Hemopexin infusion decreases NETs in TNF-α–stimulated SCD mice and protects SCD mice from NET-associated hypothermia. (A) Quantification of plasma heme concentrations of TNF-α–stimulated SCD mice, vehicle pretreated (white circle, n = 13) or Hx pretreated (gray circle, n = 13) (mean ± SEM, **P < .01). (B) Quantification of NETs in the lungs of TNF-α–stimulated SCD mice, vehicle pretreated (white bar, n = 6) or Hx pretreated (gray bar, n = 10). Results presented are the average values of independent experiments with sex- and age-matched mice (mean ± SEM, **P < .01). (C) Quantification of NET biomarkers, plasma DNA (left) and plasma nucleosome (right), from TNF-α–challenged SCD mice, vehicle pretreated (white circle, n = 14) or Hx pretreated (gray circle, n = 10) (Mann-Whitney test, median [IQR], **P < .01). (D) Quantification of plasma MPO activity of TNF-α–challenged SCD mice, vehicle pretreated (white circle, n = 6) or Hx pretreated (gray circle, n = 6) (Mann-Whitney test, median [IQR], **P < .01). (E) Decrease in rectal temperature of TNF-α–stimulated SCD mice, pretreated with vehicle (white circle, n = 13) or Hx (gray circle, n = 13; mean ± SEM, *P < .05).