To test whether RBP4 regulates viral infection by additional cellular processes, we expanded our analysis to two genetically unrelated respiratory viruses with distinct entry requirements: Sendai virus (SeV), which strictly requires α-2,3-linked sialic acids [26], and vesicular stomatitis virus (VSV), which binds non-sialic acid receptors [27]. The gene discussed is RBP4; the disease is viral infectious disease.