EFFECT OF THE DIFFERENT FUNGUS STIMULI ON THE EXPRESSION OF MEMBRANE RECEPTORS OF NATURAL KILLER CELLS

Objective To explore the effect of different stimuli and morphotypes of fungus(aspergillus fumigatus and candida albicans) on the expression of membrane receptors of natural killer(NK) cells derived from cord blood,and compare the differences of mechanism between anti-fungal and anti-tumor process induced by NK cells.Methods The experiments were divided into two groups: Transwell non-contact culture group(indirect-contact) and mixture culture group(direct-contact).The ratio between NK cells and fungus/K562 cells was 10:1.The expression of NKG2D,TLR2 and CD94/NKG2A were detected by flow cytometry after 6h of culture.Results The expression of TLR2 in fungus direct-contact group was significantly higher than that in control group(P<0.05),while the fungus indirect-contact culture had no impact on TLR2 expression(P>0.05).However,the expression levels of NKG2D and CD94/NKG2A in both fungus direct-contact and indirect-contact groups had no change(P>0.05).The expression of NKG2D was significantly higher in K562 cells direct-contact group than that in control group(P<0.05),while no differences of TLR2 and CD94/NKG2A expressions were found(P>0.05).Conclusions Fungus could activate NK cells by up-regulating the expression of TLR2,which is different in tumor cells.Neither fungus nor tumor cells have effect on the expression of CD94/NKG2A.