Prevalence of internalisation-associated gene, prtF1, among persisting group-A streptococcus strains isolated from asymptomatic carriers

Neeman, Revital; Keller, Natan; Barzilai, Asher; Korenman, Zinaida; Sela, Shlomo

doi:10.1016/s0140-6736(97)12452-7

Cited by 133 publications

(116 citation statements)

References 22 publications

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“…Specific virulence determinants that are required by strains to cause invasive diseases are unknown. Given that group A streptococcus may contain up to four genes encoding FBP's (sfbI, sfbII, prtFII and fbp54 ) and that SfbI has been shown to be preferentially associated with persistent cases of infection in one study [16], the carriage of FBP genes by group A streptococcus isolates from non-invasive and invasive diseases was determined. Since these S. pyogenes isolates belong to distinct vir types, they are epidemiologically unrelated isolates.…”

Section: Resultsmentioning

confidence: 99%

“…The differences in the repertoire of FBPs may reflect the propensity of the strains to colonize different tissues and thereby cause different patterns of diseases. To this end, a recent study [16] reported a high prevalence (92 %) of sfbI among the persisting S. pyogenes strains from the throats of patients with asymptomatic carriage after antibiotic therapy. This observation suggests that SfbI mediated internalization may be responsible for persistence in that population.…”

Section: Introductionmentioning

confidence: 99%

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Streptococcus pyogenes prtFII, but not sfbI, sfbII or fbp54, is represented more frequently among invasive-disease isolates of tropical Australia

et al. 2002

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Streptococcus pyogenes (group A streptococcus) strains may express several distinct ®bronectinbinding proteins (FBPs) which are considered as major streptococcal adhesins. Of the FBPs, SfbI was shown in Šitro to promote internalization of the bacterium into host cells and has been implicated in persistence. In the tropical Northern Territory, where group A streptococcal infection is common, multiple genotypes of the organism were found among isolates from invasive disease cases and no dominant strains were observed. To determine whether any FBPs is associated with invasive disease propensity of S. pyogenes, we have screened streptococcal isolates from bacteraemic and necrotizing fasciitis patients and isolates from uncomplicated infections for genetic endowment of 4 FBPs. No difference was observed in the distribution of sfbII, fbp54 and sfbI between the blood isolates and isolates from uncomplicated infection. We conclude that the presence of sfbI does not appear to promote invasive diseases, despite its association with persistence. We also show a higher proportion of group A streptococcus strains isolated from invasive disease cases possess prtFII when compared to strains isolated from non-invasive disease cases. We suggest that S. pyogenes may recruit different FBPs for different purposes. Keywords CMMB SUMMARYStreptococcus pyogenes (group A streptococcus) strains may express several distinct fibronectinbinding proteins (FBPs) which are considered as major streptococcal adhesins. Of the FBPs, SfbI was shown in itro to promote internalization of the bacterium into host cells and has been implicated in persistence. In the tropical Northern Territory, where group A streptococcal infection is common, multiple genotypes of the organism were found among isolates from invasive disease cases and no dominant strains were observed. To determine whether any FBPs is associated with invasive disease propensity of S. pyogenes, we have screened streptococcal isolates from bacteraemic and necrotizing fasciitis patients and isolates from uncomplicated infections for genetic endowment of 4 FBPs. No difference was observed in the distribution of sfbII, fbp54 and sfbI between the blood isolates and isolates from uncomplicated infection. We conclude that the presence of sfbI does not appear to promote invasive diseases, despite its association with persistence. We also show a higher proportion of group A streptococcus strains isolated from invasive disease cases possess prtFII when compared to strains isolated from non-invasive disease cases. We suggest that S. pyogenes may recruit different FBPs for different purposes.

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Section: Resultsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Streptococcus pyogenes prtFII, but not sfbI, sfbII or fbp54, is represented more frequently among invasive-disease isolates of tropical Australia

et al. 2002

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“…GAS strain SP3832 is an M12 serotype that was originally isolated from a carrier who continued to carry GAS in his throat following antibiotic therapy (Neeman et al, 1998). GAS was grown in Todd-Hewitt broth supplemented with 0 .…”

Section: Methodsmentioning

confidence: 99%

“…Furthermore, when an infected monolayer, incubated for 7 days with antibiotic-containing medium, was washed and incubated with fresh antibiotic-free medium, bacteria reappeared in the fluid, which suggested that GAS is capable of cell externalization (Ö sterlund & Engstrand, 1995). It was hypothesized that an increased internalization rate and prolonged intracellular survival are associated with persistent GAS carriage and recurrent infections (Ö sterlund & Engstrand, 1995;Neeman et al, 1998;Sela & Barzilai, 1999;Sela et al, 2000). Although the antibiotic-protection assay seems to be a valuable test for measuring internalization, it might suffer from limitations in the study of intracellular survival during long periods following internalization.…”

