Dataset Information

Carbapenem-resistant Klebsiella pneumoniae exhibit variability in capsular polysaccharide and capsule associated virulence traits.

ABSTRACT:

Background

Novel therapies are urgently needed to treat carbapenem-resistant Klebsiella pneumoniae (CR-Kp)-mediated infection, which constitute a major health threat in the United States. In order to assess if it is feasible to develop anticapsular antibodies as a potential novel therapy, it is crucial to first systematically characterize capsular polysaccharide (CPS) and virulence traits in these strains.

Methods

Forty CR-Kp were genotyped by pulsed field gel electrophoresis, multilocus sequence typing (MLST), and molecular capsule typing (C-patterns and wzi sequencing). Their biofilm formation, serum resistance, macrophage-mediated killing, and virulence in Galleria mellonella were compared. MAb (1C9) was generated by co-immunization with 2 CPSs, and cross-reactivity was investigated.

Results

MLST assigned 80% of CR-Kp isolates to the ST258-clone. Molecular capsule typing identified new C-patterns, including C200/wzi-154, which was widely represented and associated with blaKPC-3-bearing strains. Heterogeneity was detected in biofilm formation and macrophage-mediated killing. Differences in serum resistance correlated with virulence in G. mellonella. ST258 strains carrying blaKPC-3 were less virulent than those with blaKPC-2. MAb 1C9 cross-reacted with 58% of CR-Kp CPSs.

Conclusions

CR-Kp ST258 strains exhibit variability of virulence-associated traits. Differences were associated with the type of KPC gene and CPS. Identification of cross-reacting anti-CPS mAbs encourages their development as adjunctive therapy.

SUBMITTER: Diago-Navarro E

PROVIDER: S-EPMC4432395 | biostudies-literature | 2014 Sep

REPOSITORIES: biostudies-literature

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Publications

Carbapenem-resistant Klebsiella pneumoniae exhibit variability in capsular polysaccharide and capsule associated virulence traits.

Diago-Navarro Elizabeth E Chen Liang L Passet Virginie V Burack Seth S Ulacia-Hernando Amaia A Kodiyanplakkal Rosy Priya RP Levi Michael H MH Brisse Sylvain S Kreiswirth Barry N BN Fries Bettina C BC

The Journal of infectious diseases 20140314 5

<h4>Background</h4>Novel therapies are urgently needed to treat carbapenem-resistant Klebsiella pneumoniae (CR-Kp)-mediated infection, which constitute a major health threat in the United States. In order to assess if it is feasible to develop anticapsular antibodies as a potential novel therapy, it is crucial to first systematically characterize capsular polysaccharide (CPS) and virulence traits in these strains.<h4>Methods</h4>Forty CR-Kp were genotyped by pulsed field gel electrophoresis, mul ...[more]

PMID: 24634498

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Dataset Information

Carbapenem-resistant Klebsiella pneumoniae exhibit variability in capsular polysaccharide and capsule associated virulence traits.

Background

Methods

Results

Conclusions

Publications

Carbapenem-resistant Klebsiella pneumoniae exhibit variability in capsular polysaccharide and capsule associated virulence traits.

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