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Is the MOA due to Leronlimab elevating PD-L1 expression so that the presence of cancer can be identified and then treated? Or, is the MOA still unknown until they know why Leronlimab elevates the PD-L1 expression?

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A cold tumor has low immune activation so few killer T-cells or macrophages to fight the tumor. Leronlimab highly activates the killer T-cells and macrophages turning the tumor hot. PD-L1 is expressed when the immune system is activated and it tries to balance out and lower the higher activation. It does this by trying to switch macrophages to an M2 (tumor cell protective) phase by increasing Tregs that protect tumors and signaling for the killer T-cells to not kill the tumor cell. So the PD-L1 when bound to its receptor PD-1 actually hides the tumor from destruction.

The increase in PD-L1 would be a direct response to leronlimab upregulating killer cells. But leronlimab also downregulates the chemokines most responsible for activating PD-L1. I'm still trying to figure out why maraviroc lowers PD-L1 and leronlimab raises it. Is the PD-L1 they are measuring not bound to its receptor PD-1. Is PD-1 upregulated alongside PD-L1. Lots of questions and no answers.