Figure 4.

MTT assay using the purified I44 and I49 dAbs as the inhibitors of TNF-α cytotoxic effect. Different concentrations of dAbs (ranging from 0.023 to 1.83 µM for I44 and 0.047 to 3.82 µM for I49) and adalimumab was incubated with 0.0057 nM of TNF-α before addition onto L929 cells. After 24 h treatment, the neutralizing potency of I44 and I49 dAbs on TNF-α induced cell cytotoxicity was determined. Each data point is the average of three independent experiments, and the error bar is the corresponding standard error calculated by Prism program