The importance of CysLTR1-signaling in MS is gaining more interest as CysLTR1 is found to be elevated in the blood of PwMS, with an increase on CD4+ T lymphocytes, but also on astrocytes and microglia in MS lesions compared to normal appearing white matter in post-mortem brain tissue [123]. The gene discussed is CYSLTR1; the disease is myeloid sarcoma.