Western blot analysis under reducing conditions (10% SDS) of plasma membrane fractions prepared from cell surface biotinylated THP-1 cells and human monocytes.

(A) S100A9 in the biotinylated plasma membrane fraction of THP-1 cells: non-biotinylated membrane fraction (lane a) and biotinylated cell surface fraction (lane b). (B) S100A8 expression in biotinylated THP-1 cells (same sample fractions as in (A). (C) Expression of S100A9 (left) and S100A8 (right) in the non-biotinylated membrane fraction (lane a) and biotinylated cell surface fraction (lane b) of human monocytes. Antibodies used were; α-S100A9 (NOVUS clone 1C10) and α-S100A8 (BMA; T1030; clone 8-5C2). 4 ng recombinant hS100A9 (rA9) was loaded.