scholarly journals Demonstration of Direct Neurite–Osteoclastic Cell Communication In Vitro via the Adrenergic Receptor

2010 ◽  
Vol 112 (2) ◽  
pp. 184-191 ◽  
Author(s):  
Satoko Suga ◽  
Shigemi Goto ◽  
Akifumi Togari
Keyword(s):  
Adrenergic Receptor ◽  
Cell Communication ◽  
Osteoclastic Cell

scholarly journals ATRT-14. MACROPHAGE-TUMOR CELL INTERACTION PROMOTES ATRT PROGRESSION AND CHEMORESISTANCE

2020 ◽  
Vol 22 (Supplement_3) ◽  
pp. iii278-iii278
Author(s):  
Viktoria Melcher ◽  
Monika Graf ◽  
Marta Interlandi ◽  
Natalia Moreno ◽  
Flavia W de Faria ◽  
...  
Keyword(s):  
Tumor Cell ◽  
Tumor Cells ◽  
Chemotherapy Resistance ◽  
Cell Communication ◽  
Xenograft Model ◽  
Cell Interaction ◽  
Immunofluorescent Staining ◽  
Genetic Traits ◽  
Rhabdoid Tumors

Abstract Atypical teratoid/rhabdoid tumors (ATRT) are pediatric brain neoplasms that are known for their heterogeneity concerning pathophysiology and outcome. The three genetically rather uniform but epigenetically distinct molecular subgroups of ATRT alone do not sufficiently explain the clinical heterogeneity. Therefore, we examined the tumor microenvironment (TME) in the context of tumor diversity. By using multiplex-immunofluorescent staining and single-cell RNA sequencing (scRNA-seq) we unveiled the pan-macrophage marker CD68 as a subgroup-independent negative prognostic marker for survival of ATRT patients. ScRNA-seq analysis of murine ATRT-SHH, ATRT-MYC and extracranial RT (eRT) provide a delineation of the TME, which is predominantly infiltrated by myeloid cells: more specifically a microglia-enriched niche in ATRT-SHH and a bone marrow-derived macrophage infiltration in ATRT-MYC and eRT. Exploring the cell-cell communication of tumor cells with tumor-associated immune cells, we found that Cd68+ tumor-associated macrophages (TAMs) are central to intercellular communication with tumor cells. Moreover, we uncovered distinct tumor phenotypes in murine ATRT-MYC that share genetic traits with TAMs. These intermediary cells considerably increase the intratumoral heterogeneity of ATRT-MYC tumors. In vitro co-culture experiments recapitulated the capability of ATRT-MYC cells to interchange cell material with macrophages extensively, in contrast to ATRT-SHH cells. We found that microglia are less involved in the exchange of information with ATRT cells and that direct contact is a prerequisite for incorporation. A relapse xenograft model implied that intermediary cells are involved in the acquisition of chemotherapy resistance. We show evidence that TAM-tumor cell interaction is one mechanism of chemotherapy resistance and relapse in ATRT.

β-blockade abolishes the augmented cardiac tPA release induced by transactivation of heterodimerised bradykinin receptor-2 and β2-adrenergic receptor in vivo

2014 ◽  
Vol 112 (11) ◽  
pp. 951-959 ◽  
Author(s):  
Morten Eriksen ◽  
Arnfinn Ilebekk ◽  
Alessandro Cataliotti ◽  
Cathrine Rein Carlson ◽  
Torstein Lyberg ◽  
...  
Keyword(s):  
Adrenergic Receptor ◽  
Sympathetic Nerves ◽  
Ventricular Myocardium ◽  
Left Ventricular ◽  
Left Ventricular Myocardium ◽  
Adrenergic Stimulation ◽  
Β2 Adrenergic Receptor ◽  
Β Blocker

SummaryBradykinin (BK) receptor-2 (B2R) and β2-adrenergic receptor (β2AR) have been shown to form heterodimers in vitro. However, in vivo proofs of the functional effects of B2R-β2AR heterodimerisation are missing. Both BK and adrenergic stimulation are known inducers of tPA release. Our goal was to demonstrate the existence of B2R-β2AR heterodimerisation in myocardium and to define its functional effect on cardiac release of tPA in vivo. We further investigated the effects of a non-selective β-blocker on this receptor interplay. To investigate functional effects of B2R-β2AR heterodimerisation (i. e. BK transactivation of β2AR) in vivo, we induced serial electrical stimulation of cardiac sympathetic nerves (SS) in normal pigs that underwent concomitant BK infusion. Both SS and BK alone induced increases in cardiac tPA release. Importantly, despite B2R desensitisation, simultaneous BK infusion and SS (BK+SS) was characterised by 2.3 ± 0.3-fold enhanced tPA release compared to SS alone. When β-blockade (propranolol) was introduced prior to BK+SS, tPA release was inhibited. A persistent B2R-β2AR heterodimer was confirmed in BK-stimulated and nonstimulated left ventricular myocardium by immunoprecipitation studies and under non-reducing gel conditions. All together, these results strongly suggest BK transactivation of β2AR leading to enhanced β2AR-mediated release of tPA. Importantly, non-selective β-blockade inhibits both SS-induced release of tPA and the functional effects of B2R-β2AR heterodimerisation in vivo, which may have important clinical implications.

