Development of anti-HER2 conjugated ICG-loaded polymeric nanoparticles for targeted optical imaging of ovarian cancer

Abstract

Targeted delivery of therapeutic and imaging agents using surface modified nanovectors has been explored immensely in recent years. The growing demand for site-specific and efficient delivery of nanovectors entails stable surface conjugation of targeting moieties. We have developed a polymeric nanocapsule doped with Indocyanine green (ICG) with potential for targeted and deep tissue optical imaging and phototherapy. Our ICG-loaded nanocapsules (ICG-NCs) have potential for covalent coupling of various targeting moieties and materials due to presence of amine groups on the surface. Here, we covalently bioconjugate polyethylene glycol(PEG)-coated ICG-NCs with monoclonal antibody against HER2 through reductive amination-mediated procedures. The irreversible and stable bonds are formed between anti-EGFR and aldehyde termini of PEG chains on the surface of ICG-NCs. We confirm the uptake of conjugated ICG-NCs by ovarian cancer cells over-expressing HER2 using fluorescent confocal microscopy. The proposed process for covalent attachment of anti-HER2 to PEGylated ICG-NCs can be used as a methodology for bioconjugation of various antibodies to such nano-constrcuts, and provides the capability to use these optically active nano-probes for targeted optical imaging of ovarian and other cancer types.

Effects of nanoencapsulation and PEGylation on biodistribution of indocyanine green in healthy mice: quantitative fluorescence imaging and analysis of organs

“…9 We have also reported the targeted fluorescent imaging of ovarian cancer cells using anti-human EGFR 2 functionalized ICG-NCs. 58 ICG-NCs can potentially be used as a phototherapeutic agent by generating heat in response to laser irradiation. In a previous study, 59 our group investigated the heat-generating capability of ICG-NCs in response to 808 nm laser irradiation and demonstrated the ability of ICG-NC suspensions to produce temperature rises to ≈80°C.…”

ICG-loaded polymeric nanocapsules functionalized with anti-HER2 for targeted fluorescence imaging and photodestruction of ovarian cancer cells

“…13 The optical characterization of ICG-NCs demonstrated that anti-HER2 functionalization did not compromise near infrared absorption and fluorescence emission of ICG-NCs. 13 …”

“…We have previously reported the synthesis of ICG-NCs and conjugation of anti-HER2 monoclonal antibody to the surface of ICG-NCs using PEG as linker. 11,13 Briefly, we coat the surface of ICG-NCs with single and double aldehyde terminated PEG, right before conjugation of antibody. The PEG coating reduces non-specific protein adsorption to the surface of ICG-NCs and besides the double aldehyde terminated PEG chains are used as linker to covalently conjugate anti-HER2 to ICG-NCs.…”

“…[6][7][8][9][10][11][12] These theranostic agents, indocyanine green-doped nanocapsules (ICG-NCs), can be functionalized with monoclonal anti-epidermal growth factor receptor2 (HER2) for targeted imaging and phototherapy of ovarian cancer cells. 13 Previously, we have shown in-vitro targeted imaging of ovarian cancer cells using anti-HER2 functionalized ICG-NCs. In that study, we optically imaged SKOV3 cell line, with high levels of HER2 expression, using anti-HER2 functionalized ICG-NCs and confocal fluorescent microscopy.…”

“…Our results demontrated that functionalized ICG-NCs were internalized by SKOV3 cells and were accomulating around nucleus periphery. 13 Here, we investigate in-vitro laser induced phototherapy of ovarian cancer cells using anti-HER2 functionalized ICG-NCs and utilizing near infrared laser irradiation.…”