2019年 9月 3日〜6日（ロッテルダム、オランダ）
タイトル； Development of drug screening system using neural stem cells derived from a patient with Type II Gaucher Disease.
（熊本大学 大学院生命科学研究部 小児科学講座）
Type II Gaucher disease （GD）is a lysosomal storage disease caused by a deficient activity of the enzyme glucocerebrosidase (GC). Glucosylceramide (GlcCer) and glucosylsphingosine (GlcSph) were accumulated in the nervous systems of patients with type II GD. The onset frequency of type II GD in Japan is significantly higher compared to those in Europe and America, and was accounted for one-third of all GD. The chaperon treatment such as ambroxol may be restrictedly effective in some patients with neuropathic GD, however, the effective treatment for type II GD have not been definitely confirmed. This aim of study is to develop the effective treatment for type II GD.
We introduced the four factors (KLF4, OCT3/4, SOX2, c-MYC) into lymphocytes from a patient with type II GD and acquired the type II GD iPS cells. Moreover, we differentiated the type II GD iPS cells into the type II GD neural stem cells (NSCs) using Gibco®PSC Neural Induction Medium. The type II GD NSCs were cultured in the special neuron culture medium for 2 months and developed into neurons. We analyzed the characters and functions in neurons from patients with type II GD and neurons from normal healthy control.
The activity of the enzyme GC in type II GD NSC was significantly lower than those in normal heathy control NSC. The GlcCer in the type II GD neuron was not more accumulated than those in normal heathy control neuron, however, the GlcSph in the type II GD neuron was more accumulated than those in normal heathy control neuron. The lysosomal-associated membrane protein 1 (LAMP-1) was significantly more expressed in the type II GD NSC in gene and protein expression levels. We developed a drug screening system using LAMP-1 as a marker protein in the IN Cell Analyzer 6000.
We screened 1392 compounds, and 120 compounds decreased LAMP-1 expression. In the more detailed examination, we selected 10 compounds as the possible candidates of medicine for type II GD. In the future, we will find out effective medicine for type II GD neuron because we could develop the drug screening system for type II GD NSC and neuron.