Additionally, recent reports found high levels of CD138 protein in the CSF of patients with MS at all disease stages, as well as CD138+ plasma cells being present in a perivascular location in PM material from one patient with relapsing remitting multiple sclerosis (RRMS), suggesting that CD138 could act as a specific CSF biomarker for MS [16]. Here, SDC1 is linked to myeloid sarcoma.