Figure 7.

The anti-inflammatory properties LL-37-induced, secondarily necrotic PMN are independent of peptide antiendotoxic activity. Human PMN were incubated for 20 h in the presence or absence of LL-37 or partial peptides p1, p2, or p3 at the concentrations indicated. PMN were resuspended in X-vivo 10 media with 10% FCS (A), resuspended in serum-free X-vivo 10 media (B and D), or used unwashed in the IMDM + 10% FCS media supernatant, in which they were incubated overnight (C). MDM were incubated with these PMN, with concomitant exposure to 10 ng/ml E. coli 0111:B4 LPS (A, C, and D) or 3 μg/ml rhCD40L + 5 ng/ml rhIFN-γ (B) for 18 h. Activated MDM without PMN, in the presence or absence of peptides, were also studied as controls and to evaluate direct antiendotoxic activity. Supernatants were evaluated for cytokine responses. Significance was assessed by one-way ANOVA with Bonferroni’s multiple comparison test; n ≥ 3 donors; *, P ≤ 0.05; **, P ≤ 0.01; ***, P ≤ 0.001, compared with activated MDM in the absence of PMN under the same conditions.