SEMA4D and myeloid sarcoma: In fact, the protein was shown to activate microglia and compromise the stability of the BBB in in vivo models of MS and hypoxia (Smith et al., 2015; Kuklina, 2019) whereas in other studies, SEMA4D was shown to mitigate LPS-induced microglial activation in vitro (Toguchi et al., 2009) and its silencing compromised neuronal recovery from spinal cord injury in the zebrafish model (Peng et al., 2017).