Fig. 4. PGCs from E7.25 extra-embryonic mesoderm. Intact extra-embryonic mesoderm fragment (A) and cells dissociated from a fragment (B,C) were cultured for 48 hours, and then stained for ALP activity (A,B) or for PGC7 (C). ALP-positive cells developed from the intact fragment (A) and from dissociated cells (B, arrowheads). ALP-positive cells in B also stained with the anti-PGC7 antibody (C, arrowheads). Scale bars, 160 µm (A) and 100 µm (B,C) µm.