Effects of monocyte on anti-K562 cell activity of NK cell

ZHENG Meizhu; PAN Jingxin; PAN Hongda; GUO Jianxin

Abstract：To explore the diversify of reactive nitrogen metabolites (RNM)/ reactive oxygen metabolites (ROM) and their influence on anti-K562 cell activity of NK cell during the monocytes respiratory burst.In the co-cultivation system of NK cells and K562 cells, mono-cytes or/and IL-2/PHA were administered, then the corresponding changes of RNM/ROM and TNF-β /IFN-γ production, as well as K562 cell inhibition rate (KIR) were observed.Besides, histamine dihydrochloride (DHT) and tiopronin (TIP) were administered in the culture system and the indexes above were observed again.After IL-2/PHA was administered in the cultivated systems mixing with NK cells and K562 cells as the E/T (NK/K562) ratio was 10/1, KIR increased gradually; after monocytes being appended as E/MO (NK/monocyte) ratio was 10/2, 10/5, and 10/10, RNM and ROM productions increased correspondingly, but TNF-β /IFN-γ production and KIR decreased.Controlling by K562 cells, the negative correlation coefficient of RNM to KIR exceeds that of ROM to KIR.After administering DHT and TIP, expecially TIP, the ROM production decreased but the TNF-β/IFN-γ production and KIR increased.Morover, TIP could decrease the RNM production but DHT failed.All the results suggest that monocytes could product a lot of ROM and RNM to degreded NK cells ac-tivity and disable NK cells in killing K562 cells, in which RNM may play more important role than ROM; TIP can reverse the depressant ef-fect of MO on NK cell by scavenging ROM and RNM.