ABSTRACT
Objective: To analyze the expression of HLA class Ⅰ molecules and MHC classⅠ related chain A and B (MICA/MICB) in human nasopharyngeal carcinoma cell line (CNE2) and multi-drug resistant nasopharyngeal carcinoma cell line (CNE2/ DDP), and to assess their influence on NK cell-mediated lysis.Methods: Expression of HLA classⅠ molecules and MICA/MICB on the surface of CNE2 and CNE2/DDP cell lines was analyzed by flow cytometry. Cytotoxicity of NK cells (isolated from 3 healthy persons) against CNE2 and CNE2/DDP cells were detected by LDH releasing assay at different effect-to-target cell ratios (E∶T). In blocking experiments, anti-MHC class Ⅰ monoclonal antibody (mAb) (W6/32, a pan anti-HLA class Ⅰ antibody) and anti-MHC class I chain related molecules mAb (BAMO-1, specificly against MICA and MICB) were added to the target cells at a E∶T ratio of 10∶1. Results:It was found that the expression of HLA class Ⅰ molecules and MICA/MICB on CNE2 was higher than that on CNE2/DDP(P