TNF-Alpha Priming Enhances CD4+ FoxP3+ Regulatory T Cell Suppressive Function in GvHD Prevention and Treatment

Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. 1885-1885
Author(s):  
Antonio Pierini ◽  
Caitlin Moffett ◽  
Dominik Schneidawind ◽  
Jeanette Baker ◽  
Hidekazu Nishikii ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Mouse Model ◽  
Peripheral Blood ◽  
Activation Markers ◽  
Suppressive Function ◽  
Prevention And Treatment ◽  
And Function

Abstract CD4+ CD25+ FoxP3+ regulatory T cells (Treg) have been shown to effectively prevent graft versus host disease (GvHD) when adoptively transferred in murine models of hematopoietic cell transplantation (HCT) and phase I/II clinical trials. Critical limitations to the clinical application of Treg are the paucity of cells and limited knowledge of the mechanism(s) of in vivo function. In physiologic conditions Treg regulate immune responses during inflammation. We hypothesized that inflammatory conditions in GvHD modify Treg characteristics and function. To test this hypothesis, we primed Treg with irradiated (3000 cGy) peripheral blood from acute GvHD (aGvHD) affected mice for 20-24 hours and then transferred these cells in a mouse model of GvHD where allogeneic T cell depleted bone marrow (TCD BM) from C57BL/6 mice was transplanted into lethally irradiated (8 Gy) BALB/c recipients together with 7.5x105 to 1x106 /animal donor derived conventional CD4+ and CD8+ T cells (Tcon). C57BL/6 Treg primed with irradiated aGvHD peripheral blood were injected at day 0 after HCT for preventing GvHD or at day +7 or +8 as GvHD treatment. Their adoptive transfer resulted in improved survival in comparison to unprimed natural occurring Treg when used for both GvHD prevention (p=0.01) and treatment (p=0.04). Moreover treatment with irradiated aGvHD peripheral blood-primed Treg did not impact graft versus tumor effects in a mouse model of T cell mediated tumor killing. BLI demonstrated that injected allogeneic Tcon completely cleared previously infused luc+ A20 tumor cells even in the presence of primed Treg (primed Treg + Tcon + A20 vs A20 alone p<0.001). Irradiated aGvHD peripheral blood-primed Treg express increased levels of activation markers with suppressive function such as CTLA4 (p<0.001) and LAG3 (p<0.05) in comparison to unprimed Treg in vitro. We also found that Treg primed with irradiated cells of aGvHD affected animals after removing the serum did not enhance the expression of the same markers (p>0.05) demonstrating that serum from aGvHD animals is required for Treg priming and function. We further tested the ability of several inflammatory cytokines that are normally secreted during GvHD such as IFN-γ, IL-6, IL-12 and TNFα to induce similar in vitro Treg activation. We found that TNFɑ selectively activated Treg without impacting CD4+ FoxP3- T cells. TNFɑ-primed Treg have increased expression of activation markers such as CD69 (p<0.0001), CD25 (p<0.0001), and LAG3 (p=0.0002), produce a greater amount of suppressive cytokines such as IL-10 (p=0.03) and TGF-β (p=0.02), and enhance the expression of homing markers such as CD62L (p=0.005) that are required for in vivo function. TNFɑ-primed Treg had increased ability to proliferate (p=0.02) and, at the same time, to suppress Tcon proliferation (p=0.04) in a mixed lymphocyte reaction against irradiated allogeneic splenocytes, while, on the contrary, TNFɑ-primed Tcon had reduced ability to proliferate in similar conditions in comparison to unprimed Tcon (p=0.0004). To test the effect of TNFɑ priming on in vivo Tcon proliferation we injected TNFɑ-primed and unprimed luc+ Tcon in allogeneic BALB/c Rag2-/- γ-chain-/- immune deficient animals that were sublethally irradiated (400 cGy). BLI at day +7 after Tcon injection revealed reduced TNFɑ-primed Tcon in vivo proliferation (p=0.01) that resulted in milder GvHD symptoms (p=0.02). Finally, in a GvHD prevention mouse model TNFɑ-primed Treg infused at 1:10 Treg/Tcon ratio resulted in improved animal survival as compared to unprimed Treg (p=0.02), demonstrating enhanced efficacy of TNFɑ priming in the in vivo function of Treg. In summary, our study demonstrates that Treg respond to TNFɑ acquiring an activated status resulting in increased function. As TNFɑ is produced by several immune cells during inflammation, our work elucidates aspects of the physiologic mechanisms of Treg function. Furthermore TNFɑ priming of Treg in vitro provides a new tool to optimize Treg cellular therapies also allowing for the use of a reduced cell number for GvHD prevention and treatment. Disclosures No relevant conflicts of interest to declare.

