Changes in blood from human research subjects. The concentrations of pGSN and IL-1β were measured in plasma samples and blood-borne MPs were quantified preexposure, at-exposure, and postexposure to 300 kPa as described in methods. Individual data points are shown and below each plot are means ± SE, n = 6 for each sample, * indicates significantly different from preexposure, P < 0.05, RM ANOVA. IL-1β, interleukin-1β; MP, microparticles; RM, repeated-measures; pGSN, plasma gelsolin.