NKG2D和NKG2A及相应配体MHC-IA/B和HLA-E在急性白血病的表达及意义

Expression of NKG2D and NKG2A with Their Ligands MHC-I A/B and HLA-E in Acute Leukemia Patients and Its Significance

本研究旨在初步探讨NK细胞受体NKG2D和NKG2A在初发ALL和AML患者NK细胞、CD3+T细胞的表达其及相应配体MHC-I A/B和HLA-E在白血病细胞表达差异性和免疫学意义。用流式细胞术检测NK92细胞对8种白血病细胞系的杀伤效率,并检测60例初发急性白血病患者(ALL和AML各30例)骨髓中NKG2D和NKG2A在NK和CD3+T细胞的表达及其相应配体MHC-I A/B和HLA-E在白血病细胞的表达。结果表明,NK92对不同白血病细胞系的杀伤效率存在差异。ALL患者NK细胞和CD3+T细胞的NKG2D及NKG2A阳性表达率与AML患者相比均无显著差异(p>0.05),但是ALL患者白血病细胞MHC-I A/B和HLA-E阳性表达率均明显高于AML患者(p<0.05)。结论:ALL与AML患者免疫细胞功能的差异性可能与白血病细胞配体表达的不同有关,而与本身NK及T细胞表达的杀伤和抑制性受体无关。

This study was aimed to explore the difference of NK cell receptor NKG2D and NKG2A expression on NK cells and CD3＋T cells and their ligand MHC-I A/B（major histocompatibility complex class I-related chains A/B）and HLA-E expression in leukemia cells,as well as its immunological significance.Flow cytometry was used to detect the killing rate of NK92 cells to 8 leukemia cell lines,and the expression of NKG2D and NKG2A on NK cells and CD3＋T cells as well as their ligand MHC-I A/B and HLA-E expression on leukemia cells.The results indicated that the NK92 showed different killing activity to different leukemia cell lines.The positive expression rate of NKG2D and NKG2A on NK cells and CD3＋T cells in ALL patients was no significantly different from that in AML patients（p〉0.05）,but positive expression rate of MHC-I A/B and HLA-E in ALL patients was obviously higher than that in AML patients（p〈0.05）.It is concluded that there is difference of immune cell function between ALL and AML patients,this difference may be associated with the expression difference of NKG2D and NKG2A ligands on leukemia cells while does not associated with the killing and inhibiting receptors expressed on NK cells and CD3＋ T cells.