Pathogenesis of Klebsiella Pneumoniae Induced Proteinopathy is Amyloid Strain Dependent

Abstract Introduction/Objective The World Health Organization has labeled Klebsiella pneumoniae (KP), a Gram-negative bacterium, as a ‘Critical Priority’ pathogen due to its increasing prevalence in serious conditions like pneumonia and sepsis, along with its growing resistance to multiple drugs. Infections with KP have been linked to the collapse of microtubules and the release of harmful proteins called amyloid-beta (Aβ) and tau from lung endothelial cells. These infection-induced lung endothelial amyloids can spread like prions and are stable under heat. Methods/Case Report However, the mechanisms behind these effects and whether the infection-generated proteinopathy depends on tau and/or Aβ were not well understood. This study hypothesized that KP infection triggers tau dysfunction, breakdown of microtubules, increased lung barrier permeability, and the production and release of toxic amyloids. To test this, researchers used CRISPR/Cas9 technology to create lung endothelial cells without tau and/or amyloid precursor protein (APP). They confirmed gene deletion through various methods and exposed these cells, along with regular cells, to a highly virulent KP strain. Results (if a Case Study enter NA) The results showed that the KP strain (Kp 1-008) caused disruption of cellular structures, increased permeability, and bacterial spread within hours of infection. Supernatants containing proteins from infected cells, when applied to healthy cells, led to barrier disruption, permeability, and cell death. Interestingly, different pathologies were induced by supernatants from cells lacking tau or APP, indicating that either tau or Aβ alone could propagate damage in a strain- specific manner. The most severe damage required both tau and Aβ together. Conclusion In conclusion, KP infection disturbs cellular structures, promoting barrier breakdown and bacterial dissemination. It also generates toxic tau and Aβ proteins. Either of these proteins can spread harm from cell to cell, but together, they enhance the severity and potency of the resulting lung endothelial protein damage caused by the infection. The study sheds light on the complex mechanisms of KP-related infections and their impact on cellular structures and protein pathways.