pMHC/scFv fusion protein mediates killing of tumor cells by viral specific cytotoxic T cells

VernacularTitle:病毒肽/HLA-A2与单链抗体融合蛋白介导病毒特异性CTL杀伤肿瘤细胞
Author: Jianan LI ; Qian YU ; Xiongwen WU
Publication Type:Journal Article
Keywords: Viral peptide/HLA-A2 complex; CD71 single chain antibody; Fusion protein; Tumor cell
From: Chinese Journal of Microbiology and Immunology 2011;31(2):162-167
CountryChina
Language:Chinese
Abstract: Objective To study whether the HBC-A2/scFv fusion protein mediates killing of tumor cells by viral specific cytotoxic T cells. Methods The fusion protein was attached to the CD71-expressing, HLA class Ⅰ negative tumor cells. And then, cytolysis by viral peptide-specific CTLs which were generated by co-culture of peripheral blood lymphocytes from HLA-A2 positive donors with inactivated T2 cells pulsed with the viral peptide were tested by lactate dehydrogenase (LDH) releasing. Results The fusion protein can attach the active viral peptide/HLA-A2 complex to K562, HepG2 and U937 cells through binding of CD71 scFv to CD71 (37.30% ±8.25%, 27.20% ±3.88%, 21.80% ±6.49% ) and mediate cytotoxicity of viral peptide-specific CTLs against those cells in vitro ( K562: 42.08% ± 1.14% vs 8.07%± 1.39%; HepG2: 49.72% ± 1.59% vs 12.46% ± 1.26%; U937: 39.72% ± 3.26% vs 7.13% ±1.48% ). Conclusion This viral peptide/HLA-A2 complex targeted by CD71 scFv is able to redirect viral peptide-specific T-cell mediated immune responses against tumor cells.