Lower apoptosis rate and higher CD69 expression in neutrophils from atopic individuals

Abstract.

Objective: In this study we aimed to examine the kinetics of CD69 expression and the susceptibility to apoptosis, in eosinophils and neutrophils, in the presence or absence of GM-CSF. We also addressed the question whether differences between atopic patients and healthy individuals exist in this respect.¶Materials and Methods: Freshly isolated eosinophils and neutrophils from non-atopic and atopic donors were analysed by flow cytometry for Annexin/PI staining, caspase 3 activation and CD69 expression.¶Results: We found a higher CD69 expression when atopic neutrophils were incubated with GM-CSF compared to non-atopic neutrophils, and that the kinetics of CD69-expression in neutrophils, but not in eosinophils, differed between non-atopic and atopic individuals (p < 0.004). We also found a higher viability in GM-CSF-stimulated neutrophils from non-atopic individuals as compared to neutrophils from atopic individuals (p < 0.05).¶Conclusion: These data suggest a potential role for neutrophils in the allergic inflammatory reaction through differences in apoptosis rates and CD69 expression between atopic and non-atopic individuals.¶