Antibody - Conjugated Superparamagnetic Iron Oxide Nanoparticles for Active Targeting of Adenosine Receptors

Superparamagnetic iron oxide nanoparticles (SPIO) are regarded as advanced tools in biomedical science in disease diagnostics and therapies. We report the synthesis of antibody-conjugated nanoparticles (Ab-SPIO) that combine MRI behavior of nanoparticles with the selective and specific targeting of cellular proteins. Our novel Ab-SPIO will serve as a MRI biomarker for preventive PAH diseases. It is known that adenosine 1-type receptors (A1R) are involved in several cardiovascular diseases and offer promising therapeutic potential. In our study, we developed new A1R antibodies (Ab) conjugated SPIO nanocarriers as a specific Ab-MRI contrast agent. Spherical magnetite nanoparticles with a hydrodynamic diameter of 145 nm and particle size distribution of 15 - 60 nm were obtained. Surface of SPIO nanoparticles was stabilized by biocompatible polymer carboxymethyl cellulose (CMC) and precisely characterized in stability by measuring of zeta potential (- 43 mV). Strong magnetic response with a saturation magnetization of 75 Am2/kg confirmed appropriate magnetic behavior for MRI application. Oriented immobilization of antibody (Adenosine A1-R Antibody (H-40)) on free carboxyl groups of CMC provides active targeting of adenosine receptors. We conducted microscopic evaluation of the Ab-SPIO probe in VVEC cells, localization (plasma membrane vs. intracellular), and we determined the effects of hypoxia on A1R expression, compared A1R expression in VVEC-Hyp vs. VVEC-Co, and determined the effects of acute hypoxia on A1R expression in VVEC-Hyp vs. VVEC-Co. The experiments are proposed for MRI imaging of VV in control and hypoxic animals. Functionalized A1R-Ab-SPIO complexes will be utilized as a specific MRI biomarker in early disease diagnostics.