scholarly journals TRPM2 Is Not Required for T-Cell Activation and Differentiation

2022 ◽  
Vol 12 ◽  
Author(s):  
Niels C. Lory ◽  
Mikolaj Nawrocki ◽  
Martina Corazza ◽  
Joanna Schmid ◽  
Valéa Schumacher ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
T Cell Activation ◽  
Cell Activation ◽  
Transient Receptor Potential ◽  
Cell Function ◽  
Intestinal Inflammation ◽  
Activation Markers

Antigen recognition by the T-cell receptor induces a cytosolic Ca2+ signal that is crucial for T-cell function. The Ca2+ channel TRPM2 (transient receptor potential cation channel subfamily M member 2) has been shown to facilitate influx of extracellular Ca2+ through the plasma membrane of T cells. Therefore, it was suggested that TRPM2 is involved in T-cell activation and differentiation. However, these results are largely derived from in vitro studies using T-cell lines and non-physiologic means of TRPM2 activation. Thus, the relevance of TRPM2-mediated Ca2+ signaling in T cells remains unclear. Here, we use TRPM2-deficient mice to investigate the function of TRPM2 in T-cell activation and differentiation. In response to TCR stimulation in vitro, Trpm2-/- and WT CD4+ and CD8+ T cells similarly upregulated the early activation markers NUR77, IRF4, and CD69. We also observed regular proliferation of Trpm2-/- CD8+ T cells and unimpaired differentiation of CD4+ T cells into Th1, Th17, and Treg cells under specific polarizing conditions. In vivo, Trpm2-/- and WT CD8+ T cells showed equal specific responses to Listeria monocytogenes after infection of WT and Trpm2-/- mice and after transfer of WT and Trpm2-/- CD8+ T cells into infected recipients. CD4+ T-cell responses were investigated in the model of anti-CD3 mAb-induced intestinal inflammation, which allows analysis of Th1, Th17, Treg, and Tr1-cell differentiation. Here again, we detected similar responses of WT and Trpm2-/- CD4+ T cells. In conclusion, our results argue against a major function of TRPM2 in T-cell activation and differentiation.

scholarly journals 173 Expression of a membrane-tethered IL-15/IL-15 receptor fusion protein enhances the persistence of MSLN-targeted TRuC-T cells

2021 ◽  
Vol 9 (Suppl 3) ◽  
pp. A185-A185
Author(s):  
Michelle Fleury ◽  
Derrick McCarthy ◽  
Holly Horton ◽  
Courtney Anderson ◽  
Amy Watt ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Fusion Protein ◽  
T Cell Receptor ◽  
Cytokine Production ◽  
Cell Receptor ◽  
Great Promise ◽  
And Function

