Optiview hq universal linker

Immunohistochemistry was conducted on 4 µm thick formalin-fixed, paraffin-embedded (FFPE) tissue sections mounted on StarFrost Advanced Adhesive slides (Engelbrecht, Kassel, Germany) followed by drying at 80°C for 15 min. Immunohistochemistry was performed on a BenchMark Ultra immunostainer (Ventana Medical Systems, Tucson, AZ, USA). Sections were stained with anti-IDH1-R132H antibody H09 (Dianova, Hamburg, Germany) as previously described [3] . ATRX immunohistochemistry was performed as previously described [19] . In brief, after deparaffinization, slides were pretreated at 95°C in Cell Conditioning 1 buffer (Ventana) for 90 minutes. The sections were incubated with primary antibody HPA001906 (Sigma-Aldrich, St. Louis, MO; USA) diluted 1:200 for 2 hours. Standard Ventana signal amplification was used. For BRAFV600E staining V600E-specific clone VE1 was used. After pretreatment with cell conditioner 1 (pH 8) for 64 min, sections were incubated with VE1 hybridoma supernatant (monoclonal, dilution 1:5) at 37°C for 32 min. Antibody incubation was followed by OptiView HQ Universal Linker for 12 min, incubation with OptiView HRP Multimer for 12 min, signal amplification including the Ventana OptiView Amplification Kit (Ventana, catalogue number 760-099).