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Williams AL, Scorzo AV, Strawbridge RR, Davis SC, Niedre M. Two-color diffuse in vivo flow cytometer. JOURNAL OF BIOMEDICAL OPTICS 2024; 29:065003. [PMID: 38818515 PMCID: PMC11138342 DOI: 10.1117/1.jbo.29.6.065003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/05/2024] [Revised: 04/26/2024] [Accepted: 05/14/2024] [Indexed: 06/01/2024]
Abstract
Significance Hematogenous metastasis is mediated by circulating tumor cells (CTCs) and CTC clusters (CTCCs). We recently developed "diffuse in vivo flow cytometry" (DiFC) to detect fluorescent protein (FP) expressing CTCs in small animals. Extending DiFC to allow detection of two FPs simultaneously would allow concurrent study of different CTC sub-populations or heterogeneous CTCCs in the same animal. Aim The goal of this work was to develop and validate a two-color DiFC system capable of non-invasively detecting circulating cells expressing two distinct FPs. Approach A DiFC instrument was designed and built to detect cells expressing either green FP (GFP) or tdTomato. We tested the instrument in tissue-mimicking flow phantoms in vitro and in multiple myeloma bearing mice in vivo. Results In phantoms, we could accurately differentiate GFP+ and tdTomato+ CTCs and CTCCs. In tumor-bearing mice, CTC numbers expressing both FPs increased during disease. Most CTCCs (86.5%) expressed single FPs with the remainder both FPs. These data were supported by whole-body hyperspectral fluorescence cryo-imaging of the mice. Conclusions We showed that two-color DiFC can detect two populations of CTCs and CTCCs concurrently. This instrument could allow study of tumor development and response to therapies for different sub-populations in the same animal.
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Affiliation(s)
- Amber L. Williams
- Northeastern University, Department of Bioengineering, Boston, Massachusetts, United States
| | - Augustino V. Scorzo
- Dartmouth College, Thayer School of Engineering, Hanover, New Hampshire, United States
| | | | - Scott C. Davis
- Dartmouth College, Thayer School of Engineering, Hanover, New Hampshire, United States
| | - Mark Niedre
- Northeastern University, Department of Bioengineering, Boston, Massachusetts, United States
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Pace J, Lee JJ, Srinivasarao M, Kallepu S, Low PS, Niedre M. In Vivo Labeling and Detection of Circulating Tumor Cells in Mice Using OTL38. Mol Imaging Biol 2024:10.1007/s11307-024-01914-0. [PMID: 38594545 DOI: 10.1007/s11307-024-01914-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2023] [Revised: 03/04/2024] [Accepted: 03/30/2024] [Indexed: 04/11/2024]
Abstract
PURPOSE We recently developed an optical instrument to non-invasively detect fluorescently labeled circulating tumor cells (CTCs) in mice called 'Diffuse in vivo Flow Cytometry' (DiFC). OTL38 is a folate receptor (FR) targeted near-infrared (NIR) contrast agent that is FDA approved for use in fluorescence guided surgery of ovarian and lung cancer. In this work, we investigated the use OTL38 for in vivo labeling and detection of FR + CTCs with DiFC. PROCEDURES We tested OTL38 labeling of FR + cancer cell lines (IGROV-1 and L1210A) as well as FR- MM.1S cells in suspensions of Human Peripheral Blood Mononuclear cells (PBMCs) in vitro. We also tested OTL38 labeling and NIR-DIFC detection of FR + L1210A cells in blood circulation in nude mice in vivo. RESULTS 62% of IGROV-1 and 83% of L1210A were labeled above non-specific background levels in suspensions of PBMCs in vitro compared to only 2% of FR- MM.1S cells. L1210A cells could be labeled with OTL38 directly in circulation in vivo and externally detected using NIR-DiFC in mice with low false positive detection rates. CONCLUSIONS This work shows the feasibility of labeling CTCs in vivo with OTL38 and detection with DiFC. Although further refinement of the DiFC instrument and signal processing algorithms and testing with other animal models is needed, this work may eventually pave the way for human use of DiFC.
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Affiliation(s)
- Joshua Pace
- Department of Bioengineering, Northeastern University, Boston, MA, 02115, USA
| | - Jane J Lee
- Department of Bioengineering, Northeastern University, Boston, MA, 02115, USA
| | | | | | - Philip S Low
- Department of Chemistry, Purdue University, West Lafayette, IN, 047906, USA
| | - Mark Niedre
- Department of Bioengineering, Northeastern University, Boston, MA, 02115, USA.
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3
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Pace J, Ivich F, Marple E, Niedre M. Near-infrared diffuse in vivo flow cytometry. JOURNAL OF BIOMEDICAL OPTICS 2022; 27:JBO-220101GR. [PMID: 36114606 PMCID: PMC9478904 DOI: 10.1117/1.jbo.27.9.097002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2022] [Accepted: 09/07/2022] [Indexed: 06/15/2023]
Abstract
Significance Diffuse in vivo flow cytometry (DiFC) is an emerging technique for enumerating rare fluorescently labeled circulating cells noninvasively in the bloodstream. Thus far, we have reported red and blue-green versions of DiFC. Use of near-infrared (NIR) fluorescent light would in principle allow use of DiFC in deeper tissues and would be compatible with emerging NIR fluorescence molecular contrast agents. Aim We describe the design of a NIR-DiFC instrument and demonstrate its use in optical flow phantoms in vitro and in mice in vivo. Approach We developed an improved optical fiber probe design for efficient collection of fluorescence from individual circulating cells and efficient rejection of instrument autofluorescence. We built a NIR-DiFC instrument. We tested this with NIR fluorescent microspheres and cell lines labeled with OTL38 fluorescence contrast agent in a flow phantom model. We also tested NIR-DiFC in nude mice injected intravenously with OTL38-labeled L1210A cells. Results NIR-DiFC allowed detection of circulating tumor cells (CTCs) in flow phantoms with mean signal-to-noise ratios (SNRs) of 19 to 32 dB. In mice, fluorescently labeled CTCs were detectable with mean SNR of 26 dB. NIR-DiFC also exhibited orders significantly lower autofluorescence and false-alarm rates than blue-green DiFC. Conclusions NIR-DiFC allows use of emerging NIR contrast agents. Our work could pave the way for future use of NIR-DiFC in humans.
