1
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Delong LM, Witt CE, Pennell M, Ross AE. A microfluidic chip for sustained oxygen gradient formation in the intestine ex vivo. LAB ON A CHIP 2024; 24:1918-1929. [PMID: 38372633 PMCID: PMC10998727 DOI: 10.1039/d3lc00793f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/20/2024]
Abstract
The oxygen gradient across the intestine influences intestinal physiology and the microbial environment of the microbiome. The microbiome releases metabolites that communicate with enterochromaffin cells, neuronal cells, and resident immune cells to facilitate the bidirectional communication across the gut-brain axis. Measuring communication between various cell types within the intestine could provide essential information about key regulators of gut and brain health; however, the microbial environment of the intestine is heavily dependent on the physiological oxygen gradient that exists across the intestinal wall. Likewise, there exist a need for methods which enable real-time monitoring of intestinal signaling ex vivo yet this remains challenging due to the inability to adequately culture intestinal tissue ex vivo while also exposing the appropriate locations of the intestine for probe insertion and monitoring. Here, we designed and fabricated a 3D printed microfluidic device to maintain the oxygen gradient across precision cut murine intestinal slices with the capability to couple to external neurochemical recording techniques. The gradient is maintained from outlets below while allowing access to the slice from above for detection with fast scan cyclic voltammetry (FSCV) and carbon-fiber microelectrodes. A series of 11 outlet ports were designed to lay underneath the slice which were connected to channels to deliver oxygenated vs. deoxygenated media. Outlet ports were designed in an oval shape where deoxygenated media was delivered to the center of the slice and oxygenated media is delivered to the outer portion of the slice to mimic the location of oxygen across the intestine. An oxygen sensitive fluorescent dye, tris(2,2'-bipyridyl)dichlororuthenium(II), was used to characterize the tunability of the gradient. Viability of the tissue was confirmed by both fluorescence microscopy and FSCV. Additionally, we measured simultaneous serotonin and melatonin signaling with FSCV in the intestine for the first time. Overall, this chip provides a significant advance in our ability to culture intestinal slices ex vivo with the added benefit of direct access for measurements and imaging.
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Affiliation(s)
- Lauren M Delong
- Department of Chemistry, University of Cincinnati, 312 College Dr., 404 Crosley Tower, Cincinnati, OH 45221-0172, USA.
| | - Colby E Witt
- Department of Chemistry, University of Cincinnati, 312 College Dr., 404 Crosley Tower, Cincinnati, OH 45221-0172, USA.
| | - Madison Pennell
- Department of Chemistry, University of Cincinnati, 312 College Dr., 404 Crosley Tower, Cincinnati, OH 45221-0172, USA.
| | - Ashley E Ross
- Department of Chemistry, University of Cincinnati, 312 College Dr., 404 Crosley Tower, Cincinnati, OH 45221-0172, USA.
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2
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Brooke AK, Murrow DP, Caldwell KCN, Witt CE, Ross AE. Measuring neuron-regulated immune cell physiology via the alpha-2 adrenergic receptor in an ex vivo murine spleen model. Cell Mol Life Sci 2023; 80:354. [PMID: 37945921 PMCID: PMC11071927 DOI: 10.1007/s00018-023-05012-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2023] [Revised: 09/27/2023] [Accepted: 10/23/2023] [Indexed: 11/12/2023]
Abstract
The communication between the nervous and immune systems plays a crucial role in regulating immune cell function and inflammatory responses. Sympathetic neurons, which innervate the spleen, have been implicated in modulating immune cell activity. The neurotransmitter norepinephrine (NE), released by sympathetic neurons, influences immune cell responses by binding to adrenergic receptors on their surface. The alpha-2 adrenergic receptor (α2AR), expressed predominantly on sympathetic neurons, has received attention due to its autoreceptor function and ability to modulate NE release. In this study, we used fast-scan cyclic voltammetry (FSCV) to provide the first subsecond measurements of NE released in the white pulp region of the spleen and validated it with yohimbine, a known antagonist of α2AR. For further application of FSCV in neuroimmunology, we investigated the extent to which subsecond NE from sympathetic neurons is important for immune cell physiology and cytokine production, focusing on tumor necrosis factor-alpha (TNF-α), interleukin-10 (IL-10), and interleukin-6 (IL-6). Our findings provide insights into the regulatory mechanisms underlying sympathetic-immune interactions and show the significance of using FSCV, a traditional neurochemistry technique, to study these neuroimmune mechanisms.
