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Abstract Bacteria utilize a cell density‐dependent communication system called quorum sensing (QS) to coordinate group behaviors. In Gram‐positive bacteria, QS involves the production of and response to auto‐inducing peptide (AIP) signaling molecules to modulate group phenotypes, including pathogenicity. As such, this bacterial communication system has been identified as a potential therapeutic target against bacterial infections. More specifically, developing synthetic modulators derived from the native peptide signal paves a new way to selectively block the pathogenic behaviors associated with this signaling system. Moreover, rational design and development of potent synthetic peptide modulators allows in depth understanding of the molecular mechanisms that drive QS circuits in diverse bacterial species. Overall, studies aimed at understanding the role of QS in microbial social behavior could result in the accumulation of significant knowledge of microbial interactions, and consequently lead to the development of alternative therapeutic agents to treat bacterial infectivity. In this review, we discuss recent advances in the development of peptide‐based modulators to target QS systems in Gram‐positive pathogens, with a focus on evaluating the therapeutic potential associated with these bacterial signaling pathways.
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Vasculature-on-a-chip technologies as platforms for advanced studies of bacterial infections
Bacterial infections frequently occur within or near the vascular network as the vascular network connects organ systems and is essential in delivering and removing blood, essential nutrients, and waste products to and from organs. In turn, the vasculature plays a key role in the host immune response to bacterial infections. Technological advancements in microfluidic device design and development have yielded increasingly sophisticated and physiologically relevant models of the vasculature including vasculature-on-a-chip and organ-on-a-chip models. This review aims to highlight advancements in microfluidic device development that have enabled studies of the vascular response to bacteria and bacterial-derived molecules at or near the vascular interface. In the first section of this review, we discuss the use of parallel plate flow chambers and flow cells in studies of bacterial adhesion to the vasculature. We then highlight microfluidic models of the vasculature that have been utilized to study bacteria and bacterial-derived molecules at or near the vascular interface. Next, we review organ-on-a-chip models inclusive of the vasculature and pathogenic bacteria or bacterial-derived molecules that stimulate an inflammatory response within the model system. Finally, we provide recommendations for future research in advancing the understanding of host–bacteria interactions and responses during infections as well as in developing innovative antimicrobials for preventing and treating bacterial infections that capitalize on technological advancements in microfluidic device design and development.
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- Award ID(s):
- 2301586
- PAR ID:
- 10498000
- Publisher / Repository:
- AIP Publishing
- Date Published:
- Journal Name:
- Biomicrofluidics
- Volume:
- 18
- Issue:
- 2
- ISSN:
- 1932-1058
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1063/5.0179281
