Effect of regulated Epo gene therapy on the spleen and liver in Epo-TAg^h mice.

(A-D) TER-119 staining to reveal cells of the erythropoietic lineage in the spleen. TER-119 recognizes a molecule associated with cell-surface glycophorin A. Therefore, erythroid cells were identified by membrane-associated staining. (A) Healthy spleen. (B) Epo-TAg^h spleen. (C) Healthy spleen treated with AAV-HREEpo. (D) Epo-TAg^h spleen treated with AAV-HREEpo. Treatment of the Epo-TAg^h mice with AAV-HREEpo stimulates erythropoiesis in the spleen. Compare level of TER-119 staining in panels B and D. (E-H) Perl Prussian blue staining to reveal nonheme iron in (E) healthy liver, (F) Epo-TAg^h liver, (G) healthy liver treated with AAV-HREEpo, and (H) Epo-TAg^hliver treated with AAV-HREEpo. Treatment of the Epo-TAg^hmice with AAV-HREEpo causes a reduction in the hepatic iron loading. Compare Perl staining in panels F and H. Original magnification, × 200.