Page 35 - TPIS2022

Lecture title:

Recent progress and evaluation of immune checkpoints in living subjects
for diagnosis and therapy

ABSTRACT:

Cancer cells are activating various immune checkpoint pathways to evade from immune
functions. For example, programmed cell death protein 1 (PD-1) and its ligand 1 (PD-L1)
cytotoxic T lymphocyte antigen-4 (CTLA-4) and CD28 are well known immune check points
(ICs). Recently, several monoclonal antibodies and its fragments are developed to inhibit ICs

in vivo. US FDA already approved several such IC inhibitors (ICI) as cancer therapeutics
and this approach is gaining a lot of momentum. Among the ICIs, blocking of PD-1/PD-L1
or CTLA-4/CD28 or T cell immunoreceptor with Ig (ITIM) and immunoreceptor
tyrosine-based inhibition motif (TIGIT) domains ligands CD155/PVR and CD112/nectin-2
were shown promising therapeutic results. However, there is a need to evaluate these ICs
expressions in various disease conditions in a living subject. Molecular imaging technology
(MIT) provides an attractive noninvasive approach. Immuno positron emission tomography
(immunoPET), and immune targeted microbubbles (ITMB) are few examples of MIT. These
tools can be employed in clinical for diagnosis, staging and monitoring of the cancers and

other diseases. The recent surging activities of antibody development have further increased
the use of ICs imaging. The clinical studies reports have shown that patients with various
malignancies benefit substantially from these ICIs treatments. Overall, MIT potential has
been increasing for clinical translation of human diseases management, and thus in future
it is possible that immune based imaging approaches can be used in routine clinical practice
as like FDG-PET. Diagnostic imaging strategies are expanding significantly and growing fast
within this past decade.

5 International TPCF Preclinical Imaging Symposium (2022) 35
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