Fig. 1.

17β-estradiol (E₂) inhibits infectious virus production in human nasal epithelial cell (hNEC) from female, but not male, donors. hNEC cultures from female (A) or male (B) donors were pretreated with E₂ (0.1, 1, and 10 nM) or vehicle for 24 h in the basolateral media and then infected with influenza A virus [IAV; multiplicity of infection (MOI) = 0.1 50% tissue culture infectious dose (TCID₅₀)/cell] via the apical membrane. Supernatants were collected every 24 h postinfection (hpi) and virus titers were analyzed by TCID₅₀ assay. The limit of detection is indicated by a dotted line. The data represent means ± SE. *P < 0.05, E₂-treated cultures were significantly different from sex-matched vehicle controls based on a multivariate analysis of variance (MANOVA) followed by planned comparisons, with n = 15 hNEC wells per treatment group.