Antibiotic-induced release of small extracellular vesicles (exosomes) with surface-associated DNA

Abstract

Recently, biological roles of extracellular vesicles (which include among others exosomes, microvesicles and apoptotic bodies) have attracted substantial attention in various fields of biomedicine. Here we investigated the impact of sustained exposure of cells to the fluoroquinolone antibiotic ciprofloxacin on the released extracellular vesicles. Ciprofloxacin is widely used in humans against bacterial infections as well as in cell cultures against Mycoplasma contamination. However, ciprofloxacin is an inducer of oxidative stress and mitochondrial dysfunction of mammalian cells. Unexpectedly, here we found that ciprofloxacin induced the release of both DNA (mitochondrial and chromosomal sequences) and DNA-binding proteins on the exofacial surfaces of small extracellular vesicles referred to in this paper as exosomes. Furthermore, a label-free optical biosensor analysis revealed DNA-dependent binding of exosomes to fibronectin. DNA release on the surface of exosomes was not affected any further by cellular activation or apoptosis induction. Our results reveal for the first time that prolonged low-dose ciprofloxacin exposure leads to the release of DNA associated with the external surface of exosomes.

Minimal information for studies of extracellular vesicles 2018 (MISEV2018): a position statement of the International Society for Extracellular Vesicles and update of the MISEV2014 guidelines

“…All culture medium composition and preparation details should be provided in methods. This should be customary for cell culture studies, and is doubly important here since supplements like glucose [38][39][40], antibiotics [41], and growth factors [42] can affect EV production and/or composition. Of special note are medium components that are likely to contain EVs, such as serum.…”

Tumor microenvironment complexity and therapeutic implications at a glance

“…Multi-vesicular body (MVB)-derived extracellular vesicles (EVs) are constantly secreted into the extracellular space. These nanoparticles called exosomes are key to maintain homeostasis of their releasing (originating) cells [169][170][171][172]. They facilitate specific cell-cell interactions and stimulate several signaling pathways in their target cells, including cancer cells [173].…”

Systems biology approaches to investigating the roles of extracellular vesicles in human diseases

“…EV-associated DNA may be single-stranded DNA, mitochondrial DNA, or double-stranded DNA 39,41,42 . The DNA content associated with EVs (termed EV-DNA) may be transported within the lumen of EVs 39,40 ; however, recent studies have shown that, depending on the biological context, EV-DNA can also be found attached to the outer surface of EVs [43][44][45][46] .…”