Potent Cytotoxic Tumor-Infiltrating Lymphocytes Can Be Generated from Immune-Excluded Chondrosarcomas Using...

Area of Science:

• Immunology
• Oncology
• Biotechnology

Background:

• Autologous tumor-infiltrating lymphocyte (TIL) therapy is effective against "hot" tumors but faces challenges with "cold" tumors.
• Sarcomas, often "cold" and immune-excluded, present difficulties for TIL generation due to low lymphocyte infiltration and immune resistance mechanisms.
• Limited understanding of tumor microenvironment (TME) resistance hinders effective TIL therapy development for these cancers.

Purpose of the Study:

• To generate and expand tumor-infiltrating lymphocytes (TIL) engineered with regulatable, membrane-bound IL15 (cytoTIL15™) from immune-excluded chondrosarcoma.
• To assess the efficacy of these engineered TIL in overcoming immune resistance and tumor killing in vitro and in 3D models.
• To investigate the role of IL15 in enhancing T-cell receptor signaling and cytotoxicity in the context of chondrosarcoma TME.

Main Methods:

• Generation and expansion of TIL from chondrosarcoma biopsies engineered with membrane-bound IL15 (cytoTIL15™).
• Assessment of TIL tumoricidal capacity in cell culture and 3D tumor spheroid models without exogenous IL2.
• Spatial profiling of the tumor microenvironment (TME) to identify resistance mechanisms (collagen, myeloid infiltration) and lymphocyte distribution.
• Analysis of IL15's effect on T-cell receptor signaling thresholds and T-cell infiltration/cytotoxicity in autologous 3D models.

Main Results:

• Successful generation and expansion of cytoTIL15™ from immune-excluded chondrosarcoma, demonstrating potent tumor-killing capacity.
• Engineered TIL exhibited efficacy in cell culture and 3D models independent of exogenous IL2.
• Spatial profiling identified collagen and myeloid infiltration as key resistance factors, with lymphocytes restricted to tumor periphery.
• IL15 reduced T-cell receptor signaling thresholds, enhancing TIL infiltration and cytotoxicity in autologous 3D tumor models.

Conclusions:

• Engineered TIL with membrane-bound IL15 (cytoTIL15™) can be generated from immune-excluded chondrosarcoma, showing potent anti-tumor activity.
• This IL2-free approach demonstrates efficacy in overcoming TME resistance mechanisms like collagen and myeloid infiltration.
• The findings suggest a potential for developing IL2-free TIL therapy for patients with immune-excluded tumors, including sarcomas.