Fluorescence Imaging Platform Research Articles

Bilayer MOF nanomachine for precision breast cancer cell fluorescent imaging and therapy.

Abilayer MOF reporter (ZIF-67@FAM-mRNA@ZIF-8) was synthesized, and the ZIF-67 was used as a carrier and fluorescent quencher to connect the FAM reporter through electrostatic adsorption and coordination effect. The ZIF-8 covering the outer layer can improve the stability of the probe and cell permeability, which helps the FAM reporter effectively release. After entering the cancer cells, the acidic environment in the cells induced the decomposition of ZIF-8. The excess ATP in the tumor cells competitively binds ZIF-67, causing the FAM reporter to shed and restore fluorescence. The shed FAM reporter was specifically bound to the overexpressed miRNA-21 in breast cancer cells to achieve fluorescence imaging and therapy of breast cancer. The results of specific imaging and apoptosis experiments of breast cancer cells indicate that bilayer MOF nanomachine provides an effective nanotherapy platform for accurate fluorescence imaging.

Singlet oxygen production of Zn-Ag-In-S quantum dots for photodynamic treatment of cancer cells and bacteria.

Zn-Ag-In-S (ZAIS) quantum dots (QDs) were synthesized with various Ag-to-In ratios and used as novel photosensitizers for photodynamic therapy (PDT) on cancer cell inhibition and bacterial sterilization, and their structural, optical, and photodynamic properties were investigated. The alloyed QDs displayed a photoluminescence quantum yield of 72% with a long fluorescence lifetime of 5.3μs when the Ag-to-In ratio was 1:3, suggesting a good opportunity as a dual functional platform for fluorescence imaging and PDT. The ZAIS QDs were then coated with amphiphilic brush copolymer poly(maleic anhydride-alt-1-octadecene) (PMAO) before application. The 1O2 quantum yield of the ZAIS/PMAO was measured to be 8%, which was higher than previously reported CdSe QDs and comparable to some organic photosensitizers. Moreover, the ZAIS QDs showed excellent stability in aqueous and biological media, unlike organic photosensitizers that tend to degrade over time. The in vitro PDT against human melanoma cell line (A2058) and Staphylococcus aureus shows about 30% inhibition rate upon 20min light irradiation. Cell staining images clearly demonstrated that co-treatment with ZAIS QDs and light irradiation effectively killed A2058 cells, demonstrating the potential of ZAIS QDs as novel and versatile photosensitizers for PDT in cancer and bacterial treatment, and provides useful information for future designing of QD-based photosensitizers.

Multi-scale tissue fluorescence mapping with fiber optic ultraviolet excitation and generative modeling

Cellular imaging of thick samples requires physical sectioning or laser scanning microscopy, which can be restrictive, involved, and generally incompatible with high-throughput requirements. We developed fiber optic microscopy with ultraviolet (UV) surface excitation (FUSE), a portable and quantitative fluorescence imaging platform for thick tissue that enabled quick sub-cellular imaging without thin sections. We substantially advanced prior UV excitation approaches with illumination engineering and computational methods. Optical fibers delivered <300nm light with directional control, enabling unprecedented 50× widefield imaging on thick tissue with sub-nuclear clarity, and 3D topography of surface microstructure. Probabilistic modeling of high-magnification images using our normalizing flow architecture FUSE-Flow (made freely available as open-source software) enhanced low-magnification imaging with measurable localized uncertainty via variational inference. Comprehensive validation comprised multi-scale fluorescence histology compared with standard H&E histology, and quantitative analyses of senescence, antibiotic toxicity, and nuclear DNA content in tissue models via efficient sampling of thick slices from entire murine organs up to 0.4×8×12mm and 1.3 million cells per surface. This technology addresses long-standing laboratory gaps in high-throughput studies for rapid cellular insights.

New Near-Infrared Fluorescence Imaging Platform with Large Stokes Shift for Carboxylesterase 2 Detection in Thyroid Cancer and Inflammatory Diseases Diagnosis.

