All phenotypic analyses and cell cultures are performed using previously validated protocols. Our ultimate goal is to correlate quantitative and functional changes of subsets composing the systemic B-cell population with the grading and evolution of MS. Such a strategy could lead to identify which MS patients should receive treatment targeting B cells and when. Further, it may offer a rationale for alternative forms of cell therapy that could introduce for example autologous purified B regulator cells after depletive strategies.