Pathogen-mimicking MnO nanoparticles for selective activation of the TLR9 pathway and imaging of cancer cells

Here, design of the first pathogen-mimicking metal oxide nanoparticles with the ability to enter cancer cells and to selectively target and activate the TLRf pathway, and with optical and MR imaging capabilities, is reported. The immobilization of ssDNA (CpG ODN 2006) on MnO nanoparticles is performed via the phosphoramidite route using a muitifunlnal poivme. The multifunctional polymer used for the nanoparticle surface modification not only affords a protective organic biocompatible shell but also provides an efficient and convenient means for loading imunostimulatory oligonucleotides. Since fluorescent molecules are amenable to photodetection, a chromophore (Rhodamine) is introduced into the polymer chain to trace the nanoparticles in Caki-1 (human kidney cancer) cells. The ssDNA coupled nanoparticles are used to target Toll-like receptors 9(TLR9) receptors inside the cells and to activate the classical TLR cascade. The presence of TLR9 is demonstrated independently in the Caki-1 cell line by western blottingand immunostaining techniques. The magnetic properties of the MnO core make fiinctionalized MnO nanoparticles potential diagnostic agents for magnetic resonance imaging (MRI) Leb, enabling multimodal detection by a combination of MR and optical imaging methods. The trimodal nanoparticles alow the imaging of cellular trafficking by different means and simultaneously are an effective drug carrier system.