Development of new near-infrared fluorophores is one of the eternal themes in the field of biosensing and biological imaging. In this work, we constructed a novel fluorophore platform MOR by replacing methylindole of hemicyanine fluorophore (CyR) with benzoxazole to acquire better fluorescence characteristics. Based on the platform, a near infrared (NIR) fluorescent probe MOR-CES2 was synthesized for the specific "off-on" response to carboxylesterase 2 (CES2). The probe exhibited excellent properties including near-infrared emission (735 nm), large Stokes shift (105 nm), high sensitivity (LOD, 0.3 ng/mL), and rapid response (15 min). The successful application of MOR-CES2 in biological imaging of CES2 in mice with thyroid cancer and inflammatory bowel disease demonstrated that the probe could identify cancer cells and tissues and sensitively respond to inflammation. The results proved the potency of MOR-CES2 as an efficient imaging tool to assist in the surgical resection of CES2-related tumors.

In situ single-cell therapeutic response imaging facilitated by the TRIPODD fluorescence imaging platform.

Purpose: Small molecule drugs such as tyrosine kinase inhibitors (TKIs) targeting tumoral molecular dependencies have become standard of care for numerous cancer types. Notably, epidermal growth factor receptor (EGFR) TKIs (e.g., erlotinib, afatinib, osimertinib) are the current first-line treatment for non-small cell lung cancer (NSCLC) due to their improved therapeutic outcomes for EGFR mutated and overexpressing disease over traditional platinum-based chemotherapy. However, many NSCLC tumors develop resistance to EGFR TKI therapy causing disease progression. Currently, the relationship between in situ drug target availability (DTA), local protein expression and therapeutic response cannot be accurately assessed using existing analytical tools despite being crucial to understanding the mechanism of therapeutic efficacy. Procedure: We have previously reported development of our fluorescence imaging platform termed TRIPODD (Therapeutic Response Imaging through Proteomic and Optical Drug Distribution) that is capable of simultaneous quantification of single-cell DTA and protein expression with preserved spatial context within a tumor. TRIPODD combines two complementary fluorescence imaging techniques: intracellular paired agent imaging (iPAI) to measure DTA and cyclic immunofluorescence (cyCIF), which utilizes oligonucleotide conjugated antibodies (Ab-oligos) for spatial proteomic expression profiling on tissue samples. Herein, TRIPODD was modified and optimized to provide a downstream analysis of therapeutic response through single-cell DTA and proteomic response imaging. Results: We successfully performed sequential imaging of iPAI and cyCIF resulting in high dimensional imaging and biomarker assessment to quantify single-cell DTA and local protein expression on erlotinib treated NSCLC models. Pharmacodynamic and pharmacokinetic studies of the erlotinib iPAI probes revealed that administration of 2.5 mg/kg each of the targeted and untargeted probe 4 h prior to tumor collection enabled calculation of DTA values with high Pearson correlation to EGFR, the erlotinib molecular target, expression in the tumors. Analysis of single-cell biomarker expression revealed that a single erlotinib dose was insufficient to enact a measurable decrease in the EGFR signaling cascade protein expression, where only the DTA metric detected the presence of bound erlotinib. Conclusion: We demonstrated the capability of TRIPODD to evaluate therapeutic response imaging to erlotinib treatment as it relates to signaling inhibition, DTA, proliferation, and apoptosis with preserved spatial context.

Smartphone-Based Fluorescent Profiling of Quaternary MicroRNAs in Urine for Rapid Diagnosis of Urological Cancers Using a Multiplexed Isothermal Exponential Amplification Reaction.

Urological cancers such as bladder or prostate cancer represent one of the most malignant tumors that accounts for an extremely high mortality. However, conventionally standard diagnostics for urological cancers are hardly available in low-resource settings. We developed herein a hand-held fluorescent imaging platform by integrating a multiplexed isothermal exponential amplification reaction (EXPAR) with a microgel-enriched methodology for sensitive profiling of quaternary microRNAs (miRNAs) in urine and quick diagnosis of urological cancers at the early stage. The target miRNA mixtures in the urine underwent four parallel EXPARs without cross-reactivity, followed by surface concentration and hybridization by the encoded polyacrylamide microgels. This mix-and-read strategy allowed for one-pot analysis of several key miRNAs simultaneously and provided 5-fold enhancement in fluorescent detection sensitivities compared to the individual EXPAR-based assays. Four urinary miRNAs (let-7a, miRNA-155, -223, and -143) could be quantitatively determined in a wide linear range from 50 fM to 30 nM, with the limits of detection at femtomolar levels. Using a smartphone-based imaging microreader, healthy and cancerous cohorts with prostate, bladder, and renal cell cancers could be discriminated in 30 min with the accuracy >83% using linear discriminant analysis. The developed detection platform has proven to be a portable, noninvasive, and useful complement to the toolbox for miRNA-based liquid biopsies, which holds immense potential and advantage for regular and large-scale applications in early cancer diagnosis.

