Extended Data Fig. 4: Characterization of tumour expression markers and HLA class I and class II in GBM. | Nature

Extended Data Fig. 4: Characterization of tumour expression markers and HLA class I and class II in GBM.

From: Neoantigen vaccine generates intratumoral T cell responses in phase Ib glioblastoma trial

Extended Data Fig. 4

a, The GBM tumour cell line from patient 7 that was established from the initial resection is positive for GBM tumour markers by immunohistochemistry. b, The GBM tumour cell line generated from initial resection tissue of patient 7 has low HLA-class I expression that is upregulated by IFNγ treatment and is negative for HLA-class II DR expression. This experiment was repeated four times. c, Immunohistochemistry analysis of HLA-class I and II expression on diagnostic sections of GBM tumours from the eight patients enrolled and vaccinated in the study. Semi-quantitative scoring was performed for the intensity of positive staining of tumour cell membranes or cytoplasm for class I or II (0, negative; 1, weak; 2, moderate; 3, strong) and for the percentage of positive staining malignant cells (0–100%). A cumulative H score was obtained by multiplying intensity score by the percentage of malignant cells with positive staining. This experiment was performed once, with the available resection tissue. d, Neoantigen-specific CD8+ T cells generated by vaccination of patient 7 do not recognize the GBM tumour cell line generated from initial resection tissue of patient 7 by TNF ELISPOT assay with or without IFNγ treatment to upregulate HLA-class I expression on tumour cells. Data were generated from one experiment with three replicate wells. Additional direct tumour recognition assays performed with IFNγ ELISPOT demonstrated similar results (data not shown). e, IFNγ secretion by the neoantigen-specific CD4+ T cell line generated from PBMCs of patient 7 against autologous dendritic cells (DCs) co-cultured with irradiated autologous GBM. Class II blocking antibody (ab) attenuated the IFNγ response. All T cell lines originated from week 16 PBMCs; ELISPOT experiments were performed in triplicate wells per time point.