A hexasaccharide from capsular polysaccharide of carbapenem-resistant Klebsiella pneumoniae KN2 is a ligand of Toll-like receptor 4

Abstract Background The molecular characterization of carbapenem-resistant hypervirulent Klebsiella pneumoniae (CR-hvKP) isolates is not well studied. Our goal was to investigate the molecular epidemiology of CR-hvKP strains that were isolated from a Chinese hospital. Results All clinical carbapenem-resistant K. pneumoniae (CR-KP) isolates were collected and identified from patient samples between 2014 and 2017 from a Chinese hospital. The samples were subjected to screening for CR-hvKP by string test and the detection of the aerobactin gene. CR-hvKP isolates were further confirmed through neutrophil phagocytosis and a mice lethality assay. The CR-hvKP isolates were investigated for their capsular genotyping, virulence gene profiles, and the expression of carbapenemase genes by PCR and DNA sequencing. Multilocus sequence type (MLST) and pulsed-field gel electrophoresis (PFGE) were performed to exclude the homology of these isolates. Twenty strains were identified as CR-hvKP. These strains were resistant to imipenem and several other antibiotics, however, most were susceptible to amikacin. Notably, two isolates were not susceptible to tigecycline. Capsular polysaccharide synthesis genotyping revealed that 17 of the 20 CR-hvKP strains belonged to the K2 serotype, while the others belonged to serotypes other than K1, K2, K5, K20, and K57. The strains were found to be positive for 10 types of virulence genes and a variety of these genes coexisted in the same strain. Two carbapenemase genes were identified: blaKPC-2 (13/20) and blaNDM-1 (1/20). PFGE typing revealed eight clusters comprising isolates that belonged to MLST types ST25, ST11 and ST375, respectively. PFGE cluster A was identified as the main cluster, which included 11 isolates that belong to ST25 and mainly from ICU department. Conclusions Our findings suggest that hospital-acquired infections may contribute in part to the CR-hvKP strains identified in this study. It also suggests that ST25 CR-hvKP strain has a clonal distribution in our hospital. Therefore, effective surveillance and strict infection control strategies should be implemented to prevent outbreak by CR-hvKP strains in hospitals setting.

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Humoral Immunity against Capsule Polysaccharide Protects the Host from magA+Klebsiella pneumoniae-Induced Lethal Disease by Evading Toll-Like Receptor 4 Signaling

Infection and Immunity ◽

10.1128/iai.00931-08 ◽

2008 ◽

Vol 77 (2) ◽

pp. 615-621 ◽

Cited By ~ 26

Author(s):

Ming-Fang Wu ◽

Chih-Ya Yang ◽

Tzu-Lung Lin ◽

Jin-Town Wang ◽

Feng-Ling Yang ◽

...

Keyword(s):

Klebsiella Pneumoniae ◽

Liver Abscess ◽

Vaccine Development ◽

Pyogenic Liver Abscess ◽

Underlying Mechanism ◽

Toll Like Receptor ◽

Toll Like Receptor 4 ◽

Mortality And Morbidity ◽

Promising Target

ABSTRACT Klebsiella pneumoniae magA (for mucoviscosity-associated gene A) is linked to the pathogenesis of primary pyogenic liver abscess, but the underlying mechanism by which magA increases pathogenicity is not well elucidated. In this study, we investigated the role of the capsular polysaccharides (CPS) in the pathogenesis of magA + K. pneumoniae by comparing host immunity to magA + K. pneumoniae and a ΔmagA mutant. We found that Toll-like receptor 4 recognition by magA + K. pneumoniae was hampered by the mucoviscosity of the magA + K. pneumoniae CPS. Interestingly, monoclonal antibodies (MAbs) against magA + K. pneumoniae CPS recognized all of the K1 strains tested but not the ΔmagA and non-K1 strains. Moreover, the anti-CPS MAbs protected mice from magA + K. pneumoniae-induced liver abscess formation and lethality. This indicates that the K1 epitope is a promising target for vaccine development, and anti-CPS MAbs has great potential to protect host from K1 strain-induced mortality and morbidity in diabetic and other immunocompromised patients in the future.

