Among the now eight genetic types of neuronal ceroid-lipofuscinoses (NCL), CLN1 to CLN8, CLN2 is considered classic late-infantile NCL. It was originally described by Janský in a family of eight children with four of them affected [Janský J (1908) Sborn Lék 13:165-196] and, subsequently, by Bielschowsky in a family of three children each of whom was affected, and, hence, termed Janský-Bielschowsky type of NCL. Earlier, archival studies of Bielschowsky's original post-mortem tissue blocks had documented accumulation of autofluorescent lipopigments with a curvilinear ultrastructure. In a subsequent study, described here, immunohistochemical absence of the CLN2-related lysosomal enzyme tripeptidyl peptidase-I and two heterozygous mutations in the CLN2 gene could be demonstrated in these archival tissues, further corroborating the identity of Bielschowsky's familial disorder and CLN2 described by M. Bielschowsky at the beginning of the last century. Furthermore, these immunohistochemical and mutational investigations underscore the value of archival tissue studies.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.