BackgroundAdoptive cell therapies have shown great promise in hematological malignancies but have yielded little progress in the context of solid tumors. We have developed T cell receptor fusion construct (TRuC®) T cells, which are equipped with an engineered T cell receptor that utilizes the full complement of TCR signaling subunits and recognizes tumor-associated antigens independent of HLA. In clinical trials, mesothelin (MSLN)-targeting TRuC-T cells (TC-210 or gavo-cel) have shown unprecedented results in patients suffering from advanced mesothelioma and ovarian cancer. To potentially increase the depth of response, we evaluated strategies that can promote intra-tumoral T cell persistence and function. Among the common ??-chain cytokines, IL-15 uniquely supports the differentiation and maintenance of memory T cell subsets by limiting terminal differentiation and conferring resistance to IL-2 mediated activation-induced cell death (AICD). In the studies described here, we evaluated the potential of IL-15 as an enhancement to TRuC-T cell phenotype, persistence and function against MSLN+ targets.MethodsPrimary human T cells were activated and transduced with a lentiviral vector encoding an anti-MSLN binder fused to CD3ε alone or co-expressed with a membrane-tethered IL-15rα/IL-15 fusion protein (IL-15fu). Transduced T cells were expanded for 9 days and characterized for expression of the TRuC, IL-15rα and memory phenotype before subjecting them to in vitro functional assays to evaluate cytotoxicity, cytokine production, and persistence. In vivo efficacy was evaluated in MHC class I/II deficient NSG mice bearing human mesothelioma xenografts.ResultsIn vitro, co-expression of the IL-15fu led to similar cytotoxicity and cytokine production as TC-210, but notably enhanced T-cell expansion and persistence upon repeated stimulation with MSLN+ cell lines. Furthermore, the IL-15fu-enhanced TRuC-T cells sustained a significantly higher TCF-1+ population and retained a stem-like phenotype following activation. Moreover, the IL-15fu-enhanced TRuCs demonstrated robust in vivo expansion and intra-tumoral accumulation as measured by ex vivo analysis of TRuC+ cells in the tumor and blood, with a preferential expansion of CD8+ T cells. Finally, IL-15fu-enhanced TRuC-T cells could be observed in the blood long after the tumors were cleared.ConclusionsThese pre-clinical studies suggest that the IL-15fu can synergize with TC-210 to increase the potency and durability of response in patients with MSLN+ tumors.Ethics ApprovalAll animal studies were approved by the respective Institutional Animal Care and Use Committees.

Donor Dual TCR T Cells Preferentially Expand and Mediate Pathologic Alloreactivity in Acute Graft Versus Host Disease

Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 1972-1972
Author(s):  
Gerald P. Morris ◽  
Geoffrey L Uy ◽  
David L Donermeyer ◽  
Paul M Allen ◽  
John F. DiPersio
Keyword(s):  
T Cells ◽  
T Cell ◽  
Graft Versus Host Disease ◽  
Peripheral Blood ◽  
Thymic Selection ◽  
Cell Repertoire ◽  
Host Disease ◽  
Graft Versus Host

Abstract Abstract 1972 The nature of the T cell repertoire mediating pathologic in vivo alloreactivity is an important question for understanding the development of acute graft-versus-host disease (aGvHD) following clinical allogeneic transplantation. We have previously demonstrated that the small proportion of T cells that naturally express 2 T cell receptors (TCR) as a consequence of incomplete TCRa allelic exclusion during thymic development contribute disproportionately to the alloreactive T cell repertoire, both in vitro and in vivo in a mouse model of graft versus host disease (GvHD) (J. Immunol., 182:6639, 2009). Here, we extend these findings to human biology, examining dual TCR T cells from healthy volunteer donors (n = 12) and patients who have undergone allogeneic hematopoietic stem cell transplantation (HSCT) (n = 19). Peripheral blood was collected at day 30 post-HSCT or at the time of presentation with symptomatic acute GvHD. Dual TCR T cells were measured in peripheral blood by pair-wise staining with 3 commercially-available and 2 novel TCRa mAbs. Dual TCR T cells were consistently and significantly expanded in patients with symptomatic aGvHD, representing 5.3±3.8 % of peripheral T cells, compared to 1.7±0.8 % of T cells in healthy controls (p < 0.005) (Figure 1). There was no correlation between dual TCR T cell frequency and GvHD severity. Furthermore, sequential analysis of peripheral blood in 2 patients demonstrated expansion of dual TCR T cells concurrent with the development of aGvHD (Figure 2). Dual TCR T cells from patients with symptomatic aGvHD demonstrated increased expression of CD69 as compared to T cells expressing a single TCR, indicative of preferential activation of dual TCR T cells during aGvHD. Similarly, dual TCR T cells isolated from patients with symptomatic aGvHD demonstrate increased production of IFN-g ex vivo, indicative of the ability to mediate pathogenic alloreactive responses. Dual TCR T cell clones isolated from healthy donors and patients post-HSCT by single cell FACS sorting demonstrate alloreactive responses against a range of allogeneic cell lines in vitro. We propose that the increased alloreactivity of dual TCR T cells results from the less stringent thymic selection for secondary TCR, and thus provides a link between thymic selection, the TCR repertoire, and alloreactivity. These findings may lead to simple ways of phenotypically identifying specific T cells predisposed to inducing aGvHD for subsequent examination of T cell repertoires and functional studies. Furthermore, these data suggest that dual TCR T cells represent a potential predictive biomarker for aGvHD and a potential target for selective T cell depletion in HSCT. Disclosures: No relevant conflicts of interest to declare.

