Regulatory Dendritic Cells Induced by Bendamustine Are Associated With Enhanced Flt3 Expression and Alloreactive T-Cell Death

The growth factor Flt3 ligand (Flt3L) is central to dendritic cell (DC) homeostasis and development, controlling survival and expansion by binding to Flt3 receptor tyrosine kinase on the surface of DCs. In the context of hematopoietic cell transplantation, Flt3L has been found to suppress graft-versus-host disease (GvHD), specifically via host DCs. We previously reported that the pre-transplant conditioning regimen consisting of bendamustine (BEN) and total body irradiation (TBI) results in significantly reduced GvHD compared to cyclophosphamide (CY)+TBI. Pre-transplant BEN+TBI conditioning was also associated with greater Flt3 expression among host DCs and an accumulation of pre-cDC1s. Here, we demonstrate that exposure to BEN increases Flt3 expression on both murine bone marrow-derived DCs (BMDCs) and human monocyte-derived DCs (moDCs). BEN favors development of murine plasmacytoid DCs, pre-cDC1s, and cDC2s. While humans do not have an identifiable equivalent to murine pre-cDC1s, exposure to BEN resulted in decreased plasmacytoid DCs and increased cDC2s. BEN exposure and heightened Flt3 signaling are associated with a distinct regulatory phenotype, with increased PD-L1 expression and decreased ICOS-L expression. BMDCs exposed to BEN exhibit diminished pro-inflammatory cytokine response to LPS and induce robust proliferation of alloreactive T-cells. These proliferative alloreactive T-cells expressed greater levels of PD-1 and underwent increased programmed cell death as the concentration of BEN exposure increased. Alloreactive CD4+ T-cell death may be attributable to pre-cDC1s and provides a potential mechanism by which BEN+TBI conditioning limits GvHD and yields T-cells tolerant to host antigen.

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Prevention of lethal acute GVHD with an agonistic CD28 antibody and rapamycin

Blood ◽

10.1182/blood-2004-08-3305 ◽

2005 ◽

Vol 105 (3) ◽

pp. 1355-1361 ◽

Cited By ~ 22

Author(s):

Michael H. Albert ◽

Xue-Zhong Yu ◽

Paul J. Martin ◽

Claudio Anasetti

Keyword(s):

T Cells ◽

T Cell ◽

Specific Antibody ◽

Hematopoietic Cell Transplantation ◽

Small Subset ◽

Costimulation Blockade ◽

T Cell Apoptosis ◽

Alloreactive T Cells ◽

Short Course ◽

Cytokine Levels

AbstractSuccessful hematopoietic cell transplantation (HCT) from an allogeneic donor ideally should produce tolerance to recipient alloantigens while preserving anti-infectious and antitumor immunity. Rapamycin together with costimulation blockade can induce tolerance in organ allograft models by inhibiting G1 → S-phase progression and promoting T-cell apoptosis. In contrast to blocking costimulation through CD28, administration of agonistic CD28-specific antibody 37.51 partially prevents lethal graft-versus-host disease (GVHD) by selective depletion of alloreactive T cells in mice. We hypothesized that combining rapamycin with agonistic CD28 treatment would improve GVHD control by tolerizing a small subset of alloreactive T cells that might escape effects of the CD28-specific antibody. A short course of rapamycin plus agonistic CD28 treatment showed synergism at suboptimal doses, was highly effective in preventing lethal GVHD, and was superior to rapamycin plus CD28 blockade in a major histocompatibility complex class I– and II–mismatched HCT model. The combination treatment reduced the number of proliferating, alloreactive cells in the recipient, promoted donor B- and T-cell reconstitution, and reduced inflammatory cytokine levels. Administration of rapamycin plus agonistic CD28 antibodies offers a promising new therapeutic approach to facilitate tolerance after HCT.

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Inflammatory TH1 Cytokines in Target Tissues Promote the Recruitment of Alloreactive T Cells in Graft-Versus-Host Disease.

Blood ◽

10.1182/blood.v114.22.2451.2451 ◽

2009 ◽

Vol 114 (22) ◽

pp. 2451-2451 ◽

Cited By ~ 2

Author(s):

Jeanette Baker ◽

Andreas Beilhack ◽

Lu-en Wai ◽

Stephan Schulz ◽

Carolin Kiesel ◽

...

