CD4 and neoplasm: While Beatty et al. demonstrated that the depletion of Treg cells in the peripheral blood did not affect the Treg cell frequency in the tumour lesion and had no effect on tumour progression, a CD40 agonist used in combination with Gem decreased the Treg cell numbers and the accumulation of CD4+ and/or CD8+ cells in xenograft and/or orthotopic tumours [110], indicating that Gem, which can deplete tumour-infiltrating Treg cells, may restore the antitumour effects of CD40 agonists and ICIs.