Cellular Therapy: TIL Tomorrow and Further

Mark B. Faries, MD
Co-Director, Melanoma Research Program
The Angeles Clinic & Research Institute, A Cedars-Sinai Affiliate
Cellular Therapy: TIL Tomorrow and Further for melanoma.
Dr. Mark B. Faries is a renowned doctor and researcher in the field of melanoma. As the Co-Director of the Melanoma Research Program at The Angeles Clinic & Research Institute, a Cedars-Sinai affiliate, he has dedicated his career to finding new treatments for this deadly form of skin cancer.
TIL (tumor-infiltrating lymphocyte) therapy represents a groundbreaking approach in cellular immunotherapy, offering new hope in the fight against various cancers including head and neck squamous cell carcinoma, melanoma, lung cancer, genitourinary cancers, and an expanding roster of other malignancies. This innovative treatment harnesses the power of the patient’s immune system, utilizing specific components to target and eliminate cancer cells.
What exactly are TILs?
To understand how TIL therapy operates, it's important to first define TILs. As the name suggests, TILs are a type of lymphocyte, which are crucial immune cells produced in the bone marrow and present in the blood and lymphatic tissue. Lymphocytes are categorized into B lymphocytes, responsible for antibody production, and T lymphocytes, which play a key role in destroying tumor cells and regulating immune responses. TILs have the unique ability to travel from the bloodstream into tumors, where they can identify and obliterate cancer cells.
The Mechanism of TIL Therapy in Cancer Treatment
TIL therapy employs a novel strategy by using the tumor’s own cells as a weapon against it. The process begins with the extraction of TILs from tissue removed during surgical resection. These TILs are then cultivated in a laboratory setting to significantly increase their numbers using interleukin-2 (IL-2), a protein that encourages their rapid proliferation. This cultivation process can take approximately four to six weeks, necessitating that the patient's tumor remains stable during this period to be eligible for TIL therapy.
Once the TILs have been expanded to billions in number, they are reintroduced into the patient's bloodstream. Here, they actively seek out and attack cancer cells while sparing healthy tissue. Prior to TIL infusion, patients undergo a week of chemotherapy to prepare the body for the influx of TILs by creating room for their expansion.
A unique aspect of TIL therapy is its one-time application. Unlike many cancer treatments that require ongoing sessions, TIL therapy is typically administered just once. However, for patients who have previously responded well to TIL therapy and need further treatment, a second round of therapy may be considered.
TIL therapy exemplifies the remarkable advancements in cellular immunotherapy, offering a potent, targeted approach to cancer treatment that leverages the body’s own immune system to combat disease.