Dual-Signal Imaging Mode Based on Fluorescence and Electrochemiluminescence for Ultrasensitive Visualization of SARS-CoV-2 Spike Protein.

Accurate and reliable detection of SARS-CoV-2 is critical for the effective prevention and rapid containment of COVID-19. Current approaches suffer from complex procedures or a single signal readout, resulting in an increased risk of false negatives and low sensitivity. Here, we developed a fluorescence (FL) and electrochemiluminescence (ECL) dual-mode imaging platform based on a self-powered DNAzyme walker to achieve accurate surveillance of SARS-CoV-2 spike protein at the single-molecule level. The specific activation of the DNAzyme walker by the target protein provides the power for the system's continuous running, enabling the simultaneous recording of the reduction in fluorescence spots and the appearance of ECL spots generated by the Ru-doped metal-organic framework (MOF) emitter. Therefore, the constructed imaging platform can achieve dual-mode detection of spike protein via reverse dual-signal feedback, which could effectively eliminate false-positive or false-negative signals and improve the detection accuracy and sensitivity with a low detection limit. In particular, the dual-mode accuracy of spike protein diagnosis in samples has been significantly improved compared to single-signal output means. In addition, this dual-mode imaging platform may become a prospective diagnostic device for other infectious viruses.

Dual-Mode Gold Nanocluster-Based Nanoprobe Platform for Two-Photon Fluorescence Imaging and Fluorescence Lifetime Imaging of Intracellular Endogenous miRNA.

Bioimaging is widely used in various fields of modern medicine. Fluorescence imaging has the advantages of high sensitivity, high selectivity, noninvasiveness, in situ imaging, and so on. However, one-photon (OP) fluorescence imaging has problems, such as low tissue penetration depth and low spatiotemporal resolution. These disadvantages can be solved by two-photon (TP) fluorescence imaging. However, TP imaging still uses fluorescence intensity as a signal. The complexity of organisms will inevitably affect the change of fluorescence intensity, cause false-positive signals, and affect the accuracy of the results obtained. Fluorescence lifetime imaging (FLIM) is different from other kinds of fluorescence imaging, which is an intrinsic property of the material and independent of the material concentration and fluorescence intensity. FLIM can effectively avoid the fluctuation of TP imaging based on fluorescence intensity and the interference of autofluorescence. Therefore, based on silica-coated gold nanoclusters (AuNCs@SiO2) combined with nucleic acid probes, the dual-mode nanoprobe platform was constructed for TP and FLIM imaging of intracellular endogenous miRNA-21 for the first time. First, the dual-mode nanoprobe used a dual fluorescence quencher of BHQ2 and graphene oxide (GO), which has a high signal-to-noise ratio and anti-interference. Second, the dual-mode nanoprobe can detect miR-21 with high sensitivity and selectivity in vitro, with a detection limit of 0.91 nM. Finally, the dual-mode nanoprobes performed satisfactory TP fluorescence imaging (330.0 μm penetration depth) and FLIM (τave = 50.0 ns) of endogenous miR-21 in living cells and tissues. The dual-mode platforms have promising applications in miRNA-based early detection and therapy and hold much promise for improving clinical efficacy.

A new multi-parameter imaging platform for in vivo drug efficacy evaluation of ischemic stroke

Ischemic stroke with high incidence and disability rate severely endangers human health. Current clinical treatment strategies are quite limited, new drugs for ischemic stroke are urgently needed. However, most existing methods for the efficacy evaluation of new drugs possess deficiencies of divorcing from the true biological context, single detection indicator and complex operations, leading to evaluation biases and delaying drug development process. In this work, leveraging the advantages of fluorescence imaging with non-invasive, real-time, in-situ, high selectivity and high sensitivity, a new multi-parameter simultaneous fluorescence imaging platform (MPSFL-Platform) based on two fluorescence materials was constructed to evaluate the efficacy of new drug for ischemic stroke. Through simultaneous fluorescence observing three key indicators of ischemic stroke, malondialdehyde (MDA), formaldehyde (FA), and monoamine oxidase A (MAO-A), the efficacy evaluations of three drugs for ischemic stroke were real-time and in-situ performed. Compared with edaravone and butylphthalide, edaravone dexborneol exhibited better therapeutic effect by using MPSFL-Platform. The successful establishment of MPSFL-Platform is serviceable to accelerate the conduction of preclinical trial and the exploration of pathophysiology mechanism for drugs related to ischemic stroke and other brain diseases, which is perspective to promote the efficiency of new drug development.

