Second, while we could detect direct binding of mAb RB6-8C5 to virus-specific CD8+ T cells, a direct effect on CD8+ T cells is unlikely to account for our results because (i) CD8+ T cell numbers in the airways were particularly low up to day 5 post-infection, (ii) depletion of CD8+ T cells with anti-CD8 mAb YTS169.4 had no effect on viral titres up to and including day 5 post-infection. Here, CD8A is linked to infection.