Vesicle-Mediated Dendritic Cell Activation in Acinetobacter baumannii Clinical Isolate, which Contributes to Th2 Response

Abstract

Acinetobacter baumannii, as a nonfermentation Gram-negative bacterium, mainly cause nosocomial infections in critically ill patients. With the widespread of multidrug-resistant Acinetobacter baumannii, the urgency of developing effective therapy options has been emphasized nowadays. Outer membrane vesicles derived from bacteria show potential vaccine effects against bacterial infection in recent study. Our present research is aimed at investigating the mechanisms involved in immune protection of mice after outer membrane vesicle immunization. As our data showed, the outer membrane vesicle from an Acinetobacter baumannii clinical strain could activate bone marrow-derived dendritic cells (BMDCs) to promote Th2 activity together with humoral immune responses to Acinetobacter baumannii-induced sepsis, which might enlighten people to have a better understanding of OMVs' role as a vaccine to prevent bacterial infections.

Factors mediating Acinetobacter baumannii biofilm formation: Opportunities for developing therapeutics

“…Various biofilm associated factors such as OmpA, Bap, Ata, PNAG and outer membrane vesicles have been studied as promising vaccine candidates for immunization against A. baumannii ( Ahmad et al., 2016 ; L.V. Bentancor et al., 2012 ; Cai et al., 2019 ; Fattahian et al., 2011 ; Jun et al., 2013 ; Luo et al., 2012 ). Other preventive strategies, such as antibiofilm polymers and coated medical devices are attractive approaches as they can inhibit bacterial colonization and prevent biofilm formation by a broad range of Gram-positive and Gram-negative bacteria.…”

Role of immunodeficiency in Acinetobacter baumannii associated pneumonia in mice

“…[ 18 ] In a recent study, it was found that the outer membrane vesicle from an A. baumannii clinical strain could activate bone marrow-derived DC to promote Th2 activity. [ 42 ] In our study, the finding that a rapid accumulation and maturation of cDCs in the lung of mice with normal immunity after A. baumannii stimulation suggested that cDCs were involved in the immune response to A. baumannii .…”

Bacterial Outer Membrane Vesicles as a Versatile Tool in Vaccine Research and the Fight against Antimicrobial Resistance

“…The interplay between OMV-associated PAMPs and innate immune cells plays an important role through induction of proinflammatory cytokine secretion by different cell types ( 31 – 33 ). Among the important PRRs, Toll-like receptors (TLRs) are capable of detecting the PAMPs present on the OMVs ( Fig.…”