Activation and propagation of tumor-infiltrating lymphocytes from malignant pleural effusion and ascites with engineered cells for costimulatory enhancement

Adoptive cell therapy (ACT) of autologous tumor-infiltrating lymphocytes (TILs) has shown an effect on mediating tumor regression in some patients with highly advanced, refractory metastatic malignancy. Here, the in vitro generation of TILs isolated from malignant pleural effusion and ascites was compared with which using engineered cells for costimulatory enhancement (ECCE) and 3 common γ-chain cytokines, interleukin (IL)-2, IL-7, and IL-15, alone or in combination. We showed the robust clinical-scale production of TILs with a less differentiated 'young' phenotype by expansion in the presence of ECCE combined with IL-2/7/15. Furthermore, a major fraction of the TILs generated in this fashion was shown to produce much more IFN-γ and TNF-α, and displayed cytolytic activity against target cells expressing the relevant antigens. To our knowledge, this is the first time that the combination of ECCE and IL-2/7/15 has been applied for the generation of TILs isolated from malignant pleural effusion and ascites.