The Roles of a Multidrug-Resistant <i>Klebsiella pneumoniae</i> High-Risk Clone and Its Resistance Plasmids on the Gastrointestinal Colonization and Host-Defense Effectors in the Gut

• Principais autores: Balazs Stercz (Autor), Judit Domokos (Autor), Zsuzsanna A. Dunai (Autor), Nora Makra (Autor), Janos Juhasz (Autor), Eszter Ostorhazi (Autor), Bela Kocsis (Autor), Dora Szabo (Autor)
• Formato: Livro
• Publicado em: MDPI AG, 2024-07-01T00:00:00Z.
• Assuntos: article
• Acesso em linha: Connect to this object online.

Resumo

The asymptomatic gastrointestinal colonization of multidrug-resistant (MDR) bacteria can lead to difficult-to-treat infections. We investigated the role of host factors influencing colonization in an orogastrical murine infection model using a CTX-M-15- and OXA-162-producing <i>Klebsiella pneumoniae</i> ST15 (MDR-KP) strain, as well as <i>Escherichia coli</i> J53 (EC) and <i>E. coli</i> transconjugants with an IncFII(K) plasmid carrying CTX-M-15 (EC-CTXM), and with an IncL plasmid carrying OXA-162 (EC-OXA) genes. The fecal bacterial count in colony-forming unit/gram stool (CFU/g) was determined by cultivation, IgA and defensin levels by ELISA, and gut microbiota by 16S rRNA analysis. The CFU was the lowest in EC, followed by EC-OXA and EC-CTXM, and the highest in the MDR-KP group. The IgA level in feces increased in MDR-KP, EC-CTXM, and EC-OXA, and did not change in EC. The beta-defensin 3 level markedly increased in all groups, with the highest values in MDR-KP and EC-CTXM. Alpha-defensin-5 increased in all groups especially in EC. In microbiota, the <i>Bacteroidota</i> phylum was dominant in MDR-KP, EC-CTXM, and EC-OXA, whereas <i>Proteobacteria</i> was dominant in EC. The <i>Muribaculaceae</i> family was significantly more common in the MDR-KP and EC-OXA groups, while the <i>Lachnospiraceae</i> family was dominant in the EC group. While fecal IgA levels positively correlated with colonizing bacterial CFU, the alpha-defensin 5 levels inversely correlated with CFUs and IgA levels. The presence of the IncFII(K) plasmid induced beta-defensin 3 production. The amounts of the <i>Muribaculaceae</i> family members exhibited a correlation with the IncL plasmid. The detected amounts of the <i>Lachnospiraceae</i> family indicated the protective role against the high-risk clone and the resistance plasmids' dissemination. Our results suggest that not only the MDR-KP clone itself but also the resistance plasmids play a primary role in the colonization rate in the gastrointestinal tract. Both the MDR-KP clone as well as the IncFII(K) and IncL resistance plasmids provide survival and colonization benefits in the gut.

Descrição do item

10.3390/antibiotics13080698
2079-6382