scholarly journals Transendothelial migration induces differential migration dynamics of leukocytes in tissue matrix

2021 ◽  
Author(s):  
Abraham C.I. van Steen ◽  
Lanette Kempers ◽  
Rouven Schoppmeyer ◽  
Max Blokker ◽  
David J Beebe ◽  
...  
Keyword(s):  
T Cells ◽  
Real Time ◽  
High Speed ◽  
Cell Tracking ◽  
The Matrix ◽  
Migration Dynamics ◽  
Leukocyte Extravasation ◽  
Tissue Matrix ◽  
Actin Remodelling

Leukocyte extravasation into inflamed tissue is a complex process that is difficult to capture as a whole in vitro. We employed a blood-vessel-on-a-chip model in which endothelial cells were cultured in a tube-like lumen in a collagen-1 matrix. The vessels are leak-tight, creating a barrier for molecules and leukocytes. Addition of inflammatory cytokine TNF-α caused vasoconstriction, actin remodelling and upregulation of ICAM-1. Introducing leukocytes into the vessels allowed real-time visualisation of leukocyte migration across the vessel wall, into the extracellular matrix. Individual cell tracking over time distinguished striking differences in migratory behaviour between T-cells and neutrophils. Neutrophils cross the endothelial layer more efficiently than T-cells, but upon entering the matrix, neutrophils display high speed but low persistence, whereas T-cells migrate with low speed and rather linear migration. In conclusion, 3D imaging in real-time of leukocyte extravasation in a vessel-on-a-chip enables detailed qualitative and quantitative analysis of different stages of the full leukocyte extravasation process in a single assay.

scholarly journals Transendothelial migration induces differential migration dynamics of leukocytes in tissue matrix

2021 ◽  
Author(s):  
Abraham C. I. van Steen ◽  
Lanette Kempers ◽  
Rouven Schoppmeyer ◽  
Max Blokker ◽  
David J. Beebe ◽  
...  
Keyword(s):  
T Cells ◽  
Real Time ◽  
High Speed ◽  
Cell Tracking ◽  
The Matrix ◽  
Migration Dynamics ◽  
Leukocyte Extravasation ◽  
Tissue Matrix ◽  
Actin Remodelling

Leukocyte extravasation into inflamed tissue is a complex process that is difficult to capture as a whole in vitro. We employed a blood-vessel-on-a-chip model in which endothelial cells were cultured in a tube-like lumen in a collagen-1 matrix. The vessels are leak-tight, creating a barrier for molecules and leukocytes. Addition of inflammatory cytokine TNF-α caused vasoconstriction, actin remodelling and upregulation of ICAM-1. Introducing leukocytes into the vessels allowed real-time visualisation of all different steps of the leukocyte transmigration cascade including migration into the extracellular matrix. Individual cell tracking over time distinguished striking differences in migratory behaviour between T-cells and neutrophils. Neutrophils cross the endothelial layer more efficiently than T-cells, but upon entering the matrix, neutrophils display high speed but low persistence, whereas T-cells migrate with low speed and rather linear migration. In conclusion, 3D imaging in real-time of leukocyte extravasation in a vessel-on-a-chip enables detailed qualitative and quantitative analysis of different stages of the full leukocyte extravasation process in a single assay.

Chemokines expressed in melanoma metastases associated with T cell infiltration

2007 ◽  
Vol 25 (18_suppl) ◽  
pp. 8501-8501 ◽  
Author(s):  
T. Gajewski ◽  
Y. Meng ◽  
H. Harlin
Keyword(s):  
Immune Response ◽  
T Cells ◽  
T Cell ◽  
Real Time ◽  
Cell Lines ◽  
Protein Array ◽  
Rt Pcr ◽  
Effector Phase ◽  
Melanoma Metastases

