scholarly journals Spatially resolved microfluidic stimulation of lymphoid tissue ex vivo

The Analyst ◽  
2017 ◽  
Vol 142 (4) ◽  
pp. 649-659 ◽  
Author(s):  
Ashley E. Ross ◽  
Maura C. Belanger ◽  
Jacob F. Woodroof ◽  
Rebecca R. Pompano
Keyword(s):  
Lymph Node ◽  
Targeted Delivery ◽  
Lymphoid Tissue ◽  
Ex Vivo ◽  
Tissue Slices ◽  
Microfluidic Platform ◽  
Spatially Resolved ◽  
Local Stimulation ◽  
Stimulation Of

We present the first microfluidic platform for local stimulation of lymph node tissue slices and demonstrate targeted delivery of a model therapeutic.

Ex vivo development of functional human lymph node and bronchus-associated lymphoid tissue

Blood ◽  
2002 ◽  
Vol 99 (7) ◽  
pp. 2483-2489 ◽  
Author(s):  
Rabindra Tirouvanziam ◽  
Ibrahim Khazaal ◽  
Victoire N'Sondé ◽  
Marie-Alix Peyrat ◽  
Annick Lim ◽  
...  
Keyword(s):  
T Cells ◽  
Lymph Node ◽  
Mast Cells ◽  
Lymphoid Tissue ◽  
Ex Vivo ◽  
Severe Combined Immunodeficiency ◽  
Experimental Models ◽  
In Vivo Model ◽  
Functional Relations

We introduce a novel in vivo model of human mucosal immunity, based on the implantation of human fetal bronchial mucosa and autologous peribronchial lymph node (PLN) in the severe combined immunodeficiency (SCID) mouse. In the SCID host, human fetal bronchi implanted alone retain macrophages and mast cells but lose T cells. In contrast, fetal bronchi co-implanted with PLN contain, in addition to macrophages and mast cells, numerous T cells and B cells, often clustered in intramucosal bronchus-associated lymphoid tissue (BALT). Functionally, bronchus–PLN cografts are able to mount robust αβ and γδ T-cell–mediated immune responses to Pseudomonas aeruginosa and 3,4-epoxy-3-methyl-1-butyl-diphosphate challenges. No other autologous lymphoid organ (bone marrow, thymus, liver) allows for BALT development in co-implanted bronchi, which suggests special ontogenetic and functional relations between extramucosal PLN and intramucosal BALT. Overall, the bronchus–PLN cograft appears as a promising model for human bronchial immune development and function. Our study is the first to document long-term ex vivo maintenance of functional human lymph nodes as native appendices to mucosal tissue. Our results, therefore, suggest a simple strategy for developing similar experimental models of human immune function in other mucosae.

scholarly journals Spatially Resolved Measurement of Dynamic Glucose Uptake in Live Ex Vivo Tissues

2020 ◽  
Author(s):  
Austin F. Dunn ◽  
Megan A. Catterton ◽  
Drake D. Dixon ◽  
Rebecca R. Pompano
Keyword(s):  
Lymph Node ◽  
T Cell ◽  
Glucose Uptake ◽  
Ex Vivo ◽  
Cell Types ◽  
Tissue Level ◽  
Slice Culture ◽  
Spatially Resolved ◽  
Glucose Analogue

ABSTRACTHighly proliferative cells depend heavily on glycolysis as a source of energy and biological precursor molecules, and glucose uptake is a useful readout of this aspect of metabolic activity. Glucose uptake is commonly quantified by using flow cytometry for cell cultures and positron emission tomography for organs in vivo. However, methods to detect spatiotemporally resolved glucose uptake in intact tissues are far more limited, particularly those that can quantify changes in uptake over time in specific tissue regions and cell types. Using lymph node metabolism as a case study, we developed a novel assay of dynamic and spatially resolved glucose uptake in living tissue by combining ex vivo tissue slice culture with a fluorescent glucose analogue. Live slices of murine lymph node were treated with the glucose analogue 2-[N-(7-nitrobenz-2-oxa-1,3-dia-xol-4-yl)amino]-2-deoxyglucose (2-NBDG). Incubation parameters were optimized to differentiate glucose uptake in activated versus naïve lymphocytes. Regional glucose uptake could be imaged at both the tissue level, by widefield microscopy, and at the cellular level, by confocal microscopy. Furthermore, the assay was readily multiplexed with live immunofluorescence labelling to generate maps of 2-NBDG uptake across tissue regions, revealing highest uptake in T cell-dense regions. The signal was predominantly intracellular and localized to lymphocytes rather than stromal cells. Finally, we demonstrated that the assay was repeatable in the same slices, and imaged the dynamic distribution of glucose uptake in response to ex vivo T cell stimulation for the first time. We anticipate that this assay will serve as a broadly applicable, user-friendly platform to quantify dynamic metabolic activities in complex tissue microenvironments.

