Tumour cells harness multiple resistance mechanisms to evade the host-tumour immune system. Notably, the programmed death 1 (PD1) receptor and its ligands, PD-L1 and PD-L2, play critical roles in T-cell suppression and exhaustion. Overexpression of PD-L1 and PD1 on tumour cells and tumour-infiltrating lymphocytes . . .
The World Health Organization (WHO) finally announces that COVID-19 is no longer a Health Emergency.