HLA-C and neuroblastoma: First, we surveyed the landscape of peptides accessible to T cells by performing MHC capture, peptide elution and liquid chromatography with tandem mass spectrometry17 (immunopeptidomics) on eight neuroblastoma cell-derived xenografts (CDX) and patient-derived xenografts (PDX) showing a wide range of MHC expression and also encompassing the array of rare recurring mutations found in high-risk neuroblastoma18,19 (Fig. 1a, Extended Data Table 1a).