Abstract 878P
Background
It is estimated that over a million new cases and half million deaths related to gynecological cancers annually worldwide. A recent ph2 trial reported that tumor-infiltrating lymphocyte (TIL) therapy can trigger significant tumor response in late-stage cervical cancer patients. However, for the rest of the gynecological cancer patients, the feasibility of TIL treatment has yet been fully explored. Here, we describe a method to cultivate clinical scaled TIL in multiple gynecological malignancies, including cervical cancer, ovarian cancer, endometrial cancer and vulvar cancer.
Methods
Cell culture: The process is segmented with two phases. In ph1, fresh tumor samples were collected and dissociated into smeared pads. The tumor sample was bulk cultured with 6,000 IU/ml of recombinant human IL2. Ph2 begins upon the cultured lymphocytes reaching to of 107. The cells will be transferred into a new container and resume culture with irradiated allogeneic PBMC, aCD3, and aPD-1 until the cell number gets to dose requirement. Phenotype assay: Final harvested TIL products were collected and assayed for identity by immunofluorescent staining. Percentage of T cells, NK cells and T cell subtypes were measured. Function assay: The T cell activation potential of the final TIL products are tested with PMA culture. TILs were cultured within the whole medium and 50ng/ml PMA for 4 hours before analyzing INFγ expression on T cells.
Results
Across different cancer types, the final TILs are more than 90% of T lymphocytes with a variable percentage of CD4/CD8 ratio. Despite the cancer type differences, there are less than 10% of Tregs expanded through the ex-vivo TIL culture while most of the TILs are effective memory T cells. A constant and noticeable CD56+/CD3+ NKT cell population exists within the TIL population across different cancer types. The results from PMA and CD3/CD28 stimulation assay prove the different genealogical TILs sustains an activation potential upon proper antigen recognition.
Conclusions
We have developed a mothed to successfully culture clinical-grade TILs from different types of gynecological malignancies. The method could potentially benefit the later clinical trials for TIL in gynecological malignancies.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
Sun-Yat-sen Memorial Hospital of Sun-Yat-sen University Grit Therapeutics, Inc.
Funding
Grit Therapeutics, Inc.
Disclosure
T. Yao, Y. Wang, Z. Lin, M. Chong: Research grant/Funding (institution): Grit Therapeutics, Inc. Z. Shi, Y. Liu: Full/Part-time employment: Grit Therapeutics, Inc.