sentence: Both proneurotrophins and neurotrophins bind to VPS10p members ( such as Sortilin , SorCS2 , and SorCS3 ) , p75NTR and Trk , but in general the affinity of proneurotrophin is higher for VPS10p members while that of neurotrophins is higher for p75NTR and Trk , although there is one exception ; NGF binds with higher affinity to SorCS3 than does proNGF .