After comparing the differential gene expression, the volcano plot (Fig. 4a; Supplementary Data 4) showed that T cells in TDL upregulated genes associated with immunity (GZMK, GZMA, and CXCL13) and MS susceptibility gene RGS1 and downregulated genes associated with myelination (PLP1), glial cell differentiation (GFAP), and tumor cell proliferation (SOX2-OT). The gene discussed is PLP1; the disease is neoplasm.