To date, discordant data are available on the correlation between blood CD14 expression and disease activity.25, 29 In particular, an inverse correlation was found between serum levels of sCD14 and disease activity, showing that CD14 may be a good indicator of stable MS.30 Thus, a more comprehensive analysis of the CD14/CD163 CSF balance at the time of diagnosis is mandatory as it may indicate a new potential tool to better evaluate the intrathecal stage of macrophage activation to predict and monitor MS evolution. Here, CSF2 is linked to myeloid sarcoma.