PDCD1 and neoplasm: For instance blocking inhibitory receptors KLRG1, PD1 and CTLA-4 on ILC1 population may help in increasing production of anti-tumour cytokines, IFN-γ and TNF-α, but as these receptors are also expressed highly on ILC2 population in tumour environments, using blocking agents might contribute to increase in type 2 cytokine production and modulate tumour growth.