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Affiliation(s)
- Joshua Pace
- Northeastern University, Department of Bioengineering, Boston, Massachusetts, United States
| | - Fernando Ivich
- Northeastern University, Department of Bioengineering, Boston, Massachusetts, United States
| | - Eric Marple
- EmVision LLC, Loxahatchee, Florida, United States
| | - Mark Niedre
- Northeastern University, Department of Bioengineering, Boston, Massachusetts, United States
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Vora N, Shekhar P, Esmail M, Patra A, Georgakoudi I. Label-free flow cytometry of rare circulating tumor cell clusters in whole blood. Sci Rep 2022; 12:10721. [PMID: 35750889 PMCID: PMC9232518 DOI: 10.1038/s41598-022-14003-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Accepted: 05/31/2022] [Indexed: 11/09/2022] Open
Abstract
Circulating tumor cell clusters (CTCCs) are rare cellular events found in the blood stream of metastatic tumor patients. Despite their scarcity, they represent an increased risk for metastasis. Label-free detection methods of these events remain primarily limited to in vitro microfluidic platforms. Here, we expand on the use of confocal backscatter and fluorescence flow cytometry (BSFC) for label-free detection of CTCCs in whole blood using machine learning for peak detection/classification. BSFC uses a custom-built flow cytometer with three excitation wavelengths (405 nm, 488 nm, and 633 nm) and five detectors to detect CTCCs in whole blood based on corresponding scattering and fluorescence signals. In this study, detection of CTCC-associated GFP fluorescence is used as the ground truth to assess the accuracy of endogenous back-scattered light-based CTCC detection in whole blood. Using a machine learning model for peak detection/classification, we demonstrated that the combined use of backscattered signals at the three wavelengths enable detection of ~ 93% of all CTCCs larger than two cells with a purity of > 82% and an overall accuracy of > 95%. The high level of performance established through BSFC and machine learning demonstrates the potential for label-free detection and monitoring of CTCCs in whole blood. Further developments of label-free BSFC to enhance throughput could lead to important applications in the isolation of CTCCs in whole blood with minimal disruption and ultimately their detection in vivo.
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Affiliation(s)
- Nilay Vora
- Department of Biomedical Engineering, Tufts University, Medford, MA, 02155, USA
| | - Prashant Shekhar
- Department of Mathematics, Embry-Riddle Aeronautical University, Daytona Beach, FL, 32114, USA
| | - Michael Esmail
- Tufts Comparative Medicine Services, Tufts University, Medford, MA, 02155, USA
| | - Abani Patra
- Department of Computer Science, Tufts University, Medford, MA, 02155, USA
| | - Irene Georgakoudi
- Department of Biomedical Engineering, Tufts University, Medford, MA, 02155, USA.
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Ivich F, Pace J, Williams AL, Shumel M, Fang Q, Niedre M. Signal and measurement considerations for human translation of diffuse in vivo flow cytometry. JOURNAL OF BIOMEDICAL OPTICS 2022; 27:JBO-220066R. [PMID: 35726129 PMCID: PMC9207655 DOI: 10.1117/1.jbo.27.6.067001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/24/2022] [Accepted: 05/27/2022] [Indexed: 06/15/2023]
Abstract
SIGNIFICANCE "Diffuse in vivo flow cytometry" (DiFC) is an emerging technology for fluorescence detection of rare circulating cells directly in large deep-seated blood vessels in mice. Because DiFC uses highly scattered light, in principle, it could be translated to human use. However, an open question is whether fluorescent signals from single cells would be detectable in human-scale anatomies. AIM Suitable blood vessels in a human wrist or forearm are at a depth of ∼2 to 4 mm. The aim of this work was to study the impact of DiFC instrument geometry and wavelength on the detected DiFC signal and on the maximum depth of detection of a moving cell. APPROACH We used Monte Carlo simulations to compute fluorescence Jacobian (sensitivity) matrices for a range of source and detector separations (SDS) and tissue optical properties over the visible and near infrared spectrum. We performed experimental measurements with three available versions of DiFC (488, 640, and 780 nm), fluorescent microspheres, and tissue mimicking optical flow phantoms. We used both computational and experimental data to estimate the maximum depth of detection at each combination of settings. RESULTS For the DiFC detection problem, our analysis showed that for deep-seated blood vessels, the maximum sensitivity was obtained with NIR light (780 nm) and 3-mm SDS. CONCLUSIONS These results suggest that-in combination with a suitable molecularly targeted fluorescent probes-circulating cells and nanosensors could, in principle, be detectable in circulation in humans.
