The Total SHP1 cellular assay monitors the expression level of SHP1, and can be used as a normalization assay with our phospho-SHP1 Y564 kit. Because these phospho and total SHP1 assays are compatible, the two kits can be used in parallel on the same lysates.

Many cancer cells overexpress checkpoint inhibitor ligands such as PD-L1. PD-L1 binds its counterpart checkpoint inhibitor receptor PD1, present at the surface of T lymphocytes. In turn, the PD1-PDL1 complex recruits and activates inhibitory effectors, such as SHP1 or SHP2. These two phosphatases, which are phosphorylated on Tyr564 and Tyr542 respectively by the kinase Lck, trigger the dephosphorylation of signaling proteins such as ZAP-70 or SLP-76, involved in the T cell activation pathway. Finally, activated SHP1 and SHP2 participate in T cell inactivation.

Preventing the activation of SHP1 and/or SHP2 by small molecule inhibitors is believed to contribute to restoring the immune response against tumors.