Over the last 20 years, modified adenoviruses have been extensively studied as a vehicle for gene delivery to the liver, because of their high transfection efficiency and their natural tropism for hepatocytes [159, 160] . Moreover, the development of the third generation of adenoviral vectors that lack all viral coding sequences (e.g., helper-dependent adenoviral vectors), resulted in their increased capacity and minimized immunogenicity of the vector allowing longterm transgene expression [161] . High cloning capacity of those vectors enables usage of inducible or tissue-specific promoters and coexpression of multiple therapeutic or immunomodulatory genes [162] .