Deletion of Alloreactive T Cells by Veto Cytotoxic T Lymphocytes Is Mediated Through Extracellular Signal-Regulated Kinase Phosphorylation

2010 ◽  
Vol 90 (4) ◽  
pp. 380-386 ◽  
Author(s):  
Shlomit Reich-Zeliger ◽  
Yaki Eidelstein ◽  
David Hagin ◽  
Yaron E. Antebi ◽  
Rony Seger ◽  
...  
Keyword(s):  
T Cells ◽  
T Lymphocytes ◽  
Cytotoxic T Lymphocytes ◽  
Extracellular Signal Regulated Kinase ◽  
Alloreactive T Cells ◽  
Extracellular Signal ◽  
Kinase Phosphorylation

scholarly journals Peptide-independent Recognition by Alloreactive Cytotoxic T Lymphocytes (CTL)

1997 ◽  
Vol 185 (6) ◽  
pp. 1023-1034 ◽  
Author(s):  
Pamela A. Smith ◽  
Anders Brunmark ◽  
Michael R. Jackson ◽  
Terry A. Potter
Keyword(s):  
T Cells ◽  
T Lymphocytes ◽  
Cytotoxic T Lymphocytes ◽  
Skin Graft ◽  
Antigen Processing ◽  
Cytotoxic T Cell ◽  
Target Cells ◽  
Mhc Molecules ◽  
Alloreactive T Cells

We have isolated several H-2Kb–alloreactive cytotoxic T cell clones and analyzed their reactivity for several forms of H-2Kb. These cytotoxic T lymphocytes (CTL) were elicited by priming with a skin graft followed by in vitro stimulation using stimulator cells that express an H-2Kb molecule unable to bind CD8. In contrast to most alloreactive T cells, these CTL were able to recognize H-2Kb on the surface of the antigen processing defective cell lines RMA-S and T2. Furthermore, this reactivity was not increased by the addition of an extract containing peptides from C57BL/6 (H-2b) spleen cells, nor was the reactivity decreased by treating the target cells with acid to remove peptides bound to MHC molecules. The CTL were also capable of recognizing targets expressing the mutant H-2Kbm8 molecule. These findings suggested that the clones recognized determinants on H-2Kb that were independent of peptide. Further evidence for this hypothesis was provided by experiments in which H-2Kb produced in Drosophila melanogaster cells and immobilized on the surface of a tissue culture plate was able to stimulate hybridomas derived from these alloreactive T cells. Precursor frequency analysis demonstrated that skin graft priming, whether with skin expressing the wild-type or the mutant H-2Kb molecule, is a strong stimulus to elicit peptide-independent CTL. Moreover, reconstitution experiments demonstrated that the peptide-independent CTL clones were capable of mediating rapid and complete rejection of H-2–incompatible skin grafts. These findings provide evidence that not all allorecognition is peptide dependent.

Selection of CD34+ HSC from Pooled Cord Blood Samples Does Not Result in Co-Purification of Potential Alloreactive CD3+ T Cells.

Blood ◽  
2005 ◽  
Vol 106 (11) ◽  
pp. 5263-5263
Author(s):  
Gary L. Gilmore ◽  
Darlene K. DePasquale ◽  
John Lister ◽  
Richard K. Shadduck
Keyword(s):  
Flow Cytometry ◽  
T Cells ◽  
T Lymphocytes ◽  
Cytotoxic T Lymphocytes ◽  
Ex Vivo ◽  
Blood Samples ◽  
Alloreactive T Cells ◽  
Pooled Samples ◽  
Cd34 Selection ◽  
Selection Of

Abstract Most systems for studying the ex vivo expansion of human UCB-HSC require enrichment of the HSC population, typically by CD34 selection. Because the number of HSC present in a single UCB collection is limited, one approach to increase the total HSC is to pool multiple UCB samples. A potential complicating factor with this method is that alloreactive T lymphocytes present in whole UCB samples would be expected to bind to cells displaying allogeneic HLA, including HSC, and would therefore co-purify with CD34+ UCB-HSC during isolation. Such complexes would be excluded from ISHAGE analysis by the side scatter gate, which is set to exclude aggregates. Alloreactive T cells would be expected to contain cytotoxic T lymphocytes [CTL], which could potentially inhibit or completely abrogate HSC expansion. In order to determine whether CD3+ T lymphocytes co-purify with CD34+ UCB-HSC in pooled samples, UCB pools were prepared containing 2 to 4 UCB samples. CD34+ HSC were isolated by MACS and analyzed by flow cytometry and antibodies to human CD45, CD34 and CD3, with and without ISHAGE gates. Samples of CD34+ HSC purified from a single UCB collection were analyzed concurrently to give the background value for co-purification of syngeneic T cells and formation of T:HSC aggregates in the CD34-selected products. We found a limited number of CD3+ T cells present in CD34+ HSC isolated from single UCB collections [mean = 0.25%, range = 0 – 1.1%]. That value was slightly elevated when pools of UCB were used [mean = 0.44%; range = 0 – 1.9%]. There are few, if any, CD34+/CD3+ cells that can be detected by either the standard ISHAGE gating or by gating merely on CD45+ cells with no side scatter gating [0.02 – 0.04%]. This was true of CD34+ HSC isolated from either pooled UCB or single UCB collections. Based on these results, we conclude that there is not significant co-purification of CD3+ T cells with CD34+ UCB-HSC, and that any such complexes that form are not found at any greater frequency in UCB pools than in single UCB collections.