8501 Background: Despite frequent induction of tumor antigen-specific T cells in melanoma patients following vaccination, tumor regressions remain rare. This observation prompted systematic analysis of the melanoma tumor microenvironment to identify factors that may influence the effector phase of the anti-tumor immune response. Methods: Gene expression profiling using the Affymetrix platform was performed on a series of melanoma metastases, melanoma cell lines, and primary melanocyte cell lines. Confirmatory assays were done by real-time RT-PCR, protein array, immunohistochemistry (IHC), and in vitro chemokine migration assays. Results: Non- supervised hierarchical clustering revealed 3 major subsets of tumors, with the main clustering based on differential expression of T cell-derived transcripts. The presence of CD8+ T cells was confirmed by IHC. Tumors that contained T cells uniquely expressed high levels of multiple chemokines. Protein array confirmed high expression of CCL2, CCL4, and CCL5; real-time RT-PCR additionally confirmed relatively high levels of CXCL9, CXCL10, and CCL3 transcripts. Transwell assays confirmed that each of these 6 chemokines recruited CD8+ effector cells in vitro. Conclusions: We have identified a set of 6 chemokines that likely regulates recruitment of activated T cells into melanoma metastases. Tumors that lack such chemokines might not be capable of supporting the effector phase of the anti-tumor immune response. We suggest that chemokine profiling of tumor sites should be performed in clinical trials of active immunotherapy. No significant financial relationships to disclose.

scholarly journals Real-time analysis of T cell receptors in naive cells in vitro and in vivo reveals flexibility in synapse and signaling dynamics

2010 ◽  
Vol 207 (12) ◽  
pp. 2733-2749 ◽  
Author(s):  
Rachel S. Friedman ◽  
Peter Beemiller ◽  
Caitlin M. Sorensen ◽  
Jordan Jacobelli ◽  
Matthew F. Krummel
Keyword(s):  
Immune Response ◽  
T Cells ◽  
T Cell ◽  
Real Time ◽  
T Cell Activation ◽  
Valuable Insight ◽  
Time Dynamics ◽  
Insight Into

The real-time dynamics of the T cell receptor (TCR) reflect antigen detection and T cell signaling, providing valuable insight into the evolving events of the immune response. Despite considerable advances in studying TCR dynamics in simplified systems in vitro, live imaging of subcellular signaling complexes expressed at physiological densities in intact tissues has been challenging. In this study, we generated a transgenic mouse with a TCR fused to green fluorescent protein to provide insight into the early signaling events of the immune response. To enable imaging of TCR dynamics in naive T cells in the lymph node, we enhanced signal detection of the fluorescent TCR fusion protein and used volumetric masking with a second fluorophore to mark the T cells expressing the fluorescent TCR. These in vivo analyses and parallel experiments in vitro show minimal and transient incorporation of TCRs into a stable central supramolecular activating cluster (cSMAC) structure but strong evidence for rapid, antigen-dependent TCR internalization that was not contingent on T cell motility arrest or cSMAC formation. Short-lived antigen-independent TCR clustering was also occasionally observed. These in vivo observations demonstrate that varied TCR trafficking and cell arrest dynamics occur during early T cell activation.

scholarly journals Time Lapse Observation Based Modeling and Identification of Cell Behaviors in Angiogenic Sprout Development

2010 ◽  
Author(s):  
Levi B. Wood ◽  
Roger D. Kamm ◽  
H. Harry Asada
Keyword(s):  
Blood Vessel ◽  
Real Time ◽  
Time Lapse ◽  
Model Parameters ◽  
Cell Behaviors ◽  
The Matrix ◽  
The Individual ◽  
Sprout Formation ◽  
Cell Motion

This paper presents a method for deriving dynamic equations for Endothelial Cell (EC) motion and estimating parameters based on time lapse imagery of angiogenic sprout development. Angiogenesis is the process whereby a collection of endothelial cells sprout out from an existing blood vessel, degrade the surrounding scaffold and form a new blood vessel. Sprout formation requires that a collection of ECs all work together and coordinate their movements and behaviors. The process is initiated and guided by a collection of external growth factors. In addition, the individual cells communicate and respond to each other’s movements to behave in a coordinated fashion. The mechanics of cell coordination are extremely complex and include both chemical and mechanical communication between cells and between cells and the matrix. Despite the complexity of the physical system, with many variables that cannot be measured in real time, the ECs behave in a predictable manner based on just a few quantities that can be measured in real time. This work presents a methodology for constructing a set of simple stochastic equations for cell motion dependent only on quantities obtained from time lapse data observed from in vitro experiments. Model parameters are identified from time lapse data using a Maximum Likelihood Estimator.

scholarly journals CD137 Agonist Induces Gastric Cancer Cell Apoptosis by Enhancing The Functions of CD8+ T Cells via NF-κB Signaling

