonization, perturbation of the immune system, and tissue destruction. The aims of this study were to investigate the degradation o...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.72.8.4351-4356.2004
更新日期:2004-08-01 00:00:00
abstract::The gene encoding Clostridium sordellii phospholipase C (Csp) was cloned and expressed as a histidine-tagged (His-tag) protein, and the protein was purified to compare its enzymatic and biological activities with those of Clostridium perfringens phospholipase C (Cpa) and Clostridium bifermentans phospholipase C (Cbp)....
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.71.2.641-646.2003
更新日期:2003-02-01 00:00:00
abstract::The macrophage migration inhibition test was applied to the study of delayed hypersensitivity in mice vaccinated intravenously with oil-treated cell walls of Mycobacterium bovis BCG. Migration inhibition of peritoneal exudate cells from sensitized mice was demonstrated directly upon incubation of the cells with purifi...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.1.6.587-594.1970
更新日期:1970-06-01 00:00:00
abstract::Macrophages are among the most sensitive targets of bacterial endotoxin (LPS), responding to minute amounts of LPS by releasing a battery of inflammatory mediators. Transfection of macrophages with secretory leukocyte protease inhibitor (SLPI) renders these cells refractory to LPS stimulation. Here we show that uptake...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.67.9.4485-4489.1999
更新日期:1999-09-01 00:00:00