<i>P. gingivalis</i> differentially suppresses CD14^hi/lo M1 and M2 MΦ NFκB activity.

<p>CD14^lo M1 (a) CD14^hi M1 (b), CD14^lo M2 (c) and CD14^hi M2 (d) MΦ subsets were pre-stimulated (tolerised) with either 100 ng/ml PG-LPS (unshaded) or 1×10⁷ cells/ml HKPG (shaded) for 24 hours prior to stimulation with PG-LPS or HKPG and incubated for a further 18 hours (untolerised controls indicated in bold). NFκB activation is expressed as the mean absorbance units A_620nm ± SD for the CD14^hi/lo M1 and M2 MΦ subsets. Data displayed represents triplicate samples for n = 3 replicate experiments. Significant effects compared to the un-tolerised stimulus control (bold) for each MΦ subset are indicated as *p<0.05, ***p<0.001 and ns, not significant.</p

Peptidoglycan differentially cross-tolerises <i>P. gingivalis</i>-stimulated CD14^hi/lo M1 and M2 MΦ subsets.

<p>CD14^hi/lo M1 and M2 MΦ subsets exhibit a differential cross-tolerisation of cytokine production and NFκB activity to the <i>P gingivalis</i> PAMPs, PG-LPS and HKPG. CD14^lo M1, CD14^hi M1, CD14^lo M2 and CD14^hi M2 MΦ subsets were pre-stimulated (tolerised) with 10µg/ml peptidoglycan (PGN) for 24 hours prior to stimulation with PG-LPS or HKPG and incubated for a further 18 hours. Tolerisation/suppression of the pro-inflammatory cytokines (TNFα, IL-1β and IL-6), the anti-inflammatory cytokine (IL-10) and the transcription factor activity (NFκB) is expressed as the mean percentage suppression ± SD of non-tolerised stimulation controls. Data displayed represents triplicate samples for n = 3 replicate experiments.</p

M1 & M2 MΦs display differential cytokine profiles in response to PG-LPS and HKPG.

<p>THP-1-derived M1 and M2 MΦs were generated by differentiating THP-1 monocytes with either 25 ng/ml phorbol 12-myristate 13-acetate (PMA) for 3 days or 10 nM 1,25-(OH)₂ vitamin D₃ for 7 days, respectively. M1 (bold) and M2 (shaded) MΦ subsets were stimulated with either 100 ng/ml PG-LPS (a, b and c) or 1×10⁷ cells/ml HKPG (d, e and f). Cytokine production is expressed as the mean ± SD in pg/ml for TNFα (a & d), IL-1β (b & e) and IL-6 (c & f). Data displayed represents triplicate samples for n = 3 replicate experiments. Significant differences in cytokine production between activated M1 and M2 MΦs are indicated as *p<0.05, **p<0.01, ***P<0.001 and ns, not significant.</p

PG-LPS exhibits weak endotoxin activity in THP-1-derived macrophages.

<p>THP-1-derived M1-like (PMA) and M2-like (Vit D₃) MΦs were either unstimulated (control) or stimulated with 100 ng/ml PG-LPS, 100 ng/ml <i>E. coli</i> K12 LPS (TLR4) or 10 µg/ml LTA (TLR2) for 18 hours. Endotoxin activity was investigated by TNFα secretion, presented as the mean ± SD in pg/ml. Data displayed is representative of triplicate samples for n = 3 replicate experiments.</p

<i>P. gingivalis</i> differentially suppresses CD14^hi/lo M1 and M2 MΦ IL-10 production.

<p>CD14^lo M1 (a) CD14^hi M1 (b), CD14^lo M2 (c) and CD14^hi M2 (d) MΦ subsets were pre-stimulated (tolerised) with either 100 ng/ml PG-LPS (unshaded) or 1×10⁷ cells/ml HKPG (shaded) for 24 hours prior to stimulation with PG-LPS or HKPG and incubated for a further 18 hours (untolerised controls indicated in bold). Anti-inflammatory IL-10 cytokine production is expressed in pg/ml as the mean ± SD for the CD14^hi/lo M1 and M2 MΦ subsets. Data displayed represents triplicate samples for n = 3 replicate experiments. Significant effects compared to the un-tolerised stimulus controls (bold) for each MΦ subset are are indicated as*p<0.05, **p<0.01, ***p<0.001 and ns, not significant.</p