Improving lung cancer tumor-infiltrating lymphocyte (TIL) manufacturing

Abstract

Background: The successful treatment of melanoma using autologous in vitro expanded tumor infiltrating lymphocytes (TILs) has sparked clinical trials for the assessment of TIL efficacy against other cancers, including non-small cell lung cancer (NSCLC). This rise in clinical applications of TILs has increased the need for improved, more streamlined and cost-effective manufacturing protocols. The aim of this study was to simplify and reduce the cost of traditional TIL manufacturing protocols while maintaining GMP manufacturing compliance, yields, and quality of the TIL product.

Methods: Resected lung tumors were cultured to expand TILs. In side-by-side experiments, we evaluated media formulations, supplementing reagents, reagent concentrations, TIL activation methods and cryopreservation protocols. The optimizations aim to reduce labor, reagent cost, culture times, and open step manipulations. The resulting TIL products were compared against TILs produced using the Moffitt Cancer Center published protocol. We compared cell yields, viabilities, phenotypes, and TIL cytotoxic activity against matched tumor organoids.

Results: TILs were successfully expanded from 35 fragmented tumor samples using T-cell specific media in place of RPMI, human AB serum in place of human platelet lysate and α-CD3/CD28 nanobeads in place of feeder cells for cell activation. Culture duration was reduced from 6 to 7 weeks to 4 weeks and the final product contained an average of 200e9 TILs that were predominantly of the memory phenotype and effectively killed matched tumor cells. While TIL yields and phenotypes were comparable to those produced by the Moffitt Cancer Center protocol, cytotoxicity against matched tumor cells was superior.

Conclusion: Traditional TIL manufacturing protocols could be optimized and streamlined into a more cost-effective process for a TIL product that is cytotoxic to tumor cells and yields quantities suitable for clinical studies.

Keywords: GMP manufacturing; cell therapy; non-small cell lung cancer; tumor-infiltrating lymphocyte.