Sustained Immunoparalysis in Endotoxin-Tolerized Monocytic Cells

Figure 5

Immunotolerant THP-1 monocytes demonstrate altered metabolism after LPS pretreatment. Cells were stimulated with LPS (1 μg/ml) for 48 h and rested for 5 d after LPS removal. Afterwards, they were challenged with LPS (1 μg/ml) or PBS as indicated. (a) demonstrates a representative measurement of LPS-tolerized and nontolerized cells over 20 h. Oxygen rates (b, c) of monocytes left untreated or preincubated with LPS. Pooled data from () independent measurements each with 4 technical replicates. MTT assay (b, -5), LDH activity (c, ), lactate secretion (d, ), and NAD+/NADH (e, ) levels were detected. ; , , and .