Strategies in In Vivo Molecular Imaging
9
Citation
89
Reference
10
Related Paper
Citation Trend
Abstract:
After completing this article, readers should be able to:
1. Describe the emerging field of in vivo molecular imaging.
2. List the various imaging modalities that have been used to detect molecules and track cells in vivo and discuss the basic molecular strategies and principles.
3. Describe several of the selective events, such as binding, enzymatic activation, or molecular switches, that make in vivo imaging of cells and molecules possible.
4. Delineate the strengths and weakness of current imaging strategies.
5. List combined imaging modalities and their use in molecular imaging.
Following cells and molecules in vivo has been a fundamental difficulty in biomedical research. The technologies in the field of in vivo molecular imaging are aimed at obtaining spatiotemporal information about in vivo processes as they occur; that is, monitoring cellular and molecular changes in response to a variety of stimuli in intact animals and eventually in humans. Understanding basic biologic and biochemical mechanisms is required to develop the tools that will enable access to this information.
Traditional imaging modalities largely depend on physical parameters, such as absorption in ultrasonography, x-ray attenuation, or optical scattering, which reveal primarily structural information. For molecular imaging, unique signatures are generated using molecular biology methods that distinctly label host cells, microbial pathogens, tumor cells, or transplanted tissues. These can be detected in vivo by conventional and novel imaging modalities and can be used to examine molecular mechanisms of pathogenesis, facilitate earlier disease detection, and permit evaluation of therapeutic outcomes. The molecular targets for imaging may include DNA, RNA, protein, or protein function. Imaging of inherent levels of DNA, RNA, and protein is difficult, but protein function can be exploited readily for imaging and can be used in reporter gene approaches to create surrogate markers for processes such as messenger RNA (mRNA) and protein synthesis.1,2, …Keywords:
Molecular Imaging
Modalities
Molecular probe
In vivo molecular optical imaging has significant potential to delineate and measure, at the macroscopic level, in vivo biological processes that are occurring at the cellular and molecular level. Optical imaging has already been developed for in vitro and ex vivo applications in molecular and cellular biology (e.g. fluorescence confocal microscopy), but is still at an early stage of development as a whole-animal in vivo imaging technique. Both sensitivity and spatial resolution remain incompletely defined. Rapid advances in hardware technology and highly innovative reporter probes and dyes will be expected to deliver significant insight into perturbations of molecular pathways that occur in disease, ultimately with the potential of translating into future molecular imaging techniques for patients with arthritis. This review will focus on currently available technologies for live in vivo animal optical imaging, including fluorescence reflectance imaging, potential novel tomographic techniques, bioluminescence reporter technology and potential novel labelling techniques, highlighting in particular the potential application of in vivo fluorescence imaging in arthritis.
Molecular Imaging
Fluorescence-lifetime imaging microscopy
Ex vivo
Bioluminescence imaging
Cite
Citations (35)
This paper provides an overview of the field of molecular imaging by giving representative examples to illustrate the excitement and the dynamic nature of this field. On the first paper on molecular imaging, PET, SPECT, and bioluminescence imaging were focused on. In this issue, approaches that are sometimes called "physiologic imaging" or "functional imaging" are concentrated on. Combining targeted imaging and therapy to pursue a "personalized treatment" paradigm is also discussed. The techniques discussed such as magnetic resonance imaging, biomedical ultrasonics and hyperspectral imaging for in vivo optical diagnostics have much less sensitivity than PET or SPECT but these techniques can provide biologic information in vivo that are critical for both enhancing our knowledge of systems biology and also for clinical management of patients.
Molecular Imaging
Bioluminescence imaging
Functional Imaging
Cite
Citations (6)
In vivo molecular imaging is a powerful tool to analyze the human body. Precision medicine is receiving high attention these days, and molecular imaging plays an important role as companion diagnostics in precision medicine. Nuclear imaging with PET or SPECT and optical imaging technologies are used for in vivo molecular imaging. Nuclear imaging is superior for quantitative imaging, and whole-body analysis is possible even for humans. Optical imaging is superior due to its ease of use, and highly targeted specific imaging is possible with activatable agents. However, with optical imaging using fluorescence, it is difficult to obtain a signal from deep tissue and quantitation is difficult due to the attenuation and scattering of the fluorescent signal. Recently, to overcome these issues, optoacoustic imaging has been used in in vivo imaging. In this article, we review in vivo molecular imaging with nuclear and optical imaging and discuss their utility for precision medicine.
Molecular Imaging
Nuclear medicine imaging
Fluorescence-lifetime imaging microscopy
Nuclear imaging
Imaging science
Molecular probe
Cite
Citations (16)
Optical molecular imaging is a powerful imaging method, which can in vivo monitor physiological and pathobiological processes at the cellular and molecular levels, as opposed to the anatomical level, bridging the gap between imaging and biological processes. Because of its relevance in cardiovascular diseases research, the use of this technology for imaging of cardiovascular diseases advances at a rapid pace in the past decade. This review summarizes the optical molecular imaging methods for imaging the specific targets in cardiovascular diseases, which hold promise for in vivo applications in cardiovascular diseases research. Collectively, in vivo optical molecular imaging may be highly suitable for discriminating targets that play key roles in the occurrence and development of the instable atherosclerosis, thrombogenesis, myocardial infarction, myocardial apoptosis, angiogenesis, as well as in cardiac cell transplantation. Keywords: Bioluminescent imaging, cardiovascular diseases, fluorescence molecular tomography, near-infrared fluorescence imaging, optical imaging.
