Fibroblast screening for chaperone therapy in beta-galactosidosis.
We performed screening of beta-galactosidase-deficient fibroblasts for possible chemical chaperone therapy using N-octyl-4-epi-beta-valienamine (NOEV) in patients with GM1-gangliosidosis and Morquio B disease (beta-galactosidosis). Fibroblasts were cultured with NOEV for 4 days and beta-galactosidase activity was measured. Mutation analysis was performed simultaneously. Two separate criteria were set for evaluation of the chaperone effect: a relative increase of enzyme activity (more than 3-fold), and an increase up to more than 10% normal enzyme activity. Among the 50 fibroblast strains tested, more than 3-fold increase was achieved in 17 cell strains (34%), and more than 10% normal activity in 10 (20%). Both criteria were satisfied in 6 (12%), and either of them in 21 (42%). Juvenile GM1-gangliosidosis was most responsive, and then infantile GM1-gangliosidosis. This enhancement was mutation-specific. We estimate that the NOEV chaperone therapy will be effective in 20-40% of the patients, mainly in juvenile and infantile GM1-gangliosidosis patients. A molecular design may produce mutation-specific chaperone compounds for the other disease phenotypes. This cellular screening will be useful for identification of human patients with beta-galactosidase deficiency for chaperone therapy to be started in the near future.
Iwasaki
Hiroyuki
H
Clinical Research Center, International University of Health and Welfare, 2600-1 Kita-Kanemaru, Otawara, Japan. hiwasaki@iuhw.ac.jp
Watanabe
Hiroshi
H
Iida
Masami
M
Ogawa
Seiichiro
S
Tabe
Miho
M
Higaki
Katsumi
K
Nanba
Eiji
E
Suzuki
Yoshiyuki
Y
D001120:Arginine / Q000235:genetics; D002478:Cells, Cultured; D053138:Cyclohexenes; D004305:Dose-Response Relationship, Drug; D004353:Drug Evaluation, Preclinical / Q000379:methods; D005347:Fibroblasts / Q000187:drug effects*; D016537:Gangliosidosis, GM1 / Q000235:genetics / Q000473:pathology*; D005838:Genotype; D005973:Glutamine / Q000235:genetics; D006595:Hexosamines / Q000494:pharmacology* / Q000627:therapeutic use; D006801:Humans; D018832:Molecular Chaperones / Q000494:pharmacology* / Q000627:therapeutic use; D009085:Mucopolysaccharidosis IV / Q000235:genetics / Q000473:pathology*; D009154:Mutation; D010641:Phenotype; D001616:beta-Galactosidase / Q000235:genetics / Q000378:metabolism
D053138:Cyclohexenes; D006595:Hexosamines; D018832:Molecular Chaperones; D005973:Glutamine; C030791:valienamine; D001120:Arginine; D001616:beta-Galactosidase