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Affiliation(s)
- Fernando Ivich
- Northeastern University, Department of Bioengineering, Boston, Massachusetts, United States
| | - Joshua Pace
- Northeastern University, Department of Bioengineering, Boston, Massachusetts, United States
| | - Amber L. Williams
- Northeastern University, Department of Bioengineering, Boston, Massachusetts, United States
| | - Malcolm Shumel
- Northeastern University, Department of Bioengineering, Boston, Massachusetts, United States
| | - Qianqian Fang
- Northeastern University, Department of Bioengineering, Boston, Massachusetts, United States
| | - Mark Niedre
- Northeastern University, Department of Bioengineering, Boston, Massachusetts, United States
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6
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Towards rainbow portable Cytophone with laser diodes for global disease diagnostics. Sci Rep 2022; 12:8671. [PMID: 35606373 PMCID: PMC9126638 DOI: 10.1038/s41598-022-11452-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Accepted: 04/18/2022] [Indexed: 11/08/2022] Open
Abstract
In vivo, Cytophone has demonstrated the capability for the early diagnosis of cancer, infection, and cardiovascular disorders through photoacoustic detection of circulating disease markers directly in the bloodstream with an unprecedented 1,000-fold improvement in sensitivity. Nevertheless, a Cytophone with higher specificity and portability is urgently needed. Here, we introduce a novel Cytophone platform that integrates a miniature multispectral laser diode array, time-color coding, and high-speed time-resolved signal processing. Using two-color (808 nm/915 nm) laser diodes, we demonstrated spectral identification of white and red clots, melanoma cells, and hemozoin in malaria-infected erythrocytes against a blood background and artifacts. Data from a Plasmodium yoelii murine model and cultured human P. falciparum were verified in vitro with confocal photothermal and fluorescent microscopy. With these techniques, we detected infected cells within 4 h after invasion, which makes hemozoin promising as a spectrally selective marker at the earliest stages of malaria progression. Along with the findings from our previous application of Cytophone with conventional lasers for the diagnosis of melanoma, bacteremia, sickle anemia, thrombosis, stroke, and abnormal hemoglobin forms, this current finding suggests the potential for the development of a portable rainbow Cytophone with multispectral laser diodes for the identification of these and other diseases.
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Patil RA, Srinivasarao M, Amiji MM, Low PS, Niedre M. Fluorescence Labeling of Circulating Tumor Cells with a Folate Receptor-Targeted Molecular Probe for Diffuse In Vivo Flow Cytometry. Mol Imaging Biol 2021; 22:1280-1289. [PMID: 32519245 DOI: 10.1007/s11307-020-01505-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
PURPOSE We recently developed a new instrument called "diffuse in vivo flow cytometry" (DiFC) for enumeration of rare fluorescently labeled circulating tumor cells (CTCs) in small animals without drawing blood samples. Until now, we have used cell lines that express fluorescent proteins or were pre-labeled with a fluorescent dye ex vivo. In this work, we investigated the use of a folate receptor (FR)-targeted fluorescence molecular probe for in vivo labeling of FR+ CTCs for DiFC. PROCEDURES We used EC-17, a FITC-folic acid conjugate that has been used in clinical trials for fluorescence-guided surgery. We studied the affinity of EC-17 for FR+ L1210A and KB cancer cells. We also tested FR- MM.1S cells. We tested the labeling specificity in cells in culture in vitro and in whole blood. We also studied the detectability of labeled cells in mice in vivo with DiFC. RESULTS EC-17 showed a high affinity for FR+ L1210A and KB cells in vitro. In whole blood, 85.4 % of L1210A and 80.9 % of KB cells were labeled above non-specific background with EC-17, and negligible binding to FR- MM.1S cells was observed. In addition, EC-17-labeled CTCs were readily detectable in circulation in mice with DiFC. CONCLUSIONS This work demonstrates the feasibility of labeling CTCs with a cell-surface receptor-targeted probe for DiFC, greatly expanding the potential utility of the method for pre-clinical animal models. Because DiFC uses diffuse light, this method could be also used to enumerate CTCs in larger animal models and potentially even in humans.
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Affiliation(s)
- Roshani A Patil
- Department of Bioengineering, Northeastern University, Boston, MA, 02115, USA
| | | | - Mansoor M Amiji
- Department of Pharmaceutical Sciences, School of Pharmacy, Northeastern University, Boston, MA, 02115, USA
| | - Philip S Low
- Department of Chemistry, Purdue University, West Lafayette, IN, 47906, USA
| | - Mark Niedre
- Department of Bioengineering, Northeastern University, Boston, MA, 02115, USA.
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Abstract
In vivo flow cytometry (IVFC) was first designed to detect circulating cells in a mouse ear. It allows real-time monitoring of cells in peripheral blood with no need to draw blood. The IVFC field has made great progress during the last decade with the development of fluorescence, photoacoustic, and multiphoton microscopy. Moreover, the application of IVFC is no longer restricted to circulating cells. IVFC based on fluorescence and photoacoustic are most widely applied in biomedical research. Methods based on fluorescence are often used for object monitoring in superficial vessels, while methods based on photoacoustics have an advantage of label-free monitoring in deep vessels. In this chapter, we introduce technical points and key applications of IVFC. We focus on the principles, labeling strategies, sensitivity, and biomedical applications of the technology. In addition, we summarize this chapter and discuss important research directions of IVFC in the future.
