Targeting of somatostatin receptors expressed in blood cells using quantum dots coated with vapreotide

Abstract

Cancer may be difficult to target, however, if cancer targeted this provides the chance for a better and more effective treatment. Quantum dots (Qdots) coated vapreotide (VAP) as a somatostatin receptors (SSTRs) agonist can be efficient targeting issue since may reduce side effects and increase drug delivery to the target tissue. This study highlights the active targeting of cancer cells by cells imaging with improving the therapeutic outcomes. VAP was conjugated to Qdots using amine-to-sulfhydryl crosslinker. The synthesized Qdots-VAP was characterized by determination of size, measuring the zeta-potential and UV fluorometer. The cellular uptake was studied using different cell lines. Finally, the Qdots-VAP was injected into a rat model. The results showed a size of 479.8 ± 15 and 604.88 ± 17 nm for unmodified Qdots and Qdots-VAP respectively, while the zeta potential of particles went from negative to positive charge which proved the conjugation of VAP to Qdots. The fluorometer recorded a redshift for Qdots-VAP compared with unmodified Qdots. Moreover, cellular uptake exhibited high specific binding with cells which express SSTRs using confocal microscopy and flow cytometry (17.3 MFU comparing to 3.1 MFU of control, P < 0.001). Finally, an in vivo study showed a strong accumulation of Qdots-VAP in the blood cells (70%). In conclusion, Qdots-VAP can play a crucial role in cancer diagnosis and treatment of blood cells diseases when conjugated with VAP as SSTRs agonist. Keywords: Quantum dots, Vapreotide, Somatostatin, Blood, Receptor, Targeting