NGFR and Alzheimer disease: Although knowledge on neuroimaging biomarkers has greatly increased,34 biomarkers from the serum or CSF are also required to improve the diagnostic sensitivity and specificity and monitor AD progression.35 Our data showed that p75NTR-ECD levels are strongly associated with MMSE and CDR scores, implying that p75NTR-ECD, as a novel biomarker, may be useful in distinguishing AD from other diseases.