scholarly journals Intravital Imaging Allows Organ-Specific Insights Into Immune Functions

2021 ◽  
Vol 9 ◽  
Author(s):  
Selina K. Jorch ◽  
Carsten Deppermann
Keyword(s):  
3D Imaging ◽  
Immune Cell ◽  
Imaging Techniques ◽  
Innate Immune ◽  
Cell Behavior ◽  
Immune Functions ◽  
Interaction Partners ◽  
Organ Specific ◽  
Insight Into ◽  
Spinning Disc

Leukocytes are among the most mobile and versatile cells that have many essential functions in homeostasis and survival. Especially cells from the innate immune system, i.e., neutrophils and macrophages, play an important role as rapid first responders against invading microorganisms. With the advent of novel imaging techniques, new ways of visualizing innate immune cells have become available in recent years, thereby enabling more and more detailed discoveries about their nature, function and interaction partners. Besides intravital spinning-disc and 2-photon microscopy, clearing and 3D-imaging techniques provide new insights into the mechanism of innate immune cell behavior in their natural environment. This mini review focuses on the contributions of novel-imaging techniques to provide insight into the functions of neutrophils and macrophages under homeostasis and in infections. Imaging setups for different organs like the liver, kidney, heart, lung, and the peritoneal cavity are discussed as well as the current limitations of these imaging techniques.

Skin‐ny deeping: Uncovering immune cell behavior and function through imaging techniques*

2021 ◽  
Author(s):  
Yingrou Tan ◽  
Hong Liang Tey ◽  
Shu Zhen Chong ◽  
Lai Guan Ng
Keyword(s):  
Immune Cell ◽  
Imaging Techniques ◽  
Cell Behavior ◽  
And Function

scholarly journals Drosophila immune cells extravasate from vessels to wounds using Tre1 GPCR and Rho signaling

2018 ◽  
Vol 217 (9) ◽  
pp. 3045-3056 ◽  
Author(s):  
Leila Thuma ◽  
Deborah Carter ◽  
Helen Weavers ◽  
Paul Martin
Keyword(s):  
Immune Cells ◽  
Immune Cell ◽  
Innate Immune ◽  
Murine Models ◽  
Pupal Development ◽  
Epithelial Migration ◽  
Drosophila Model ◽  
Rate Limiting ◽  
Insight Into

Inflammation is pivotal to fight infection, clear debris, and orchestrate repair of injured tissues. Although Drosophila melanogaster have proven invaluable for studying extravascular recruitment of innate immune cells (hemocytes) to wounds, they have been somewhat neglected as viable models to investigate a key rate-limiting component of inflammation—that of immune cell extravasation across vessel walls—due to their open circulation. We have now identified a period during pupal development when wing hearts pulse hemolymph, including circulating hemocytes, through developing wing veins. Wounding near these vessels triggers local immune cell extravasation, enabling live imaging and correlative light-electron microscopy of these events in vivo. We show that RNAi knockdown of immune cell integrin blocks diapedesis, just as in vertebrates, and we uncover a novel role for Rho-like signaling through the GPCR Tre1, a gene previously implicated in the trans-epithelial migration of germ cells. We believe this new Drosophila model complements current murine models and provides new mechanistic insight into immune cell extravasation.

scholarly journals Flavored e-cigarette liquids and cinnamaldehyde impair respiratory innate immune cell function

2017 ◽  
Vol 313 (2) ◽  
pp. L278-L292 ◽  
Author(s):  
Phillip W. Clapp ◽  
Erica A. Pawlak ◽  
Justin T. Lackey ◽  
James E. Keating ◽  
Steven L. Reeber ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Nk Cells ◽  
Cell Function ◽  
Immune Cell ◽  
Innate Immune ◽  
Neutrophil Extracellular Trap ◽  
Immune Functions ◽  
Immune Cell Function ◽  
Functional Responses ◽  
Macrophage Phagocytosis