2020 ◽  
Author(s):  
Ben-Shun Hu ◽  
Tian Tang ◽  
Tie-Long Wu ◽  
Ying-Yue Sheng ◽  
Yu-Zheng Xue
Keyword(s):  
Gastric Cancer ◽  
Flow Cytometry ◽  
T Cells ◽  
Real Time ◽  
Peripheral Blood ◽  
Cell Apoptosis ◽  
Nuclear Translocation ◽  
Granzyme B ◽  
Ifn Γ

Abstract Background: CD137 is identified as a target for tumor immunotherapy. However, the role of CD137 in gastric cancer (GC), especially in inducing GC cell apoptosis has not been studied yet. Methods: Foxp3+ and CD8+ T cells in GCs were investigated by immunohistochemistry (IHC). CD137 expression in GCs was detected by flow cytometry, IHC and immunofluorescence (IF). Peripheral blood mononuclear cells (PBMCs) and CD8+ T cells isolated from peripheral blood were stimulated with a CD137 agonist in vitro. CD8+ T cells proliferation and p65 expression were explored by flow cytometry. p65 nuclear translocation was analyzed by IF. IL-10, TGF-β, IFN-γ, Perforin and Granzyme B were detected by real-time quantitative PCR (real-time PCR). PBMCs and primary GC cells were cocultured and stimulated with the CD137 agonist in vitro. Apoptosis of the primary GC cells was detected by flow cytometry. Results: Our data demonstrated that GC tumors show characteristics of an immunosuppressive microenvironment. CD137 was predominantly expressed in CD8+ T cells in GCs and had a positive correlation with tumor cell differentiation. CD137 agonist promoted CD8+ T cells proliferation and increased the secretion of IFN-γ, Perforin and Granzyme B, which induced primary GC cell apoptosis. Mechanistically, this study found that CD137 agonist could induce NF-κB nuclear translocation in CD8+ T cells. Conclusion: Our results demonstrate that CD137 agonist can induce primary GC cell apoptosis by enhancing CD8+ T cells via activating NF-κB signaling.

The matrix protein pp65341-350 : a peptide that induces ex vivo stimulation and in vitro expansion of CMV-specific CD8+ T cells in subjects bearing either HLA-A*2402 or A*0101 allele

Transfusion ◽  
2003 ◽  
Vol 43 (11) ◽  
pp. 1567-1574 ◽  
Author(s):  
Maurizio Provenzano ◽  
Jong-Baeck Lim ◽  
Simone Mocellin ◽  
Vladia Monsurro ◽  
Maria Bettinotti ◽  
...  
Keyword(s):  
T Cells ◽  
Cd8 T Cells ◽  
Matrix Protein ◽  
Ex Vivo ◽  
The Matrix ◽  
In Vitro Expansion

scholarly journals Comparative Study of Senescent Th Biomarkers in Healthy Donors and Early Arthritis Patients. Analysis of VPAC Receptors and Their Influence

Cells ◽  
2020 ◽  
Vol 9 (12) ◽  
pp. 2592
Author(s):  
Raúl Villanueva-Romero ◽  
Amalia Lamana ◽  
Marissa Flores-Santamaría ◽  
Mar Carrión ◽  
Selene Pérez-García ◽  
...  
Keyword(s):  
T Cells ◽  
Real Time ◽  
Real Time Pcr ◽  
Mutual Influence ◽  
Early Arthritis ◽  
Mineral Density ◽  
Th Cells ◽  
Vpac Receptors

Pro-inflammatory CD4+CD28− T cells are characteristic of immunosenescence, but also of several autoimmune/inflammatory diseases. Vasoactive intestinal peptide (VIP) acts as an anti-inflammatory and immunomodulatory mediator on these cells. Our objective was to study the mutual influence between senescent Th cells and VIP axis in early arthritis (EA), comparing with non-EA donors. We characterized the correlation between senescent Th cells and clinic parameters of EA as well as the behavior of senescent Th biomarkers by real-time PCR. Clinical data were systematically recorded at baseline and after 6 months of follow-up. The number of CD4+CD28− T cells measured by sorting is higher in patients who initially meet ACR classification criteria for rheumatoid arthritis (RA) compared to those who were classified as undifferentiated arthritis (UA). A slight positive correlation between EA CD4+CD28− T cells and CRP or ESR and a negative correlation with bone mineral density were found. Th senescent biomarkers in EA CD4+CD28− T cells were similar to donors, however some of them increased after 6 months of follow-up. VPAC receptors were analyzed by real-time PCR and immunofluorescence, and CD4+CD28− T cells showed higher expression of VPAC2 and lower of VPAC1, VPAC2 showing a significant increased expression in EA cells. Sorted CD4+CD28− T cells were in vitro expanded in presence of VIP, wherein VIP increased senescent biomarker CD27, while it diminished CD57 or NKG2 senescent biomarkers. Our study demonstrates for the first time the existence of a link between senescent Th cells and the VIP axis.

