Search

A human Tay-Sachs disease (TSD) fetal-brain-cell line is a useful model for the disease since the cells lack hexosaminidase A and accumulate the ganglioside, GM2. This brain-cell line was used to assess the effect of hexosaminidase A treatment on GM2 storage material. Entry of placental hexosaminidase A into the cells was obtained by pretreatment of the cultures with concanavalin A. Cells were analyzed periodically during six days. During the course of the experiment, GM2 in the cells decreased by approximately 50%. A substantial amount of hexosaminidase A was maintained in the cultures throughuot the experiment. This strategy was successful in mobilizing stored GM2 in TSD brain-cell cultures. Therefore, the activating factor needed for hexosaminidas A activity must be present in TSD-cultured brain cells.

Tay-Sachs disease and normal fetal cerebellar cells were maintained in culture for up to four weeks. Elevated levels of the lysosomal enzymes hexosaminidase B, beta-galactosidase, and acid phosphatase were observed in the Tay-Sachs cells in long term cultures although elevated lysosomal enzyme levels were not observed in the normal cultures. Similarly, elevated lysosomal enzyme activities were observed in Tay-Sachs cultures which had been treated with Concanavalin A.

A human glial brain cell line derived from a Tay-Sachs disease fetal cerebellum was transformed with SV-40 virus in order to obtain a transformed brain cell line which reflected the characteristics of the disease. It was shown that the transformed TSD cell line maintained an elevated level of GM2 which was similar to that shown by the nontransformed precursor. In addition, the TSD transformed line lacked hexosaminidase A.

Cultured cells derived from Tay-Sachs disease (TSD) fetal cerebellum were shown to accumulate GM2 ganglioside when compared with control cultures. In contrast, fibroblasts derived from TSD fetal lung do not contain GM2. GM2 was identified by thin-layer chromatography (TLC) and confirmed by gas-liquid chromatography (GLC). Unlike fetal TSD brain, the cell cultures established from fetal TSD brain have high concentrations of globoside and GD3 and little or no asialo GM2(GA2). The GM2 and related glycosphingolipids in these cultured cells contain a high percentage of C24:0 and C24:1 fatty acids. In spite of these differences, this TSD cell strain is unique in that it accumulates GM2, and can therefore serve as a useful in vitro model for the study of TSD.