Keyword(s):

T Cells ◽

T Cell ◽

Inflammatory Cytokines ◽

Graft Versus Host Disease ◽

Acute Gvhd ◽

Conditioning Regimen ◽

Cell Recruitment ◽

Graft Versus Host ◽

Alloreactive T Cells ◽

Effector Phase

Abstract Abstract 2451 Poster Board II-428 Hematopoietic cell transplantation (HCT) is a curative therapy for a variety of malignancies. HCT provides disease eradication through both the high-dose conditioning regimen and an allogeneic graft versus tumor effect (GVT), however graft-versus-host disease (GVHD) remains a major obstacle. In a murine aHCT model of bioluminescence imaging (BLI) we have previously demonstrated that acute GVHD can be separated to a GVHD initiation phase confined to secondary lymphoid organs and a subsequent GVHD effector phase in peripheral target tissues. It has been proposed that host conditioning may not only be crucial in the activation of alloreactive T cells but also determine acute GVHD organ manifestation in the effector phase. Here we wanted to investigate how the host conditioning regimen affects the host target tissues in terms of inflammatory cytokines and their role in donor T cell recruitment. We compared lethally irradiated (8Gy) vs. non-irradiated Balb/c wild type or Balb/c Rag-/-cGC-/- (H-2d) -DKO mice that received allogeneic luciferase+ FVB/N T cells (H-2q). Surprisingly, we did not observe marked differences in the donor T cell proliferation (BLI, CFSE), acquisition of activation markers (CD25, CD44, CD69) and homing receptors (a4b7, aEb7, P-selectin ligand, E-selecting ligand) in conditioned, non-conditioned Balb/c Rag-/-cGC-/-. Despite the upregulation of these homing receptors on donor T cells, infiltration of target tissues (intestinal tract, liver and skin) was significantly accelerated in conditioned and delayed in non-conditioned hosts. As T cell recruitment may have occurred as a result of alterations of the milieu inflammatory cytokines in GVHD target tissues, we compared the cytokine profile in conditioned vs. non-conditioned recipients. At days 3 and 6 after transplantation tissues were harvested and cytokines from the target tissues; liver, large bowel, small bowel, peripheral blood and a non target tissue: kidney were analyzed for a TH1/TH2/Th17a cytokines. At day 3 high levels of INF-γ and TNF were detected in the Balb/c WT conditioned host compared to the non-conditioned host in all target tissues (SB, LB, and liver) and most markedly in peripheral blood and the large bowel. More importantly the Balb/c Rag-/-cGC-/- conditioned host displayed about 5 times higher levels of both inflammatory cytokines compared to the non conditioned DKO hosts and to the Balb/c WT. Similar results with a lesser levels were observed both for IL-2 and IL17a. By day 6 similar results are seen but with a much reduced expression of the cytokines, indicating that the cytokine storm peak was maybe at day 3. In summary host conditioning is not a requirement for alloreactive T cell activation rather induced inflammatory cytokines such as TNF and INF-γ are the determinant factors for effector T cell recruitment to GVHD target tissues. JB and AB contributed equally to this work. Disclosures: No relevant conflicts of interest to declare.

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Infection of Human Monocyte-Derived Macrophages with Chlamydia trachomatis Induces Apoptosis of T Cells: a Potential Mechanism for Persistent Infection

Infection and Immunity ◽

10.1128/iai.68.12.6704-6711.2000 ◽

2000 ◽

Vol 68 (12) ◽

pp. 6704-6711 ◽

Cited By ~ 39

Author(s):

Michael C. Jendro ◽

Tobias Deutsch ◽

Britta Körber ◽

Lars Köhler ◽

Jens G. Kuipers ◽

...

Keyword(s):

T Cells ◽

Cell Death ◽

T Cell ◽

Chlamydia Trachomatis ◽

Cell Apoptosis ◽

Chlamydial Infection ◽

Human Monocyte ◽

T Cell Response ◽

T Cell Apoptosis ◽

Frequent Event

ABSTRACT Viruses can escape T-cell surveillance by infecting macrophages and thereby induce apoptosis of noninfected T cells. This ability had not been demonstrated for bacteria. We investigated whether infection of macrophages with the important human pathogen Chlamydia trachomatis can induce T-cell apoptosis. BecauseChlamydia-Mycoplasma coinfection is a frequent event, the ability of Mycoplasma fermentans-infected macrophages to induce T-cell apoptosis was also studied. Infected macrophages were cocultivated with autologous T cells in different activation states. Propidium iodide-based fluorescence-activated cell sorter analysis demonstrated that macrophages infected with viable chlamydiae induced T-cell death. Apoptosis was identified as the mode of death induction by using a terminal deoxynucleotidyltransferase-mediated dUTP-biotin nick end labeling assay. Induction of T-cell death was macrophage dependent. Incubation of T cells with infectious chlamydiae in the absence of macrophages did not lead to T-cell apoptosis. UV irradiation of chlamydiae diminished the ability to induce death. T-cell death was induced by a cell-free supernatant of infected macrophages. Not only phytohemagglutinin-preactivated T cells but also non-mitogen-preactivated T cells were susceptible to C. trachomatis-induced apoptosis. In contrast, M. fermentans infection of macrophages did not induce T-cell death. Coinfection had no additional effect. In summary, intracellular chlamydial infection of macrophages can induce T-cell apoptosis. Apoptosis induction by chlamydiae possibly explains how persistently infected macrophages escape T-cell surveillance and why theChlamydia-specific T-cell response is diminished during persistent chlamydial infection.