Rational design of molecular phototheranostic platform for NIR-II fluorescence imaging guided chemodynamic-photothermal combined therapy

The strategy of synergetic chemodynamic treatment (CDT) and photothermal therapy (PTT) to improve the anticancer effect has been a hot spot in the field of biomedicine. Herein, a high-performance near-infrared II (NIR-II) fluorescence imaging-guided molecular phototheranostic platform (IR-FE-Fc@DSPE-S-S-PEG) was designed via a convenient strategy. IR-FE-Fc@DSPE-S-S-PEG can serve as a PTT agent to kill cancer cells under near-infrared laser (808 nm) irradiation and a CDT agent to convert the endogenously less reactive H2O2 into the harmful •OH, simultaneously deplete the glutathione (GSH) to achieve an amplified CDT as well. Notably, PTT-induced hyperthermia can further enhance the CDT effect, achieving a synergistic PTT/CDT therapy. Due to the enhanced permeability and retention (EPR) effect and the high GSH microenvironment of the tumor, IR-FE-Fc@DSPE-S-S-PEG exhibited much higher tumor accumulation revealed by NIR-II fluorescence imaging. More importantly, IR-FE-Fc@DSPE-S-S-PEG efficiently damages tumorous tissues without inducing side effects to normal tissues under 808 nm laser irradiation. This work has proposed an alternative PTT-CDT combined therapy platform based on a rational design of disintegrable NIR-II fluorescence imaging-guided molecular for effective tumor treatment.

Characterizing a photoacoustic and fluorescence imaging platform for preclinical murine longitudinal studies.

To effectively study preclinical animal models, medical imaging technology must be developed with a high enough resolution and sensitivity to perform anatomical, functional, and molecular assessments. Photoacoustic (PA) tomography provides high resolution and specificity, and fluorescence (FL) molecular tomography provides high sensitivity; the combination of these imaging modes will enable a wide range of research applications to be studied in small animals. We introduce and characterize a dual-modality PA and FL imaging platform using in vivo and phantom experiments. The imaging platform's detection limits were characterized through phantom studies that determined the PA spatial resolution, PA sensitivity, optical spatial resolution, and FL sensitivity. The system characterization yielded a PA spatial resolution of in the transverse plane and in the longitudinal axis, a PA sensitivity detection limit not less than that of a sample with absorption coefficient , an optical spatial resolution of in the vertical axis and in the horizontal axis, and a FL sensitivity detection limit not concentration of IR-800. The scanned animals displayed in three-dimensional renders showed high-resolution anatomical detail of organs. The combined PA and FL imaging system has been characterized and has demonstrated its ability to image mice in vivo, proving its suitability for biomedical imaging research applications.

Self-assembled DNA nanoparticles enable cascade circuits for mRNA detection and imaging in living cells

Fluorescence molecular probes have been regarded as a valuable tool for RNA detection and imaging. However, the pivotal challenge is how to develop an efficient fluorescence imaging platform for accurate identification of RNA molecules with low expression in complicated physiological environments. Herein, we construct the DNA nanoparticles to glutathione (GSH)-responsive controllable release of hairpin reactants for catalytic hairpin assembly (CHA)-hybridization chain reaction (HCR) cascade circuits, which enables the analysis and imaging of low-abundance target mRNA in living cells. The aptamer-tethered DNA nanoparticles are constructed via the self-assembly of single-stranded DNAs (ssDNAs), exhibiting sufficient stability, cell-specific penetration, and precise controllability. Moreover, the in-depth integration of different DNA cascade circuits shows the improved sensing performance of DNA nanoparticles in live cell analysis. Therefore, through the combination of multi-amplifiers and programmable DNA nanostructure, the developed strategy enables accurately triggered release of hairpin reactants and further achieves sensitive imaging and quantitative evaluation of survivin mRNA in carcinoma cells, which provides a potential platform to facilitate RNA fluorescence imaging applications in early clinical cancer theranostics.

