Figure 3. Coimmunoprecipitation of human C1q and NS1 proteins.

(A) Purified NS1 from the supernatants of DENV-infected BHK cells and purified human C1q protein were immunoprecipitated with anti-NS1 polyclonal antibody, and the eluted fractions 1 and 2 (E1 and E2) were subjected to Western blot analysis. Bands of approximately 30 and 50 kDa corresponding to C1q and NS1, respectively, were observed in the elution fraction of the coimmunoprecipitation. (B) C1q was capable of binding anti-NS1 antibody, although the band intensity in the DENV lane E1 was more than four-fold intense than that in the control lane E1. The IgG₁-coated resin eluted a similar amount of C1q as the control. Error bars indicate the standard deviation from three independent experiments, and the p value denotes significant differences from the control.