The evaluation of lymph node cell proliferation response by liposomes loaded with major histocompatibility complex class II binding aquaporin 4 antigen peptide

2020 ◽  
Vol 85 (3) ◽  
pp. 537-544
Author(s):  
Yo Muraki ◽  
Yutaka Nishimoto ◽  
Midori Yamasaki ◽  
Shuuichi Miyakawa ◽  
Shuji Sato
Keyword(s):  
Cell Proliferation ◽  
Dendritic Cells ◽  
Lymph Node ◽  
Imaging System ◽  
Ex Vivo ◽  
Aquaporin 4 ◽  
Antigen Peptide ◽  
New Strategy ◽  
Proliferation Response

ABSTRACT Autoimmune responses to aquaporin 4 (AQP4) cause neuromyelitis optica (NMO); thus, specific immunotolerance to this self-antigen could represent a new NMO treatment. We generated the liposome-encapsulated AQP4 peptide 201-220 (p201-220) to induce immunotolerance. Liposomes were generated using phosphatidylserine and the polyglycidol species PG8MG. The in vivo tissue distribution of the liposomes was tested using an ex vivo imaging system. To confirm the antigen presentation capacity of PG8MG liposomes, dendritic cells were treated with PG8MG liposome-encapsulated AQP4 p201-220 (AQP4-PG8MG liposomes). Immunotolerance induction by AQP4-PG8MG liposomes was evaluated using the ex vivo cell proliferation of lymph node cells isolated from AQP4 p201-220-immunized AQP4-deficient mice. Fluorescent dye-labeled PG8MG liposomes were distributed to the lymph nodes. AQP4 p201-220 was presented on dendritic cells. AQP4-PG8MG liposomes were tended to suppress immune responses to AQP4 p201-220. Thus, the encapsulation of AQP4 peptides in PG8MG liposomes represents a new strategy for suppressing autoimmune responses to AQP4.

scholarly journals Performance of a novel protease-activated fluorescent imaging system for intraoperative detection of residual breast cancer during breast conserving surgery

2021 ◽  
Vol 187 (1) ◽  
pp. 145-153
Author(s):  
Conor R. Lanahan ◽  
Bridget N. Kelly ◽  
Michele A. Gadd ◽  
Michelle C. Specht ◽  
Carson L. Brown ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Real Time ◽  
Imaging System ◽  
Ex Vivo ◽  
Menopausal Status ◽  
Fluorescent Imaging ◽  
Cancer Subtypes ◽  
Surgical Workflow ◽  
Tumor Types

Abstract Purpose Safe breast cancer lumpectomies require microscopically clear margins. Real-time margin assessment options are limited, and 20–40% of lumpectomies have positive margins requiring re-excision. The LUM Imaging System previously showed excellent sensitivity and specificity for tumor detection during lumpectomy surgery. We explored its impact on surgical workflow and performance across patient and tumor types. Methods We performed IRB-approved, prospective, non-randomized studies in breast cancer lumpectomy procedures. The LUM Imaging System uses LUM015, a protease-activated fluorescent imaging agent that identifies residual tumor in the surgical cavity walls. Fluorescent cavity images were collected in real-time and analyzed using system software. Results Cavity and specimen images were obtained in 55 patients injected with LUM015 at 0.5 or 1.0 mg/kg and in 5 patients who did not receive LUM015. All tumor types were distinguished from normal tissue, with mean tumor:normal (T:N) signal ratios of 3.81–5.69. T:N ratios were 4.45 in non-dense and 4.00 in dense breasts (p = 0.59) and 3.52 in premenopausal and 4.59 in postmenopausal women (p = 0.19). Histopathology and tumor receptor testing were not affected by LUM015. Falsely positive readings were more likely when tumor was present < 2 mm from the adjacent specimen margin. LUM015 signal was stable in vivo at least 6.5 h post injection, and ex vivo at least 4 h post excision. Conclusions Intraoperative use of the LUM Imaging System detected all breast cancer subtypes with robust performance independent of menopausal status and breast density. There was no significant impact on histopathology or receptor evaluation.

scholarly journals A Tumbling Magnetic Microrobot System for Biomedical Applications

Micromachines ◽  
2020 ◽  
Vol 11 (9) ◽  
pp. 861
Author(s):  
Elizabeth E. Niedert ◽  
Chenghao Bi ◽  
Georges Adam ◽  
Elly Lambert ◽  
Luis Solorio ◽  
...  
Keyword(s):  
Ultrasound Imaging ◽  
Biomedical Applications ◽  
Imaging System ◽  
Ex Vivo ◽  
Negative Control ◽  
Circular Path ◽  
Rotational Axis ◽  
Significant Difference

