Fig. 4.

Phagocytosis of apoptotic RMA cells by mesangial cells from wild-type (n = 4) and C1q-deficient mice (n = 4). Graph showing the percentage of phagocytosis after 3 h of co-culture in the presence of 20% serum from wild-type animals or C1q- or C3-deficient mice and in the absence of serum. The results are expressed as a mean percentage of the phagocytic signal in the well containing wild-type serum for each experiment ± s.e.m. The control well was standardized to 100%. No inhibition in phagocytosis was detected using complement-deficient sera, while the absence of serum reduced the uptake to about 5–7% of the control. No difference of phagocytic uptake was observed between mesangial cells isolated from C1q-deficient or wild-type mice. ▪, Wild-type serum; , C1q-deficient serum; , C3-deficient serum; □, no serum.