A C57BL/KsJ mouse model of Niemann-Pick disease (spm) belongs to the same complementation group as the major childhood type of Niemann-Pick disease type C.

A cell line (SPM-3T3) derived from a C57BL/KsJ mouse model of Niemann-Pick disease type C (NP-C) shows biochemical abnormalities similar to those in fibroblasts derived from NP-C. Somatic cell hybridization analysis of the SPM-3T3 cells and five fibroblast strains derived from NP-C patients (four childhood cases and one adult case) was carried out. The criterion for complementation was the restoration of a normal intracellular fluorescent pattern in multinucleated cells stained with filipin to demonstrate cholesterol accumulation. These cells can be assigned to two complementation groups. The SPM-3T3 cells did not complement cell strains derived from childhood-type NP-C, while they complemented a cell strain derived from an adult patient. Our results suggest that SPM-3T3 represents a genetically authentic model of a major complementation group of NP-C, and that NP-C consists of genetically heterogeneous groups.