scholarly journals Acute lymph node slices are a functional model system to study immunity ex vivo

2019 ◽  
Author(s):  
Maura C. Belanger ◽  
Alexander G. Ball ◽  
Megan A. Catterton ◽  
Andrew W.L. Kinman ◽  
Parastoo Anbaei ◽  
...  
Keyword(s):  
Lymph Node ◽  
Time Course ◽  
Spatial Organization ◽  
Ex Vivo ◽  
Functional Model ◽  
Repeated Measurements ◽  
Cytokine Secretion ◽  
Immune Functions ◽  
Tissue Slices ◽  
Spatial Complexity

AbstractThe 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-hr 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.

scholarly journals User-defined local stimulation of live tissue through a movable microfluidic port

Lab on a Chip ◽  
2018 ◽  
Vol 18 (14) ◽  
pp. 2003-2012 ◽  
Author(s):  
Megan A. Catterton ◽  
Austin F. Dunn ◽  
Rebecca R. Pompano
Keyword(s):  
Microfluidic Device ◽  
Living Tissue ◽  
Tissue Slices ◽  
Two Phase ◽  
Live Tissue ◽  
Two Component ◽  
Local Stimulation ◽  
Stimulation Of

A two-component, two-phase microfluidic device provides a movable port for user-selectable local stimulation of living tissue slices.

Early Platelet-Collagen Interactions in Whole Blood and Their Modifications by Aspirin and Dipyridamole Evaluated by a New Method (Basic Wave)

1985 ◽  
Vol 54 (04) ◽  
pp. 799-803 ◽  
Author(s):  
José Luís Pérez-Requejo ◽  
Justo Aznar ◽  
M Teresa Santos ◽  
Juana Vallés
Keyword(s):  
Whole Blood ◽  
Ex Vivo ◽  
Platelet Rich Plasma ◽  
White Blood Cells ◽  
Reversible Aggregation ◽  
Inhibitory Compounds ◽  
Rapid Generation ◽  
Stimulation Of ◽  
Collagen Stimulation

SummaryIt is shown that the supernatant of unstirred whole blood at 37° C, stimulated by 1 μg/ml of collagen for 10 sec, produces a rapid generation of pro and antiaggregatory compounds with a final proaggregatory activity which can be detected for more than 60 min on a platelet rich plasma (PRP) by turbidometric aggregometry. A reversible aggregation wave that we have called BASIC wave (for Blood Aggregation Stimulatory and Inhibitory Compounds) is recorded. The collagen stimulation of unstirred PRP produces a similar but smaller BASIC wave. BASIC’s intensity increases if erythrocytes are added to PRP but decreases if white blood cells are added instead. Aspirin abolishes “ex vivo” the ability of whole blood and PRP to generate BASIC waves and dipyridamole “in vitro” significantly reduces BASIC’s intensity in whole blood in every tested sample, but shows little effect in PRP.