scholarly journals PRMT5 Is Upregulated in Activated T Cells and Is a Novel Therapeutic Target for Acute Gvhd

Blood ◽  
2018 ◽  
Vol 132 (Supplement 1) ◽  
pp. 2034-2034
Author(s):  
Parvathi Ranganathan ◽  
Katiri Snyder ◽  
Nina Zizter ◽  
Hannah K. Choe ◽  
Robert A Baiocchi ◽  
...  
Keyword(s):  
Cell Cycle ◽  
T Cells ◽  
T Cell ◽  
Western Blot ◽  
Cell Function ◽  
T Cell Proliferation ◽  
Activated T Cells ◽  
And Function

Abstract Introduction: Acute graft-versus-host disease (aGVHD), a T cell-mediated immunological disorder is the leading cause of non-relapse mortality in patients receiving allogeneic bone marrow transplants. Protein arginine methyltransferase 5 (PRMT5) catalyzes symmetric dimethylation (me2s) of arginine (R) residues on histones (primarily H3R8 and H3R4) and other proteins. PRMT5 is overexpressed in many leukemias and lymphomas, and epigenetic changes driven by PRMT5 lead to repression of tumor suppressors and promote growth and survival of cancer cells. Recently it was shown that T cells are sensitive to R-methylation and PRMT5 promotes activation of memory T helper cells. Here we investigate: 1) mechanisms by which PRMT5 regulates T cell function; and 2) PRMT5 inhibition as a therapeutic strategy for aGVHD. Materials and Methods: Splenic T cells were isolated from lethally irradiated B6D2F1 mice that received either T cell depleted bone marrow (TCD-BM) or TCD-BM with C57/BL6 (B6) allogeneic splenocytes on day 21 post-transplant. In vitro activation of B6 T cells was achieved with CD3/CD28 Dynabeads or co-culture with allogeneic BM-derived dendritic cells. PRMT5 expression (RT-PCR, western blot) and function (H3R8me2s western blot) were evaluated. PRT220, a novel inhibitor of PRMT5, was used to evaluate PRMT5 inhibition on T cell function in vitro and in vivo. We assessed T cell proliferation (Cell Trace Violet, Ki67), apoptosis (Annexin V), cytokine secretion (ELISA, flow cytometry), cell cycle (PI incorporation), and cell signaling (western blot). Lethally irradiated F1 recipients received TCD-BM only (10x106 cells) or TCD-BM + B6 splenocytes (20 x 106). Recipients of allogeneic splenocytes were treated with PRT220 (2mg/kg) or vehicle by oral gavage once weekly starting day 7 post-transplant. Mice were monitored for survival and clinical aGVHD scores. Results: PRMT5 expression and function is upregulated following T cell activation. Inhibition of PRMT5 reduces T cell proliferation and IFN-g secretion. PRMT5 inhibition in CD3/CD28 stimulated T cells results in disruption of multiple histone epigenetic marks, cell-cycle progression (via G1 arrest) and perturbation of ERK-MAPK signaling cascades. Finally, administration of PRT220 resulted in significantly prolonging the survival of allo-transplanted recipient mice (median survival, PRT220 vs. vehicle, 36.5 vs. 26 days, p=0.01). PRT220-treated recipients also exhibited significant lower aGVHD clinical (p<0.05), pathological scores (p<0.05) and lower serum TNF-a (p<0.05) and IFN-g (p<0.05) than vehicle-treated recipients. Conclusions: PRMT5 expression and function are upregulated in activated T cells. Inhibition of PRMT5 function using a novel and specific small-molecule inhibitor, PRT220, down-regulates T cells proliferative and effector response, induces cell-cycle arrest and perturbs signaling pathways. PRT220 shows potent biological activity in vivo by reducing aGVHD clinical severity and significantly prolonging survival in mouse models of aGVHD. Therefore, PRMT5 is a novel and druggable target for aGVHD. Disclosures No relevant conflicts of interest to declare.

