Culture of human tumor infiltrating lymphocytes in hollow fiber bioreactors

Human tumor infiltrating lymphocytes (TIL) from metastatic melanoma of six patients were grown using a new hollow fiber bioreactor system. After inoculating 0.35-10 × 10⁸ TIL into the extra-fiber space (EFS), each Cellmax bioreactor was perfused with AIM-V medium, supplemented with rIL-2. The cells subsequently expanded 124-1170-fold to yield 1.5-5.4 × 10¹⁰ TIL over a 14-32 day period. TIL were flushed from the EFS using 200 ml medium and possessed an average viability = 91%. The phenotype and the autologous tumor cell lytic capacity of these TIL were similar to those of TIL grown in the currently used gas-permeable culture bags. Tissue culture media use averaged 4.3 liters/10¹⁰ TIL harvested. The TIL of one patient were re-expanded twice from cells remaining within the same bioreactor after harvest suggesting that one bioreactor cartridge could be used for repetitive, periodic studies. An estimated 80% decrease in technical time expended and in incubator space requirements were realized using this methodology. Cell culture on hollow fibers appears to be a useful method for producing large quantities of primary human lymphocytes for experimental, and perhaps, therapeutic needs.