Figure 9. Endocytosis of TLR4 is required for enhancement of PGE₂ production by IL-1β in LPS-primed monocytes.

Monocytes were left untreated or were incubated with LPS alone (10 ng/ml), or with human rIL-1β alone (100 ng/ml) or were primed with LPS for 1 h followed by 18 h incubation with rIL-1β in presence of GTPase inhibitor dynasore (10 µM, grey bars) or medium alone (open bars). At the end of incubation period, cell culture supernatants were assayed for PGE₂ production. Data are shown as fold increase in PGE₂ over untreated monocytes. Data represent average ± STDEV for monocytes obtained from three donors. Asterisks denote significant differences between cells incubated in the absence or in presence of dynasore, ***p≤0.001; *p<0.05; ns, not significant (p>0.05).