Section: Introductionmentioning

confidence: 99%

Fate of Streptococcus pyogenes and epithelial cells following internalization

Marouni

Sela

2004

Journal of Medical Microbiology

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The fate of GAS and epithelial cells following internalization was determined in this study. HEp-2 cells harbouring intracellular bacteria were treated with antibiotics to kill extracellular adherent bacteria, washed, and the fate of bacteria and epithelial cells was assessed up to 24 h post-infection. In the absence of antibiotics, massive bacterial growth was apparent in the cell medium, accompanied by extensive cell death, suggesting that intracellular bacteria had multiplied and damaged the monolayer. Addition of the internalization inhibitor, cytochalasin D, either pre-or post-internalization prevented bacterial growth and cell injury; post-internalization treatment with chloramphenicol had the same effect. Analysis of three apoptotic markers in HEp-2 cells -chromatin condensation, DNA laddering and translocation of phosphatidylserine onto the cell-surface membrane -indicated that HEp-2 cells underwent apoptosis. Taken together, the data presented here support a model in which intenalized bacteria can induce their own externalization into the medium by a process that requires both an intact host-cell cytoskeleton and de novo synthesis of bacterial proteins. Concomitantly, intracellular and, apparently, extracellular free bacteria induce apoptosis through their cytotoxic activity, and release essential nutrients required for their growth.

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“…Riteniamo pertanto opportuno ricorrere all'impiego di amoxicillina/acido clavulanico o ampicillina/sulbactam, piuttosto che di sola amoxicillina o ampicillina, a fronte della dimostrata sensibilità in vitro di quest'ultime. Inoltre, studi recenti hanno dimostrato che S. pyogenes, solitamente considerato un patogeno extracellulare, può internalizzare nell'epiteliocita faringeo, divenendo inattaccabile dalle molecole beta-lattamiche (8). Similmente, alla luce dei due casi clinici descritti, noi ipotizziamo che S. dysgalactiae subsp.…”

Section: Conclusioni E Discussioneunclassified

Streptococcus dysgalactiae subsp. equisimilis: two cases of tonsillitis

Savini¹,

Giuseppe²,

Manna³

et al. 2008

Microbiol Med

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INTRODUZIONES. dysgalactiae subsp. equisimilis appartiene al gruppo C o G di Lancefield ed è responsabile di rare epidemie di faringotonsillite nelle popolazioni adulta e pediatrica (1); è invece considerato un agente eziologico inusuale di episodi tonsillitici acuti a carattere sporadico (2). Sono documentati tra l'altro episodi di setticemia, endocardite, polmonite, meningite, sostenuti da S. dysgalactiae subsp. equisimilis, che non è pertanto agente eziologico di sole infezioni dell'alto tratto respiratorio (1, 2). Le infezioni faringotonsillari da streptococchi dei gruppi C e G di Lancefield sono talora responsabili di incremento del titolo antistreptolisinico e dello sviluppo di sequele non suppurative, in particolare glomerulonefrite ed artrite reattiva (6, 7), similmente a quanto ormai noto a proposito delle infezioni da S. pyogenes. Diversamente, gli streptococchi del gruppo B non sono mai stati associati a complicanze non suppurative; tuttavia sono descritte, in corso di infezioni faringotonsillari da S. agalactiae, beta-emolitico del gruppo B, localizzazioni silenti o sintomatiche del medesimo stipite a livello cutaneo o genitourinario (2). Come descritto da altri autori riguardo alle infezioni da S. pyogenes, noi riteniamo che una eradicazione faringotonsillare subtotale di S. dysgalactiae subsp. equisimilis possa determinare l'insorgenza di recidive e/o di persistente colonizzazione tonsillare e faringea, condizione, quest'ultima, sfavorevole per la comunità, oltre che il paziente stesso. TassonomiaSu terreni al sangue, gli streptococchi beta-emolitici formano tipiche small colonies (Streptococcus anginosus group) o large colonies (Streptococcus pyogenes, gruppo A; Streptococcus equi subsp. zooepidemicus, group C; Streptococcus dysgalactiae subsp. equisimilis, gruppo C o G). Per quanto S. pyogenes e S. dysgalactiae siano solitamente considerati streptococchi beta-emolitici, è nota l'esistenza di varianti non-emolitiche (4). Stipiti non-emolitici di S. pyogenes sono stati isolati sia da tonsille di portatori sani quanto da casi di faringotonsillite acuta. In particolare, è stata descritta un'epidemia di faringotonsillite SUMMARYWe described two case reports of S. dysgalactiae subsp. equisimilis tonsillitis occurred from January 2005 to January 2007, among patients who come to our observation during these two years. These patients are paradigmatic of some conditions: adult age, absence of underlying diseases, outbreak of similar pharyngo-tonsillar sympyomatology, unsuccessful oral penicillin therapy, isolation of S. dysgalactiae subsp. equisimilis from throat swab, complete recovery after oral beta-lattamic antibiotic therapy, but total clearance of the microorganism only after oral macrolides administrations. Thus, the intracellular localization of S. dysgalactiae subsp. equismilis, could be in charge of the failure of beta-lattamic antibiotics therapy.

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Prevalence of internalisation-associated gene, prtF1, among persisting group-A streptococcus strains isolated from asymptomatic carriers

Cited by 133 publications

References 22 publications

Streptococcus pyogenes prtFII, but not sfbI, sfbII or fbp54, is represented more frequently among invasive-disease isolates of tropical Australia

Streptococcus pyogenes prtFII, but not sfbI, sfbII or fbp54, is represented more frequently among invasive-disease isolates of tropical Australia

Fate of Streptococcus pyogenes and epithelial cells following internalization

Streptococcus dysgalactiae subsp. equisimilis: two cases of tonsillitis

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