Figure 5

Choline suppresses TNF release from endotoxin-stimulated human whole blood (A) and human macrophages (B). (A) Whole blood was treated for 10 min with the indicated concentrations of choline prior to endo-toxin (10 ng/mL) challenge at 37° C. Plasma TNF was determined by ELISA 4 h later. Data represent the mean ± SEM of duplicate determinations from five donors (*P < 0.0001) as compared with the lowest choline concentration tested). (B) Peripheral blood mononu-clear cells (PBMCs) were isolated from adult donors and were differentiated into macrophages. Macrophages were treated with the indicated concentration of choline 10 min prior to the addition of endotoxin (20 ng/mL). Culture supernatants were harvested 4 h later and the level of TNF secreted into the media was determined by ELISA. Data represent the mean ± SEM of at least three experiments conducted in duplicate from independent donors (*P < 0.02) as compared with the lowest choline concentration tested.