Interestingly, peripheral LPS exposure led to downregulation of some genes such as Kcnj9 (Liu et al., 2019) and Kif21b (Asselin et al., 2020), the deficiency of which has been associated with the occurrence of neurological and neurodevelopmental disorders, again highlighting the importance of the immune system-brain axis. This evidence concerns the gene KIF21B and neurodevelopmental disorder.