Targeting PD-1 and PD-L1


  • PD-1 (programmed cell death-1) is a cell surface protein involved in downregulating T-cell response, preventing autoimmunity under normal conditions.
  • PD-1 is typically expressed on T cells and has two ligands, PD-L1 and PD-L2. Interactions between PD-1 and PD-L1 result in T-cell downregulation, impairment, exhaustion, and apoptosis, all of which lead to immune evasion. By hyperexpressing PD-L1, certain cancers can thwart the host immune system.
  • There are multiple monoclonal antibodies used to disrupt the PD-1/PD-L1 interaction. Blocking either PD-1 or PD-L1 leads to immune recognition, infiltration, and cell-mediated apoptosis of cancer cells.
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