The fact that IL-7 plasma levels did not reach normal levels when HCV became undetectable may suggest that, after the initial decline that follows the drop in viremia, IL-7 plasma levels were regulated, as in HIV-infected patients [33] and in IFNα-treated SIV-infected rhesus macaques [30], as a consequence of lymphocytopenia through either reduced consumption or increased production in lymphoid organs [49]. This evidence concerns the gene IL7 and lymphopenia.