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Immunogenomic Gene Signature of Cell-Death Associated Genes with Prognostic Implications in Lung Cancer

Cancers ◽

10.3390/cancers13010155 ◽

2021 ◽

Vol 13 (1) ◽

pp. 155

Author(s):

Pankaj Ahluwalia ◽

Meenakshi Ahluwalia ◽

Ashis K. Mondal ◽

Nikhil Sahajpal ◽

Vamsi Kota ◽

...

Keyword(s):

Lung Cancer ◽

T Cells ◽

Cell Death ◽

T Cell ◽

High Risk ◽

Lung Adenocarcinoma ◽

Risk Group ◽

High Risk Group ◽

Free Survival ◽

Cell Death Pathways

Lung cancer is one of the leading causes of death worldwide. Cell death pathways such as autophagy, apoptosis, and necrosis can provide useful clinical and immunological insights that can assist in the design of personalized therapeutics. In this study, variations in the expression of genes involved in cell death pathways and resulting infiltration of immune cells were explored in lung adenocarcinoma (The Cancer Genome Atlas: TCGA, lung adenocarcinoma (LUAD), 510 patients). Firstly, genes involved in autophagy (n = 34 genes), apoptosis (n = 66 genes), and necrosis (n = 32 genes) were analyzed to assess the prognostic significance in lung cancer. The significant genes were used to develop the cell death index (CDI) of 21 genes which clustered patients based on high risk (high CDI) and low risk (low CDI). The survival analysis using the Kaplan–Meier curve differentiated patients based on overall survival (40.4 months vs. 76.2 months), progression-free survival (26.2 months vs. 48.6 months), and disease-free survival (62.2 months vs. 158.2 months) (Log-rank test, p < 0.01). Cox proportional hazard model significantly associated patients in high CDI group with a higher risk of mortality (Hazard Ratio: H.R 1.75, 95% CI: 1.28–2.45, p < 0.001). Differential gene expression analysis using principal component analysis (PCA) identified genes with the highest fold change forming distinct clusters. To analyze the immune parameters in two risk groups, cytokines expression (n = 265 genes) analysis revealed the highest association of IL-15RA and IL 15 (> 1.5-fold, p < 0.01) with the high-risk group. The microenvironment cell-population (MCP)-counter algorithm identified the higher infiltration of CD8+ T cells, macrophages, and lower infiltration of neutrophils with the high-risk group. Interestingly, this group also showed a higher expression of immune checkpoint molecules CD-274 (PD-L1), CTLA-4, and T cell exhaustion genes (HAVCR2, TIGIT, LAG3, PDCD1, CXCL13, and LYN) (p < 0.01). Furthermore, functional enrichment analysis identified significant perturbations in immune pathways in the higher risk group. This study highlights the presence of an immunocompromised microenvironment indicated by the higher infiltration of cytotoxic T cells along with the presence of checkpoint molecules and T cell exhaustion genes. These patients at higher risk might be more suitable to benefit from PD-L1 blockade or other checkpoint blockade immunotherapies.

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Type I interferons affect the metabolic fitness of CD8+ T cells from patients with systemic lupus erythematosus

Nature Communications ◽

10.1038/s41467-021-22312-y ◽

2021 ◽

Vol 12 (1) ◽

Cited By ~ 1

Author(s):

Norzawani Buang ◽

Lunnathaya Tapeng ◽

Victor Gray ◽

Alessandro Sardini ◽

Chad Whilding ◽

...

