Figure 2

Decreased phagocytosis of apoptotic neutrophils in the presence of JSLE serum. Healthy adult control macrophages were incubated with pHrodo stained apoptotic neutrophils in a 10% JSLE, JIA or healthy paediatric control serum environment (n = 6). Macrophages not supplemented with serum were used as a base line control and had the lowest phagocytosis index (phagocytosis index = number of macrophages containing apoptotic material divided by the total number macrophages in the image, averaged across the four areas imaged by confocal microscopy.) Macrophages in JSLE sera had significantly less phagocytic capacity to engulf apoptotic neutrophils compared to those in the control sera group and JIA serum; p = 0.03 (A). Panel B shows a series of merged DAPI (blue), pHrodo (red) and Bright field images, from a single representative experiment. Increased red fluorescence in the control and JIA images indicates increased phagocytosis of apoptotic neutrophils compared to JSLE serum. Panel C represents a phagocytosis assay using JSLE macrophages incubated with 10% JSLE, JIA or control serum. There is a marked decreased in the amount of red fluorescence in the macrophages incubated with 10% JSLE serum compared to controls indicating less phagocytosis of apoptotic neutrophils by these cells, the % of phagocytosis in each serum is shown in D; n = 3.