Klebsiella capsular type versus site of isolation.

Riser, Eve; Noone, Paul

doi:10.1136/jcp.34.5.552

Cited by 26 publications

(19 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The ability of MrkDpossessing fimbriae to grow on the underlying matrix of epithelial cells cultured in vitro strongly suggests that disruption of an intact epithelial surface is necessary for type 3 fimbriate bacteria to grow on host surfaces. This is consistent with the clinical observations associated with nosocomially acquired infections due to K. pneumoniae (Craven et al, 1990;Duma, 1985;Riser & Noone, 1981).…”

Section: Strainsupporting

confidence: 90%

Klebsiella pneumoniae MrkD-mediated biofilm formation on extracellular matrix- and collagen-coated surfaces

2003

View full text Add to dashboard Cite

The type 3 fimbriae of Klebsiella pneumoniae are comprised of the major fimbrial subunit (MrkA) and the adhesin (MrkD) that has previously been shown to mediate binding to collagen. The ability of adhesive and non-adhesive derivatives of K. pneumoniae to form biofilms on collagen-coated surfaces in continuous-flow chambers was investigated. Unlike biofilm formation on abiotic plastic surfaces, the presence of the MrkD adhesin was necessary for growth on collagen-coated surfaces. Fimbriate strains lacking the MrkD adhesin did not efficiently adhere to and grow on these surfaces. Similarly, purified human extracellular matrix and the extracellular matrix formed by human bronchial epithelial cells grown in vitro provided a suitable substrate for MrkD-mediated biofilm formation, whereas direct binding to the respiratory cells was not observed. Type 3 fimbriae may therefore have two roles in the early stages of adherence and growth on in-dwelling devices such as endotracheal tubes. The MrkA polypeptide could facilitate adsorption to abiotic polymers of recently implanted devices and the MrkD adhesin could enable bacteria to adhere to and grow on polymers coated with host-derived proteins.

show abstract

Section: Strainsupporting

confidence: 90%

Klebsiella pneumoniae MrkD-mediated biofilm formation on extracellular matrix- and collagen-coated surfaces

2003

View full text Add to dashboard Cite

show abstract

“…Although much attention has been paid to the relationship between serotype or biotype or both and the site of isolation (Orskov, 1955;Eickhoff et al, 1966;Steinhauer et al, 1966;Riser and Noone, 1981;Smith et al, 1982), few studies are known in which the virulence of Klebsiella strains is compared. The use of an intraperitoneal mouse virulence test by Foster and Bragg (1962) to distinguish Friedlander's bacillus from the non pathogenic K .…”

Section: Discussionmentioning

confidence: 99%

Virulence of Klebsiella strains in experimentally induced skin lesions in the mouse

Simoons-Smit¹,

Vught²,

Kanis³

et al. 1984

Journal of Medical Microbiology

View full text Add to dashboard Cite

SUMMARY. The virulence of 93 clinical isolates of Klebsiella was compared in a mouse model by subcutaneous injection. Skin pathogenicity was measured by estimating the number of viable bacteria in the lesions 24 h after infection with a dose of lo7 bacteria. Strains of serotypes K 1-6 were compared with strains of serotypes higher than K6. All K 1 and K5, and some K2 and K4 strains were more virulent for mice than strains with a serotype higher than K6. The K3 strains were significantly less virulent than the strains with a serotype higher than K6. The bacteriological findings were confirmed by histological examination with some strains. No differences in virulence were observed between strains of the same serotype isolated from patients with cystitis or from those with pyelonephritis, nor between strains of the same serotype isolated from the blood of patients with septicaemia or from other sites. The mouse model has been found satisfactory for observing differences in virulence between Klebsiella isolates.

show abstract

“…A polysaccharide-based vaccine has been tested (5). Based on the structural variability of its capsular polysaccharides (CPS), Klebsiella has been classified into 77 serotypes (27), which differ markedly in pathogenicity potential and epidemiological relevance (3,28,29,35). Epidemiological findings showed that over 70% of all cases of Klebsiella bacteremia were caused by only 25 of the 77 different serotypes (6).…”

mentioning

confidence: 99%

Capsule Impedes Adhesion to and Invasion of Epithelial Cells by Klebsiella pneumoniae

Podschun²,

et al. 2000

View full text Add to dashboard Cite

The adhesion of K21a, K26, K36, and K50 capsulated Klebsiella strains to ileocecal (HCT-8) and bladder (T24) epithelial cell lines was significantly lower than that of their corresponding spontaneous noncapsulated variants K21a/3, K26/1, K36/3, and K50/3, respectively. Internalization of the bacteria by both epithelial cell lines was also significantly reduced. Similarly, a capsule-switched derivative, K2(K36), that exhibited a morphologically larger K36 capsule and formed more capsular material invaded the ileocecal epithelial cell line poorly compared to the corresponding K2 parent strain. None of the capsulated strains exhibited significant mannose-sensitive type 1 fimbriae, whereas two of the noncapsulated variants K21a/3 and K50/3 exhibited potent mannose-sensitive hemagglutinating activity. Although hemagglutinating activity that could be attributed to mannose-resistant Klebsiella type 3 fimbriae was weak in all strains, in several cases the encapsulated parent strains exhibited lower titers than their corresponding noncapsulated variants. Although the level of adhesion to the ileocecal cells is not different from adhesion to bladder cells, bacterial internalization by bladder cells was significantly lower than internalization by ileocecal cells, suggesting that bladder cells lack components required for the internalization of Klebsiella.Klebsiella pneumoniae is an opportunistic pathogen involved in outbreaks of nosocomial infections, such as bacteremia and sepsis, mainly in immunocompromised individuals (36). Due to the emergence of multidrug resistance among Klebsiella strains, the search for new approaches for the prevention or treatment of Klebsiella infections is now under intensive investigation (34). To be successful, these efforts will require a better understanding of the infectious process.Multiple Klebsiella components (e.g., fimbriae, siderophores, O antigens, and capsular antigens) have been considered to be potential virulence factors (34). Of these factors, capsular antigens are probably considered the major determinants of pathogenicity (4,9,17,21). As a consequence, new therapeutic approaches have been targeted against the capsule. A polysaccharide-based vaccine has been tested (5). Based on the structural variability of its capsular polysaccharides (CPS), Klebsiella has been classified into 77 serotypes (27), which differ markedly in pathogenicity potential and epidemiological relevance (3,28,29,35). Epidemiological findings showed that over 70% of all cases of Klebsiella bacteremia were caused by only 25 of the 77 different serotypes (6).

show abstract

Klebsiella capsular type versus site of isolation.

Cited by 26 publications

References 9 publications

Klebsiella pneumoniae MrkD-mediated biofilm formation on extracellular matrix- and collagen-coated surfaces

Klebsiella pneumoniae MrkD-mediated biofilm formation on extracellular matrix- and collagen-coated surfaces

Virulence of Klebsiella strains in experimentally induced skin lesions in the mouse

Capsule Impedes Adhesion to and Invasion of Epithelial Cells by Klebsiella pneumoniae

Contact Info

Product

Resources

About