Optimization and validation of processes related to the GMP compliant manufacture of genetically modified CAR expressing NK-92 cells

Emerging evidences show immunotherapy by enhancing our own immune system has become an attractive approach for cancer treatment due to the rapid drug resistance of chemotherapy. Fusion cytokines derived from GM-CSF and common g-chain interleukins have potent gain-of-function properties to alter host immune response.Wehave previously demonstrated that coupling ofGM-CSF at the N-terminus of common g-chain interleukins leads to meaningful gain-of function activity in interleukin-responsive lymphomyeloid cells. Recently, wehave generated a newly bioengineered fusokine GIFT4 that is derived from GM-CSF and IL-4. Here we tested the bioactivity of the novel fusion cytokine GIFT4 as a potential immunotherapeutic agent against caner. We observed that GIFT4 directly elicits anti-tumor adaptive B-cell immune response and consequent T cell immunity in vitro and in vivo. Murine GIFT4 expression suppresses melanoma tumor growth in immunologically intact mouse and administration of GIFT4 protein inhibits murine melanoma growth in vivo. GIFT4-B cell primed cytotoxic T cells frommelanoma patients specifically kill humanmelanoma cells in vitro and in immunedeficientNSGmice.Thus,GIFT4defines a novel engineered cytokine that mediates endogenous expansion of B-cells with potent anti-tumor effector function. We propose that GIFT4 protein could serve as a novel immunotherapeutic agent and defines a previously unrecognized potential of B-cells for personalized cancer cell immunotherapy. We expect that GIFT4 as an anti-melanomaagentwill provideanovel strategyandopens anewavenue forhumanBcellbased immunotherapy against melanoma. We propose that GIFT4-B cells could serve as a potent immunotherapeutic agent and define a previously unrecognized potential of B-cells for personalized cancer cell immunotherapy.