FIGURE 5.

Activation of HEK/TLR4 cells by incubation of the monomeric form of MD-2 with LOS·sCD14. The HEK/TLR4 cells were incubated overnight with increasing amounts of conditioned medium containing MD-2 (•), isolated dimer (*), or monomer (▵) sMD-2 in the presence of [¹⁴C]LOS·sCD14 (2 nm)(A) or with increasing amounts of monomer sMD-2 in the presence of [¹⁴C]LOS·sCD14 (60 pm) or [¹⁴C]LOS aggregates (20 nm)(B). Cell activation was measured by determining accumulation of extracellular IL-8. Extracellular IL-8 was measured by ELISA. The results shown represent the means ± S.E. of three experiments, each in triplicate.