CD27 and myeloid sarcoma: Next, we analyzed the MFI of CD180 expression in CD19+CD27−IgD+ naïve, CD19+CD27+IgD+ nonswitched (NS) memory, CD19+CD27+IgD− switched (S) memory, and CD19+CD27−IgD− double-negative (DN) B cells and found a significantly decreased level of CD180 expression in NS B cells of both the NMOSD and MS patients compared to HC (Figure 2(c)).