Several studies have documented the increased number of C3aR1 and C5aR1 cells in MS lesions (Gasque et al., 1998; Ischenko et al., 1998; Ingram et al., 2014), including cortical GM lesions (Watkins et al., 2016; Loveless et al., 2018). The gene discussed is C3AR1; the disease is myeloid sarcoma.