scholarly journals Leukocytes from Patients with Drug-Sensitive and Multidrug-Resistant Tuberculosis Exhibit Distinctive Profiles of Chemokine Receptor Expression and Migration Capacity

2021 ◽  
Vol 2021 ◽  
pp. 1-19
Author(s):  
Ranferi Ocaña-Guzmán ◽  
Norma A. Téllez-Navarrete ◽  
Lucero A. Ramón-Luing ◽  
Iliana Herrera ◽  
Marlon De Ita ◽  
...  
Keyword(s):  
T Cells ◽  
Plasma Levels ◽  
Immune Cell ◽  
Multidrug Resistant ◽  
Pharmacological Therapy ◽  
Receptor Expression ◽  
Mdr Tb ◽  
Migration Dynamics ◽  
Migration Capacity

Tuberculosis (TB), caused by Mycobacterium tuberculosis (Mtb), remains as a leading infectious cause of death worldwide. The increasing number of multidrug-resistant TB (MDR-TB) cases contributes to the poor control of the TB epidemic. Currently, little is known about the immunological requirements of protective responses against MDR-TB. This is of major relevance to identify immune markers for treatment monitoring and targets for adjuvant immunotherapies. Here, we hypothesized that MDR-TB patients display unique immunophenotypical features and immune cell migration dynamics compared to drug-sensitive TB (DS-TB). Hence, we prospectively conducted an extensive characterization of the immune profile of MDR-TB patients at different time points before and after pharmacological therapy. For this purpose, we focused on the leukocyte expression of chemokine receptors, distribution of different monocyte and lymphocyte subsets, plasma levels of chemotactic factors, and in vitro migration capacity of immune cells. Our comparative cohort consisted of DS-TB patients and healthy volunteer donors (HD). Our results demonstrate some unique features of leukocyte migration dynamics during MDR-TB. These include increased and prolonged circulation of CD3+ monocytes, CCR4+ monocytes, EM CD4+ T cells, EM/CM CD8+ T cells, and CXCR1+CXCR3+ T cells that is sustained even after the administration of anti-TB drugs. We also observed shared characteristics of both MDR-TB and DS-TB that include CCR2+ monocyte depletion in the blood; high plasma levels of MPC-1, CCL-7, and IP-10; and increased responsiveness of leukocytes to chemotactic signals in vitro. Our study contributes to a better understanding of the MDR-TB pathobiology and uncovers immunological readouts of treatment efficacy.

Reflection Coefficients at Collagen Interfaces in Soft Tissues

1979 ◽  
Vol 1 (4) ◽  
pp. 346-355 ◽  
Author(s):  
Avtar S. Ahuja
Keyword(s):  
Normal Tissue ◽  
Elastic Moduli ◽  
Soft Tissues ◽  
Reflection Coefficients ◽  
Body Model ◽  
The Matrix ◽  
Correlation Parameters ◽  
Tissue Matrix ◽  
Amplitude Reflection

For the purpose of ultrasonic imaging, soft tissue has been modeled as a viscoelastic (Voigt) composite material consisting of collagen fibers (as the inhomogeneity) embedded in a continuum tissue (as the matrix). It is known that infarction enhances the collagen content in myocardial tissues. The published in vitro attenuation data in normal and infarcted myocardial tissues have been correlated with the Voigt body model. From the correlation parameters and mixture laws for the elastic moduli of tissue components, the bulk modulus of collagen has been estimated to be about 50–55% higher than that of the normal tissue. From a knowledge of the bulk moduli and mass densities of collagen and tissue matrix, amplitude reflection coefficients at collagen interfaces have been computed. The amplitude reflection coefficient at the saline-collagen or at the collagen-myocardium interface is about 6 times that at the saline-myocardium interface.

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