Because of the inverse correlation between LFB intensity and PGN immunolabelling, we examined host gene expression in adjacent serial tissue sections by Nanostring transcript array in sections from each tissue block which disclosed induction of immune genes, NFKB1, RIPK1 and IL-12A, in MS brains and showed the highest correlations with PGN expression. Here, IL12A is linked to myeloid sarcoma.