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Affiliation(s)
- Alexandra K Brooke
- Department of Chemistry, University of Cincinnati, 312 College Dr. 404 Crosley Tower, Cincinnati, OH, 45221-0172, USA
| | - Daniel P Murrow
- Department of Chemistry, University of Cincinnati, 312 College Dr. 404 Crosley Tower, Cincinnati, OH, 45221-0172, USA
| | - Kaejaren C N Caldwell
- Department of Chemistry, University of Cincinnati, 312 College Dr. 404 Crosley Tower, Cincinnati, OH, 45221-0172, USA
| | - Colby E Witt
- Department of Chemistry, University of Cincinnati, 312 College Dr. 404 Crosley Tower, Cincinnati, OH, 45221-0172, USA
| | - Ashley E Ross
- Department of Chemistry, University of Cincinnati, 312 College Dr. 404 Crosley Tower, Cincinnati, OH, 45221-0172, USA.
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3
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Ozulumba T, Montalbine AN, Ortiz-Cárdenas JE, Pompano RR. New tools for immunologists: models of lymph node function from cells to tissues. Front Immunol 2023; 14:1183286. [PMID: 37234163 PMCID: PMC10206051 DOI: 10.3389/fimmu.2023.1183286] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Accepted: 04/20/2023] [Indexed: 05/27/2023] Open
Abstract
The lymph node is a highly structured organ that mediates the body's adaptive immune response to antigens and other foreign particles. Central to its function is the distinct spatial assortment of lymphocytes and stromal cells, as well as chemokines that drive the signaling cascades which underpin immune responses. Investigations of lymph node biology were historically explored in vivo in animal models, using technologies that were breakthroughs in their time such as immunofluorescence with monoclonal antibodies, genetic reporters, in vivo two-photon imaging, and, more recently spatial biology techniques. However, new approaches are needed to enable tests of cell behavior and spatiotemporal dynamics under well controlled experimental perturbation, particularly for human immunity. This review presents a suite of technologies, comprising in vitro, ex vivo and in silico models, developed to study the lymph node or its components. We discuss the use of these tools to model cell behaviors in increasing order of complexity, from cell motility, to cell-cell interactions, to organ-level functions such as vaccination. Next, we identify current challenges regarding cell sourcing and culture, real time measurements of lymph node behavior in vivo and tool development for analysis and control of engineered cultures. Finally, we propose new research directions and offer our perspective on the future of this rapidly growing field. We anticipate that this review will be especially beneficial to immunologists looking to expand their toolkit for probing lymph node structure and function.