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Zhu X, Suo Y, Fu Y, Zhang F, Ding N, Pang K, Xie C, Weng X, Tian M, He H, Wei X. In vivo flow cytometry reveals a circadian rhythm of circulating tumor cells. LIGHT, SCIENCE & APPLICATIONS 2021; 10:110. [PMID: 34045431 PMCID: PMC8160330 DOI: 10.1038/s41377-021-00542-5] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Revised: 04/21/2021] [Accepted: 04/21/2021] [Indexed: 05/13/2023]
Abstract
Circulating tumor cells (CTCs) is an established biomarker of cancer metastasis. The circulation dynamics of CTCs are important for understanding the mechanisms underlying tumor cell dissemination. Although studies have revealed that the circadian rhythm may disrupt the growth of tumors, it is generally unclear whether the circadian rhythm controls the release of CTCs. In clinical examinations, the current in vitro methods for detecting CTCs in blood samples are based on a fundamental assumption that CTC counts in the peripheral blood do not change significantly over time, which is being challenged by recent studies. Since it is not practical to draw blood from patients repeatedly, a feasible strategy to investigate the circadian rhythm of CTCs is to monitor them by in vivo detection methods. Fluorescence in vivo flow cytometry (IVFC) is a powerful optical technique that is able to detect fluorescent circulating cells directly in living animals in a noninvasive manner over a long period of time. In this study, we applied fluorescence IVFC to monitor CTCs noninvasively in an orthotopic mouse model of human prostate cancer. We observed that CTCs exhibited stochastic bursts over cancer progression. The probability of the bursting activity was higher at early stages than at late stages. We longitudinally monitored CTCs over a 24-h period, and our results revealed striking daily oscillations in CTC counts that peaked at the onset of the night (active phase for rodents), suggesting that the release of CTCs might be regulated by the circadian rhythm.
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Affiliation(s)
- Xi Zhu
- State Key Laboratory of Oncogenes and Related Genes, Shanghai Cancer Institute, Med-X Research Institute and School of Biomedical Engineering, Shanghai Jiao Tong University, 200030, Shanghai, China
| | - Yuanzhen Suo
- Biomedical Pioneering Innovation Center, Peking University, 100871, Beijing, China.
- School of Life Sciences, Peking University, 100871, Beijing, China.
| | - Yuting Fu
- State Key Laboratory of Oncogenes and Related Genes, Shanghai Cancer Institute, Med-X Research Institute and School of Biomedical Engineering, Shanghai Jiao Tong University, 200030, Shanghai, China
| | - Fuli Zhang
- State Key Laboratory of Oncogenes and Related Genes, Shanghai Cancer Institute, Med-X Research Institute and School of Biomedical Engineering, Shanghai Jiao Tong University, 200030, Shanghai, China
| | - Nan Ding
- State Key Laboratory of Oncogenes and Related Genes, Shanghai Cancer Institute, Med-X Research Institute and School of Biomedical Engineering, Shanghai Jiao Tong University, 200030, Shanghai, China
| | - Kai Pang
- School of Instrument Science and Optoelectronics Engineering, Beijing Information Science and Technology University, 100192, Beijing, China
| | - Chengying Xie
- State Key Laboratory of Oncogenes and Related Genes, Shanghai Cancer Institute, Med-X Research Institute and School of Biomedical Engineering, Shanghai Jiao Tong University, 200030, Shanghai, China
| | - Xiaofu Weng
- State Key Laboratory of Oncogenes and Related Genes, Shanghai Cancer Institute, Med-X Research Institute and School of Biomedical Engineering, Shanghai Jiao Tong University, 200030, Shanghai, China
| | - Meilu Tian
- Biomedical Engineering Department, Peking University, 100081, Beijing, China
| | - Hao He
- State Key Laboratory of Oncogenes and Related Genes, Shanghai Cancer Institute, Med-X Research Institute and School of Biomedical Engineering, Shanghai Jiao Tong University, 200030, Shanghai, China.
| | - Xunbin Wei
- State Key Laboratory of Oncogenes and Related Genes, Shanghai Cancer Institute, Med-X Research Institute and School of Biomedical Engineering, Shanghai Jiao Tong University, 200030, Shanghai, China.
- Biomedical Engineering Department, Peking University, 100081, Beijing, China.
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Peking University Cancer Hospital and Institute, 100142, Beijing, China.
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Williams AL, Fitzgerald JE, Ivich F, Sontag ED, Niedre M. Short-Term Circulating Tumor Cell Dynamics in Mouse Xenograft Models and Implications for Liquid Biopsy. Front Oncol 2020; 10:601085. [PMID: 33240820 PMCID: PMC7677561 DOI: 10.3389/fonc.2020.601085] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Accepted: 10/14/2020] [Indexed: 12/13/2022] Open
Abstract
MOTIVATION Circulating tumor cells (CTCs) are widely studied using liquid biopsy methods that analyze fractionally-small peripheral blood (PB) samples. However, little is known about natural fluctuations in CTC numbers that may occur over short timescales in vivo, and how these may affect detection and enumeration of rare CTCs from small blood samples. METHODS We recently developed an optical instrument called "diffuse in vivo flow cytometry" (DiFC) that uniquely allows continuous, non-invasive counting of rare, green fluorescent protein expressing CTCs in large blood vessels in mice. Here, we used DiFC to study short-term changes in CTC numbers in multiple myeloma and Lewis lung carcinoma xenograft models. We analyzed CTC detections in over 100 h of DiFC data, and considered intervals corresponding to approximately 1%, 5%, 10%, and 20% of the PB volume. In addition, we analyzed changes in CTC numbers over 24 h (diurnal) periods. RESULTS For rare CTCs (fewer than 1 CTC per ml of blood), the use of short DiFC intervals (corresponding to small PB samples) frequently resulted in no detections. For more abundant CTCs, CTC numbers frequently varied by an order of magnitude or more over the time-scales considered. This variance in CTC detections far exceeded that expected by Poisson statistics or by instrument variability. Rather, the data were consistent with significant changes in mean numbers of CTCs on the timescales of minutes and hours. CONCLUSIONS The observed temporal changes can be explained by known properties of CTCs, namely, the continuous shedding of CTCs from tumors and the short half-life of CTCs in blood. It follows that the number of cells in a blood sample are strongly impacted by the timing of the draw. The issue is likely to be compounded for multicellular CTC clusters or specific CTC subtypes, which are even more rare than single CTCs. However, we show that enumeration can in principle be improved by averaging multiple samples, analysis of larger volumes, or development of methods for enumeration of CTCs directly in vivo.
