CD4 and myeloid sarcoma: Notably, disturbances in the function of CD4+ Tregs have been observed in PwMS, with several studies reporting a significant decrease in suppressive ability.182,183 Additionally, CD8+ Treg function is deficient during acute exacerbation of MS.16,184 Thus, increasing Tregs in PwMS or improving Treg functionality remains an enticing potential therapeutic.