ACKR1 and myeloid sarcoma: During MS, the endothelial cells of the BBB underwent an immunophenotypic shift, with the upregulation of intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), and atypical chemokine receptor 1 (ACKR1), thereby facilitating increased immune cell infiltration into the CNS (98).