Fig. 5

Deposition of mouse common complement components and inhibitors of the complement system on PNPs. The proteins adsorbed on PNPs were analyzed by LC-MS/MS (data presented as abundance values, arbitrary values generated by mass spec peak integration, n = 4) and Western blot (WB) analyses. LC-MS/MS data are shown as boxplot with median value. The deposition of common complement proteins (e.g., C3, C5, C6, C7, C8, C9) was quantified by LC-MS/MS analyses (A). To better evaluate complement activation, C3 fragmentation was studied by WB (B, C3α’: 63 kDa; C3α’2: 40 kDa). WB was also used to highlight the deposition of C9 (C, attended band at ~ 75 kDa), a terminal component of the complement activation. Complement inhibitors (D) were quantified by LC-MS/MS analysis. uPNPs: untargeted nanoparticles; tPNPs: targeted nanoparticles; MS: mouse serum; C1 inh: C1 inhibitor; C4BP: C4 binding proteins; empty: empty well