CD28 and neoplasm: Additional technical issues need to be taken into account (i): pre-stimulation of tumor organoids with interferon γ (IFNγ) may be needed to enhance antigen presentation (ii), pre-stimulation of T cells with anti-CD28 and interleukin-2 (IL-2) may be required to support proliferation and expression of anti-Programmed cell death 1 (anti-PD1) thereby counteracting Programmed cell death ligand 1 (PDL1) inhibitory effects on tumor cells (107).