Moreover, activated astrocytes produce CXCL1 (another CXCR2 ligand) at the lesion edges in EAE mice, and high levels of CXCL1, CXCL5, and CXCL8 are detected in the serum of MS patients, supporting a role for CXCR2 in the infiltration of neutrophils into the CNS in this disease (36, 44). This evidence concerns the gene CXCR2 and myeloid sarcoma.