anti-LLT1 monoclonal antibody ZM008

A human immunoglobulin G1 (IgG1) monoclonal antibody directed against the tumor-associated antigen (TAA) lectin-like transcript-1 (LLT1; CLEC2D; OCIL), with potential immunomodulating and antineoplastic activities. Upon administration, anti-LLT1 monoclonal antibody ZM008 targets and binds to LLT1 expressed on a variety of tumor cells. This prevents the binding of LLT1 to its receptor C-type lectin-like receptor cluster of differentiation 161 (CD161) primarily expressed on CD161-positive natural killer (NK) cells. This prevents CD161-mediated signaling, abrogates the CLEC2D/CD161-mediated suppression of NK cells, leading to the activation and infiltration of NK cells and cytotoxic T cells in the tumor microenvironment (TME) and promotes anti-tumor immune response, thereby enhancing cytotoxicity towards tumor cells. CD161, an inhibitory immune checkpoint, is broadly expressed on NK and a subset of memory CD4+ and CD8+ T cells. LLT1 is expressed on the surface of both malignant cells and various immune cells, including activated B-cells and myeloid cells. The interaction between LLT1 and CD161 leads to immune repressive condition in the TME allowing tumor cells to bypass the human immune system.