scholarly journals Cd40-Independent Pathways of T Cell Help for Priming of Cd8+ Cytotoxic T Lymphocytes

2000 ◽  
Vol 191 (3) ◽  
pp. 541-550 ◽  
Author(s):  
Zhengbin Lu ◽  
Lingxian Yuan ◽  
Xianzheng Zhou ◽  
Eduardo Sotomayor ◽  
Hyam I. Levitsky ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Cd4 T Cells ◽  
Cytotoxic T Lymphocyte ◽  
Cell Communication ◽  
Cd8 T Cell ◽  
Cd4 Help ◽  
T Cell Help

In many cases, induction of CD8+ CTL responses requires CD4+ T cell help. Recently, it has been shown that a dominant pathway of CD4+ help is via antigen-presenting cell (APC) activation through engagement of CD40 by CD40 ligand on CD4+ T cells. To further study this three cell interaction, we established an in vitro system using dendritic cells (DCs) as APCs and influenza hemagglutinin (HA) class I and II peptide–specific T cell antigen receptor transgenic T cells as cytotoxic T lymphocyte precursors and CD4+ T helper cells, respectively. We found that CD4+ T cells can provide potent help for DCs to activate CD8+ T cells when antigen is provided in the form of either cell lysate, recombinant protein, or synthetic peptides. Surprisingly, this help is completely independent of CD40. Moreover, CD40-independent CD4+ help can be documented in vivo. Finally, we show that CD40-independent T cell help is delivered through both sensitization of DCs and direct CD4+–CD8+ T cell communication via lymphokines. Therefore, we conclude that CD4+ help comprises at least three components: CD40-dependent DC sensitization, CD40-independent DC sensitization, and direct lymphokine-dependent CD4+–CD8+ T cell communication.

scholarly journals Molecular mimicry between the immunodominant ribosomal protein P0 of Trypanosoma cruzi and a functional epitope on the human beta 1-adrenergic receptor.

1995 ◽  
Vol 182 (1) ◽  
pp. 59-65 ◽  
Author(s):  
I Ferrari ◽  
M J Levin ◽  
G Wallukat ◽  
R Elies ◽  
D Lebesgue ◽  
...  
Keyword(s):  
Trypanosoma Cruzi ◽  
Adrenergic Receptor ◽  
Molecular Mimicry ◽  
Autoimmune Response ◽  
Extracellular Loop ◽  
Western Blots ◽  
Carboxy Terminal ◽  
Ribosomal Protein P0 ◽  
Positive Chronotropic Effect

Sera from chagasic patients possess antibodies recognizing the carboxy-terminal part of the ribosomal P0 protein of Trypanosoma cruzi and the second extracellular loop of the human beta 1-adrenergic receptor. Comparison of both peptides showed that they contain a pentapeptide with very high homology (AESEE in P0 and AESDE in the human beta 1-adrenergic receptor). Using a competitive immunoenzyme assay, recognition of the peptide corresponding to the second extracellular loop (H26R) was inhibited by both P0-14i (AAAESEEEDDDDDF) and P0-beta (AESEE). Concomitantly, recognition of P0-beta was inhibited with the H26R peptide. Recognition of P0 in Western blots was inhibited by P0-14i, P0-beta, and H26R, but not by a peptide corresponding to the second extracellular loop of the human beta 2-adrenergic receptor or by an unrelated peptide. Autoantibodies affinity purified with the immobilized H26R peptide were shown to exert a positive chronotropic effect in vitro on cardiomyocytes from neonatal rats. This effect was blocked by both the specific beta 1 blocker bisoprolol and the peptide P0-beta. These results unambiguously prove that T. cruzi is able to induce a functional autoimmune response against the cardiovascular human beta 1-adrenergic receptor through a molecular mimicry mechanism.

CD40 LIGAND MUTATIONS IN X-LINKED IMMUNODEFICIENCY WITH HYPER-IgM

PEDIATRICS ◽  
1994 ◽  
Vol 94 (2) ◽  
pp. 280-280
Author(s):  
Arden Levy ◽  
Andrew Liu
Keyword(s):  
T Cells ◽  
B Cells ◽  
Bacterial Infections ◽  
Point Mutations ◽  
Cell Communication ◽  
Cd40 Ligand ◽  
Research Groups ◽  
Immune Disorder ◽  
Hyper Igm