scholarly journals Exhausted CD8+ T cells exhibit low and strongly inhibited TCR signaling during chronic LCMV infection

2020 ◽  
Vol 11 (1) ◽  
Author(s):  
Ioana Sandu ◽  
Dario Cerletti ◽  
Manfred Claassen ◽  
Annette Oxenius
Keyword(s):  
T Cells ◽  
T Cell ◽  
Cell Function ◽  
Viral Infections ◽  
Cell Receptor ◽  
Target Cells ◽  
Tcr Signaling ◽  
And Function

Abstract Chronic viral infections are often associated with impaired CD8+ T cell function, referred to as exhaustion. Although the molecular and cellular circuits involved in CD8+ T cell exhaustion are well defined, with sustained presence of antigen being one important parameter, how much T cell receptor (TCR) signaling is actually ongoing in vivo during established chronic infection is unclear. Here, we characterize the in vivo TCR signaling of virus-specific exhausted CD8+ T cells in a mouse model, leveraging TCR signaling reporter mice in combination with transcriptomics. In vivo signaling in exhausted cells is low, in contrast to their in vitro signaling potential, and despite antigen being abundantly present. Both checkpoint blockade and adoptive transfer of naïve target cells increase TCR signaling, demonstrating that engagement of co-inhibitory receptors curtails CD8+ T cell signaling and function in vivo.

IL15, but Not IL2, Supports Long-Term Survival and Function of Human and Macaque Antigen-Specific CD8+ T Cell Clones.

Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 3237-3237
Author(s):  
Carolina S. Berger ◽  
Michael Jensen ◽  
Stanley R. Riddell
Keyword(s):  
T Cells ◽  
T Cell ◽  
Cd8 T Cell ◽  
Term Survival ◽  
Long Term Survival ◽  
Cd8 T Cell Memory ◽  
And Function