Ex vivo Drug Sensitivity Imaging-based Platform for Primary Acute Lymphoblastic Leukemia Cells.

Resistance of acute lymphoblastic leukemia (ALL) cells to chemotherapy, whether present at diagnosis or acquired during treatment, is a major cause of treatment failure. Primary ALL cells are accessible for drug sensitivity testing at the time of new diagnosis or at relapse, but there are major limitations with current methods for determining drug sensitivity ex vivo. Here, we describe a functional precision medicine method using a fluorescence imaging platform to test drug sensitivity profiles of primary ALL cells. Leukemia cells are co-cultured with mesenchymal stromal cells and tested with a panel of 40 anti-leukemia drugs to determine individual patterns of drug resistance and sensitivity ("pharmacotype"). This imaging-based pharmacotyping assay addresses the limitations of prior ex vivo drug sensitivity methods by automating data analysis to produce high-throughput data while requiring fewer cells and significantly decreasing the labor-intensive time required to conduct the assay. The integration of drug sensitivity data with genomic profiling provides a basis for rational genomics-guided precision medicine. Key features Analysis of primary acute lymphoblastic leukemia (ALL) blasts obtained at diagnosis from bone marrow aspirate or peripheral blood. Experiments are performed ex vivo with mesenchymal stromal cell co-culture and require four days to complete. This fluorescence imaging-based protocol enhances previous ex vivo drug sensitivity assays and improves efficiency by requiring fewer primary cells while increasing the number of drugs tested to 40. It takes approximately 2-3 h for sample preparation and processing and a 1.5-hour imaging time. Graphical overview.

Trident: A dual oxygenation and fluorescence imaging platform for real-time and quantitative surgical guidance

Despite recent technological progress in surgical guidance, current intraoperative assessment of tissue that should be removed (e.g., cancer) or avoided (e.g., nerves) is still performed subjectively. Optical imaging is a non-contact, non-invasive modality that has the potential to provide feedback regarding the condition of living tissues by imaging either an exogenously administered contrast agent or endogenous constituents such as hemoglobin, water, and lipids. As such, optical imaging is an attractive modality to provide physiologically and structurally relevant information for decision-making in real-time during surgery. The Trident imaging platform has been designed for real-time surgical guidance using state-of-the-art optical imaging. This platform is capable of dual exogenous and endogenous imaging owing to a unique filter and source combination, allowing to take advantage of both imaging modalities. This platform makes use of a real-time and quantitative imaging method working in the spatial frequency domain, called Single Snapshot imaging of Optical Properties (SSOP). The Trident imaging platform is designed to comply with all relevant standards for clinical use. In this manuscript, we first introduce the rationale for developing the Trident imaging platform. We then describe fluorescence and endogenous imaging modalities where we present the details of the design, assess the performance of the platform on the bench. Finally, we perform the validation of the platform during an in vivo preclinical experiment. Altogether, this work lays the foundation for translating state-of-the-art optical imaging technology to the clinic.

3D-Printed Tumor Phantoms for Assessment of In Vivo Fluorescence Imaging Analysis Methods

PurposeInterventional fluorescence imaging is increasingly being utilized to quantify cancer biomarkers in both clinical and preclinical models, yet absolute quantification is complicated by many factors. The use of optical phantoms has been suggested by multiple professional organizations for quantitative performance assessment of fluorescence guidance imaging systems. This concept can be further extended to provide standardized tools to compare and assess image analysis metrics.Procedures3D-printed fluorescence phantoms based on solid tumor models were developed with representative bio-mimicking optical properties. Phantoms were produced with discrete tumors embedded with an NIR fluorophore of fixed concentration and either zero or 3% non-specific fluorophore in the surrounding material. These phantoms were first imaged by two fluorescence imaging systems using two methods of image segmentation, and four assessment metrics were calculated to demonstrate variability in the quantitative assessment of system performance. The same analysis techniques were then applied to one tumor model with decreasing tumor fluorophore concentrations.ResultsThese anatomical phantom models demonstrate the ability to use 3D printing to manufacture anthropomorphic shapes with a wide range of reduced scattering (μs′: 0.24–1.06 mm−1) and absorption (μa: 0.005–0.14 mm−1) properties. The phantom imaging and analysis highlight variability in the measured sensitivity metrics associated with tumor visualization.Conclusions3D printing techniques provide a platform for demonstrating complex biological models that introduce real-world complexities for quantifying fluorescence image data. Controlled iterative development of these phantom designs can be used as a tool to advance the field and provide context for consensus-building beyond performance assessment of fluorescence imaging platforms, and extend support for standardizing how quantitative metrics are extracted from imaging data and reported in literature.

