Induction of phosphorylated STAT1 by IFNα2a is not related to IFNα/βR expression in monocytes. Univariate linear regression analysis was used to assess the relationship between IFNα/βR expression and capacity to induce STAT1 phosphorylation. Significant correlation was not observed between induction of phosphorylated STAT1 and expression of IFNα/βR for uninfected persons (r = −0.318, P = .443; A) or HIV-1–infected persons (r = 0.330, P = .249; B).