EBV latent membrane protein 1 augments γδ T cell cytotoxicity against nasopharyngeal carcinoma by induction of butyrophilin molecules
Yue Liu, Ka Sin Lui, Zuodong Ye, Tsz Yan Fung, Luo Chen, Ping Yiu Sit, Chin Yu Leung, Nai Ki Mak, Ka‐Leung Wong, Hong Lok Lung, Yoshimasa Tanaka, Allen Ka Loon Cheung
Abstract
Nasopharyngeal carcinoma (NPC) is a diverse cancer with no well-defined tumor antigen, associated with oncogenic Epstein-Barr Virus (EBV), and with usually late-stage diagnosis and survival <40%. Current radiotherapy and chemotherapy have low effectiveness and cause adverse effects, which calls for the need of new therapy. In this regard, adoptive immunotherapy using T cells has potential, but needs to be coupled with butyrophilin 2A1 and 3A1 protein expression to achieve tumoricidal effect. Methods: Human T cells were expanded (with Zol or PTA) and used for cytotoxicity assay against NPC cells, which were treated with the EBV EBNA1-targeting peptide (L2)P4. Effect of (L2)P4 on BTN2A1/BTN3A1 expression in NPC cells was examined by flow cytometry and Western blot. An NPC-bearing NSG mice model was established to test the effectiveness of P4 and adoptive T cells. Immunofluorescence was performed on NPC tissue sections to examine the presence of T cells and expression of BTN2A1 and BTN3A1. EBV gene expression post-(L2)P4 treatment was assessed by qRT-PCR, and the relationship of LMP1, NLRC5 and BTN2A1/BTN3A1 was examined by transfection, reporter assay, Western blot, and inhibition experiments.