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Affiliation(s)
- Tochukwu Ozulumba
- Department of Chemistry, University of Virginia, Charlottesville, VA, United States
| | - Alyssa N. Montalbine
- Department of Chemistry, University of Virginia, Charlottesville, VA, United States
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University School of Medicine, Atlanta, GA, United States
| | - Jennifer E. Ortiz-Cárdenas
- Department of Chemistry, University of Virginia, Charlottesville, VA, United States
- Department of Bioengineering, Stanford University, Stanford, CA, United States
| | - Rebecca R. Pompano
- Department of Chemistry, University of Virginia, Charlottesville, VA, United States
- Department of Biomedical Engineering, University of Virginia, Charlottesville, VA, United States
- Carter Immunology Center and University of Virginia (UVA) Cancer Center, University of Virginia School of Medicine, Charlottesville, VA, United States
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4
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Walker NL, Dick JE. On the mechanism of the bipolar reference electrode. Analyst 2023; 148:2149-2158. [PMID: 37042122 PMCID: PMC10308696 DOI: 10.1039/d3an00107e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/25/2023]
Abstract
Commercial silver/silver chloride (Ag/AgCl) reference electrodes are some of the most commonly used reference electrodes, but they suffer from a number of issues due to their porous frits. Such issues include difficulty miniaturizing, silver and chloride ion leakage, charge screening effects at low ionic strength, frit drying if left unattended in air, and incompatibility with organic solvents. To solve these issues, we recently designed a reference electrode that is leakless in principle by replacing the porous frit with a sealed, conductive wire, where the ends of the wire are exposed to the reference electrode solution and the working electrode solution. We hypothesized that the reference electrode operated like a closed, bipolar electrochemical cell, and we termed the name bipolar reference electrode (BPRE). Here, we provide evidence that the BPRE can either act as a reference electrode by operating through an ion transfer mechanism via leakage through the imperfect seal, or it can act as a highly stable quasi-reference electrode through a bipolar electron transfer mechanism (BPQRE). Finally, we demonstrate the effectiveness of the BPRE in other types of common electrochemical studies, including chronoamperometry, linear sweep voltammetry, differential pulse voltammetry, and electrochemical impedance spectroscopy.
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Affiliation(s)
- Nicole L Walker
- Department of Chemistry, Purdue University, West Lafayette, IN 47907, USA.
| | - Jeffrey E Dick
- Department of Chemistry, Purdue University, West Lafayette, IN 47907, USA.
- Elmore Family School of Electrical and Computer Engineering, Purdue University, West Lafayette, IN 47907, USA
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5
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Control of lymph node activity by direct local innervation. Trends Neurosci 2022; 45:704-712. [PMID: 35820971 DOI: 10.1016/j.tins.2022.06.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2022] [Revised: 05/25/2022] [Accepted: 06/15/2022] [Indexed: 11/24/2022]
Abstract
The nervous system detects environmental and internal stimuli and relays this information to immune cells via neurotransmitters and neuropeptides. This is essential to respond appropriately to immunogenic threats and to support system homeostasis. Lymph nodes (LNs) act as sentinels where adaptive immune responses are generated. They are richly innervated by peripheral sympathetic and sensory nerves, which are responsible for the local secretion of neurotransmitters by sympathetic fibers, such as norepinephrine, and neuropeptides by sensory fibers, including calcitonin gene-related peptide (CGRP) and substance P. Additionally, time-of-day-dependent oscillations in nerve activity are associated with differential immune responses, suggesting a potential role for neuroimmune interactions in coordinating immunity in a circadian fashion. Here, we discuss how LN activity is controlled by local innervation.
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6
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Cryan MT, Li Y, Ross AE. Sustained delivery of focal ischemia coupled to real-time neurochemical sensing in brain slices. LAB ON A CHIP 2022; 22:2173-2184. [PMID: 35531656 PMCID: PMC9156565 DOI: 10.1039/d1lc00908g] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Local stimulation of tissue can occur naturally in events like immune-mediated inflammation and focal ischemic injuries in brain and is confined to specific regions within tissue, occurring on various timescales. Making chemical measurements at the exact site of stimulation with current technologies is difficult yet important for understanding tissue response. We have developed a microfluidic device capable of local stimulation of brain slices with minimal lateral spread over time and submillimeter, tunable spatial resolution. This device is compatible with electrochemical measurements to monitor signaling at the site of stimulation over time. The PDMS-based device is three layers and contains a culture well, channel layer, and exit port layer for the channels. Channels with exit ports straddling the stimulus channels and ports were specifically fabricated to focus the stimulus over time. We demonstrated that the device is compatible with fast-scan cyclic voltammetry (FSCV) recording of neurotransmitter release. Localized hypoxia in tissue was verified using Image-iT Green Hypoxia Reagent and coupling this device with FSCV enabled measurement of local dopamine changes at the site of focal ischemia for the first time. This work provides a significant advance in knowledge of local neurochemical fluctuations during sustained tissue injury. Overall, the unique capabilities of the device to deliver sustained localized stimulation combined with real-time sensing provide an innovative platform to answer significant biological questions about how tissues respond at the site of controlled, localized injury and chemical stimulation.