Purpose of the Studies. Hyper-IgM immunodeficiency is characterized by recurrent bacterial infections, normal or elevated IgM, and markedly decreased IgG, IgA, and IgE. Previous research suggested that the T cells of these patients are defective in their ability to help B cells make functional antibody. CD40 ligand (CD4OL) is a membrane glycoprotein on activated T helper cells and binds the CD40 molecule expressed on B cells, and induces proliferation and immunoglobulin class switching (in conjunction with IL-4). The gene for the CD4OL has been mapped to position q26.3-q27.1 on chromosome X (same as the Hyper-IgM gene and the area of isotype switching). Several research groups sought to determine if the immunodeficiency in Hyper-IgM patients is due to defective CD4OL. Findings. The five papers listed above document the work of different research groups that simultaneously found abnormalities in the CD4OL gene in a total of 16 patients with X-linked Hyper-IgM syndrome. Different mutations of the CD4OL gene have been discovered, including point mutations, deletions, and nonsense sequences. Mutant version of CD4OL taken from Hyper IgM patients were unable to "help" B cells in vitro. Thus, deficient CD40/CD40L interactions between B and T cells results in severely impaired immunity. Restricted CD40L gene expression to T cells may ultimately allow gene therapy as treatment. Reviewers' Comments. A concise editorial by Jean Marx entitled "Cell Communication Failure Leads to Immune Disorder" describes this landmark research and accompanies the Spriggs article in the February 12th issue of Science (pp. 896-897). This discovery may not only lead to treatment of this disorder, but also modification of other less favorable immune responses.

Abstract 17071: Cell Communication Inference in Macrophages

Circulation ◽  
2020 ◽  
Vol 142 (Suppl_3) ◽  
Author(s):  
Nika Taghdiri ◽  
Kevin R King ◽  
David Calcagno ◽  
Zhenxing Fu ◽  
Kenneth Huang ◽  
...  
Keyword(s):  
Image Analysis ◽  
Analytical Methods ◽  
Cell Injury ◽  
Diffusion Mechanism ◽  
Cell Communication ◽  
In Vivo Studies ◽  
Cell Dynamics ◽  
Calcium Indicator

Introduction: Tissue macrophages play diverse roles in the cardiovascular system during health and disease. They have diverse functions within tissues, but our understanding of their dynamics is limited because most macrophage characterization assays are destructive and have low temporal resolution. We asked whether these cells are dynamic and interconnected. Methods: Here, we describe experimental and analytical methods for measuring cell dynamics and inferring communication between cells in vitro and in vivo. We created a mouse (Csf1r-Cre x GCaMP5) expressing the Cre-inducible genetically encoded calcium indicator GCaMP5 under the regulation of the innate immune promoter, Csf1r, to non-destructively quantify high-frequency cell dynamics and differentiated them in culture using m-CSF. We developed custom image analysis routines and parameterization strategies for classifying calcium responses. Results: Our studies revealed that calcium reporter BMDMs display minimal fluctuations at baseline but exhibit a dynamic response to immunogenic DNA sensing. DNA-induced isolated cell injury and death, which precipitated cell communication that spread with a velocity of [9μm/s], consistent with an extracellular diffusion mechanism. We developed quantitative image analysis methods that corrected for random calcium fluctuations and identified statistically significant areas of correlated calcium changes suggestive of communication. An analytical pipeline enabled quantification of calcium spike dynamics and correlations of dynamic calcium profiles of single cell sharing a local microenvironment. This resulted in an “improbable synchrony” metric that allowed localization of communication in time and space. We adapted the pipeline for in vivo studies and tested them in a dorsal window chamber model using intravital microscopy. At 2Hz sampling frequency, we identified 27 potential communication events as they responded to complex microenvironmental cues in vivo. Conclusion: The experimental and analytical methods for inferring cell communication provide a new quantitative toolkit for investigating known as-yet undiscovered cell communication pathways.

scholarly journals Quantifying single-cell secretion in real time using resonant hyperspectral imaging

2018 ◽  
Vol 115 (52) ◽  
pp. 13204-13209 ◽  
Author(s):  
José Juan-Colás ◽  
Ian S. Hitchcock ◽  
Mark Coles ◽  
Steven Johnson ◽  
Thomas F. Krauss
Keyword(s):  
Single Cell ◽  
Real Time ◽  
Protein Secretion ◽  
Cell Communication ◽  
Label Free ◽  
Cell Secretion ◽  
Physiological Disorder ◽  
Real Time Analysis ◽  
Technology Heterogeneity

Cell communication is primarily regulated by secreted proteins, whose inhomogeneous secretion often indicates physiological disorder. Parallel monitoring of innate protein-secretion kinetics from individual cells is thus crucial to unravel systemic malfunctions. Here, we report a label-free, high-throughput method for parallel, in vitro, and real-time analysis of specific single-cell signaling using hyperspectral photonic crystal resonant technology. Heterogeneity in physiological thrombopoietin expression from individual HepG2 liver cells in response to platelet desialylation was quantified demonstrating how mapping real-time protein secretion can provide a simple, yet powerful approach for studying complex physiological systems regulating protein production at single-cell resolution.

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