Panoply™ Human CD96 Over-expressing Stable Cell Line

The poliovirus receptor (PVR) and its receptor system, including TIGIT, CD226, and CD96, play a key role in regulating tumor immune escape. When CD96 binds to PVR on tumor cells, it inhibits the function of T cells and NK cells, thereby promoting tumor immune escape. Therefore, screening immune checkpoint inhibitors (ICIs) targeting the CD96/PVR pathway will provide promising candidate drugs for tumor immunotherapy. Here, researchers used MOE software to virtually screen small molecules from the FDA-approved drug library. The results showed that epinastine has a high affinity for CD96, thereby effectively blocking the interaction between CD96 and PVR. In vitro co-culture experiments further showed that epinastine can effectively restore the ability of Jurkat cells to secrete IL-2. In the MC38 tumor model, epinastine significantly enhanced the infiltration of T cells and NK cells into the tumor site and increased their secretion of IFN-γ, thereby effectively inhibiting tumor growth.

It has been reported that CD96 is located on immune cells and can exert an immunosuppressive effect after binding to its ligand PVR. Epinastine can bind to CD96 and block CD96/PVR binding at the protein level. To detect whether epinastine can bind to CD96 on the cell surface, the researchers performed a cellular thermal shift assay (CETSA), and the results showed that epinastine treatment significantly increased the thermal stability of CD96 (Figure 1A, B), indicating that epinastine targets CD96 on the cell surface. Therefore, they also conducted a co-culture experiment to explore the effect of epinastine on the recovery of immune cell function. First, a Jurkat-hCD96 cell line overexpressing human CD96 was established (Figure 1C). Subsequently, Jurkat-hCD96 was co-cultured with CHO-K1-hPVR cells. Epinastine significantly enhanced the IL-2 secretion of Jurkat-hCD96 cells, and its effect was comparable to that of anti-hCD96 antibodies (Figure 1D, E). The results highlight that epinastine can target CD96 on immune cells, thereby inhibiting the binding of CD96 to PVR and alleviating its immunosuppressive effects on immune cells. In summary, these results show that epinastine can target CD96 on immune cells, thereby inhibiting CD96/PVR binding and alleviating its immunosuppressive effects on immune cells.

Figure 1. Effects of Epinastine on immune cell activity in vitro. (Zhang X, et al., 2025)