Induction of Innate Memory in Human Monocytes Exposed to Mixtures of Bacterial Agents and Nanoparticles

We assessed whether concomitant exposure of human monocytes to bacterial agents and different engineered nanoparticles can affect the induction of protective innate memory, an immune mechanism that affords better resistance to diverse threatening challenges. By using an in vitro model, cells were exposed to nanoparticles of different chemical nature, shape and size either alone or admixed with LPS, cell activation was then assessed in terms inflammatory (TNF, IL-6) and anti-inflammatory cytokines (IL-10, IL-1Ra) production. After a period of resting and return to baseline conditions, cells were re-challenged with LPS and their secondary “memory” response measured. Results show that nanoparticles alone are essentially unable to generate memory, while LPS induced a tolerance memory response (less inflammatory cytokines, equal or increased anti-inflammatory cytokines). LPS-induced tolerance was only partially and variably affected by the co-presence of nanoparticles during the memory generation phase. While overall it appears that nanoparticles do not have a significant effect in modulating LPS-induced memory, a substantial donor-to-donor variability was observed, with cells from some donors showing measurable nanoparticle-dependent memory effects both towards increase and decrease of the LPS-induced tolerance. Thus, while the effects on LPS-induced memory do not seem to depend on nanoparticle chemical nature, size or shape, such effects are strongly donor-dependent.

DELLA CAMERA Giacomo;  TINGHAO Liu;  WENJIE Yang;  YANG Li;  F. PUNTES Victor;  GIORIA Sabrina;  ITALIANI Paola;  BORASCHI Diana; 

2022-11-28

MDPI

JRC129342

1661-6596 (online),   

https://www.mdpi.com/1422-0067/23/23/14655,    https://publications.jrc.ec.europa.eu/repository/handle/JRC129342,   

10.3390/ijms232314655 (online),