Abstract The adoptive transfer of antigen-specific CD8+ cytotoxic T lymphocyte (CTL) clones that have been isolated and expanded in vitro is a promising treatment modality for both human malignancies and infections. However, establishing immunity of sufficient magnitude and persistence for sustained efficacy is a limitation of this approach. Recent studies have identified a critical role for cytokine signaling including that mediated by IL15 in the establishment and maintenance of CD8+ T cell memory, suggesting that protocols for generating and transferring antigen-specific T cells might be improved. Interleukin-2 (IL2) is the T cell growth factor that has been widely used in vitro and in vivo for promoting T cell proliferation and persistence, but prolonged exposure of T cells to IL2 can enhance susceptibility to cell death and limit CD8+ memory T cell survival. IL15 is a novel cytokine that shares some activities with IL2 such as the induction of T cell proliferation, but exerts contrasting effects on the homeostasis of CD8+ T cell memory in experimental models. Here, we study the utility of IL15 to enhance the long-term survival and function of human and macaque antigen-specific CD8+ CTL clones in vitro. Human and macaque CD8+ CTL clones reactive against CMV were isolated by limiting dilution, expanded over 14 days in the presence of IL2 or IL15 (1–10 ng/ml), and then rested for &gt;4 weeks in media alone and with IL2 or IL15 at 0.01–10 ng/ml. Surviving T cells were enumerated at intervals, monitored for cell surface phenotype, and assayed for cytotoxicity by chromium release assay. CTL expanded in IL2 or IL15 proliferated equivalently over 14 days with a median of 1100 and 1400 fold increase in number, displayed surface markers consistent with an effector memory phenotype (CD45RA−CD62L−CCR7−CD28−), and showed comparable cytotoxicity (n=4). However, exposure after 14 days to IL15 at doses as little as 0.05-0.1 ng/ml greatly enhanced the survival of the CD8+ CTL as determined by Annexin V staining. By contrast, cells cultured without cytokines or with IL2 declined &gt;80% in number over 3 or 11 days, respectively. Of note, IL15 at higher doses (&gt;0.5 ng/ml), but not IL2, efficiently promoted sustained cell growth illustrated by labeling cells with CFSE. Cells cultured with IL15 displayed 1.5-fold increased expression of antiapoptotic molecules such as Bcl-xL and Bcl-2 over those plated in IL2 (n=4), indicating IL15 mediated its effects at least in part by preventing apoptosis. Of note, the cytotoxicity of CTL rested in IL2 was markedly reduced (&gt;60%, n=3), while the presence of IL15 permitted for sustained CTL function and expansion after restimulation. The responses of human and macaque CTL clones to IL15 were equivalent suggesting in vivo studies of T cell transfer in macaques may be predictive of results in humans. We have constructed retroviral vectors encoding intracytoplasmic truncated macaque CD34 or CD19 genes that could serve as nonimmunogenic selectable marker to track macaque T cells after transfer. Macaque T cells were efficiently transduced to express CD34t and CD19t (&gt;50%), and enriched to high purity by immunomagnetic selection. Studies to examine the safety and utility of IL15 on the survival of adoptively transferred CTL in macaques are in progress. Collectively, our data support that novel cytokines such as IL15 may prove useful to augment the long-term survival and effector function of ex vivo expanded antigen-specific CD8+ CTL clones after transfer.

Quantitative and Functional Alterations of the Gamma Delta T-Cell Subset within Follicular Lymphoma Microenvironment.

Blood ◽  
2007 ◽  
Vol 110 (11) ◽  
pp. 2601-2601
Author(s):  
Sophie de Guibert ◽  
Jean-Baptiste Thibert ◽  
Céline Bonnaventure ◽  
Patricia Ame-Thomas ◽  
Céline Pangault ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Follicular Lymphoma ◽  
Peripheral Blood ◽  
Γδ T Cells ◽  
Γδ T Cell ◽  
Ifn Γ ◽  
Nonpeptide Antigens

Abstract T cells carrying a γδ TCR account for less than 5% of CD3pos T cells in healthy individuals but are key effectors of innate immunity through the recognition of some unprocessed nonpeptide antigens of both self and foreign origin. Whereas the Vδ2 subpopulation represents more than 70% of peripheral blood γδ T cells, the Vδ1 subset is mainly located in the mucosal tissue. Increasing evidence suggest that γδ T cells have potent antitumor activity and are implicated in the defense against some haematological and epithelial malignancies. Moreover, Vδ2 T cells constitute an attractive immunotherapy strategy since they could be expanded and activated both in vivo and in vitro using synthetic phosphoantigens and aminobiphosphonates. Such strategies are currently tested in preliminary clinical trials, notably in follicular lymphoma (FL). However, an exhaustive phenotypic and functional characterisation of γδ T cells in this disease, including tumor infiltration, is still lacking. We first explored the composition of FL microenvironment using a multicolour flow cytometry analysis. We observed a significant decrease in the percentage of myeloid (LinnegCD11cposHLADRpos) and plasmacytoid (LinnegCD123posHLADRpos) dendritic cells (P = .0011 and P &lt; .0001, respectively) in FL compared to normal secondary lymphoid organs. In addition, among CD3pos T cells, the proportion of follicular helper T cells (CD4posCXCR5posICOShi) was increased (P = .001) whereas regulatory T-cell (CD4posCD25posfoxp3pos) frequency was not altered. When considering the γδ T-cell compartment, we first highlighted a reduction of the Vδ2 subset in normal tonsils (Vδ2 = 23.48 ± 0.15% of γδ T cells, n = 11) when compared with peripheral blood. Remaining non-δ2 γδT cells were predominantly δ1 T cells. More importantly, infiltrating γδ T cells were significantly decreased in lymph node biopsies from FL patients (mean = 0.48 ± 0.4% of CD3pos T cells; n = 27) when compared both to normal tonsils (mean = 2.49 ± 1.6% of CD3pos T cells; n = 33) (P &lt; .0001) and reactive lymph nodes (mean = 2.64 ± 2.6% of CD3pos T cells; n = 9) (P = .0009). This reduction affected both the Vδ1 and Vδ2 T-cell subsets. The functionality of γδ T cells was then assessed by the measurement of cell expansion and production of IFN-γ upon stimulation with the isopentenyl pyrophosphate (IPP) phosphoantigen. Amplification rate in vitro reached 14.6 ± 4.6 fold in tonsils (n = 10) but only 4.36 ± 1.9 fold in FL samples (n = 7) (P &lt; .002) after 5 days of culture in the presence of IPP + IL-2 + IL-15. When focusing on the δ2 subset, this difference was further increased with a 40-fold amplification in tonsil and a 3-fold amplification in FL samples (P = .0004). Evaluation of IFN-γ production using ELISPOT assay revealed a high heterogeneity among tumor samples since 1 to 40% of δ2 T cells were able to respond to IPP stimulation (n = 7). Preliminary data argued for an association between the quantity and the functionality of γδ T cells in FL tumors. In conclusion, we reported an alteration of γδ T cell frequency and functionality within FL tumor niche. The next purpose will be to correlate these in vitro defects with in vivo clinical responses to immunotherapy strategies targeting γδ T cells.

