Culturing Murine and Human NB Cell Lines

A GD₂-positive murine NB cell line NXS2 [18 (link)] and CHO cell line [19 (link)] (ATCC, Wesel, Germany) were cultured in Dulbecco's modified Eagle's medium supplemented with stable glutamine, 4.5 g/l glucose (DMEM; PAN-Biotech, Aidenbach, Germany), 10% (v/v) fetal calf serum (FCS), 100 U/ml penicillin and 0.1 mg/ml streptomycin (1× P/S; PAA, Pasching, Austria). Hybridoma cells producing murine anti-Id Ab ganglidiomab [17 (link)] were cultured in serum-free DMEM with stable glutamine and 4.5 g/l glucose supplemented with 1× non-essential amino acids (PAA, Pasching, Austria) and 50 μM β-mercaptoethanol (Sigma Aldrich, Steinheim, Germany). The human NB cell line LA-N-1 [20 (link)] was cultured in RPMI (PAN-Biotech, Aidenbach, Germany) supplemented with 4.5 g/l glucose, 2 mM stable glutamine (PAA, Pasching, Austria), 10% (v/v) FCS and 1× P/S. The genetically engineered NK-92-scFv(ch14.18)-zeta cell line (NK-92tr), expressing a GD₂-specific chimeric antigen receptor derived from ch14.18, was kindly provided by Prof. W. Wels (Georg-Speyer Haus, Frankfurt, Germany) and cultured as previously described [21 (link)].