Increased production of calprotectin, a biomarker for inflammation, in F8^−/−punctured mice and HA patients. (A) The inflammation marker calprotectin was higher in serum of F8^−/− punctured mice at 2 weeks (58 ± 23 pg/mL; n = 3) and 12 weeks (21 ±7 pg/mL; n = 7) compared with unpunctured F8^−/− mice, where calprotectin was not detectable (0 ± 0 pg/mL; n = 3). (B) Calprotectin levels in hemophilia A patients were 57 ± 4 pg/mL (n = 40), in healthy controls they were 32 ± 3 pg/mL (n = 23) and in disease controls they were 38 ± 2 pg/mL (n = 36) (see “Methods” for details). *P < .001.