CYTOSKELETON DYSREGULATION: A MECHANISM OF NEUTROPHIL EVASION BY KLEBSIELLA PNEUMONIAE ST258?

BIRNBERG WEISS F; PITTALUGA, JOSÉ R.; CASTRO, J; MARTIRE GRECO D; LEDESMA M; GOMEZ S.A.; LANDONI V.I; FERNÁNDEZ G.C.

San Luis

Congreso; LXXI REUNIÓN CIENTÍFICA ANUAL DE LA SOCIEDAD ARGENTINA DE INMUNOLOGÍA (SAI); 2023

The cytoskeleton plays a key role in different neutrophil (PMN) functions, such as migration, phagocytosis, the assembly of NADPH oxidase and ROS production, degranulation and NETs formation. We have previously demonstrated that Klebsiella pneumoniae ST258 (Kp) is capable of inhibiting neutrophil microbicidal responses, such as ROS production, azurophilic granule mobilization, and NETs release. To understand the mechanism behind this phenomenon, our aim was to assess the impact of Kp on the PMN cytoskeleton. To evaluate actin cytoskeleton dynamics, we used phalloidin to perform kinetics studies on isolated human PMN by flow cytometry, in the presence of Kp or Escherichia coli (Eco), a potent inducer of PMN responses. While Kp did not show differences compared to untreated neutrophils, Eco induced a sustained gradual increase in the levels of actin polymerization from one hour post-incubation (p