EOMES and primary progressive multiple sclerosis: We here showed that Eomes+ Th cells are elevated in SPMS patients while having a low expression in PPMS patients, which is in line with previous studies.10 While genome-wide association studies indicate shared genetic risks between secondary progressive and primary progressive multiple sclerosis, the differences in immune cell phenotypes, particularly the enrichment of Eomes-expressing T helper cells, could reflect differing inflammatory activity in SPMS and PPMS, not necessarily distinct pathogenic pathways.