TNF-alpha induced changes in cell membrane antigen expression on K-562 cells associated with increased lactate...

TNF-alpha is a pleiotropic cytokine, which induces death of sensitive cells, whose effect depend on cell membrane receptor expression, cell cycle phases, as well as on intracellular ratio of pro- apoptotic and anti-apoptotic molecule expression. Since determination of LDH release from cultured cells in vitro, reflects early membrane alterations, we estimated and compared LDH release from cultured cells with changes in cell membrane antigen expression on K-562 cells after TNF-alpha treatment by flow cytometry. The significant increase in LDH release activity and cytotoxicity values was associated with decrease in membrane molecule expression for CD45 and CD30 as well as for low expressed CD45RA and CD38 after TNF-alpha treatment. However, percentage of decrease of all examined molecules is not uniform, and appears to depend on the respective level of pre treatment values expression and molecule type. These results indicated the complexity of events on cell membrane, including association between increasing LDH release and decrease of antigen expression of membrane molecules following TNF-alpha mediated processes.