HDAC9 and myeloid sarcoma: Several studies on EAE point to the potential use of histone deacetylase (HDAC) inhibitors (Camelo et al. 2005; Ge et al. 2013; Zhang et al. 2012) and activators (Zhang et al. 2009) as transcriptional modulators to ameliorate MS, suggesting that histone modification, chromatin modifying enzymes, and chromatin organization pathways might also be involved in the differential clinical outcome presented with aging in EAE.