CXCL8 and secondary progressive multiple sclerosis: In particular, RRMS patients had significantly decreased levels of concentration for IL-1a [mean: 4.27 (SEM: 0.67)]; IL-8 [mean: 47.85 (SEM:13.01)]; and CCL4 [mean: 139.4 (SEM:10.18)] than the controls [IL-1a mean: 6.29 (SEM: 1.06); p < 0.05]; [IL-8 mean: 84.97 (SEM: 19.21); p < 0.01]; [CCL4 mean: 193.4 (SEM: 19.85); p < 0.01] (Table 5); however, this difference was not observed when comparing SPMS patients and HCs or RRMS and SPMS patients.