Imprime interacts with endogenous IgG and IgM ABA in human serum.

<p>(A) The surface IgG and IgM ABA on vehicle- or Imprime-treated neutrophils and monocytes were detected by flow cytometry using rabbit anti-human IgG- and IgM-specific Abs, respectively, after Imprime was incubated with WB at 37°C for 30 mins. The MFI and percentage of IgG- or IgM-positive cells are indicated on the contour plots. Data shown are representative of 3 independent experiments. (B) The ability of an Imprime-conjugated bead column to selectively bind and retain IgG (filled bar) and IgM (empty bar) ABA from human serum is shown. The percentage of ABA in the flow-through (FT) and the eluate was measured based on the serum ABA concentration pre-loaded on the column. The ABA eluted off the Imprime-conjugated bead column along with purified IgG and IgM controls were resolved by SDS-PAGE under reducing conditions. Protein bands corresponding to the heavy and light chain of IgG and IgM were observed by Coomassie staining (left panel), or detected by immunoblotting with an anti-IgG Ab (middle panel) or anti-IgM heavy chain Ab (right panel).