PF4 and amyotrophic lateral sclerosis: PF4 is a specific protein synthesized by platelets, and the neuroprotective effects of PF4 have been demonstrated in mouse models of traumatic brain injury (Nebie et al., 2021), amyotrophic lateral sclerosis (Gouel et al., 2022), and Parkinson’s disease (Chou et al., 2017).