A microrobot system comprising an untethered tumbling magnetic microrobot, a two-degree-of-freedom rotating permanent magnet, and an ultrasound imaging system has been developed for in vitro and in vivo biomedical applications. The microrobot tumbles end-over-end in a net forward motion due to applied magnetic torque from the rotating magnet. By turning the rotational axis of the magnet, two-dimensional directional control is possible and the microrobot was steered along various trajectories, including a circular path and P-shaped path. The microrobot is capable of moving over the unstructured terrain within a murine colon in in vitro, in situ, and in vivo conditions, as well as a porcine colon in ex vivo conditions. High-frequency ultrasound imaging allows for real-time determination of the microrobot’s position while it is optically occluded by animal tissue. When coated with a fluorescein payload, the microrobot was shown to release the majority of the payload over a 1-h time period in phosphate-buffered saline. Cytotoxicity tests demonstrated that the microrobot’s constituent materials, SU-8 and polydimethylsiloxane (PDMS), did not show a statistically significant difference in toxicity to murine fibroblasts from the negative control, even when the materials were doped with magnetic neodymium microparticles. The microrobot system’s capabilities make it promising for targeted drug delivery and other in vivo biomedical applications.

scholarly journals Mesenchymal stem cells accelerated growth and metastasis of neuroblastoma and preferentially homed towards both primary and metastatic loci in orthotopic neuroblastoma model

BMC Cancer ◽  
2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Jiao-Le Yu ◽  
Shing Chan ◽  
Marcus Kwong-Lam Fung ◽  
Godfrey Chi-Fung Chan
Keyword(s):  
Stem Cells ◽  
Mesenchymal Stem Cells ◽  
Primary Tumor ◽  
Imaging System ◽  
Ex Vivo ◽  
Tumor Formation ◽  
Human Neuroblastoma Cell ◽  
Fluorescence Signal ◽  
Human Neuroblastoma

Abstract Background Majority of neuroblastoma patients develop metastatic disease at diagnosis and their prognosis is poor with current therapeutic approach. Major challenges are how to tackle the mechanisms responsible for tumorigenesis and metastasis. Human mesenchymal stem cells (hMSCs) may be actively involved in the constitution of cancer microenvironment. Methods An orthotopic neuroblastoma murine model was utilized to mimic the clinical scenario. Human neuroblastoma cell line SK-N-LP was transfected with luciferase gene, which were inoculated with/without hMSCs into the adrenal area of SCID-beige mice. The growth and metastasis of neuroblastoma was observed by using Xenogen IVIS 100 in vivo imaging and evaluating gross tumors ex vivo. The homing of hMSCs towards tumor was analyzed by tracing fluorescence signal tagged on hMSCs using CRI Maestro™ imaging system. Results hMSCs mixed with neuroblastoma cells significantly accelerated tumor growth and apparently enhanced metastasis of neuroblastoma in vivo. hMSCs could be recruited by primary tumor and also become part of the tumor microenvironment in the metastatic lesion. The metastatic potential was consistently reduced in lung and tumor when hMSCs were pre-treated with stromal cell derived factor-1 (SDF-1) blocker, AMD3100, suggesting that the SDF-1/CXCR4 axis was one of the prime movers in the metastatic process. Conclusions hMSCs accelerated and facilitated tumor formation, growth and metastasis. Furthermore, the homing propensity of hMSCs towards both primary tumor and metastatic loci can also provide new therapeutic insights in utilizing bio-engineered hMSCs as vehicles for targeted anti-cancer therapy.

A novel mouse model based on intersectional genetics enables unambiguous in vivo discrimination between plasmacytoid and other dendritic cells and their comparative characterization

2022 ◽  
Author(s):  
Michael Valente ◽  
Nils Collinet ◽  
Thien-Phong Vu Manh ◽  
Karima Naciri ◽  
Gilles Bessou ◽  
...  
Keyword(s):  
Dendritic Cells ◽  
Steady State ◽  
Mouse Model ◽  
Single Cell ◽  
Ex Vivo ◽  
High Specificity ◽  
Type I ◽  
Specific Expression ◽  
Physiological Functions

Plasmacytoid dendritic cells (pDC) were identified about 20 years ago, based on their unique ability to rapidly produce copious amounts of all subsets of type I and type III interferon (IFN-I/III) upon virus sensing, while being refractory to infection. Yet, the identity and physiological functions of pDC are still a matter of debate, in a large part due to their lack of specific expression of any single cell surface marker or gene that would allow to track them in tissues and to target them in vivo with high specificity and penetrance. Indeed, recent studies showed that previous methods that were used to identify or deplete pDC also targeted other cell types, including pDC-like cells and transitional DC (tDC) that were proposed to be responsible for all the antigen presentation ability previously attributed to steady state pDC. Hence, improving our understanding of the nature and in vivo choreography of pDC physiological functions requires the development of novel tools to unambiguously identify and track these cells, including in comparison to pDC-like cells and tDC. Here, we report successful generation of a pDC-reporter mouse model, by using an intersectional genetic strategy based on the unique co-expression of Siglech and Pacsin1 in pDC. This pDC-Tomato mouse strain allows specific ex vivo and in situ detection of pDC. Breeding them with Zbtb46GFP mice allowed side-by-side purification and transcriptional profiling by single cell RNA sequencing of bona fide pDC, pDC-like cells and tDC, in comparison to type 1 and 2 conventional DC (cDC1 and cDC2), both at steady state and during a viral infection, revealing diverging activation patterns of pDC-like cells and tDC. Finally, by breeding pDC-Tomato mice with Ifnb1EYFP mice, we determined the choreography of pDC recruitment to the micro-anatomical sites of viral replication in the spleen, with initially similar but later divergent behaviors of the pDC that engaged or not into IFN-I production. Our novel pDC-Tomato mouse model, and newly identified gene modules specific to combinations of DC types and activations states, will constitute valuable resources for a deeper understanding of the functional division of labor between DC types and its molecular regulation at homeostasis and during viral infections.

