Fig. 4. LPS detection and rapid induction of shock in primed mice occur independently of TLR4.

(A) BMMs were primed overnight with poly(I:C) and then transfected with S. minnesota RE595 LPS. Cytotoxicity was determined 2 hours later. (B–C) Poly(I:C) and Pam₃CSK₄ primed macrophages were incubated with the indicated combinations of CTB (20µg/mL) and LPS from E. coli O111:B4 (1µg/mL). Cytotoxicity (B) and IL-1β secretion (C) were determined 16 hours later. Data are representative of at least 3 experiments; error bars indicate standard deviation of technical replicates (A–C). (D) Survival of mice challenged with the indicated doses of Escherichia coli LPS, or primed with LPS and then re-challenged 7 hours later. Data are pooled from three experiments; n = 9 per condition. (E) Survival of mice primed with LPS (400μg/kg) or poly(I:C) (10µg/kg) and then challenged 7 hours later with LPS (100ng/kg). Data are pooled from three experiments; n = 7 per LPS prime group and n = 8 for poly(I:C) prime group. (F) Rectal temperatures of mice in panel (E) after LPS challenge. Data are representative of 3 experiments; n = 4 per condition. (G) Survival of poly(I:C) primed mice challenged 6 hours later with LPS (10ng/kg). Data are pooled from 3 experiments, n = 11 (C57BL/6) or 12 (Casp11^−/−). (H) Mice were primed with poly(I:C) and then challenged 6 hours later with LPS (100ng/kg) and monitored for survival. 1 h before LPS challenge, mice were given 5mg/kg of COX-1 inhibitor or DMSO control. Data are pooled from 2 experiments; n = 11 per condition.