Characterising TIL Products with ImmuneWatch DETECT: From Black Box to TCR-specificity Annotated Therapy

Tumor-Infiltrating Lymphocyte (TIL) therapy has demonstrated impressive clinical results in melanoma and is increasingly explored across solid tumors. Yet despite this promise, the final cellular product remains poorly characterised: expanded TIL infusions contain a mixture of tumor-reactive T-cells alongside viral bystander T-cells that offer no therapeutic benefit and may dilute efficacy.

Fully characterising the TIL product — knowing exactly which clones are tumor-reactive, what antigens they recognise, and which are off-target — is a critical step toward safer, more potent cell therapies.

In this interactive demo, we walk through how ImmuneWatch DETECT transforms TIL product characterisation from a black box into a fully annotated therapeutic. Starting from TCR repertoire sequencing data, DETECT clusters T-cell clonotypes and identifies a MelanA-specific cluster within the TIL product. These predictions are then validated experimentally, and the remaining repertoire is screened for viral bystander T-cells reactive to common pathogens.

Key capabilities demonstrated:

• TCR repertoire analysis of the expanded TIL product
• Unsupervised clustering of clonotypes by predicted antigen specificity
• Annotation of tumor-reactive clones, including MelanA-specific T-cells confirmed in the lab
• Bystander T-cell screening to flag off-target, virus-reactive clones

This use case is directly relevant to TIL therapy developers, cell therapy manufacturers, and translational immunologists seeking to move beyond bulk phenotyping toward deep molecular characterisation of their products.