Autor: |
Sabrina Nicolò, Giorgio Mattiuz, Alberto Antonelli, Fabio Arena, Vincenzo Di Pilato, Tommaso Giani, Ilaria Baccani, Ann Maria Clemente, Giuseppe Castronovo, Michele Tanturli, Federico Cozzolino, Gian Maria Rossolini, Maria Gabriella Torcia |
Jazyk: |
angličtina |
Rok vydání: |
2022 |
Předmět: |
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Zdroj: |
Microorganisms, Vol 10, Iss 2, p 384 (2022) |
Druh dokumentu: |
article |
ISSN: |
2076-2607 |
DOI: |
10.3390/microorganisms10020384 |
Popis: |
Hypervirulent Klebsiella pneumoniae (Hv-Kp) strains have emerged as pathogens causing life-threatening, invasive disease even in immunocompetent hosts. Systemic dissemination usually occurs following perturbations of the gut microbiota and is facilitated by Hv-Kp resistance to phagocytosis and complement activity. Hv-Kp are usually associated with K1 or K2 capsular types, produce several iron uptake systems (e.g., aerobactin and salmochelin) and are often but not invariably, capsular material hyper-producers (hypermucoviscous phenotype: HMV). Whether Hv-Kp escape the immune response at mucosal site is unknown. In this work, we studied the effects of Hv-Kp on human dendritic cells (DCs), central players of the IL-23/IL-17 and IL-12/IFN-γ axis at mucosal sites, essential for pathogen clearance. Four Hv-Kp and HMV strains were selected and their activity on DC maturation and cytokine production was compared to that of non-virulent Kp strains with classic or HMV phenotypes. While the maturation process was equally induced by all Kp strains, significant differences between virulent and non-virulent strains were found in the expression of genes for cytokines involved in T-cell activation and differentiation. The non-virulent KP04C62 and the classic Kp, KPC157 induced high expression of TH1 (IL-12p70 and TNFα) and TH17 cytokines (IL-23, IL-1β and IL-6), while Hv-Kp poorly activated these cytokine genes. Moreover, conditioned media from DCs cultured with non-virulent Kp, either classical or hypercapsulated, induced the activation of IL-17 and IFN-γ genes in preactivated CD4+-cells suggesting their TH17/TH1 differentiation. Conditioned media from Hv-Kp poorly activated IL-17 and IFN-γ genes. In summary, our data indicate that Hv-Kp interfere with DC functions and T-cell differentiation and suggest that the escape from the IL-23/IL-17 and IL-12/IFN-γ axes may contribute to pathogen dissemination in immunocompetent hosts. |
Databáze: |
Directory of Open Access Journals |
Externí odkaz: |
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