CSF Free Light Chains as a Marker of Intrathecal Immunoglobulin Synthesis in Multiple Sclerosis: A Blood-CSF Barrier Related Evaluation in a Large Cohort oleh Makbule Senel, Fatemeh Mojib-Yezdani, Ulrike Braisch, Franziska Bachhuber, Jan Lewerenz, Albert C. Ludolph, Markus Otto, Hayrettin Tumani, Hayrettin Tumani