A few proteins have emerged as robust markers to monitor neuroinflammation in Alzheimer’s disease (AD) or multiple sclerosis due to their reproducible relation to pathological features of the disease: soluble TREM2 (sTREM2) as a marker of microglial activation [14], YKL-40 as an astroglia stimulation molecule [8], CD14 as myeloid cell activation protein [16] and neurofilament light chain (NF-light) as a correlate of neuronal damage. The gene discussed is TREM2; the disease is multiple sclerosis.