Determination of human γδ T cell-mediated cytotoxicity using a non-radioactive assay system.
The adoptive transfer of immune effector cells, such as CD8+ killer αβ T cells, γδ T cells, NK (natural killer) cells, and genetically-modified T cells, has been receiving increasing attention. It is essential to determine cellular cytotoxicity so as to monitor the function and quality of ex vivo-expanded immune effector cells before infusion. The most common method is the [51Cr]-sodium chromate release assay. It is, however, preferable to avoid the use of radioactive materials in clinical laboratories. In order to establish a non-radioactive alternative to the standard radioactive assay, we previously synthesized a chelate-forming prodrug (BM-HT) and demonstrated that a combination of BM-HT and europium (Eu3+) was useful to determine NK cell-mediated cytotoxicity. In the present study, we examined whether or not this improved assay system could be used to determine the cellular cytotoxicity exhibited by Vγ2Vδ2+ γδ T cells. In addition, we compared Eu3+ and terbium (Tb3+) in the measurement of cellular cytotoxicity. Our assay system using BM-HT could be used successfully for the analysis of both γδ T cell receptor (TCR)- and CD16-mediated cytotoxicity. When the intensity of fluorescence was compared between Eu3+ and Tb3+, Tb3+ chelate was more sensitive than Eu3+ chelate, suggesting that the detection system using Tb3+ is superior to Eu3+ when tumor cells are not efficiently labeled with BM-HT. The method established herein is expected to promote the development of novel adoptive cell therapies for cancer.
['Tagod|Mohammed S O|MSO|', 'Mizuta|Satoshi|S|', 'Sakai|Yuki|Y|', 'Iwasaki|Masashi|M|', 'Shiraishi|Kengo|K|', 'Senju|Hiroaki|H|', 'Mukae|Hiroshi|H|', 'Morita|Craig T|CT|', 'Tanaka|Yoshimasa|Y|']
D018414:CD8-Positive T-Lymphocytes D045744:Cell Line, Tumor D003602:Cytotoxicity, Immunologic D005063:Europium D006801:Humans D007694:Killer Cells, Natural D016692:Receptors, Antigen, T-Cell, gamma-delta D013725:Terbium
γδ T cells Europium Terbium Nitrogen-containing bisphosphonate Non-radioactive cellular cytotoxicity assay Terpyridine