CXCL13 and myeloid sarcoma: An example of how this model is relevant to MS is in the identification of CXCL13 [Chemokine (C-X-C motif ligand 13)], a B cell-active chemokine, as a strongly upregulated cytokine locally within the CNS both in TMEV infected mice (46, 47) and MS (48, 49).