Our recent study comparing serum and matching urine immune markers between healthy controls and people with multiple sclerosis (MS) showed higher levels of immune markers (IP-10, IL-1ra, TNF-alpha, and RANTES) in the serum of people with MS compared to healthy controls, whereas, in urine, the result was the opposite to the matching serum (42). Here, CXCL10 is linked to multiple sclerosis.