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Affiliation(s)
- Michael T Cryan
- University of Cincinnati, Department of Chemistry, 312 College Drive, 404 Crosley Tower, Cincinnati, OH 45221-0172, USA.
| | - Yuxin Li
- University of Cincinnati, Department of Chemistry, 312 College Drive, 404 Crosley Tower, Cincinnati, OH 45221-0172, USA.
| | - Ashley E Ross
- University of Cincinnati, Department of Chemistry, 312 College Drive, 404 Crosley Tower, Cincinnati, OH 45221-0172, USA.
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7
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Li Y, Keller AL, Cryan MT, Ross AE. Metal Nanoparticle Modified Carbon-Fiber Microelectrodes Enhance Adenosine Triphosphate Surface Interactions with Fast-Scan Cyclic Voltammetry. ACS MEASUREMENT SCIENCE AU 2022; 2:96-105. [PMID: 35479102 PMCID: PMC9026253 DOI: 10.1021/acsmeasuresciau.1c00026] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Revised: 09/21/2021] [Accepted: 09/22/2021] [Indexed: 05/08/2023]
Abstract
Adenosine triphosphate (ATP) is an important rapid signaling molecule involved in a host of pathologies in the body. Historically, ATP is difficult to directly detect electrochemically with fast-scan cyclic voltammetry (FSCV) due to limited interactions at bare carbon-fibers. Systematic investigations of how ATP interacts at electrode surfaces is necessary for developing more sensitive electrochemical detection methods. Here, we have developed gold nanoparticle (AuNP), and platinum nanoparticle (PtNP) modified carbon-fiber microelectrodes coupled to FSCV to measure the extent to which ATP interacts at metal nanoparticle-modified surfaces and to improve the sensitivity of direct electrochemical detection. AuNP and PtNPs were electrodeposited on the carbon-fiber surface by scanning from -1.2 to 1.5 V for 30 s in 0.5 mg/mL HAuCl4 or 0.5 mg/mLK2PtCl6. Overall, we demonstrate an average 4.1 ± 1.0-fold increase in oxidative ATP current at AuNP-modified and a 3.5 ± 0.3-fold increase at PtNP-modified electrodes. Metal nanoparticle-modified surfaces promoted improved electrocatalytic conversion of ATP oxidation products at the surface, facilitated enhanced adsorption strength and surface coverage, and significantly improved sensitivity. ATP was successfully detected within living murine lymph node tissue following exogenous application. Overall, this study demonstrates a detailed characterization of ATP oxidation at metal nanoparticle surfaces and a significantly improved method for direct electrochemical detection of ATP in tissue.
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8
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Keller AL, Quarin SM, Strobbia P, Ross AE. Platinum Nanoparticle Size and Density Impacts Purine Electrochemistry with Fast-Scan Cyclic Voltammetry. JOURNAL OF THE ELECTROCHEMICAL SOCIETY 2022; 169:046514. [PMID: 35497383 PMCID: PMC9053744 DOI: 10.1149/1945-7111/ac65bc] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
We demonstrate the density and shape of platinum nanoparticles (PtNP) on carbon-fiber microelectrodes with fast-scan cyclic voltammetry (FSCV) directly impacts detection of adenosine. Previously, we showed that metal nanoparticle-modified carbon significantly improves adenine-based purine detection; however, how the size and shape of the particles impact electrochemical detection was not investigated. Electrochemical investigations of how the surface topology and morphology impacts detection is necessary for designing ultrasensitive electrodes and for expanding fundamental knowledge of electrode-analyte interactions. To change the density and shape of the PtNP's on the surface, we varied the concentration of K2PtCl6 and electrodeposition time. We show that increasing the concentration of K2PtCl6 increases the density of PtNP's while increasing the electrodeposition time impacts both the density and size. These changes manipulate the adsorption behavior which impacts sensitivity. Based on these results, an optimal electrodeposition procedure was determined to be 1.0 mg/mL of K2PtCl6 deposited for 45 s and this results in an average increase in adenosine detection by 3.5 ±0.3-fold. Interestingly, increasing the size and density of PtNPs negatively impacts dopamine detection. Overall, this work provides fundamental insights into the differences between adenosine and dopamine interaction at electrode surfaces.
