LILRB Antagonist

Polzastobart (JTX-8064) is a humanized IgG4 monoclonal antibody and LILRB2 (ILT4) antagonist. Polzastobart specifically binds to and antagonizes LILRB2, relieves ILT4-mediated myeloid immunosuppression, and promotes the polarization of macrophages from an M2-like phenotype to an M1-like phenotype. Polzastobart induces macrophage polarization, IFNγ signaling, and T cell inflammation-related pharmacodynamic responses in ex vivo human renal cancer, lung cancer, and head and neck cancer tissues. Polzastobart can be used in studies related to tumor-associated macrophages and tumor immunity. For the isotype control of Polzastobart, refer to: Human IgG4 (S228P) kappa, Isotype Control (HY-P99003).

ES009 is a high-affinity LILRB2 antagonist, with IC₅₀ values of 14.07 nM and 18.61 nM for inhibiting hLILRB2-huANGPTL3 and hLILRB2-huANGPTL4, respectively. ES009 specifically blocks the interactions between LILRB2 and MHC class I as well as non-MHC ligands, thereby effectively inhibiting receptor activation. ES009 can reprogram anti-inflammatory myeloid cells and induce their conversion to a pro-inflammatory phenotype, and also reverse the T cell suppression mediated by macrophages. When combined with anti-PD-1 blockade therapy, ES009 synergistically enhances T cell activation. ES009 can be used in research related to advanced solid tumors and ovarian cancer.