C9 and myeloid sarcoma: Therefore, given that complement protein levels have been suggested as potential plasma biomarkers due to their increase in MS cases [35,38,39,40], a hint that is also supported by the biological background as described before [34], the finding in [35] does not necessarily contradict our result, but leads to the need to pinpoint plasma complement components levels, and therefore also plasma C9 levels, as candidate plasma MS biomarkers which should be further investigated in confirmatory studies.