Dendritic Cell

Dendritic cells fed with tumour cell lysates prime rare neoantigen-specific CD4 T cells and cross present antigen to prime neoantigen-specific naive CD8 T cells

Therapies targeting the modification of tumor cells to increase neoantigen expression and improve immune cell recognition are currently under development. Detecting these subtle changes typically involves several cycles of dendritic cell restimulation of T cells, followed by the sensitive measurement of rare neoantigen-specific T cell responses using IFNγ ELISPOT assays. The schematic below shows the assay design with multiple round of dendritic cell (DC) restimulation to expand rare neoantigen T cell responses.

IFNγ release from activated tumour neoantigen-specific CD4 T cells

IFNγ release from activated tumour neoantigen-specific naive CD8 T cells

Figures: CD4 or naïve CD8 T cells were co-cultured with unloaded dendritic cells (DC), or with DC loaded with tumour cells that had been previously treated with media or vehicle. Three rounds of stimulation of T cells with DC were performed (* single round of DC stimulation). PMA and ionomycin were added as positive controls during the final round of stimulation. T cell stimulation was assessed by measuring the number of spot forming units (SFU) by IFNγ ELISpot. Media and T cell only wells were included as background controls. Number of SFU per 100,000 plated T cells, with mean of two (experimental controls) or three (all others) replicates ± SEM shown. Representative images of CD4 and naïve CD8 T cell IFNγELISpot. Each blue dot represents one IFNγ-producing T cell. ULOD = Upper Limit of Detection