RGDfK-functionalized gold nanorods bind only to activated platelets.

Area of Science:

• Biomaterials Science
• Nanotechnology
• Oncology

Background:

• Integrin-targeting peptide RGDfK-labeled gold nanorods (GNR) are investigated for targeted hyperthermia in solid tumors.
• Overexpressed integrin αvβ3 on tumor vasculature presents a target, but RGD peptide promiscuity raises concerns about off-target binding, particularly to platelets via αIIbβ3.

Purpose of the Study:

• To evaluate the interaction of RGDfK-labeled GNR with platelets.
• To determine if these GNR alter platelet function, potentially impacting bleeding or thrombosis risks.

Main Methods:

• Assessed GNR interaction with resting and activated platelets in platelet-rich plasma (PRP).
• Measured platelet activation markers and platelet aggregation in whole blood and PRP with RGDfK-GNR.
• Investigated GNR effects on platelet function post-activation.

Main Results:

• RGDfK-GNR showed minimal binding to resting platelets but actively bound to activated platelets.
• RGDfK-GNR did not induce platelet activation or significantly affect platelet aggregation in PRP or whole blood.
• No significant impact on platelet function was observed with RGDfK-GNR alone.

Conclusions:

• RGDfK-labeled GNR exhibit limited direct impact on platelet function in plasma.
• Potential for nonspecific binding in vascular beds with activated platelets (spleen, liver) warrants further investigation for toxicity risks.