scholarly journals High-Fat Diet Alters Immunogenic Properties of Circulating and Adipose Tissue-Associated Myeloid-Derived CD45+DDR2+ Cells

2019 ◽  
Vol 2019 ◽  
pp. 1-15
Author(s):  
Sara J. Sidles ◽  
Ying Xiong ◽  
M. Rita I. Young ◽  
Amanda C. LaRue
Keyword(s):  
T Cells ◽  
Adipose Tissue ◽  
T Cell ◽  
Peripheral Blood ◽  
Cell Activity ◽  
Cell Subset ◽  
Total Body Weight ◽  
T Cell Subsets ◽  
Activation Markers

Chronic inflammation is evident in the adipose tissue and periphery of patients with obesity, as well as mouse models of obesity. T cell subsets in obese adipose tissue are skewed towards Th1- and Th17-associated phenotypes and their secreted cytokines contribute to obesity-associated inflammation. Our lab recently identified a novel, myeloid-derived CD45+DDR2+ cell subset that modulates T cell activity. The current study sought to determine how these myeloid-derived CD45+DDR2+ cells are altered in the adipose tissue and peripheral blood of preobese mice and how this population modulates T cell activity. C57BL/6 mice were fed with a diet high in milkfat (60%·kcal, HFD) ad libitum until a 20% increase in total body weight was reached, and myeloid-derived CD45+DDR2+ cells and CD4+ T cells in visceral adipose tissue (VAT), mammary gland-associated adipose tissue (MGAT), and peripheral blood (PB) were phenotypically analyzed. Also analyzed was whether mediators from MGAT-primed myeloid-derived CD45+DDR2+ cells stimulate normal CD4+ T cell cytokine production. A higher percentage of myeloid-derived CD45+DDR2+ cells expressed the activation markers MHC II and CD80 in both VAT and MGAT of preobese mice. CD4+ T cells were preferentially skewed towards Th1- and Th17-associated phenotypes in the adipose tissue and periphery of preobese mice. In vitro, MGAT from HFD-fed mice triggered myeloid-derived CD45+DDR2+ cells to induce CD4+ T cell IFN-γ and TNF-α production. Taken together, this study shows that myeloid-derived CD45+DDR2+ cells express markers of immune activation and suggests that they play an immune modulatory role in the adipose tissue of preobese mice.

scholarly journals Fever supports CD8+ effector T cell responses by promoting mitochondrial translation

