The severity of meningeal inflammation and the presence of TLSs in the MS brain is directly correlated with increased levels of TNF and IFN genes, along with their protein expressions in the meninges and cerebrospinal fluid compartments.445 This body of evidence underscores the significant role of TLSs in the pathogenesis and progression of MS, highlighting their potential as targets for therapeutic intervention. This evidence concerns the gene IFNA1 and myeloid sarcoma.