Effects of Ocrelizumab Treatment on Immune Cells in Lymph Nodes in Multiple Sclerosis

B cell-depleting therapies, such as ocrelizumab, are among the most effective medications currently available for the treatment of multiple sclerosis (MS). This suggests that B cells play a very important role in MS. While B cells are rapidly eliminated from the blood of patients treated with medications like ocrelizumab, little is known about how effectively B cells are eliminated from lymph nodes, which are important sites of B cell activation. This study is being conducted to determine to what extent B cells are targeted in lymph nodes following ocrelizumab treatment, which may have important consequences for long-term MS outcomes.