Placental inflammasome activation causes PE. (A-B) Pregnancy outcome at day 12.5 p.c. after IV. EV (mouse endothelial cell–derived) injection at days 10.5 p.c. and 11.5 p.c. into pregnant NLRP3^+/− females mated to NLRP3^−/− males. (A) Representative images of uterus (left panel), placenta (right top panel), and embryo (right bottom panel) and (B) bar graph quantifying embryonic survival. (C) Elevated sFlt-1 plasma levels in EV-treated NLRP3^+/− pregnant female mice at day 12.5 p.c. following EV injection; bar graphs summarizing results. (D-E) Pregnancy outcome at day 12.5 p.c. after IV EV injection at days 10.5 p.c. and 11.5 p.c. in NLRP3^−/− females mated to NLRP3^+/+ males. (D) Representative images of uterus (left panel), placenta (right top panel), and embryos (right bottom panel) along with (E) bar graph quantifying embryonic survival. (F) Elevated sFlt-1 plasma levels in EV-injected pregnant mice following mating NLRP3^−/− females with NLRP3^+/+ males; bar graphs summarizing results. Size bar represents 1 mm for embryo and placenta (A,D). Data shown represent mean ± SEM from at least 8 embryos analyzed from 3 different litters or 5 pregnant females of each group; control mice (C) were injected with the supernatant obtained after the last PBS wash during EV isolation. *P < .05 (relative to control, C). (B) ANOVA; (C-F) Student t test.