Innate immune cells of the respiratory tract are the first line of defense against pathogenic and environmental insults. Failure of these cells to perform their immune functions leaves the host susceptible to infection and may contribute to impaired resolution of inflammation. While combustible tobacco cigarettes have been shown to suppress respiratory immune cell function, the effects of flavored electronic cigarette liquids (e-liquids) and individual flavoring agents on respiratory immune cell responses are unknown. We investigated the effects of seven flavored nicotine-free e-liquids on primary human alveolar macrophages, neutrophils, and natural killer (NK) cells. Cells were challenged with a range of e-liquid dilutions and assayed for their functional responses to pathogenic stimuli. End points included phagocytic capacity (neutrophils and macrophages), neutrophil extracellular trap formation, proinflammatory cytokine production, and cell-mediated cytotoxic response (NK cells). E-liquids were then analyzed via mass spectrometry to identify individual flavoring components. Three cinnamaldehyde-containing e-liquids exhibited dose-dependent broadly immunosuppressive effects. Quantitative mass spectrometry was used to determine concentrations of cinnamaldehyde in each of the three e-liquids, and cells were subsequently challenged with a range of cinnamaldehyde concentrations. Cinnamaldehyde alone recapitulated the impaired function observed with e-liquid exposures, and cinnamaldehyde-induced suppression of macrophage phagocytosis was reversed by addition of the small-molecule reducing agent 1,4-dithiothreitol. We conclude that cinnamaldehyde has the potential to impair respiratory immune cell function, illustrating an immediate need for further toxicological evaluation of chemical flavoring agents to inform regulation governing their use in e-liquid formulations.

scholarly journals An Evaluation of the Fasciola hepatica miRnome Predicts a Targeted Regulation of Mammalian Innate Immune Responses

2021 ◽  
Vol 11 ◽  
Author(s):  
Alison Ricafrente ◽  
Hieu Nguyen ◽  
Nham Tran ◽  
Sheila Donnelly
Keyword(s):  
Immune Responses ◽  
Immune Cell ◽  
Fasciola Hepatica ◽  
Innate Immune ◽  
Innate Immune Responses ◽  
Regulate Gene Expression ◽  
Non Coding Rnas ◽  
Parasitic Worms ◽  
High Degree ◽  
Insight Into

Understanding mechanisms by which parasitic worms (helminths) control their hosts’ immune responses is critical to the development of effective new disease interventions. Fasciola hepatica, a global scourge of humans and their livestock, suppresses host innate immune responses within hours of infection, ensuring that host protective responses are quickly incapacitated. This allows the parasite to freely migrate from the intestine, through the liver to ultimately reside in the bile duct, where the parasite establishes a chronic infection that is largely tolerated by the host. The recent identification of micro(mi)RNA, small RNAs that regulate gene expression, within the extracellular vesicles secreted by helminths suggest that these non-coding RNAs may have a role in the parasite-host interplay. To date, 77 miRNAs have been identified in F. hepatica comprising primarily of ancient conserved species of miRNAs. We hypothesized that many of these miRNAs are utilized by the parasite to regulate host immune signaling pathways. To test this theory, we first compiled all of the known published F. hepatica miRNAs and critically curated their sequences and annotations. Then with a focus on the miRNAs expressed by the juvenile worms, we predicted gene targets within human innate immune cells. This approach revealed the existence of targets within every immune cell, providing evidence for the universal management of host immunology by this parasite. Notably, there was a high degree of redundancy in the potential for the parasite to regulate the activation of dendritic cells, eosinophils and neutrophils, with multiple miRNAs predicted to act on singular gene targets within these cells. This original exploration of the Fasciola miRnome offers the first molecular insight into mechanisms by which F. hepatica can regulate the host protective immune response.

scholarly journals CD47 and thrombospondin-1 regulation of mitochondria, metabolism, and diabetes

2021 ◽  
Author(s):  
David D. Roberts ◽  
Jeffrey S. Isenberg
Keyword(s):  
Immune Cell ◽  
Cell Types ◽  
Innate Immune ◽  
Cell Behavior ◽  
Metabolic Dysfunction ◽  
Endocrine Dysfunction ◽  
High Affinity ◽  
Thrombospondin 1 ◽  
Health And Disease ◽  
Self Antigen

Thrombospondin-1 (TSP1) is the prototypical member of a family of secreted proteins that modulate cell behavior by engaging with molecules in the extracellular matrix and with receptors on the cell surface. CD47 is widely displayed on many, if not all, cell types and is a high affinity TSP1 receptor. CD47 is a self-antigen that limits innate immune cell activities, a feature recently exploited to enhance cancer immunotherapy. Another major role for CD47 in health and disease is to mediate TSP1 signaling. TSP1 acting through CD47 contributes to mitochondrial, metabolic and endocrine dysfunction. Studies in animal models found that elevated TSP1 expression, acting in part through CD47, causes mitochondrial and metabolic dysfunction. Clinical studies established that abnormal TSP1 expression positively correlates with obesity, fatty liver disease and diabetes. The unabated increase in these conditions worldwide and the availability of CD47 targeting drugs justify a closer look into how TSP1 and CD47 disrupt metabolic balance and the potential for therapeutic intervention.

