Furthermore, by including a condition in which hSP-D was administered instead of iSP-D, it was demonstrated that hSP-D could not prevent infection-induced weight loss while only a small reduction in lung virus titers was observed, consistent with previous observations in vitro that showed resistance of A/California/E9/09 (H1N1) for neutralization by hSP-D. This evidence concerns the gene HSP90B2P and infection.