Visualization of liposomes carrying fibrinogen gamma-chain dodecapeptide accumulated to sites of vascular injury using computed tomography.

UNLABELLED

We have constructed liposomes with hemostatic activity as a platelet substitute using moderately thrombocytopenic rats. The liposomes were conjugated with the dodecapeptide (HHLGGAKQAGDV: H12), which is a fibrinogen gamma-chain C-terminal sequence (gamma 400-411). To visualize liposome accumulation at the site of vascular injury by in vivo computed tomography, a water-soluble contrast dye, N,N'-bis[2-hydroxy-1-(hydroxylmethyl)ethyl]-5-[(2S)-2-hydroxylpropanoylamino]-2,4,6-triiodoisophthalamide (iopamidol), was encapsulated into the H12-conjugated liposomes. We achieved direct visualization of specific accumulation of the H12-(iopamidol)liposomes at the jugular vein injured by ferric chloride and succeeded in semiquantitative analyses of the accumulated amount of H12-liposomes in the injured site. We therefore propose that H12-liposomes that are specifically recruited to, and exert their hemostatic activity at the site of vascular injury, have a significant potential as a carrier and/or as an ideal platelet substitute. Furthermore, the H12-(iopamidol)liposomes would also be clinically useful as diagnostic agents for pathological thrombus detection and as contrast dyes for hepatosplenography.

FROM THE CLINICAL EDITOR

The authors have constructed liposomes with hemostatic activity as a platelet substitute using moderately thrombocytopenic rats. They propose that H12-liposomes that are specifically recruited to, and exert their hemostatic activity at the site of vascular injury, have a significant potential as a carrier and/or as an ideal platelet substitute. Furthermore, the H12-(iopamidol) liposomes would also be clinically useful as diagnostic agents for thrombus detection and as contrast dyes for hepatosplenography.