Goals: The aim of this research was to evaluate whether micronized cells (MCs) from selected biotherapeutic bacteria have the ability to effectively modulate the polarization of monocyte/macrophage subpopulations to advantageously provide a first line of defense against infections.
Background: Inflammation is a reaction of the host to viral and bacterial infections with the physiological purpose of restoring tissue homeostasis. However, uncontrolled or unresolved inflammation can lead to tissue damage, giving rise to a plethora of chronic inflammatory diseases. The monocytes/macrophages play a key role in the initiation and resolution of inflammation through different activation programs.
Study: MCs were obtained from Bifidobacterium lactis BS01 strain using a Bioimmunizer extraction protocol. Monocytes were stimulated with the probiotic strain and/or MCs (10 mg/mL) for 24 hours and 5 days. Monocyte/macrophage differentiation was evaluated by cytometry analysis of surface markers and the activity of the 2 subpopulations on oxidative stress was assessed in an in vitro oxidative stress model with a spectrophotometric test.
Results: The MCs have been shown to modulate considerably the 2 subpopulations of human monocytes/macrophages, both the "patrolling subpopulation" and the "inflammatory subpopulation," thus highlighting a strong immunostimulatory effect. In addition, MCs are able to mitigate significantly the oxidative stress induced by homocysteine in an in vitro model.
Conclusions: Our findings suggest that MCs derived from the biotherapeutic strain BS01 could represent a possible therapy aimed to effectively prevent and/or cure viral, bacterial, fungal, or protozoal diseases, as well as prevent and/or treat inflammatory processes triggered by external pathogenic agents.