XMODULATION IN MICEAND MEN: IL-10 PRODUCING CELLS INBLOOD AND LYMPHOID TISSUE

2008 ◽  
Vol 31 (4) ◽  
pp. 3
Author(s):  
L Barrett ◽  
M Grant ◽  
R Liwski ◽  
K West
Keyword(s):  
Immune System ◽  
Peripheral Blood ◽  
Lymphoid Tissue ◽  
Mononuclear Cells ◽  
Ex Vivo ◽  
White Blood Cells ◽  
Interleukin 10 ◽  
Healthy Individuals ◽  
Human Immune System ◽  
Healthy Humans

Background: The human immune system provides remarkable protection from a plethora of pathogens, but can cause damage when activated for a prolonged time (as inpersistent infections) or against self (autoimmunity). Therefore, mechanisms of immune system downregulation and control are imperative. There is little data on how the immune system is controlled in healthy individuals. We recently described a novel population of white blood cells that constitutively produce the immunomodulatory cytokine interleukin-10 (IL-10). Our objective was to further delineate the distribution of these cells in human and mouse models, as well as potential triggers for interleukin-10 production in vitro. Methods: Human and animal protocols were reviewed and approved by the institutional ethics board and animal care facilities, and informed consent was obtained from all human donors. The ex vivo percentage of peripheral blood CD36^+IL-10^+ mononuclear cells was assessed by intracellular flow cytometry in 10 healthy individuals. IL-10 production after exposure to twoCD36 ligands, thrombospondin and oxidized low density lipoprotein (oxLDL) was measured at 8 hours. Peripheral blood mononuclear cells and splenocytes from BL/6 (n=5) and Balb/c (n=1) micewere assessed for CD36^+IL-10^+ cells ex vivo as well. Results: The percentage of CD36^+IL-10^+ cells in peripheral blood fromhealthy individuals ranges between 0.1% and 0.9%. The percentage was similar in mouse peripheral blood, with a range of 0.4%-1.1%. These cells were also found in mouse spleen at a higher frequency than peripherally (1.1-1.5%). Human CD36^+IL-10^+ cells have more IL-10 when exposed to thrombospondin, oxLDL. Conclusions: Our novel population of IL-10 producing cells is found not only in healthy humans, but also in lymphoid tissue and blood from pathogen free mice. This highlights the evolutionary conservation of the cell across species, and suggests an important homeostatic function. The physiologic ligands for CD36 are ubiquitous in circulation, and ourin vitro data suggests a link between CD36 ligation and IL-10 production. IL-10 is a known immune system modulator, and its production by these cells may help maintain homeostaticcontrol of the immune system.

Development and Evaluation of Particulate Microcarriers of Adapalene as a Topical Delivery System

2019 ◽  
Vol 9 (3) ◽  
pp. 222-233
Author(s):  
Divya D. Jain ◽  
Namita D. Desai
Keyword(s):  
Patient Compliance ◽  
Targeted Delivery ◽  
Ex Vivo ◽  
Acne Vulgaris ◽  
Drug Loading ◽  
Topical Therapy ◽  
Skin Irritation ◽  
Topical Delivery ◽  
Diffusion Method ◽  
Topical Gel

Background: Adapalene is a promising third generation retinoid used in the topical treatment of acne vulgaris. However, the major drawback associated with conventional topical therapy of Adapalene is the ‘retinoid reaction’ which is dose-dependent and characterized by erythema, scaling and burning sensation at the application sites. Microparticulate drug delivery can play a major role in reducing side effects and providing better patient compliance due to targeted delivery. Methods: Adapalene microparticles were prepared using quasi emulsion solvent diffusion method. The effects of formulation variables including polymer ratios, amounts of emulsifier, drug loading and process variables such as stirring time and speed on the physical characteristics of microparticles were investigated. The developed microparticles were characterized by DSC and SEM. Adapalene microparticles were incorporated into Carbopol 971 NF gel for ease of topical delivery. Results: Adapalene microparticulate topical gel showed sustained drug release over 8 hours in in vitro studies. The amount of drug retained in the rat skin during ex vivo studies was higher in the microparticulate topical gel (227.43 ± 0.83 µg/cm2) as compared to the marketed formulation (81.4 ± 1.11 µg/cm2) after 8 hours indicating localized and sustained drug action that can be useful in treating acne vulgaris. The safety of optimized Adapalene gel determined by skin irritation studies performed on Sprague Dawley rats showed no irritation potential. Conclusion: Microparticles can provide promising carrier systems to deliver Adapalene, improving patient compliance due to enhanced skin deposition, localized and sustained action with reduced associated irritant effects.

Sign in / Sign up

Export Citation Format

Share Document