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Serum Antibody Responses against Carbapenem-Resistant Klebsiella pneumoniae in Infected Patients

mSphere ◽

10.1128/msphere.01335-20 ◽

2021 ◽

Vol 6 (2) ◽

Author(s):

Kasturi Banerjee ◽

Michael P. Motley ◽

Elizabeth Diago-Navarro ◽

Bettina C. Fries

Keyword(s):

Klebsiella Pneumoniae ◽

Capsular Polysaccharide ◽

Serum Antibody ◽

Antibody Responses ◽

Capsular Polysaccharides ◽

Content Type ◽

Carbapenem Resistant ◽

Reactive Properties

ABSTRACT Capsular polysaccharide (CPS) heterogeneity within carbapenem-resistant Klebsiella pneumoniae (CR-Kp) strain sequence type 258 (ST258) must be considered when developing CPS-based vaccines. Here, we sought to characterize CPS-specific antibody responses elicited by CR-Kp-infected patients. Plasma and bacterial isolates were collected from 33 hospital patients with positive CR-Kp cultures. Isolate capsules were typed by wzi sequencing. Reactivity and measures of efficacy of patient antibodies were studied against 3 prevalent CR-Kp CPS types (wzi29, wzi154, and wzi50). High IgG titers against wzi154 and wzi50 CPS were documented in 79% of infected patients. Patient-derived (PD) IgGs agglutinated CR-Kp and limited growth better than naive IgG and promoted phagocytosis of strains across the serotype isolated from their donors. Additionally, poly-IgG from wzi50 and wzi154 patients promoted phagocytosis of nonconcordant CR-Kp serotypes. Such effects were lost when poly-IgG was depleted of CPS-specific IgG. Additionally, mice infected with wzi50, wzi154, and wzi29 CR-Kp strains preopsonized with wzi50 patient-derived IgG exhibited lower lung CFU than controls. Depletion of wzi50 antibodies (Abs) reversed this effect in wzi50 and wzi154 infections, whereas wzi154 Ab depletion reduced poly-IgG efficacy against wzi29 CR-Kp. We are the first to report cross-reactive properties of CPS-specific Abs from CR-Kp patients through both in vitro and in vivo models. IMPORTANCE Carbapenem-resistant Klebsiella pneumoniae is a rapidly emerging public health threat that can cause fatal infections in up to 50% of affected patients. Due to its resistance to nearly all antimicrobials, development of alternate therapies like antibodies and vaccines is urgently needed. Capsular polysaccharides constitute important targets, as they are crucial for Klebsiella pneumoniae pathogenesis. Capsular polysaccharides are very diverse and, therefore, studying the host’s capsule-type specific antibodies is crucial to develop effective anti-CPS immunotherapies. In this study, we are the first to characterize humoral responses in infected patients against carbapenem-resistant Klebsiella pneumoniae expressing different wzi capsule types. This study is the first to report the efficacy of cross-reactive properties of CPS-specific Abs in both in vitro and in vivo models.

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Cutting Edge: Roles of Toll-Like Receptor 4 and IL-23 in IL-17 Expression in Response to Klebsiella pneumoniae Infection

The Journal of Immunology ◽

10.4049/jimmunol.170.9.4432 ◽

2003 ◽

Vol 170 (9) ◽

pp. 4432-4436 ◽

Cited By ~ 336

Author(s):

Kyle I. Happel ◽

Mingquan Zheng ◽

Erana Young ◽

Lee J. Quinton ◽

Euan Lockhart ◽

...

Keyword(s):

Klebsiella Pneumoniae ◽

Cutting Edge ◽

Toll Like Receptor ◽

Toll Like Receptor 4

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Differential Effects of Three Subtypes of Klebsiella Pneumoniae On the Expression of Toll-Like Receptor 4 in Alveolar Epithelial Type II Cells

SSRN Electronic Journal ◽

10.2139/ssrn.3946289 ◽

2021 ◽

Author(s):

Heming Wang ◽

Wei Tang ◽

Shanshan Wang ◽

Xiubing Hang ◽

Qiang Zhou ◽

...

Keyword(s):

Klebsiella Pneumoniae ◽

Type Ii Cells ◽

Type Ii ◽

Toll Like Receptor ◽

Toll Like Receptor 4 ◽

Differential Effects ◽

Alveolar Epithelial

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Carbapenem-Resistant Klebsiella pneumoniae Exhibit Variability in Capsular Polysaccharide and Capsule Associated Virulence Traits

The Journal of Infectious Diseases ◽

10.1093/infdis/jiu157 ◽

2014 ◽

Vol 210 (5) ◽

pp. 803-813 ◽

Cited By ~ 74

Author(s):

Elizabeth Diago-Navarro ◽

Liang Chen ◽

Virginie Passet ◽

Seth Burack ◽

Amaia Ulacia-Hernando ◽

...

