Magnetic Resonance Imaging of Tumor-Infiltrating Lymphocytes by Anti-Cd3-Conjugated Iron Oxide Nanoparticles Publisher Pubmed



Pournoori N^{1, 2} ; Oghabian MA^{1, 2} ; Irajirad R³ ; Muhammadnejad S^{4, 5} ; Delavari H H⁶
Source: ChemMedChem Published:2022

Abstract

Immune checkpoint blockade, considered a revolutionary approach in cancer treatment, is only effective in patients with high tumor-infiltrating lymphocytes (TILs). This work aimed to investigate the feasibility of targeted contrast agent (CA) based on dextran-coated superparamagnetic iron oxide nanoparticles (SPIONs-DEX) for TILs detection by magnetic resonance imaging (MRI) studies. To do so, we synthesized an MRI CA by conjugating SPIONs-DEX to an anti-CD3 monoclonal antibody via cyanogen bromide as a cross-linker. In vitro assessments demonstrated the higher labeling efficiency of the developed CA to CD3+ lymphocytes compared to SPIONs-DEX. In vivo MRI of a xenograft model of CD3+ lymphocytes revealed the significant signal loss after the intravenous injection of the bioconjugate by ∼34 % and 21 % in T2*-weighted and T2-weighted images, respectively. The histopathological evaluation of xenograft tumors confirmed the labeling of lymphocytes by the targeted CA. This approach could open up a new horizon in the non-invasive assessment of TILs to identify patients eligible for immunotherapy. © 2022 Wiley-VCH GmbH.