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Affiliation(s)
- Amber L. Williams
- Department of Bioengineering, Northeastern University, Boston, MA, United States
| | | | - Fernando Ivich
- Department of Bioengineering, Northeastern University, Boston, MA, United States
| | - Eduardo D. Sontag
- Department of Bioengineering, Northeastern University, Boston, MA, United States
- Department of Electrical and Computer Engineering, Northeastern University, Boston, MA, United States
- Laboratory of Systems Pharmacology, Harvard Medical School, Boston, MA, United States
| | - Mark Niedre
- Department of Bioengineering, Northeastern University, Boston, MA, United States
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Tian C, Xu X, Wang Y, Li D, Lu H, Yang Z. Development and Clinical Prospects of Techniques to Separate Circulating Tumor Cells from Peripheral Blood. Cancer Manag Res 2020; 12:7263-7275. [PMID: 32884342 PMCID: PMC7434565 DOI: 10.2147/cmar.s248380] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2020] [Accepted: 07/15/2020] [Indexed: 12/15/2022] Open
Abstract
Detection of circulating tumor cells (CTC) is an important liquid biopsy technique that has advanced considerably in recent years. To further advance the development of technology for curing cancer, several CTC technologies have been proposed by various research groups. Despite their potential role in early cancer diagnosis and prognosis, CTC methods are currently used for research purposes only, and very few methods have been accepted for clinical applications because of difficulties, including CTC heterogeneity, CTC separation from the blood, and a lack of thorough clinical validation. Although current CTC technologies have not been truly implemented, they possess high potential as future clinical diagnostic techniques for individualized cancer. Here, we review current developments in CTC separation technology. We also explore new CTC detection methods based on telomerase and nanomaterials, such as in vivo flow cytometry. In addition, we discuss the difficulties that must be overcome before CTC can be applied in clinical settings.
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Affiliation(s)
- Cheng Tian
- Yichang Central People's Hospital, First Clinical Medical College of Three Gorges University, Yichang 443000, People's Republic of China
| | - Xinhua Xu
- Yichang Central People's Hospital, First Clinical Medical College of Three Gorges University, Yichang 443000, People's Republic of China
| | - Yuke Wang
- Yichang Central People's Hospital, First Clinical Medical College of Three Gorges University, Yichang 443000, People's Republic of China
| | - Dailong Li
- Yichang Central People's Hospital, First Clinical Medical College of Three Gorges University, Yichang 443000, People's Republic of China
| | - Haiyan Lu
- Yichang Central People's Hospital, First Clinical Medical College of Three Gorges University, Yichang 443000, People's Republic of China
| | - Ziwei Yang
- Yichang Central People's Hospital, First Clinical Medical College of Three Gorges University, Yichang 443000, People's Republic of China
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12
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Fitzgerald JE, Byrd BK, Patil RA, Strawbridge RR, Davis SC, Bellini C, Niedre M. Heterogeneity of circulating tumor cell dissemination and lung metastases in a subcutaneous Lewis lung carcinoma model. BIOMEDICAL OPTICS EXPRESS 2020; 11:3633-3647. [PMID: 33014556 PMCID: PMC7510907 DOI: 10.1364/boe.395289] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2020] [Revised: 05/26/2020] [Accepted: 05/31/2020] [Indexed: 05/07/2023]
Abstract
Subcutaneous (s.c.) tumor models are widely used in pre-clinical cancer metastasis research. Despite this, the dynamics and natural progression of circulating tumor cells (CTCs) and CTC clusters (CTCCs) in peripheral blood are poorly understood in these models. In this work, we used a new technique called 'diffuse in vivo flow cytometry' (DiFC) to study CTC and CTCC dissemination in an s.c. Lewis lung carcinoma (LLC) model in mice. Tumors were grown in the rear flank and we performed DiFC up to 31 days after inoculation. At the study endpoint, lungs were excised and bioluminescence imaging (BLI) was performed to determine the extent of lung metastases. We also used fluorescence macro-cryotome imaging to visualize infiltration and growth of the primary tumor. DiFC revealed significant heterogeneity in CTC and CTCC numbers amongst all mice studied, despite using clonally identical LLC cells and tumor placement. Maximum DiFC count rates corresponded to 0.1 to 14 CTCs per mL of peripheral blood. In general, CTC numbers did not necessarily increase monotonically over time and were poorly correlated with tumor volume. However, there was a good correlation between CTC and CTCC numbers in peripheral blood and lung metastases. We attribute the differences in CTC numbers primarily due to growth patterns of the primary tumor. This study is one of the few reports of CTC shedding dynamics in sub-cutaneous metastasis models and underscores the value of in vivo methods for continuous, non-invasive CTC monitoring.