Keyword(s):

Klebsiella Pneumoniae ◽

Capsular Polysaccharide ◽

Carbapenem Resistant ◽

Virulence Traits

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Identification of a Depolymerase Specific for K64-Serotype Klebsiella pneumoniae: Potential Applications in Capsular Typing and Treatment

Antibiotics ◽

10.3390/antibiotics10020144 ◽

2021 ◽

Vol 10 (2) ◽

pp. 144

Author(s):

Jiayin Li ◽

Yueying Sheng ◽

Ruijing Ma ◽

Mengsha Xu ◽

Fuli Liu ◽

...

Keyword(s):

Klebsiella Pneumoniae ◽

Capsular Polysaccharide ◽

Vaccine Development ◽

Preventive Intervention ◽

Global Public Health ◽

Carbapenem Resistant ◽

Potential Applications ◽

Typing Methods ◽

Therapeutic Biologics ◽

Capsular Typing

Carbapenem-resistant Klebsiella pneumoniae (CRKP), one of the major nosocomial pathogens, is increasingly becoming a serious threat to global public health. There is an urgent need to develop effective therapeutic and preventive approaches to combat the pathogen. Here, we identified and characterized a novel capsule depolymerase (K64-ORF41) derived from Klebsiella phage SH-KP152410, which showed specific activities for K. pneumoniae K64-serotype. We showed that this depolymerase could be used in the identification of K64 serotypes based on the capsular typing, and the results agreed well with those from the conventional serotyping method using antisera. From this study, we also identified K64 mutant strains, which showed typing discrepancy between wzi-sequencing based genotyping and depolymerase-based or antiserum-based typing methods. Further investigation indicated that the mutant strain has an insertion sequence (IS) in wcaJ, which led to the alteration of the capsular serotype structure. We further demonstrated that K64-ORF41 depolymerase could sensitize the bacteria to serum or neutrophil killing by degrading the capsular polysaccharide. In summary, the identified K64 depolymerase proves to be an accurate and reliable tool for capsular typing, which will facilitate the preventive intervention such as vaccine development. In addition, the polymerase may represent a potential and promising therapeutic biologics against CRKP-K64 infections.

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Population Structure of KPC-Producing Klebsiella pneumoniae Isolates from Midwestern U.S. Hospitals

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.00125-14 ◽

2014 ◽

Vol 58 (8) ◽

pp. 4961-4965 ◽

Cited By ~ 56

Author(s):

Meredith S. Wright ◽

Federico Perez ◽

Lauren Brinkac ◽

Michael R. Jacobs ◽

Keith Kaye ◽

...

Keyword(s):

Klebsiella Pneumoniae ◽

Capsular Polysaccharide ◽

Sequence Type ◽

Single Nucleotide Variants ◽

Single Nucleotide ◽

Content Type ◽

Strain Diversity ◽

Carbapenem Resistant ◽

Genetic Context ◽

Over Time

ABSTRACTGenome sequencing of carbapenem-resistantKlebsiella pneumoniaeisolates from regional U.S. hospitals was used to characterize strain diversity and theblaKPCgenetic context. A phylogeny based on core single-nucleotide variants (SNVs) supports a division of sequence type 258 (ST258) into two distinct groups. The primary differences between the groups are in the capsular polysaccharide locus (cps) and their plasmid contents. A strict association between clade and KPC variant was found. TheblaKPCgene was found on variants of two plasmid backbones. This study indicates that highly similarK. pneumoniaesubpopulations coexist within the same hospitals over time.

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Chemical synthesis of the hexasaccharide related to the repeating unit of the capsular polysaccharide from carbapenem resistant Klebsiella pneumoniae 2796 and 3264

RSC Advances ◽

10.1039/c6ra07351d ◽

2016 ◽

Vol 6 (46) ◽

pp. 40147-40154 ◽

Cited By ~ 6

Author(s):

Vikramjit Sarkar ◽

Balaram Mukhopadhyay

Keyword(s):

Klebsiella Pneumoniae ◽

Chemical Synthesis ◽

Total Synthesis ◽

Capsular Polysaccharide ◽

Carbapenem Resistant

Total synthesis of the hexasaccharide repeating unit of the capsular polysaccharide fromKlebsiella pneumoniae2796 and 3264 following a linear sequential glycosylation strategy.

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