Immune status of patients with haemophilia A before exposure to factor VIII: first results from the HEMFIL study

Summary Previous cross‐sectional studies showed that some patients with haemophilia A (HA) without inhibitor presented a pro‐inflammatory profile during factor VIII (FVIII) replacement therapy. Furthermore, an anti‐inflammatory/regulatory state was described in HA patients after inhibitor development. However, no study investigated the levels of these biomarkers before exposure to exogenous FVIII. This study investigated the immunological profile of previously untreated patients (PUPs) with HA in comparison with non‐haemophiliac boys. A panel of chemokines and cytokines was evaluated in the plasma of 40 PUPs with HA and 47 healthy controls. The presence of microparticles was assessed in the plasma of 32 PUPs with HA and 47 healthy controls. PUPs with HA presented higher levels of CXCL8 (IL8), IL6, IL4, IL10, IL2, IL17A (IL17), and lower levels of CXCL10 (IP‐10) and CCL2 (MCP‐1) than the age‐matched healthy controls (P