scholarly journals Neutrophils: Need for Standardized Nomenclature

2021 ◽  
Vol 12 ◽  
Author(s):  
Ellen McKenna ◽  
Aisling Ui Mhaonaigh ◽  
Richard Wubben ◽  
Amrita Dwivedi ◽  
Tim Hurley ◽  
...  
Keyword(s):  
Immune Cell ◽  
Expression Profiles ◽  
Suppressor Cells ◽  
Surface Marker ◽  
Innate Immune ◽  
Polymorphonuclear Neutrophils ◽  
Myeloid Derived Suppressor Cells ◽  
Surface Marker Expression ◽  
Tumor Associated Neutrophils ◽  
Insight Into

Neutrophils are the most abundant innate immune cell with critical anti-microbial functions. Since the discovery of granulocytes at the end of the nineteenth century, the cells have been given many names including phagocytes, polymorphonuclear neutrophils (PMN), granulocytic myeloid derived suppressor cells (G-MDSC), low density neutrophils (LDN) and tumor associated neutrophils (TANS). This lack of standardized nomenclature for neutrophils suggest that biologically distinct populations of neutrophils exist, particularly in disease, when in fact these may simply be a manifestation of the plasticity of the neutrophil as opposed to unique populations. In this review, we profile the surface markers and granule expression of each stage of granulopoiesis to offer insight into how each stage of maturity may be identified. We also highlight the remarkable surface marker expression profiles between the supposed neutrophil populations.

Live Imaging Innate Immune Cell Behavior During Normal Development, Wound Healing and Infection

2010 ◽  
pp. 129-148
Author(s):  
Chris Hall ◽  
Maria Vega Flores ◽  
Makoto Kamei ◽  
Kathryn Crosier ◽  
Phil Crosier
Keyword(s):  
Wound Healing ◽  
Normal Development ◽  
Immune Cell ◽  
Live Imaging ◽  
Innate Immune ◽  
Innate Immune Cell ◽  
Cell Behavior

scholarly journals Olfactomedin 4 marks a subset of neutrophils in mice

2018 ◽  
Vol 25 (1) ◽  
pp. 22-33 ◽  
Author(s):  
Matthew N Alder ◽  
Jaya Mallela ◽  
Amy M Opoka ◽  
Patrick Lahni ◽  
David A Hildeman ◽  
...  
Keyword(s):  
Innate Immune System ◽  
Immune Cell ◽  
Neutrophil Extracellular Traps ◽  
Innate Immune ◽  
Human Neutrophils ◽  
Null Mouse ◽  
Immune Functions ◽  
Single Population ◽  
Extracellular Traps ◽  
Neutrophil Differentiation

Neutrophils are the most abundant immune cell of the innate immune system and participate in essential immune functions. Heterogeneity within neutrophils has been documented, but it is difficult to distinguish if these are altered activation states of a single population or separate subpopulations of neutrophils determined at the time of differentiation. Several groups have identified a subset of human neutrophils that express olfactomedin 4 (OLFM4) and increased OLFM4+ neutrophils during sepsis is correlated with worse outcome, suggesting these neutrophils or the OLFM4 they secrete may be pathogenic. We tested if mice could be used as a model to study OLFM4+ neutrophils. We found the OLFM4 expressing subset of neutrophils is conserved in mice. Depending on the strain, 7–35% of murine neutrophils express OLFM4 and expression is determined early in neutrophil differentiation. OLFM4+ neutrophils phagocytose and transmigrate with similar efficiency as OLFM4− neutrophils. Here we show that within neutrophil extracellular traps (NETs) OLFM4+ and OLFM4− neutrophils undergo NETosis and OLFM4 colocalizes. Finally, we generated an OLFM4 null mouse and show that these mice are protected from death when challenged with sepsis, providing further evidence that the OLFM4 expressing subpopulation of neutrophils, or the OLFM4 they secrete, may be pathogenic during overwhelming infection.

Novel Innate Immune Functions Revealed by Dynamic, Real-Time Live Imaging of Bacterial Infections

2010 ◽  
Vol 30 (2) ◽  
pp. 107-117 ◽  
Author(s):  
Keira Melican ◽  
Jorrit Boekel ◽  
Monica Ryden-Aulin ◽  
Agneta Richter-Dahlfors
Keyword(s):  
Real Time ◽  
Bacterial Infections ◽  
Live Imaging ◽  
Innate Immune ◽  
Immune Functions

From the Inside Out: Practical Application of 3D Imaging Techniques in Art Conservation

2018 ◽  
Vol 2018 (1) ◽  
pp. 151-156
Author(s):  
Scott Geffert ◽  
Daniel Hausdorf ◽  
Joseph Coscia ◽  
Oi-Cheong Lee ◽  
Dahee Han ◽  
...  
Keyword(s):  
3D Imaging ◽  
Imaging Techniques ◽  
Art Conservation ◽  
Practical Application ◽  
Inside Out ◽  
3D Imaging Techniques
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