Antithymocyte Globulin Induces Ex Vivo and In Vivo Depletion of Myeloid and Plasmacytoid Dendritic Cells

2005 ◽  
Vol 79 (3) ◽  
pp. 369-371 ◽  
Author(s):  
Lubin Fang ◽  
Boris Fehse ◽  
Melanie Engel ◽  
Axel Zander ◽  
Nicolaus Kr??ger
Keyword(s):  
Dendritic Cells ◽  
Antithymocyte Globulin ◽  
Ex Vivo ◽  
Plasmacytoid Dendritic Cells

scholarly journals In Vivo Role of Dendritic Cells in a Murine Model of Pulmonary Cryptococcosis

2006 ◽  
Vol 74 (7) ◽  
pp. 3817-3824 ◽  
Author(s):  
Karen L. Wozniak ◽  
Jatin M. Vyas ◽  
Stuart M. Levitz
Keyword(s):  
T Cells ◽  
Dendritic Cells ◽  
T Cell Activation ◽  
Cell Activation ◽  
Ex Vivo ◽  
Interleukin 2 ◽  
Mouse Lung

ABSTRACT Dendritic cells (DC) have been shown to phagocytose and kill Cryptococcus neoformans in vitro and are believed to be important for inducing protective immunity against this organism. Exposure to C. neoformans occurs mainly by inhalation, and in this study we examined the in vivo interactions of C. neoformans with DC in the lung. Fluorescently labeled live C. neoformans and heat-killed C. neoformans were administered intranasally to C57BL/6 mice. At specific times postinoculation, mice were sacrificed, and lungs were removed. Single-cell suspensions of lung cells were prepared, stained, and analyzed by microscopy and flow cytometry. Within 2 h postinoculation, fluorescently labeled C. neoformans had been internalized by DC, macrophages, and neutrophils in the mouse lung. Additionally, lung DC from mice infected for 7 days showed increased expression of the maturation markers CD80, CD86, and major histocompatibility complex class II. Finally, ex vivo incubation of lung DC from infected mice with Cryptococcus-specific T cells resulted in increased interleukin-2 production compared to the production by DC from naïve mice, suggesting that there was antigen-specific T-cell activation. This study demonstrated that DC in the lung are capable of phagocytosing Cryptococcus in vivo and presenting antigen to C. neoformans-specific T cells ex vivo, suggesting that these cells have roles in innate and adaptive pulmonary defenses against cryptococcosis.

scholarly journals Between biology and medicine: perspectives on the use of dendritic cells in anticancer therapy

2017 ◽  
Vol 71 (0) ◽  
pp. 0-0
Author(s):  
Agnieszka Szczygieł ◽  
Elżbieta Pajtasz-Piasecka
Keyword(s):  
Dendritic Cells ◽  
Ex Vivo ◽  
Anticancer Therapy ◽  
Point Of View ◽  
Proper Function ◽  
Innate And Adaptive Immunity ◽  
Factors Affecting ◽  
Antigen Presenting

Dendritic cells (DCs), as a link between innate and adaptive immunity, play a pivotal role in maintaining homeostasis of the immune system. The DC population is characterized by heterogeneity; it consists of many subpopulations which, despite their phenotypic and localization differences, play an essential function – they are professional antigen presenting cells. Due to their role, DCs can be utilized in a new cancer treatment strategy. Their main purpose is to generate an anticancer response leading to the elimination of cancer cells. The tumor microenvironment, abundant in immunosuppressive factors (e.g. IL-10, TGF-β, Arg1, IDO), impairs the proper function of DCs. For this reason, various strategies are necessary for ex vivo preparation of DC-based vaccines and for the support of in vivo DCs to fight against tumors. DC-based vaccines are combined with other forms of immunotherapy (e.g. blockade of immune checkpoint molecules, e.g. PD-1 or CTLA-4) or conventional types of therapies (e.g. chemotherapy). Despite the enormous progress that has been made in anticancer therapy in the past two decades, there are still many unresolved issues regarding the effectiveness of the DCs usage. In this paper we described, in both a mouse and a human subject, a series of DC subpopulations, differentiating in normal conditions or under the influence of cancer microenvironment. We listed factors affecting the quality of the in vivo and ex vivo generations of antitumoral responses, significant from a therapeutic point of view. Moreover, the most important strategies for the use of DCs in anticancer therapies, as well as further developments on this field, have been discussed.

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