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9
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Hinkle L, Liu Y, Meng C, Chen Z, Mai J, Zhang L, Xu Y, Pan PY, Chen SH, Shen H. The Sympathetic Nervous System Modulates Cancer Vaccine Activity through Monocyte-Derived Cells. THE JOURNAL OF IMMUNOLOGY 2021; 207:3131-3140. [PMID: 34772699 DOI: 10.4049/jimmunol.2100719] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Accepted: 10/05/2021] [Indexed: 11/19/2022]
Abstract
The sympathetic nervous system (SNS) is an important regulator of immune cell function during homeostasis and states of inflammation. Recently, the SNS has been found to bolster tumor growth and impair the development of antitumor immunity. However, it is unclear whether the SNS can modulate APC function. Here, we investigated the effects of SNS signaling in murine monocyte-derived macrophages (moMФ) and dendritic cells (DCs) and further combined the nonspecific β-blocker propranolol with a peptide cancer vaccine for the treatment of melanoma in mice. We report that norepinephrine treatment dramatically altered moMФ cytokine production, whereas DCs were unresponsive to norepinephrine and critically lack β2-adrenergic receptor expression. In addition, we show that propranolol plus cancer vaccine enhanced peripheral DC maturation, increased the intratumor proportion of effector CD8+ T cells, and decreased the presence of intratumor PD-L1+ myeloid-derived suppressor cells. Furthermore, this combination dramatically reduced tumor growth compared with vaccination alone. Taken together, these results offer insights into the cell-specific manner by which the SNS regulates the APC immune compartment and provide strong support for the use of propranolol in combination with cancer vaccines to improve patient response rates and survival.
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Affiliation(s)
- Louis Hinkle
- Department of Nanomedicine, Houston Methodist Research Institute, Houston, TX.,Texas A&M Health Science Center, Bryan, TX
| | - Yongbin Liu
- Department of Nanomedicine, Houston Methodist Research Institute, Houston, TX
| | - Chaoyang Meng
- Department of Nanomedicine, Houston Methodist Research Institute, Houston, TX.,Xiangya Hospital of Central South University, Changsha, Hunan, China
| | - Zhe Chen
- Department of Nanomedicine, Houston Methodist Research Institute, Houston, TX.,Xiangya Hospital of Central South University, Changsha, Hunan, China
| | - Junhua Mai
- Department of Nanomedicine, Houston Methodist Research Institute, Houston, TX
| | - Licheng Zhang
- Center for Cancer Immunotherapy, Houston Methodist Research Institute, Houston, TX; and
| | - Yitian Xu
- Center for Cancer Immunotherapy, Houston Methodist Research Institute, Houston, TX; and
| | - Ping-Ying Pan
- Center for Cancer Immunotherapy, Houston Methodist Research Institute, Houston, TX; and.,Weill Cornell Medical College, New York, NY
| | - Shu-Hsia Chen
- Center for Cancer Immunotherapy, Houston Methodist Research Institute, Houston, TX; and.,Weill Cornell Medical College, New York, NY
| | - Haifa Shen
- Department of Nanomedicine, Houston Methodist Research Institute, Houston, TX; .,Weill Cornell Medical College, New York, NY
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10
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Walker NL, Dick JE. Leakless, Bipolar Reference Electrodes: Fabrication, Performance, and Miniaturization. Anal Chem 2021; 93:10065-10074. [PMID: 34263595 DOI: 10.1021/acs.analchem.1c00675] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Reference electrodes must maintain a well-defined potential for long periods of time to be useful. The silver/silver chloride (Ag/AgCl) reference electrode is arguably the most widely used reference electrode, but it leaks silver and chloride ions into the sample solution through the porous frit over time. Further, the porous frit makes miniaturization to the micro- and nanoscale challenging. Here, we present an alternative, where the traditional Ag/AgCl reference electrode porous frit is replaced by a conductive wire, preventing ion leakage and allowing miniaturization to the microscale. Charge balance is maintained through a closed bipolar electrochemical mechanism, where faradaic processes occur on each end of the sealed wire. Using the above design, we demonstrate the efficacy of the leakless, bipolar reference electrode (BPRE) and miniaturize it to the microscale (μ-leakless BPRE). Importantly, we demonstrate that leakless and μ-leakless BPREs behave the same as commercial reference electrodes during potentiometric measurements and leakless BPREs perform similarly during voltammetric measurements on ultramicroelectrodes. We demonstrate that the drift during voltammetry using a leakless BPRE on a macroelectrode is slightly more appreciable compared to the drift seen with a commercial reference electrode. We detail design principles for the use of leakless BPREs in nonaqueous solvents and in sealing other conductive materials (e.g., gold and carbon). Using mass spectrometry, we show that the maximum leakage of methylene blue is 0.36 fmol/s, at least 2 orders of magnitude smaller than that of commercial reference electrodes. Finally, we demonstrate the efficacy of using leakless BPREs in potentiometric glucose sensing.
