Surface biotinylation of cytotoxic T lymphocytes for in vivo tracking of tumor immunotherapy in murine models

Abstract

Currently, there is no stable and flexible method to label and track cytotoxic T-lymphocytes (CTLs) in vivo in CTL immunotherapy. We aimed to evaluate whether the sulfo-hydroxysuccinimide (NHS)-biotin-streptavidin (SA) platform could chemically modify the cell surface of CTLs for in vivo tracking. CD8+ T lymphocytes were labeled with sulfo-NHS-biotin under different conditions and then incubated with SA-Alexa647. Labeling efficiency was proportional to sulfo-NHS-biotin concentration. CD8+ T lymphocytes could be labeled with higher efficiency with sulfo-NHS-biotin in DPBS than in RPMI (P<0.05). Incubation temperature was not a key factor. CTLs maintained sufficient labeling for at least 72 hours (P<0.05), without altering cell viability. After co-culturing labeled CTLs with mouse glioma stem cells (GSCs) engineered to present biotin on their surface, targeting CTLs could specifically target biotin-presenting GSCs and inhibited cell proliferation (P<0.01) and tumor spheres formation. In a biotin-presenting GSC brain tumor model, targeting CTLs could be detected in biotin-presenting gliomas in mouse brains but not in the non-tumor-bearing contralateral hemispheres (P<0.05). In vivo fluorescent molecular tomography (FMT) imaging in a subcutaneous U87 mouse model confirmed that targeting CTLs homed in on the biotin-presenting U87 tumors but not the control U87 tumors. PET imaging with 89Zr-deferoximne-biotin and SA showed a rapid clearance of the PET signal over 24 hrs in the control tumor, while only minimally decreased in the targeted tumor. Thus, sulfo-NHS-biotin-SA labeling is an efficient method to noninvasively track the migration of adoptive transferred CTLs and does not alter CTL viability or interfere with CTL-mediated cytotoxic activity.

In Vivo PET Imaging of the Activated Immune Environment in a Small Animal Model of Inflammatory Arthritis

“…Imaging targets have included PD-1/PD-L1, translocator protein, CD8 + T cells, T cell receptor (TCR)-transgenic T cells, and others. 27 - 33 A minority of these approaches has been translated into humans. 34 …”

In Vivo MR Imaging of Glioma Recruitment of Adoptive T‐Cells Labeled with NaGdF4‐TAT Nanoprobes

“…As described by Dodd et al, the first 72 h of the immune response would be extremely informative. [3a,5] Thus, in our study, the time points of 12, 24, 48, and 72 h postinjection of labeled T‐cells were chosen for T 1 ‐weighted MRI. As illustrated in Figure a, localized hyperintensity (indicated by red arrowheads), resulting from infiltration of NaGdF 4 ‐TAT labeled T‐cells, could be effectively detected in the orthotopic glioma region 24, 48, and 72 h postinjection.…”

“…Molecular imaging is the preferred approach for tracking immune cells in vivo, using magnetic resonance imaging (MRI), optical imaging[3a,8] or positron emission tomography . Owing to its advantages of safety, high resolution, and direct applicability for cell tracking in clinical studies, MRI is widely used to image immune cell delivery for the visualization of cell homing and engraftment,[7b] cell physiology, and gene expression.…”

“…Tumor‐specific T‐cell‐based adoptive cellular immunotherapy, one novel therapeutic modality that can specifically target the glioma‐associated surface antigen, has emerged to be a potentially highly valuable treatment option in recent years. [1b,3] However, the process to gain regulatory approval from bench to bedside has languished mostly due to the poor understanding of biological behaviors and functionality of the adoptively transferred T‐cells in vivo. [3b,4] Longitudinal noninvasive tracking and quantitative analysis of cytotoxic T‐cells, particularly in the first 72 h of the immune response,[3a,5] can informatively track the migration pathways, characterize biodistribution, and objectively evaluate the effectiveness against gliomas.…”

“…[1b,3] However, the process to gain regulatory approval from bench to bedside has languished mostly due to the poor understanding of biological behaviors and functionality of the adoptively transferred T‐cells in vivo. [3b,4] Longitudinal noninvasive tracking and quantitative analysis of cytotoxic T‐cells, particularly in the first 72 h of the immune response,[3a,5] can informatively track the migration pathways, characterize biodistribution, and objectively evaluate the effectiveness against gliomas. Such technology could lay the foundation for safe and efficient immunotherapies using adoptively transferred T‐cells.…”