In the studies of epilepsy caused by tuberous sclerosis syndrome (TSC), focal cortical dysplasia (FCD), and medial temporal lobe epilepsy (MTLE), He et al. found that the expression of both IL-17 and IL-17R was upregulated at the mRNA and protein levels by immunofluorescence staining of surgically resected tissues from human patients. Here, IL17A is linked to epilepsy.