At first sight, this evidence seems conflicting with the observation, in an untreated MS cohort undergoing anti-CD20 mAb treatment, of an inverse correlation between both CD20+CD8+ and brain MRI gadolinium-enhancing lesions before treatment, and between baseline CD20+CD8+ levels and new brain lesions developing from week 12 following treatment start [34]. Here, MS4A1 is linked to myeloid sarcoma.