Human peripheral blood mononuclear cells were analysed for ATP-induced ethidium uptake using time-resolved flow cytometry. Monocytes were identified by an anti-CD14 APC antibody and T lymphocytes were identified by an anti-CD3-PE antibody. Ethidium uptake (25 μM) was measured in response to P2X7 receptor stimulation by 1mM ATP. (A) and (C) are representative ethidium uptake curves from genotyped individuals. (B) and (D) are scattergrams of collated data from 5 to 18 subjects from each genotype group (number of subjects shown in brackets) with ATP-induced ethidium uptake calculated from the slope of the linear portion of the uptake plot over 1 minute. *P < 0.05 from one-way analysis of variance with Dunnett's post hoc test.
Lester et al. Arthritis Research & Therapy 2013 15:R71 doi:10.1186/ar4248