In vivo photothermal treatment by the peritumoral injection of macrophages loaded with gold nanoshells

Abstract

Photothermal treatment methods have been widely studied for their target specificity and potential for supplementing the limitations of conventional surgical treatments. In this study, we conducted in vivo photothermal treatments using macrophages containing nanoshells as live vectors. We injected macrophages at the peritumoral sites and observed that they had penetrated into the tumor approximately 48 hours after injection. Afterwards, we irradiated with a near-infrared laser for 2 minutes at 1 W/cm 2 , causing cancer cell death. Our study identified the optimal conditions of the photothermal treatment and confirmed the feasibility of its use in in vivo treatments. de Vries, "MRI of monocyte infiltration in an animal model of neuroinflammation using SPIO-labeled monocytes or free USPIO," J.

Multifunctional Liposomes for Image‐Guided Intratumoral Chemo‐Phototherapy

“…Liposomes act as an extra protection layer to the drug, slowing the drainage of small molecules, which upon 24 h delay prior to laser treatment, can enhance the drug distribution to other tumor sites. Similar behavior has been observed using macrophages as carriers of nanoshells for photothermal therapy . Although all mice tolerated the treatment, toxicity studies were not performed in this preliminary proof of principle work.…”

Macrophage-based cell therapies: The long and winding road

“…The Gendelman group has loaded MΦs with super paramagnetic iron oxide nanoparticles for imaging purposes [104], whereas the Baek and Hirschberg groups have loaded gold nanoshells into MΦs for photothermal therapies [110, 111]. Both of these applications take advantage of the trafficking aspect of MΦs to disease sites, but their effects are triggered by external sources, so they do not have to be released from the MΦ.…”

“…Histological analysis of the tumor for the gold nanoshells post photothermal therapy revealed the vast majority of gold remained immediately adjacent to the injection site as large aggregates, indicating minimal migration of the MΦ away from the injection site into the tumor [110]. Human monocytes loaded with gold nanoshells intravenously injected into nude mice with human MDA-MB-231 BR brain metastases were able to cross the blood brain barrier and co-localized with metastatic sites 24 hours post injection.…”

“…For example, luciferase or fluorescent protein activity is rapidly lost when not within a cell, so detection of these proteins can be used as a method to determine the viability of transplanted cells [135–137]. Due to the lack of PK/BD data on systems where signal is coupled directly to cell viability, the efficiency (percentage of administered cells that lodge in the target site and their survival time) and extent of engraftment has not been determined [78, 79, 81, 99, 100, 103, 104, 106, 110, 116, 120]. …”

Cell Mediated Photothermal Therapy of Brain Tumors

“…As was observed in in vitro experiments, high energy levels (0.6 kJ) were required to achieve inhibition of tumor development. In related experiments, Yang et al (2015) injected Ma into peri-tumoral sites in experimental squamous cell tumors in mice. Penetration of the Ma throughout the tumor was observed approximately 48 h after injection.…”