Fig. 7. Ferritin protein levels were estimated in bcl-x L–overexpressing, bcl-2 –overexpressing, β-galactosidase–expressing, and mock-infected controls by immunoblotting. Quantitation by scanning densitometry and averaging of three experiments is shown ( A and B ). * P < 0.05 compared to control or β-galactosidase. The two immunopositive bands of ferritin, the heavy (H) subunit (approximately 22 kDa) and the light (L) subunit (approximately 19kDa) are indicated by arrows in an individual western blot ( C ). Thirty micrograms total protein was loaded per condition. The immunopositive bands for ferritin were greater in bcl-x Land bcl-2 overexpressing cultures than in controls. The ferritin L-subunit band was barely detected in controls.