Fig. 1

Effects of anti-CCP and RF positivity on phagocytosis of non-opsonized yeast cells by neutrophils from RA patients. Data are expressed as medians, quartiles and extreme values. RA caused a rise in the phagocytosis of non-opsonized yeast (p < 0.0001; t test with Welch’s correction) and anti-CCP-positive and RF-positive individuals displayed a higher phagocytic index. This increase was due to an increase in the percent of neutrophils engaged in phagocytosis, but no difference was observed in the number of yeast ingested between anti-CCP- or RF-negative or -positive individuals (p > 0.05). Top: neutrophil phagocytic index (a, b, c); Middle: average number of S. cerevisiae yeast cells ingested by phagocytosing neutrophil  (d, e, f); Bottom: percent of neutrophils engaged in phagocytosis (g, h, i). The statistical differences are marked in the graphics and in text