Molecular Imaging
Bioluminescence imaging
Fluorescence-lifetime imaging microscopy
Cite
Citations (0)
Recent advances in optical molecular imaging technology have led to great improvements in image resolution, and are increasingly being applied to non-invasively delineate in vivo physiological and pathological processes at cellular and molecular levels. It provides the potential for the understanding of integrative biology, earlier detection and characterization of disease and the evaluation of treatment. This paper focuses on the typical in vivo optical molecular imaging modalities as well as their potential clinical applications and future development.
Molecular Imaging
Modalities
Modality (human–computer interaction)
Characterization
Cite
Citations (0)
Molecular imaging is a powerful tool to visualize and characterize biological processes at the cellular and molecular level in vivo . In most molecular imaging approaches, probes are used to bind to disease‐specific biomarkers highlighting disease target sites. In recent years, a new subset of molecular imaging probes, known as bioresponsive molecular probes, has been developed. These probes generally benefit from signal enhancement at the site of interaction with its target. There are mainly two classes of bioresponsive imaging probes. The first class consists of probes that show direct activation of the imaging label (from “off” to “on” state) and have been applied in optical imaging and magnetic resonance imaging (MRI). The other class consists of probes that show specific retention of the imaging label at the site of target interaction and these probes have found application in all different imaging modalities, including photoacoustic imaging and nuclear imaging. In this review, we present a comprehensive overview of bioresponsive imaging probes in order to discuss the various molecular imaging strategies. The focus of the present article is the rationale behind the design of bioresponsive molecular imaging probes and their potential in vivo application for the detection of endogenous molecular targets in pathologies such as cancer and cardiovascular disease. Copyright © 2015 John Wiley & Sons, Ltd.
Molecular Imaging
Molecular probe
Cite
Citations (29)
In vivo molecular imaging is the visualization, characterization, and measurement of biological processes at the molecular and cellular levels in humans and other living systems. Among the methodologies used in in vivo molecular imaging, two methodologies are of great interest from the view of high sensitivity. One is nuclear medical imaging, and distribution and kinetics of a radiolabeled molecular probe are measured using positron emission tomography (PET) and single-photon emission computed tomography (SPECT). The other is optical molecular imaging, and distribution and kinetics of a fluorescent probe are measured using a fluorescent imaging instrument. In this review, the development of imaging probes for these two methodologies is briefly discussed. In nuclear medical molecular imaging, based on structure–activity–biodistribution relationship studies for small molecule and the concept of "functional unit-binding multifunctional molecular probe" containing 3 functional units (target recognition unit, signal-releasing unit, linker unit) for peptides and proteins, we developed radiolabeled probes with high and specific accumulation to the target for neuroreceptors, β-amyloid plaques, and tau aggregates in the brain, tumors, atherosclerotic plaques, pancreatic β-cell, myocardial sympathetic nerves, and so on. We also discuss the progression of molecular imaging toward therapy (radiotheranotics). In in vivo optical molecular imaging, taking into account the characteristics of optical imaging, we designed tumor-specific optical imaging probes with characteristic imaging mechanism, including near-infrared (NIR) fluorescent probes and activatable probes. Furthermore, we developed a photoacoustic imaging probe, which enables highly sensitive and high-resolution imaging in deep tissues.
Molecular Imaging
Molecular probe
Biodistribution
Fluorescence-lifetime imaging microscopy
Cite
Citations (25)
Molecular Imaging
Functional Imaging
Molecular probe
Cite
Citations (52)
Advancements in medical imaging have brought about unprecedented changes in the in vivo assessment of cancer. Positron emission tomography, single photon emission computed tomography, optical imaging, and magnetic resonance imaging are the primary tools being developed for oncologic imaging. These techniques may still be in their infancy, as recently developed chemical molecular probes for each modality have improved in vivo characterization of physiologic and molecular characteristics. Herein, we discuss advances in these imaging techniques, and focus on the major design strategies with which molecular probes are being developed.
Molecular Imaging
Modality (human–computer interaction)
Emission computed tomography
Characterization
Molecular probe
Cite
Citations (69)
In vivo optical molecular imaging involves the use of light emitting tracers combined with sophisticated sensing modalities to perform in vivo imaging of genetic and molecular information. In contrast to the classical diagnostic imaging tools which image the end effects of the diseases, optical molecular imaging could enhance our knowledge of biological phenomena, monitor genetic expression and the alteration of cells, and lead to earlier detection of diseases. With the development of exotic molecular probes with easily detectable bioluminescence and fluorescence labels, optical molecular imaging has emerged as an important new field within biomedical imaging. This paper reviews this state-of-the-art imaging technology and signal processing issues to monitor molecular and cellular events in living organisms.
Molecular Imaging
Molecular probe
Fluorescence-lifetime imaging microscopy
Bioluminescence imaging
Cite
Citations (4)