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Affiliation(s)
- Nicole L Walker
- Department of Chemistry, The University of North Carolina at Chapel Hill, 27599 Chapel Hill, North Carolina, United States
| | - Jeffrey E Dick
- Department of Chemistry, The University of North Carolina at Chapel Hill, 27599 Chapel Hill, North Carolina, United States.,Lineberger Comprehensive Cancer Center, School of Medicine, The University of North Carolina at Chapel Hill, 27599 Chapel Hill, North Carolina, United States
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11
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Rafi H, Zestos AG. Review-Recent Advances in FSCV Detection of Neurochemicals via Waveform and Carbon Microelectrode Modification. JOURNAL OF THE ELECTROCHEMICAL SOCIETY 2021; 168:057520. [PMID: 34108735 PMCID: PMC8186302 DOI: 10.1149/1945-7111/ac0064] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
Fast scan cyclic voltammetry (FSCV) is an analytical technique that was first developed over 30 years ago. Since then, it has been extensively used to detect dopamine using carbon fiber microelectrodes (CFMEs). More recently, electrode modifications and waveform refinement have enabled the detection of a wider variety of neurochemicals including nucleosides such as adenosine and guanosine, neurotransmitter metabolites of dopamine, and neuropeptides such as enkephalin. These alterations have facilitated the selectivity of certain biomolecules over others to enhance the measurement of the analyte of interest while excluding interferants. In this review, we detail these modifications and how specializing CFME sensors allows neuro-analytical researchers to develop tools to understand the neurochemistry of the brain in disease states and provide groundwork for translational work in clinical settings.
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Affiliation(s)
- Harmain Rafi
- Department of Chemistry, American University, Washington, DC 20016, United States of America
- Center for Neuroscience and Behavior, American University, Washington, DC 20016, United States of America
| | - Alexander G. Zestos
- Department of Chemistry, American University, Washington, DC 20016, United States of America
- Center for Neuroscience and Behavior, American University, Washington, DC 20016, United States of America
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12
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Belanger M, Ball AG, Catterton MA, Kinman AW, Anbaei P, Groff BD, Melchor SJ, Lukens JR, Ross AE, Pompano RR. Acute Lymph Node Slices Are a Functional Model System to Study Immunity Ex Vivo. ACS Pharmacol Transl Sci 2021; 4:128-142. [PMID: 33615167 PMCID: PMC7887751 DOI: 10.1021/acsptsci.0c00143] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2020] [Indexed: 02/07/2023]
Abstract
The lymph node is a highly organized and dynamic structure that is critical for facilitating the intercellular interactions that constitute adaptive immunity. Most ex vivo studies of the lymph node begin by reducing it to a cell suspension, thus losing the spatial organization, or fixing it, thus losing the ability to make repeated measurements. Live murine lymph node tissue slices offer the potential to retain spatial complexity and dynamic accessibility, but their viability, level of immune activation, and retention of antigen-specific functions have not been validated. Here we systematically characterized live murine lymph node slices as a platform to study immunity. Live lymph node slices maintained the expected spatial organization and cell populations while reflecting the 3D spatial complexity of the organ. Slices collected under optimized conditions were comparable to cell suspensions in terms of both 24-h viability and inflammation. Slices responded to T cell receptor cross-linking with increased surface marker expression and cytokine secretion, in some cases more strongly than matched lymphocyte cultures. Furthermore, slices processed protein antigens, and slices from vaccinated animals responded to ex vivo challenge with antigen-specific cytokine secretion. In summary, lymph node slices provide a versatile platform to investigate immune functions in spatially organized tissue, enabling well-defined stimulation, time-course analysis, and parallel read-outs.
