Differential regulation of different TLR expression in B cells. Purified resting tonsillar B lymphocytes were stimulated in vitro for the indicated time periods (2 × 109 cells/L) with (A) anti-μ (10.5 μg/mL), (B) CpG (6 μg/mL), and (C) SAC (1/20 000). Total RNA was prepared from control resting B cells (Resting), buoyant in vivo–activated B cells (GC), and in vitro–stimulated B cells (4h, 12h, 24h) converted to cDNA and analyzed for expression of TLR1, TLR4, and TLR7 by real-time PCR as outlined in “Materials and methods.” β-Actin expression was used to standardize all results. Results are expressed as fold induction over levels of RNA in resting cells and represent the mean ± SEM (n = 3) for a representative experiment. These results are representative of 3 independent experiments.
