PD-1 /PD-L1 is adoptive checkpoint mechanism, where PD-1 is an adopting its PD-L1 ligand activities by presence of specific helical kinase proteins in its compositions: _gamma common chains,_LNK” lymphocyte adaptor protein, _or SH2B adaptor _protein “tyrosine kinases, and _”SOCS” suppressor of cytokine signaling, that specified for controlling PD-1 and PD-L1 bindings activity through temporary resting the PD-L1 and consequently T-cells activities then transform incoming signals to exogenous processes in favor the of proper immune functions, But the permanent inhibition of PD-1 /PD-L1 binding is due to breaking down or inhibition in one or more of the adaptors helical proteins (lymphocyte adaptor protein, or SH2B) with the presence of SOCS” suppressor of cytokine signaling that will increase stability of binding without adopting and without activities, but cells survival can still exist through presence of tyrosine kinases , interferon stimulate kinases ,and gamma common.