ML-T7, a powerful inhibitor of Tim-3, effectively disrupts its interactions with PtdSer and CEACAM1. This compound enhances the antitumor activity of adoptive transfer therapy involving cytotoxic T lymphocytes (CTLs) and CAR T cells, while also boosting T cell effector functions. Additionally, ML-T7 augments the killing activity of NK cells against tumor cells and improves the antigen-presenting capacity of dendritic cells (DCs). Demonstrating antitumor efficacy in preclinical models, ML-T7 shows potential either as a standalone treatment or in combination with Nivolumab for tumor immunotherapy research [1].

ML-T7 (10 μM, 0-6 days) enhances the TCR/STAT5 signaling pathway via Tim-3, thereby promoting the anti-tumor activity of CD8+ cells [1]. When applied at 10 μM for 24 hours, ML-T7 facilitates the maturation and function of dendritic cells (DCs) through Tim-3 and Tim-4, boosting their antigen-presenting capabilities [1]. Additionally, ML-T7 (10 μM, 24 h) enhances cytotoxic T lymphocyte (CTL) activation and cytokine production, while reducing CTL apoptosis [1]. At a concentration of 10 μM for 48 hours, ML-T7 significantly increases the production of IFN-γ, TNF-α, CD107a, and granzyme B in the human NK cell line NK92 [1]. Western blot analysis in CD8+ cells at 10 μM for 0-6 days showed increased phosphorylation of phospholipase C–γ1 (PLC-γ1), ZAP70, LCK, ERK1/2, and STAT5 in response to anti-CD3/CD28 stimulation. In a cell invasion assay using bone marrow cells and a 10 μM concentration for 24 hours, ML-T7 elevated the expression of DC maturation markers.

ML-T7, administered intraperitoneally at 10-50 mg/kg every two days for 10 doses, has been shown to inhibit tumor growth and extend the survival of mice without adverse effects on mouse body weight. At a dose of 20 mg/kg, in combination with Nivolumab, ML-T7 enhances the antitumor activity of Nivolumab and significantly improves the survival rate in HCC mice. Additionally, ML-T7 at 50 mg/kg every two days for three weeks demonstrates good safety in mice. In 10-week-old mice with spontaneous orthotopic HCC, treatment leads to increased CD8+ T cells in tumors and spleen, reduction of T cell exhaustion, and improved function of CTLs, NK cells, and DCs. Furthermore, in 10-week-old mice with orthotopic Akt/c-Myc HCC, ML-T7 at 20 mg/kg exhibits enhanced antitumor activity alongside Nivolumab, rejuvenates NK cells, and inhibits the accumulation of MDSCs and Tregs.