Fig. 3. Linear RGD-peptides reduce the percentage of phagocytic active cells in vitro. (Ai) Photograph of an isolated endoneurial phagocyte cultured in the presence of monodispersed polystyrene carboxylated Fluoresbrite YG microspheres. (Aii) Photomicrograph showing the large number of fluorescent microspheres engulfed by the phagocyte shown in Ai. (Bi) Percentage of spreading cells that internalized uncoated microspheres when cultured in ABS only, ABS + 100 µmol l^–1 SDGRG and ABS + 100 µmol l^–1 GRGDS. (Bii) The distribution of the number of uncoated microspheres engulfed by spreading cells under the three culture conditions. Note that the addition of GRGDS had no effect on the percentage of phagocytic cells engulfing uncoated microspheres nor on the distribution of the number of engulfed uncoated microspheres. (Ci) Percentage of spreading cells that phagocytized fibronectin-coated microspheres when cultured in ABS only, ABS + 100 µmol l^–1 SDGRG and ABS + 100 µmol l^–1 GRGDS. The addition of GRGDS significantly reduced the percentage of phagocytic cells. (Cii) Distribution of the number of engulfed fibronectin-coated microspheres by spreading cells is shifted to the right (i.e. more microspheres are engulfed) when the cells were cultured in ABS or ABS + 100 µmol l^–1 SDGRG. In contrast, treatment with GRGDS did not result in a similar increase in internalization of fibronectin-coated microspheres. Scale bar in A, 10 µm. ^***P<0.001.