NAAA and hemophagocytic syndrome: Inspired by the fact that platelets from ITP patients are more readily phagocytosed by macrophages, and synthesizing the physiological benefits of PLTs as drug carriers, we screened some patients with primary ITP whose platelets were modified by anti‐CD41 mAb and verified the ability of anti‐CD41‐PLT to target macrophages.[21, 22] Then the platelets products were used to construct anti‐CD41‐PLT, which mimicked platelets from ITP patients, and piggybacked VP16 with it, resulting in a platelet‐based in vivo therapeutic platform, anti‐CD41‐PLT‐VP16, and used it to treat HLH.