Moreover, our initial study used fluorescent light microscopy to screen immunolabelling of axon bundles with patient sera on mouse brain sections.11 12 This microscopic method may have underestimated the thin filamentous immunopositive labelling for NF-M and could not sufficiently differentiate it from the thick filamentous labelling by multiple sclerosis (MS) sera. Here, NEFM is linked to myeloid sarcoma.