scholarly journals CCR7/CCL19 Controls Expression of EDG-1 in T Cells

2012 ◽  
Vol 287 (15) ◽  
pp. 11656-11664 ◽  
Author(s):  
Laura A. Shannon ◽  
Tiffany M. McBurney ◽  
Melissa A. Wells ◽  
Megan E. Roth ◽  
Psachal A. Calloway ◽  
...  
Keyword(s):  
T Cells ◽  
T Lymphocytes ◽  
Lymph Nodes ◽  
Immune Functions ◽  
Extracellular Signal Regulated Kinase ◽  
Human T Cell ◽  
Extracellular Signal ◽  
Differentiation Gene ◽  
Human T Cell Line ◽  
Stimulation Of

T lymphocytes circulate between the blood, tissues, and lymph. These T cells carry out immune functions, using the C-C chemokine receptor 7 (CCR7) and its cognate ligands, CCL19 and CCL21, to enter and travel through the lymph nodes. Distinct roles for each ligand in regulating T lymphocyte trafficking have remained elusive. We report that in the human T cell line HuT78 and in primary murine T lymphocytes, signaling from CCR7/CCL19 leads to increased expression and phosphorylation of extracellular signal-regulated kinase 5 (ERK5) within eight hours of stimulation. Within 48–72 h we observed peak levels of endothelial differentiation gene 1 (EDG-1), which mediates the egress of T lymphocytes from lymph nodes. The increased expression of EDG-1 was preceded by up-regulation of its transcription factor, Krüppel-like factor 2 (KLF-2). To determine the cellular effect of disrupting ERK5 signaling from CCR7, we examined the migration of ERK5flox/flox/Lck-Cre murine T cells to EDG-1 ligands. While CCL19-stimulated ERK5flox/flox naïve T cells showed increased migration to EDG-1 ligands at 48 h, the migration of ERK5flox/flox/Lck-Cre T cells remained at a basal level. Accordingly, we define a novel signaling pathway that controls EDG-1 up-regulation following stimulation of T cells by CCR7/CCL19. This is the first report to link the two signaling events that control migration through the lymph nodes: CCR7 mediates entry into the lymph nodes and EDG-1 signaling controls their subsequent exit.

scholarly journals Metabolic radiolabeling and in vivo PET imaging of cytotoxic T lymphocytes to guide combination adoptive cell transfer cancer therapy

2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Dehua Lu ◽  
Yanpu Wang ◽  
Ting Zhang ◽  
Feng Wang ◽  
Kui Li ◽  
...  
Keyword(s):  
T Cells ◽  
T Lymphocytes ◽  
Solid Tumors ◽  
Cytotoxic T Lymphocytes ◽  
Pet Imaging ◽  
Stage Migration ◽  
Cell Transfer ◽  
Tumor Infiltration ◽  
Antitumor Effects

Abstract Background Adoptive T cell transfer-based immunotherapy yields unsatisfactory results in the treatment of solid tumors, partially owing to limited tumor infiltration and the immunosuppressive microenvironment in solid tumors. Therefore, strategies for the noninvasive tracking of adoptive T cells are critical for monitoring tumor infiltration and for guiding the development of novel combination therapies. Methods We developed a radiolabeling method for cytotoxic T lymphocytes (CTLs) that comprises metabolically labeling the cell surface glycans with azidosugars and then covalently conjugating them with 64Cu-1,4,7-triazacyclononanetriacetic acid-dibenzo-cyclooctyne (64Cu-NOTA-DBCO) using bioorthogonal chemistry. 64Cu-labeled control-CTLs and ovalbumin-specific CTLs (OVA-CTLs) were tracked using positron emission tomography (PET) in B16-OVA tumor-bearing mice. We also investigated the effects of focal adhesion kinase (FAK) inhibition on the antitumor efficacy of OVA-CTLs using a poly(lactic-co-glycolic) acid (PLGA)-encapsulated nanodrug (PLGA-FAKi). Results CTLs can be stably radiolabeled with 64Cu with a minimal effect on cell viability. PET imaging of 64Cu-OVA-CTLs enables noninvasive mapping of their in vivo behavior. Moreover, 64Cu-OVA-CTLs PET imaging revealed that PLGA-FAKi induced a significant increase in OVA-CTL infiltration into tumors, suggesting the potential for a combined therapy comprising OVA-CTLs and PLGA-FAKi. Further combination therapy studies confirmed that the PLGA-FAKi nanodrug markedly improved the antitumor effects of adoptive OVA-CTLs transfer by multiple mechanisms. Conclusion These findings demonstrated that metabolic radiolabeling followed by PET imaging can be used to sensitively profile the early-stage migration and tumor-targeting efficiency of adoptive T cells in vivo. This strategy presents opportunities for predicting the efficacy of cell-based adoptive therapies and for guiding combination regimens. Graphic Abstract

