Figure
4
Fig. 4. Pollution-induced trained immunity is
characterized by enhanced secretion of inflammatory mediators in
monocytes. Impact of in vitro overnight exposure to the
particulate pollutant SRM1648a in monocytes was assessed 6 days later by
measuring the levels of pro-inflammatory cytokines including TNF, IL-6,
G-CSF, GM-CSF, and IL-1β upon stimulation with LPS or HDM (A). The
levels of chemokines, IL-8, MIP-1α, MIP-1β, GRO, and IP-10 were also
measured in monocytes after training with SRM1648a pollutant and then
LPS or HDM stimulation (B). Training with the SRM1648a pollutant did not
induce MCP-1 and MDC secretion; whereas MCP-3 level was increased in
monocytes stimulated with HDM but not LPS (C). Release of FGF-2 and EGF
was higher in supernatants from monocytes trained with the SRM1648a
pollutant compared to untrained control group after LPS or HDM
stimulation (C). The data were obtained from 2 independent Luminex
experiments in which statistical significance was determined using
non-parametric Wilcoxon sum test. Blue dots represent the average values
of Luminex data form monocyte culture supernatants obtained from 5
donors without training with SRM1648a pollutant (control group). Red
dots represent the average values of Luminex data form monocyte culture
supernatants obtained from the same 5 donors as of control group but
after training with SRM1648a. EGF: Epidermal Growth Factor; FGF 2:
Fibroblast Growth Factor 2; G-CSF: Granulocyte Colony Stimulating
Factor; GM-CSF: Granulocyte-Monocyte Colony Stimulating Factor; GRO-α:
Growth-Related Oncogene Alpha; IP10: Interferon gamma-induced Protein
10; MCP: Monocyte-Chemotactic Protein; MDC: Macrophage-Derived
Chemokine; MIP: Macrophage Inflammatory Protein.