Can Laser-Assisted Indocyanine Green Angiography Be Used to Quantify Perfusion Changes During Staged Fixation of Pilon Fractures? A Pilot Study.

To quantify soft tissue perfusion changes in pilon fractures during staged treatment using laser-assisted indocyanine green angiography (LA-ICGA). Level 1 trauma center. Prospective cohort study. Twelve patients with 12 pilon fractures participated in the study. Seven patients had OTA/AO classification of 43-C3, 3 had 43-C2, and 2 had 43-B2. LA-ICGA was performed with the SPY fluorescence imaging platform. Analysis via ImageJ was used to generate a fractional area of perfusion (FAP) based on fluorescent intensity to objectively quantify soft tissue perfusion. Anterior, medial, and lateral measurements were performed at the time of initial external fixation (EF) application and then at the time of definitive fixation. FAP within the region of interest was on average 64% medially, 61% laterally, and 62% anteriorly immediately before EF placement. Immediately before definitive open reduction internal fixation, fractional region of interest perfusion was on average 86% medially, 87% laterally, and 86% anteriorly. FAP increased on average 24% medially ( P = 0.0004), 26% laterally ( P = 0.001), and 19% anteriorly ( P = 0.002) from the time of initial EF to the time of definitive open reduction and internal fixation. Quantitative improvement in soft tissue perfusion was identified through the course of staged surgical management in pilon fractures. LA-ICGA potentially may be used to determine appropriate timing for definitive surgical intervention based on the readiness of the soft tissue envelope. Ultimately, these findings may influence clinical outcomes with respect to choice of surgical approach, soft tissue management, surgical timing, and wound healing. Diagnostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Live-Cell RNA Imaging with Metabolically Incorporated Fluorescent Nucleosides.

Fluorescence imaging is a powerful method for probing macromolecular dynamics in biological systems; however, approaches for cellular RNA imaging are limited to the investigation of individual RNA constructs or bulk RNA labeling methods compatible primarily with fixed samples. Here, we develop a platform for fluorescence imaging of bulk RNA dynamics in living cells. We show that fluorescent bicyclic and tricyclic cytidine analogues can be metabolically incorporated into cellular RNA by overexpression of uridine-cytidine kinase 2. In particular, metabolic feeding with the tricyclic cytidine-derived nucleoside tC combined with confocal imaging enables the investigation of RNA synthesis, degradation, and trafficking at single-cell resolution. We apply our imaging modality to study RNA metabolism and localization during the oxidative stress response and find that bulk RNA turnover is greatly accelerated upon NaAsO2 treatment. Furthermore, we identify cytoplasmic RNA granules containing RNA transcripts generated during oxidative stress that are distinct from canonical stress granules and P-bodies and co-localize with the RNA helicase DDX6. Taken together, our work provides a powerful approach for live-cell RNA imaging and reveals how cells reshape RNA transcriptome dynamics in response to oxidative stress.

Tumor-microenvironment triggered signal-to-noise boosting nanoprobes for NIR-IIb fluorescence imaging guided tumor surgery and NIR-II photothermal therapy

High quantum yield quantum dots (QDs) with the emission in the sub-second near infrared window (NIR-IIb, 1500–1700 nm) can afford higher resolution, a deeper penetration depth and zero auto-fluorescence for bio-imaging. However, low tumor accumulation, the rapid renal clearance and potential toxicity impeding their biomedical applications. Here, we report a tumor microenvironment responsive hollowed virus-bionic MnO2 nanoshell with IR1061 loading in the cavity and QDs (PbS@CdS) anchoring on the surface for precise NIR-IIb fluorescence imaging guided tumor surgery and efficient NIR-II photothermal therapy. This QDs based nanoprobe could efficiently adhere on tumor cells to realize efficient tumor tissue accumulation. NIR-IIb fluorescence of tumor margin could be successfully delineating after extracellular weak acid triggered MnO2 biodegradation for IR1061 release with remarkable NIR-IIb signal-to-noise boosting. Then, it could facilitate complete dissection of various tumor models with the assistance of NIR-IIb fluorescence imaging. Moreover, the fascinating efficacy for micro-metastasis eradication via NIR-II photothermal effects can be achieved under NIR-IIb fluorescence imaging guidance. Specifically, in combination with negligible system toxicity, our nanoprobes showed great potential as a versatile NIR-IIb fluorescent imaging platform for precise tumor surgery and tumor therapy guidance for future clinical translation.

