Next Generation Imaging Techniques to Define Immune Topographies in Solid Tumors

Abstract

In recent years, cancer immunotherapy experienced remarkable developments and it is nowadays considered a promising therapeutic frontier against many types of cancer, especially hematological malignancies. However, in most types of solid tumors, immunotherapy efficacy is modest, partly because of the limited accessibility of lymphocytes to the tumor core. This immune exclusion is mediated by a variety of physical, functional and dynamic barriers, which play a role in shaping the immune infiltrate in the tumor microenvironment. At present there is no unified and integrated understanding about the role played by different postulated models of immune exclusion in human solid tumors. Systematically mapping immune landscapes or “topographies” in cancers of different histology is of pivotal importance to characterize spatial and temporal distribution of lymphocytes in the tumor microenvironment, providing insights into mechanisms of immune exclusion. Spatially mapping immune cells also provides quantitative information, which could be informative in clinical settings, for example for the discovery of new biomarkers that could guide the design of patient-specific immunotherapies. In this review, we aim to summarize current standard and next generation approaches to define Cancer Immune Topographies based on published studies and propose future perspectives.

Histopathological Features of Parathyroid Adenoma and 18F-Choline Uptake in PET/MR of Primary Hyperparathyroidism

“…There are several limitations of our study. Autoradiography (ARG) is the criterion standard used for the detection of tracertissue interactions on histological samples 38,39 ; however, ARG was not performed in our study. Nevertheless, ARG of (avital) fresh frozen tissue is only able to visualize binding interactions, and cannot show functional uptake.…”

Cancer immune exclusion: breaking the barricade for a successful immunotherapy

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Non-invasive cell-tracking methods for adoptive T cell therapies

“…31 In addition, cell tracking could be used to detect the occurrence of host immune responses against the graft, which will lead to a loss of signal, or to detect off-tumor responses at an early stage, thus reducing the severity of ACTrelated adverse effects. 22,[32][33][34][35] This review focuses mainly on clinically applica-155 ble imaging modalities for T cell tracking in ACT. The in vivo tracking of ACTs can be performed through either 160 direct or indirect cell labeling.…”