Gm04693

STHdhQ7 and STHdhQ111 cells were obtained from HD Community BioRepository Collection (New Jersey, USA) and cultured in Dulbecco's modified eagle medium (DMEM) supplemented with 10% fetal bovine serum (FBS, Mediatech, Inc. VA, USA), 1% glutamine and 1% penicillin/streptomycin at 33°C. Early passages of STHdh (less than 20 passages) were used in the studies. Primary fibroblasts, GM04693 from a HD individual (onset at age 41 years) and AG02222 from a normal subject, were obtained from the Coriell Institute for Medical Research and cultured in DMEM supplemented with 20% FBS, 1% glutamine and 1% penicillin/streptomycin at 37°C. Phoenix-Ampho cells were purchased from ATCC (Manassas, VA, USA) and cultured in DMEM supplemented with 10% FBS and 1% penicillin/streptomycin at 37°C. For serum starvation, cells were washed three times with pre-warmed DMEM medium and then incubated in DMEM medium for 18 hours. In some experiments, 50 μM hydroxychloroquine (CQ, Sigma) was present in serum-deprived and control cells to block the fusion of lysosomes with autophagosomes. For amino acid and serum starvation, cells were washed three times with pre-warmed Hank's buffered saline solution (HBSS) and then incubated in HBSS for 1 hour. After starvation, cells were re-supplemented with complete medium for 1 hour before harvest.

Immortalized HdhQ111 mutant striatal cell lines and HdhQ7 wt cells were obtained from the CHDI Foundation. Cells were cultured in DMEM supplemented with 10% FBS, 100 mg/ml penicillin, 100 mg/ml streptomycin, and 400 mg/ml G418. Cells were grown at 33°C in a 5% CO2 incubator. Cells within 14 passages were used in all experiments.
HD patient fibroblasts (HD1: GM04693, HD2: GM21756, purchased from Coriell Institute, USA) and normal fibroblasts (Con 1, fibroblasts from adult, HDFa; Con 2, fibroblasts from juvenile, HDFn; purchased from Sigma-Aldrich) were maintained in MEM supplemented with 15% (vol/vol) FBS and 1% (vol/vol) penicillin/streptomycin. All of the above cells were maintained at 37°C in 5% CO2–95% air.