2021 ◽  
Vol 118 (25) ◽  
pp. e2023752118
Author(s):  
David O’Sullivan ◽  
Michal A. Stanczak ◽  
Matteo Villa ◽  
Franziska M. Uhl ◽  
Mauro Corrado ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Metabolic Activity ◽  
Cell Metabolism ◽  
Transcriptional Profiling ◽  
Mitochondrial Translation ◽  
In Vivo Models ◽  
And Function

Fever can provide a survival advantage during infection. Metabolic processes are sensitive to environmental conditions, but the effect of fever on T cell metabolism is not well characterized. We show that in activated CD8+ T cells, exposure to febrile temperature (39 °C) augmented metabolic activity and T cell effector functions, despite having a limited effect on proliferation or activation marker expression. Transcriptional profiling revealed an up-regulation of mitochondrial pathways, which was consistent with increased mass and metabolism observed in T cells exposed to 39 °C. Through in vitro and in vivo models, we determined that mitochondrial translation is integral to the enhanced metabolic activity and function of CD8+ T cells exposed to febrile temperature. Transiently exposing donor lymphocytes to 39 °C prior to infusion in a myeloid leukemia mouse model conferred enhanced therapeutic efficacy, raising the possibility that exposure of T cells to febrile temperatures could have clinical potential.

scholarly journals HIV-1 Vpr- and Reverse Transcription-Induced Apoptosis in Resting Peripheral Blood CD4 T Cells and Protection by Common Gamma-Chain Cytokines

2015 ◽  
Vol 90 (2) ◽  
pp. 904-916 ◽  
Author(s):  
Benjamin Trinité ◽  
Chi N. Chan ◽  
Caroline S. Lee ◽  
David N. Levy
Keyword(s):  
T Cells ◽  
Cell Death ◽  
T Cell ◽  
Reverse Transcription ◽  
Peripheral Blood ◽  
Cd4 T Cells ◽  
Productive Infection ◽  
Hiv 1

ABSTRACTHIV-1 infection leads to the progressive depletion of the CD4 T cell compartment by various known and unknown mechanisms.In vivo, HIV-1 infects both activated and resting CD4 T cells, butin vitro, in the absence of any stimuli, resting CD4 T cells from peripheral blood are resistant to infection. This resistance is generally attributed to an intracellular environment that does not efficiently support processes such as reverse transcription (RT), resulting in abortive infection. Here, we show thatin vitroHIV-1 infection of resting CD4 T cells induces substantial cell death, leading to abortive infection.In vivo, however, various microenvironmental stimuli in lymphoid and mucosal tissues provide support for HIV-1 replication. For example, common gamma-chain cytokines (CGCC), such as interleukin-7 (IL-7), render resting CD4 T cells permissible to HIV-1 infection without inducing T cell activation. Here, we find that CGCC primarily allow productive infection by preventing HIV-1 triggering of apoptosis, as evidenced by early release of cytochromecand caspase 3/7 activation. Cell death is triggered both by products of reverse transcription and by virion-borne Vpr protein, and CGCC block both mechanisms. When HIV-1 RT efficiency was enhanced by SIVmac239 Vpx protein, cell death was still observed, indicating that the speed of reverse transcription and the efficiency of its completion contributed little to HIV-1-induced cell death in this system. These results show that a major restriction on HIV-1 infection in resting CD4 T cells resides in the capacity of these cells to survive the early steps of HIV-1 infection.IMPORTANCEA major consequence of HIV-1 infection is the destruction of CD4 T cells. Here, we show that delivery of virion-associated Vpr protein and the process of reverse transcription are each sufficient to trigger apoptosis of resting CD4 T cells isolated from peripheral blood. While these 2 mechanisms have been previously described in various cell types, we show for the first time their concerted effect in inducing resting CD4 T cell depletion. Importantly, we found that cytokines such as IL-7 and IL-4, which are particularly active in sites of HIV-1 replication, protect resting CD4 T cells from these cytopathic effects and, primarily through this protection, rather than through enhancement of specific replicative steps, they promote productive infection. This study provides important new insights for the understanding of the early steps of HIV-1 infection and T cell depletion.

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