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Affiliation(s)
- Jessica E. Fitzgerald
- Department of Bioengineering, Northeastern University, 360 Huntington Avenue, Boston, MA 02115, USA
| | - Brook K. Byrd
- Thayer School of Engineering, Dartmouth College, 14 Engineering Drive, Hanover, NH 03755, USA
| | - Roshani A. Patil
- Department of Bioengineering, Northeastern University, 360 Huntington Avenue, Boston, MA 02115, USA
| | - Rendall R. Strawbridge
- Thayer School of Engineering, Dartmouth College, 14 Engineering Drive, Hanover, NH 03755, USA
| | - Scott C. Davis
- Thayer School of Engineering, Dartmouth College, 14 Engineering Drive, Hanover, NH 03755, USA
| | - Chiara Bellini
- Department of Bioengineering, Northeastern University, 360 Huntington Avenue, Boston, MA 02115, USA
| | - Mark Niedre
- Department of Bioengineering, Northeastern University, 360 Huntington Avenue, Boston, MA 02115, USA
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Cao X, Yao C, Jiang S, Gunn J, Van Namen AC, Bruza P, Pogue BW. Time-gated luminescence imaging for background free in vivo tracking of single circulating tumor cells. OPTICS LETTERS 2020; 45:3761-3764. [PMID: 32630948 DOI: 10.1364/ol.391350] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2020] [Accepted: 05/26/2020] [Indexed: 05/20/2023]
Abstract
Fluorescence imaging is severely limited by the background and autofluorescence of tissues for in vivo detection of circulating tumor cells (CTCs). Time-gated luminescence (TGL) imaging, in combination with luminescent probes that possess hundreds of microsecond emission lifetimes, can be used to effectively suppress this background, which has predominantly nanosecond lifetimes. This Letter demonstrates the feasibility of TGL imaging using luminescent probes for the in vivo real time imaging and tracking of single CTCs circulating freely in the blood vessels with higher accuracy given by substantially higher signal-to-noise ratio. The luminescent probe used in this Letter was a commercial Eu3+ chelate (EuC) nanosphere with a super-long lifetime of near 800 µs, which enabled TGL imaging to achieve background-free detection with ∼5 times higher SNR versus steady state. Phantom and in vivo mouse studies indicated that EuC labeled tumor cells moving in medium or bloodstream at the speed of 1-2 mm/s could be captured in real time.
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14
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Mensah SA, Nersesyan AA, Harding IC, Lee CI, Tan X, Banerjee S, Niedre M, Torchilin VP, Ebong EE. Flow-regulated endothelial glycocalyx determines metastatic cancer cell activity. FASEB J 2020; 34:6166-6184. [PMID: 32167209 DOI: 10.1096/fj.201901920r] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Revised: 01/30/2020] [Accepted: 02/22/2020] [Indexed: 12/14/2022]
Abstract
Cancer metastasis and secondary tumor initiation largely depend on circulating tumor cell (CTC) and vascular endothelial cell (EC) interactions by incompletely understood mechanisms. Endothelial glycocalyx (GCX) dysfunction may play a significant role in this process. GCX structure depends on vascular flow patterns, which are irregular in tumor environments. This work presents evidence that disturbed flow (DF) induces GCX degradation, leading to CTC homing to the endothelium, a first step in secondary tumor formation. A 2-fold greater attachment of CTCs to human ECs was found to occur under DF conditions, compared to uniform flow (UF) conditions. These results corresponded to an approximately 50% decrease in wheat germ agglutinin (WGA)-labeled components of the GCX under DF conditions, vs UF conditions, with undifferentiated levels of CTC-recruiting E-selectin under DF vs UF conditions. Confirming the role of the GCX, neuraminidase induced the degradation of WGA-labeled GCX under UF cell culture conditions or in Balb/C mice and led to an over 2-fold increase in CTC attachment to ECs or Balb/C mouse lungs, respectively, compared to untreated conditions. These experiments confirm that flow-induced GCX degradation can enable metastatic CTC arrest. This work, therefore, provides new insight into pathways of secondary tumor formation.
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Affiliation(s)
- Solomon A Mensah
- Department of Bioengineering, Northeastern University, Boston, MA, USA
| | - Alina A Nersesyan
- Department of Bioengineering, Northeastern University, Boston, MA, USA
| | - Ian C Harding
- Department of Bioengineering, Northeastern University, Boston, MA, USA
| | - Claire I Lee
- Department of Bioengineering, Northeastern University, Boston, MA, USA
| | - Xuefei Tan
- Department of Electrical and Computer Engineering, Northeastern University, Boston, MA, USA
| | - Selina Banerjee
- Department of Chemical Engineering, Northeastern University, Boston, MA, USA
| | - Mark Niedre
- Department of Bioengineering, Northeastern University, Boston, MA, USA.,Department of Electrical and Computer Engineering, Northeastern University, Boston, MA, USA
| | | | - Eno E Ebong
- Department of Bioengineering, Northeastern University, Boston, MA, USA.,Department of Chemical Engineering, Northeastern University, Boston, MA, USA.,Neuroscience Department, Albert Einstein College of Medicine, New York, NY, USA
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15
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Bartosik PB, Fitzgerald JE, El Khatib M, Yaseen MA, Vinogradov SA, Niedre M. Prospects for the Use of Upconverting Nanoparticles as a Contrast Agent for Enumeration of Circulating Cells in vivo. Int J Nanomedicine 2020; 15:1709-1719. [PMID: 32210561 PMCID: PMC7074808 DOI: 10.2147/ijn.s243157] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Accepted: 02/20/2020] [Indexed: 12/25/2022] Open
Abstract
PURPOSE We recently developed a new fluorescence-based technique called "diffuse in vivo flow cytometry" (DiFC) for enumerating rare circulating tumor cells (CTCs) directly in the bloodstream. Non-specific tissue autofluorescence is a persistent problem, as it creates a background which may obscure signals from weakly-labeled CTCs. Here we investigated the use of upconverting nanoparticles (UCNPs) as a contrast agent for DiFC, which in principle could significantly reduce the autofluorescence background and allow more sensitive detection of rare CTCs. METHODS We built a new UCNP-compatible DiFC instrument (U-DiFC), which uses a 980 nm laser and detects upconverted luminescence in the 520, 545 and 660 nm emission bands. We used NaYF4:Yb,Er UCNPs and several covalent and non-covalent surface modification strategies to improve their biocompatibility and cell uptake. We tested U-DiFC with multiple myeloma (MM) and Lewis lung carcinoma (LLC) cells in tissue-mimicking optical flow phantoms and in nude mice. RESULTS U-DiFC significantly reduced the background autofluorescence signals and motion artifacts from breathing in mice. Upconverted luminescence from NaYF4:Yb,Er microparticles (UμNP) and cells co-incubated with UCNPs were readily detectable with U-DiFC in phantoms, and from UCNPs in circulation in mice. However, we were unable to achieve reliable labeling of CTCs with UCNPs. Our data suggest that most (or all) of the measured U-DIFC signal in vitro and in vivo likely arose from unbound UCNPs or due to the uptake by non-CTC blood cells. CONCLUSION UCNPs have a number of properties that make them attractive contrast agents for high-sensitivity detection of CTCs in the bloodstream with U-DiFC and other intravital imaging methods. More work is needed to achieve reliable and specific labeling of CTCs with UCNPs and verify long-term retention and viability of cells.