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Affiliation(s)
- Maura
C. Belanger
- Department
of Chemistry, University of Virginia College
of Arts and Sciences, Charlottesville, Virginia 22904, United States
- Carter
Immunology Center, University of Virginia, Charlottesville, Virginia 22904, United States
| | - Alexander G. Ball
- Carter
Immunology Center, University of Virginia, Charlottesville, Virginia 22904, United States
- Department
of Microbiology, Immunology and Cancer Biology, University of Virginia School of Medicine, Charlottesville, Virginia 22904, United States
| | - Megan A. Catterton
- Department
of Chemistry, University of Virginia College
of Arts and Sciences, Charlottesville, Virginia 22904, United States
| | - Andrew W.L. Kinman
- Department
of Chemistry, University of Virginia College
of Arts and Sciences, Charlottesville, Virginia 22904, United States
| | - Parastoo Anbaei
- Department
of Chemistry, University of Virginia College
of Arts and Sciences, Charlottesville, Virginia 22904, United States
| | - Benjamin D. Groff
- Department
of Chemistry, University of Virginia College
of Arts and Sciences, Charlottesville, Virginia 22904, United States
| | - Stephanie J. Melchor
- Carter
Immunology Center, University of Virginia, Charlottesville, Virginia 22904, United States
- Department
of Microbiology, Immunology and Cancer Biology, University of Virginia School of Medicine, Charlottesville, Virginia 22904, United States
| | - John R. Lukens
- Carter
Immunology Center, University of Virginia, Charlottesville, Virginia 22904, United States
- Department
of Neuroscience and Center for Brain Immunology and Glia (BIG), University of Virginia School of Medicine, Charlottesville, Virginia 22904, United States
| | - Ashley E. Ross
- Department
of Chemistry, University of Cincinnati, Cincinnati, Ohio 45220, United States
| | - Rebecca R. Pompano
- Department
of Chemistry, University of Virginia College
of Arts and Sciences, Charlottesville, Virginia 22904, United States
- Carter
Immunology Center, University of Virginia, Charlottesville, Virginia 22904, United States
- Department
of Biomedical Engineering, University of
Virginia School of Engineering and Applied Sciences, Charlottesville, Virginia 22904, United States
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13
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Stefanaki C, Mastorakos G, Chrousos GP. Gut Microbiome and Mental Stress-Related Disorders: The Interplay of Classic and Microbial Endocrinology. GUT MICROBIOME-RELATED DISEASES AND THERAPIES 2021. [DOI: 10.1007/978-3-030-59642-2_7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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14
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Goldstein DS. The possible association between COVID-19 and postural tachycardia syndrome. Heart Rhythm 2020; 18:508-509. [PMID: 33316414 PMCID: PMC7729277 DOI: 10.1016/j.hrthm.2020.12.007] [Citation(s) in RCA: 93] [Impact Index Per Article: 23.3] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Revised: 12/01/2020] [Accepted: 12/07/2020] [Indexed: 12/14/2022]
Affiliation(s)
- David S Goldstein
- Autonomic Medicine Section, Clinical Neurosciences Program, Division of Intramural Research, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland.
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