Igf2 affects AGM hematopoiesis. (A) Venn diagrams showing the populations in which Igf2 and its receptors and binding proteins demonstrated differential expression. (Bi) Semiquantitative RT-PCR showing the expression of Igf2 and its receptors in several hematopoietic tissues of an E11 embryo and in the AGM-derived supportive stromal cell line UG26-1B6. (Bii) In situ hybridization on an E11 embryo section with a riboprobe specific to Igf2. Stained sections were mounted with Hydromount. DA indicates dorsal aorta; FL, fetal liver; M, myotome; and UGR, urogenital ridge. (Biii) Igf2 mRNA expression in the E11 dorsal aorta (ventral, down). Arrow highlights Igf2 expression in the intra-aortic cluster. Pictures were taken with a Zeiss AxioSkop2 Wide-Field Microscope fitted with a Zeiss AxioCam MRc5, and images analyzed with the Zeiss AxioVision software (all from Carl Zeiss Ltd). Objectives used were 5×/0.15 NA (ii) and 20×/0.45 NA (iii). (Ci) Outline of experiment to test the effect of Igf2 on colony formation from E11 AGM cells. (Cii) Bar graph showing the total number of colonies obtained from freshly isolated AGMs or from AGM cells after culture with or without Igf2 (n = 3). In the control cultures an equal volume of diluent was added. (Ciii) Bar graph showing the percentage of colony type obtained in each condition. Error bars indicate SD.