Intravital molecular imaging reveals the restrained capacity of CTLs in the killing of tumor cells in the liver.

ABSTRACT: Cytotoxic T lymphocytes (CTLs) and their gene-engineered cells display great application prospects in tumor immunotherapy. The timing of CTL-induced molecular events in tumor cells is unclear, and we also unknow whether the killing efficiency of CTLs is restrained in the liver, an immunotolerant organ with a high tumor incidence. Methods: We used intravital imaging to dynamically monitor the fluorescence resonance energy transfer (FRET) signals of caspase-3 and calcium sensor in tumor cells after transferring CTLs into tumor-bearing mice. Results: Our data show that several CTLs attacked on one tumor cell, and on average each CTL killed 1.24 ± 0.11 tumor cells per day in the liver, which was much less efficient than that in the spleen (3.18 ± 0.26 tumor cells/CTL/day). The ki

SUBMITTER: Liu L 

PROVIDER: S-EPMC7681101 | biostudies-literature | 2021

REPOSITORIES: biostudies-literature