MKI67 and viral encephalitis: As shown by immunohistochemical analyses, ganciclovir did not reduce numbers of proliferating microglia (Iba1+/Ki67+) and total numbers of microglia (Iba1+) neither during TMEV (Fig. 1E,F), nor during cuprizone induced demyelination and the subsequent remyelination (Fig. 2B,C), nor during VSV induced encephalitis (Fig. 3B,C).