Abstract 454: TumorMapr™ analytical software platform: Unbiased spatial analytics and explainable AI (xAI) platform for generating data, extracting information, and creating knowledge from multi to hyperplexed fluorescence and/or mass spectrometry image datasets

Abstract Background: The current computational analyses of multi to hyperplexed fluorescence and/or mass spectrometry image datasets from patient pathology samples are not powerful enough to extract the maximum amount of information or to create the detailed knowledge that is required to advance precision medicine in pathology, including the development of personalized therapeutic strategies, identification of potential novel targets for drug discovery, selection of optimal patient cohorts for clinical trials, and improvement of the predictive power of prognostics/diagnostics. Methods: TumorMapr harnesses the computational power of proprietary, unbiased spatial analytics, spatial systems pathology, and explainable artificial intelligence (xAI) to extract information and to create knowledge from patient primary disease pathology samples imaged on any of the existing fluorescence and/or mass spectrometry imaging platforms. Results: To demonstrate the generalizability and utility of the TumorMapr platform, we apply it on two different datasets: hyperplexed immunofluorescence-based colorectal cancer data (51 biomarkers, 431 patients) and imaging mass cytometry-based breast cancer data (35 biomarkers, 281 patients). The TumorMapr platform (i) unlike the biased intensity thresholding approaches, the unbiased and automated functional cell phenotyping discovers a continuum of cell types and cell states, including transitional, multi-transitional cell states and fusion cell types that are critical for disease progression; (ii) derives microdomains with tumor promoting and tumor suppressing properties that are highly predictive of disease progression and response to therapy; (iii) spatial systems pathology analysis taps into the current network biology knowledge databases to derive pathway interactions and signaling networks, identify novel biomarkers and potential molecular targets and drugs, in the spatial context of each microdomain; (iv) xAI application guide, for example, in the case of predicting 5-year risk of recurrence in CRC patients, provides explanations in the form of microdomain-specific networks that are driving disease progression. Using the TumorMapr pipeline we created a prognostic test that shows a vastly superior performance over current approaches in predicting 5-yr risk of recurrence in CRC patients. Further, the TumorMapr platform enables building a rich outcome-specific library of microdomains to directly apply on prospective tissue samples for a companion diagnostic test that predicts disease outcomes. Citation Format: Samantha Panakkal, Brian Falkenstein, Akif Burak Tosun, Bruce Campbell, Michael Becich, Jeffrey Fine, D. Lansing Taylor, S. Chakra Chennubhotla, Filippo Pullara. TumorMapr™ analytical software platform: Unbiased spatial analytics and explainable AI (xAI) platform for generating data, extracting information, and creating knowledge from multi to hyperplexed fluorescence and/or mass spectrometry image datasets [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 454.

Dual-Wavelength Photoacoustic Computed Tomography with Piezoelectric Ring-Array Transducer for Imaging of Indocyanine Green Liposomes Aggregation in Tumors.

Recently, indocyanine green (ICG), as an FDA-approved dye, has been widely used for phototherapy. It is essential to obtain information on the migration and aggregation of ICG in deep tissues. However, existing fluorescence imaging platforms are not able to obtain the structural information of the tissues. Here, we prepared ICG liposomes (ICG-Lips) and built a dual-wavelength photoacoustic computed tomography (PACT) system with piezoelectric ring-array transducer to image the aggregation of ICG-Lips in tumors to guide phototherapy. Visible 780 nm light excited the photoacoustic (PA) effects of the ICG-Lips and near-infrared 1064 nm light provided the imaging of the surrounding tissues. The aggregation of ICG-Lips within the tumor and the surrounding tissues was visualized by PACT in real time. This work indicates that PACT with piezoelectric ring-array transducer has great potential in the real-time monitoring of in vivo drug distribution.