Multifunctional T-cell analyses to study response and progression in adoptive cell transfer immunotherapy

Area of Science:

• Immunology
• Oncology
• Cellular Therapy

Background:

• Adoptive cell transfer (ACT) with T-cell receptors (TCR) engineered to target cancer antigens is a developing immunotherapy.
• Melanoma patients receiving TCR-engineered T cells targeting the MART-1 antigen were studied to assess in vivo T-cell activity.

Purpose of the Study:

• To investigate the in vivo functional activity and dynamics of adoptively transferred T cells in melanoma patients.
• To evaluate the relationship between T-cell functionality and antitumor response in ACT immunotherapy.

Main Methods:

• Analysis of secreted proteins from individual T cells and enumeration of T cells with TCR specificity for melanoma antigens.
• Longitudinal sampling from three melanoma patients undergoing ACT with MART-1-targeted TCR transgenic T cells.

Main Results:

• Coordinated functional dynamics were observed in both transferred and endogenous T cells.
• Highly functional T cells were found to be crucial for a dominant antitumor immune response.
• The study identified specific secreted proteins and T-cell populations involved in the immune response.

Conclusions:

• Longitudinal functional studies of TCR-engineered lymphocytes provide insights into the evolution of antitumor responses in advanced melanoma ACT.
• Maintaining T-cell functionality is critical for improving the long-term efficacy of TCR-engineered ACT immunotherapy.