scholarly journals CD27 Expression Promotes Long-Term Survival of Functional Effector–Memory CD8+Cytotoxic T Lymphocytes in HIV-infected Patients

2004 ◽  
Vol 200 (11) ◽  
pp. 1407-1417 ◽  
Author(s):  
Adrian F. Ochsenbein ◽  
Stanley R. Riddell ◽  
Michele Brown ◽  
Lawrence Corey ◽  
Gabriela M. Baerlocher ◽  
...  
Keyword(s):  
T Cells ◽  
T Lymphocytes ◽  
Cytotoxic T Lymphocytes ◽  
Cd8 T Cells ◽  
Interleukin 2 ◽  
Tumor Necrosis Factor Receptor ◽  
Cell Receptor ◽  
Effector Memory ◽  
Term Survival ◽  
Functional Consequences

Human immunodeficiency virus (HIV)-specific CD8+ T cells persist in high frequencies in HIV-infected patients despite impaired CD4+ T helper response to the virus, but, unlike other differentiated effector cytotoxic T lymphocytes, most continue to express the tumor necrosis factor receptor family member CD27. Because the ligand for CD27 (CD70) is also overexpressed in HIV-infected hosts, we examined the nature of expression and potential functional consequences of CD27 expression on HIV-specific CD8+ T cells. Analysis of CD27+ and CD27− T cells derived from the same HIV-specific clone revealed that retention of CD27 did not interfere with acquisition of effector functions, and that after T cell receptor stimulation, CD27+ cells that concurrently were triggered via CD27 exhibited more resistance to apoptosis, interleukin 2 production, and proliferation than CD27− T cells. After transfer back into an HIV-infected patient, autologous HIV-specific CD27− T cells rapidly disappeared, but CD27+ T cells derived from the same clone persisted at high frequency. Our findings suggest that the CD27–CD70 interaction in HIV infection may provide CD27+ CD8+ T cells with a survival advantage and compensate for limiting or absent CD4+ T help to maintain the CD8 response.

scholarly journals EGF hijacks miR-198/FSTL1 wound-healing switch and steers a two-pronged pathway toward metastasis

2017 ◽  
Vol 214 (10) ◽  
pp. 2889-2900 ◽  
Author(s):  
Gopinath M. Sundaram ◽  
Hisyam M. Ismail ◽  
Mohsin Bashir ◽  
Manish Muhuri ◽  
Candida Vaz ◽  
...  
Keyword(s):  
Wound Healing ◽  
Wound Closure ◽  
Prognostic Significance ◽  
Competitive Inhibitor ◽  
Molecular Switch ◽  
Extracellular Signal Regulated Kinase ◽  
Keratinocyte Migration ◽  
Extracellular Signal ◽  
Single Transcript ◽  
Kinase Phosphorylation

Epithelial carcinomas are well known to activate a prolonged wound-healing program that promotes malignant transformation. Wound closure requires the activation of keratinocyte migration via a dual-state molecular switch. This switch involves production of either the anti-migratory microRNA miR-198 or the pro-migratory follistatin-like 1 (FSTL1) protein from a single transcript; miR-198 expression in healthy skin is down-regulated in favor of FSTL1 upon wounding, which enhances keratinocyte migration and promotes re-epithelialization. Here, we reveal a defective molecular switch in head and neck squamous cell carcinoma (HNSCC). This defect shuts off miR-198 expression in favor of sustained FSTL1 translation, driving metastasis through dual parallel pathways involving DIAPH1 and FSTL1. DIAPH1, a miR-198 target, enhances directional migration through sequestration of Arpin, a competitive inhibitor of Arp2/3 complex. FSTL1 blocks Wnt7a-mediated repression of extracellular signal–regulated kinase phosphorylation, enabling production of MMP9, which degrades the extracellular matrix and facilitates metastasis. The prognostic significance of the FSTL1-DIAPH1 gene pair makes it an attractive target for therapeutic intervention.

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