Viability of LPS-stimulated MoDCs exposed to inhibitors.

Peripheral blood monocytes cultured with GM-CSF and IL-4 for 7 days were incubated with LPS with or without inhibitors for 24 or 48 hours. The percentage of cells surviving at the end of this incubation was measured by flow cytometry. Only cells that did not bind FITC-conjugated annexin V and did not take up propidium iodide were classified as viable. PD indicates PD98059 (MKK1/MEK inhibitor); LY, LY294002 (PI3 kinase inhibitor); SB, SB203580 (p38SAPK inhibitor). Blocking the PI3 kinase pathway has a marked effect on MoDC survival, whereas blocking the MAPK or p38SAPK pathway does not affect MoDC survival even after 48 hours. Results are the mean ± SEM of 4 experiments.