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Affiliation(s)
- Peter B Bartosik
- Department of Bioengineering, Northeastern University, Boston, MA, USA
| | | | - Mirna El Khatib
- Department of Biochemistry and Biophysics, Perelman School of Medicine and Department of Chemistry, School of Arts and Sciences, University of Pennsylvania, Philadelphia, PA, USA
| | - Mohammad A Yaseen
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Charlestown, MA, USA
| | - Sergei A Vinogradov
- Department of Biochemistry and Biophysics, Perelman School of Medicine and Department of Chemistry, School of Arts and Sciences, University of Pennsylvania, Philadelphia, PA, USA
| | - Mark Niedre
- Department of Bioengineering, Northeastern University, Boston, MA, USA
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16
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Kong C, Hu M, Weerakoon-Ratnayake KM, Witek MA, Dathathreya K, Hupert ML, Soper SA. Label-free counting of affinity-enriched circulating tumor cells (CTCs) using a thermoplastic micro-Coulter counter (μCC). Analyst 2020; 145:1677-1686. [PMID: 31867587 PMCID: PMC7350181 DOI: 10.1039/c9an01802f] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Coulter counters are used for counting particles and biological cells. Most Coulter counters are designed to analyze a sample without the ability to pre-process the sample prior to counting. For the analysis of rare cells, such as circulating tumor cells (CTCs), it is not uncommon to require enrichment before counting due to the modest throughput of μCCs and the high abundance of interfering cells, such as blood cells. We report a microfluidic-based Coulter Counter (μCC) fabricated using simple, low-cost techniques for counting rare cells that can be interfaced to sample pre- and/or post-processing units. In the current work, a microfluidic device for the affinity-based enrichment of CTCs from whole blood into a relatively small volume of ∼10 μL was interfaced to the μCC to allow for exhaustive counting of single CTCs following release of the CTCs from the enrichment chip. When integrated to the CTC affinity enrichment chip, the μCC could count the CTCs without loss and the cells could be collected for downstream molecular profiling or culturing if required. The μCC sensor counting efficiency was >93% and inter-chip variability was ∼1%.
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Affiliation(s)
- Cong Kong
- Department of Chemistry, The University of Kansas, Lawrence, KS 66047, USA and Center of BioModular Multiscale Systems for Precision Medicine, The University of Kansas, Lawrence, KS 66047, USA and Key Laboratory of East China Sea Fishery Resources Exploitation, Ministry of Agriculture and Rural Affairs, East China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Shanghai 200090, China
| | - Mengjia Hu
- BioFluidica, Inc., Lawrence, KS 66047, USA.
| | - Kumuditha M Weerakoon-Ratnayake
- Department of Chemistry, The University of Kansas, Lawrence, KS 66047, USA and Center of BioModular Multiscale Systems for Precision Medicine, The University of Kansas, Lawrence, KS 66047, USA
| | - Malgorzata A Witek
- Department of Chemistry, The University of Kansas, Lawrence, KS 66047, USA and Center of BioModular Multiscale Systems for Precision Medicine, The University of Kansas, Lawrence, KS 66047, USA
| | - Kavya Dathathreya
- Department of Chemistry, The University of Kansas, Lawrence, KS 66047, USA and Center of BioModular Multiscale Systems for Precision Medicine, The University of Kansas, Lawrence, KS 66047, USA
| | | | - Steven A Soper
- Department of Chemistry, The University of Kansas, Lawrence, KS 66047, USA and Center of BioModular Multiscale Systems for Precision Medicine, The University of Kansas, Lawrence, KS 66047, USA and BioFluidica, Inc., Lawrence, KS 66047, USA. and BioEngineering Program, The University of Kansas, Lawrence, KS 66047, USA and Department of Mechanical Engineering, The University of Kansas, Lawrence, KS 66047.
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17
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Real-time particle-by-particle detection of erythrocyte-camouflaged microsensor with extended circulation time in the bloodstream. Proc Natl Acad Sci U S A 2020; 117:3509-3517. [PMID: 32019879 DOI: 10.1073/pnas.1914913117] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Personalized medicine offers great potential benefits for disease management but requires continuous monitoring of drugs and drug targets. For instance, the therapeutic window for lithium therapy of bipolar disorder is very narrow, and more frequent monitoring of sodium levels could avoid toxicity. In this work, we developed and validated a platform for long-term, continuous monitoring of systemic analyte concentrations in vivo. First, we developed sodium microsensors that circulate directly in the bloodstream. We used "red blood cell mimicry" to achieve long sensor circulation times of up to 2 wk, while being stable, reversible, and sensitive to sodium over physiologically relevant concentration ranges. Second, we developed an external optical reader to detect and quantify the fluorescence activity of the sensors directly in circulation without having to draw blood samples and correlate the measurement with a phantom calibration curve to measure in vivo sodium. The reader design is inherently scalable to larger limbs, species, and potentially even humans. In combination, this platform represents a paradigm for in vivo drug monitoring that we anticipate will have many applications in the future.
