E-Selectin-Binding Peptide-Modified Bovine Serum Albumin Nanoparticles for the Treatment of Acute Lung Injury

Currently, there is no specific treatment for acute lung injury (ALI). E-selectin-binding peptide (Esbp), a high-affinity peptide that delivers drugs targeting inflammatory vascular endothelial cells, can bind to E-selectin and act as a targeting ligand for selective drug delivery. In this study, we coupled the thiol groups of Esbp to the amino groups on the surface of bovine serum albumin (BSA) using succinimidyl iodoacetic acid to make Esbp-modified BSA nanoparticles (BSANPs) at the average ratio of 19.3 mu g Esbp to 1mg BSA. The Esbp-modified BSANPs were spherical in shape and had a particle size of 266.7 +/- 2.7nm, polydispersity index of 0.165 +/- 0.02, zeta potential of -33.64 +/- 1.23mV, encapsulation efficiency of 84.3 +/- 2.3%, and drug loading of 6.7 +/- 0.32%. The cumulative release rate of dexamethasone-loaded Esbp-modified BSANPs was 51.2% within 12h, significantly lower than that of 88.2% of free drugs. Moreover, Esbp-modified BSANPs could be uptaken in vitro by activated human umbilical vein endothelial cells and in vivo by the lungs of the established ALI mouse model. These results indicated that our Esbp-modified BSANPs delivery system has characteristics of good targeting ability and biocompatibility and is able to inhibit inflammation. Overall, our Esbp-modified BSANPs delivery system has therapeutic potentials as a new targeting drug system for the treatment of ALI in the future.