The white blood cells of a cancer patient which have been:
- Taken from that patient’s tumor (where those white blood cells had been attempting to combat the cancer, albeit unsuccessfully)
- Stimulated with doses of interleukin-2 (to make the lymphocytes more effective against the cancer)
- Multiplied in vitro (i.e., outside of the patient’s body) to make them more numerous (and thus more likely to successfully combat the cancer).
When these “souped up” lymphocytes (white blood cells) are reintroduced into that same patient’s body, the lymphocytes (now called TIL cells because they have been “souped up”) attack the cancer tumor (malignant growth) more vigorously than before.
Lymphocytes found in solid tumors (e.g., lung cancers, melanomas, and renal cell carcinomas). Tumor-infiltrating lymphocytes include helper T cells and cytotoxic T cells; they participate in tumor recognition and, in some cases, tumor destruction.