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Steenbergen W, Zharov VP. Towards Reaching the Total Blood Volume by in vivo Flow Cytometry and Theranostics. Cytometry A 2019; 95:1223-1225. [PMID: 31670875 PMCID: PMC6972999 DOI: 10.1002/cyto.a.23916] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2019] [Revised: 09/28/2019] [Accepted: 10/01/2019] [Indexed: 01/28/2023]
Affiliation(s)
- Wiendelt Steenbergen
- Biomedical Photonic Imaging, Techmed Center, Faculty of Science and Technology, University of Twente, 7500 NB, Enschede, The Netherlands
| | - Vladimir P Zharov
- Arkansas Nanomedicine Center, University of Arkansas for Medical Sciences, Little Rock, Arkansas, 72205.,Laboratory of Biomedical Photoacoustics, Saratov State University, Saratov, 410012, Russia
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19
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Patil R, Tan X, Bartosik P, Detappe A, Runnels JM, Ghobrial I, Lin CP, Niedre M. Fluorescence monitoring of rare circulating tumor cell and cluster dissemination in a multiple myeloma xenograft model in vivo. JOURNAL OF BIOMEDICAL OPTICS 2019; 24:1-11. [PMID: 31456386 PMCID: PMC6983486 DOI: 10.1117/1.jbo.24.8.085004] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Accepted: 08/05/2019] [Indexed: 05/20/2023]
Abstract
Circulating tumor cells (CTCs) are of great interest in cancer research because of their crucial role in hematogenous metastasis. We recently developed “diffuse in vivo flow cytometry” (DiFC), a preclinical research tool for enumerating extremely rare fluorescently labeled CTCs directly in vivo. In this work, we developed a green fluorescent protein (GFP)-compatible version of DiFC and used it to noninvasively monitor tumor cell numbers in circulation in a multiple myeloma (MM) disseminated xenograft mouse model. We show that DiFC allowed enumeration of CTCs in individual mice overtime during MM growth, with sensitivity below 1 CTC mL − 1 of peripheral blood. DiFC also revealed the presence of CTC clusters (CTCCs) in circulation to our knowledge for the first time in this model and allowed us to calculate CTCC size, frequency, and kinetics of shedding. We anticipate that the unique capabilities of DiFC will have many uses in preclinical study of metastasis, in particular, with a large number of GFP-expressing xenograft and transgenic mouse models.
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Affiliation(s)
- Roshani Patil
- Northeastern University, Department of Bioengineering, Boston, Massachusetts, United States
| | - Xuefei Tan
- Northeastern University, Department of Electrical and Computer Engineering, Boston, Massachusetts, United States
| | - Peter Bartosik
- Northeastern University, Department of Bioengineering, Boston, Massachusetts, United States
| | - Alexandre Detappe
- Dana Farber Cancer Institute, Harvard Medical School, Department of Medical Oncology, Boston, Massachusetts, United States
| | - Judith M. Runnels
- Massachusetts General Hospital and Harvard Medical School, Center for Systems Biology and Wellman Center for Photomedicine, Boston, Massachusetts, United States
| | - Irene Ghobrial
- Dana Farber Cancer Institute, Harvard Medical School, Department of Medical Oncology, Boston, Massachusetts, United States
| | - Charles P. Lin
- Massachusetts General Hospital and Harvard Medical School, Center for Systems Biology and Wellman Center for Photomedicine, Boston, Massachusetts, United States
| | - Mark Niedre
- Northeastern University, Department of Bioengineering, Boston, Massachusetts, United States
- Northeastern University, Department of Electrical and Computer Engineering, Boston, Massachusetts, United States
- Address all correspondence to Mark Niedre, E-mail:
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20
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Suo Y, Gu Z, Wei X. Advances of In Vivo Flow Cytometry on Cancer Studies. Cytometry A 2019; 97:15-23. [DOI: 10.1002/cyto.a.23851] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2019] [Revised: 05/27/2019] [Accepted: 06/14/2019] [Indexed: 12/24/2022]
Affiliation(s)
- Yuanzhen Suo
- Biomedical Pioneering Innovation CenterPeking University Beijing China
- School of Life SciencesPeking University Beijing China
| | - Zhenqin Gu
- Department of Urology, Xinhua HospitalShanghai Jiao Tong University School of Medicine Shanghai China
| | - Xunbin Wei
- Med‐X Research Institute and School of Biomedical EngineeringShanghai Jiao Tong University Shanghai China
- School of PhysicsFoshan University Foshan 52800 China
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21
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Abstract
Circulating tumor cells (CTCs) are of great interest in cancer research, but methods for their enumeration remain far from optimal. We developed a new small animal research tool called “Diffuse in vivo Flow Cytometry” (DiFC) for detecting extremely rare fluorescently-labeled circulating cells directly in the bloodstream. The technique exploits near-infrared diffuse photons to detect and count cells flowing in large superficial arteries and veins without drawing blood samples. DiFC uses custom-designed, dual fiber optic probes that are placed in contact with the skin surface approximately above a major vascular bundle. In combination with a novel signal processing algorithm, DiFC allows counting of individual cells moving in arterial or venous directions, as well as measurement of their speed and depth. We show that DiFC allows sampling of the entire circulating blood volume of a mouse in under 10 minutes, while maintaining a false alarm rate of 0.014 per minute. In practice, this means that DiFC allows reliable detection of circulating cells below 1 cell per mL. Hence, the unique capabilities of DiFC are highly suited to biological applications involving very rare cell types such as the study of hematogenous cancer metastasis.
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