RESUMEN
AIM: The aim of the present study is to explore the effects and mechanisms of HIV-1 glycoprotein gp120 on calcium-influx and ERK-phosphorylation of human microglia.METHODS: The level of intracellular calcium of human microglia grown on coverslip,which was loaded by calcium-probe,Fluo-4,and then treated in various experimental processing,was detected by confocal microscopy with time resolution mode.The binding of gp120 to human microglia was determined with confocal microscopy or flow cytometry after treatment with gp120 and stained with anti-gp120-FITC antibody.Phosphorylation of ERK within human microglia with or without gp120 stimulation was analyzed with confocal microscopy following the direct immuno-staining with anti-phosphorylated ERK antibody.RESULTS: The results of confocal microscopy showed that calcium-influx response was triggered by HIV-1 glycoprotein gp120 in human microglia.The results from analysis by confocal microscopy and flow cytometry showed that gp120 was able to bind to human microglia.ERK phosphorylation was enhanced in human microglia stimulated with gp120.CONCLUSION: HIV-1 glycoprotein gp120 induces calcium-influx in human microglia and enhances ERK phosphorylation in human microglia,indicating that gp120 is an activator of human microglia.So gp120 may be involved in the pathogenesis of HIV-associated dementia.