Through multiplexing of the miRNA scaffold to include multiple additional targets within a single CAR vector, we may knock down other molecules that are important in driving immune rejection (e.g., major histocompatibility complex class [MHC] I or II) or those involved in the immunosuppressive tumor microenvironment (e.g., PD-1, CTLA-4, LAG-3, TIM-3, and TIGIT) that also contribute to inhibit T-cell proliferation and activity, thus allowing for enhanced persistence [31]. The gene discussed is PDCD1; the disease is neoplasm.