CD4 and myeloid sarcoma: Regulation of individual miRNAs was previously identified in immune populations including lymph nodes29, whole blood30,31, serum32–35, plasma36, peripheral blood mononuclear cells (PBMCs)35,37, leukocytes38,39, CD3+ T cells40, CD4+ T cells41,42, T regulatory cells (Tregs)20, or B cells43; or in the brain within MS lesions17,44 or normal appearing white matter (NAWM)21,45,46.