Cyclic stretch increases HMGB1 expression in a TLR4-dependent fashion.

(A) Cell culture media with or without cyclic stretch were concentrated and HMGB1 contents were detected by Western blot. (B) HMGB1 in cell culture media with or without stretch was directly measured by ELISA. (C) Media of the cells which transfected with nonspecific siRNA control (consiRNA) or TLR-4-specific siRNA (TLR4 siRNA) with or without stretch (con vs. cyclic S) were concentrated and HMGB1 contents were measured by Western blot. (D) HMGB1 in media of the transfected cells following 6h cyclic stretch (cyclic S) was measured by ELISA. **P<0.01, ***P<0.001 compared with control. Each stretching group collected from three wells and represented a single experiment, the bar graphs illustrate data representative of three independent experiments.