Keyword(s):

Systemic Lupus Erythematosus ◽

T Cells ◽

Cell Death ◽

T Cell ◽

Lupus Erythematosus ◽

Type I Interferons ◽

Type I ◽

Type I Ifn ◽

Systemic Lupus ◽

Mitochondrial Abnormalities

AbstractThe majority of patients with systemic lupus erythematosus (SLE) have high expression of type I IFN-stimulated genes. Mitochondrial abnormalities have also been reported, but the contribution of type I IFN exposure to these changes is unknown. Here, we show downregulation of mitochondria-derived genes and mitochondria-associated metabolic pathways in IFN-High patients from transcriptomic analysis of CD4+ and CD8+ T cells. CD8+ T cells from these patients have enlarged mitochondria and lower spare respiratory capacity associated with increased cell death upon rechallenge with TCR stimulation. These mitochondrial abnormalities can be phenocopied by exposing CD8+ T cells from healthy volunteers to type I IFN and TCR stimulation. Mechanistically these ‘SLE-like’ conditions increase CD8+ T cell NAD+ consumption resulting in impaired mitochondrial respiration and reduced cell viability, both of which can be rectified by NAD+ supplementation. Our data suggest that type I IFN exposure contributes to SLE pathogenesis by promoting CD8+ T cell death via metabolic rewiring.

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Susceptibility to cell death is a dominant phenotype: triggering of activation-driven T-cell death independent of the T-cell antigen receptor complex

Molecular and Cellular Biology ◽

10.1128/mcb.12.1.379-385.1992 ◽

1992 ◽

Vol 12 (1) ◽

pp. 379-385

Author(s):

G Nickas ◽

J Meyers ◽

L D Hebshi ◽

J D Ashwell ◽

D P Gold ◽

...

Keyword(s):

T Cells ◽

Cell Death ◽

T Cell ◽

Interleukin 2 ◽

Antigen Receptor ◽

Alternative Activation ◽

Receptor Complex ◽

T Cell Antigen Receptor ◽

Cell Antigen Receptor ◽

Cell Antigen

The failure of Thy-1 and Ly-6 to trigger interleukin-2 production in the absence of surface T-cell antigen receptor complex (TCR) expression has been interpreted to suggest that functional signalling via these phosphatidylinositol-linked alternative activation molecules is dependent on the TCR. We find, in contrast, that stimulation of T cells via Thy-1 or Ly-6 in the absence of TCR expression does trigger a biological response, the cell suicide process of activation-driven cell death. Activation-driven cell death is a process of physiological cell death that likely represents the mechanism of negative selection of T cells. The absence of the TCR further reveals that signalling leading to activation-driven cell death and to lymphokine production are distinct and dissociable. In turn, the ability of alternative activation molecules to function in the absence of the TCR raises another issue: why immature T cells, thymomas, and hybrids fail to undergo activation-driven cell death in response to stimulation via Thy-1 and Ly-6. One possibility is that these activation molecules on immature T cells are defective. Alternatively, susceptibility to activation-driven cell death may be developmentally regulated by TCR-independent factors. We have explored these possibilities with somatic cell hybrids between mature and immature T cells, in which Thy-1 and Ly-6 are contributed exclusively by the immature partner. The hybrid cells exhibit sensitivity to activation-driven cell death triggered via Thy-1 and Ly-6. Thus, the Thy-1 and Ly-6 molecules of the immature T cells can function in a permissive environment. Moreover, with regard to susceptibility to Thy-1 and Ly-6 molecules of the immature T cells can function in a permissive environment. Moreover, with regard to susceptibility to Thy-1 and Ly-6 triggering, the mature phenotype of sensitivity to cell death is genetically dominant.

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Combination cancer immunotherapy targeting PD-1 and GITR can rescue CD8+T cell dysfunction and maintain memory phenotype

Science Immunology ◽

10.1126/sciimmunol.aat7061 ◽

2018 ◽

Vol 3 (29) ◽

pp. eaat7061 ◽

Cited By ~ 44

Author(s):

Bei Wang ◽

Wen Zhang ◽

Vladimir Jankovic ◽

Jacquelynn Golubov ◽

Patrick Poon ◽

...

Keyword(s):

T Cells ◽

Cell Death ◽

T Cell ◽

Programmed Cell Death ◽

Cancer Immunotherapy ◽

Effector Memory ◽

Cell Phenotype ◽

Checkpoint Inhibition ◽

Cell Dysfunction ◽

T Cell Dysfunction

Most patients with cancer do not develop durable antitumor responses after programmed cell death protein 1 (PD-1) or programmed cell death ligand 1(PD-L1) checkpoint inhibition monotherapy because of an ephemeral reversal of T cell dysfunction and failure to promote long-lasting immunological T cell memory. Activating costimulatory pathways to induce stronger T cell activation may improve the efficacy of checkpoint inhibition and lead to durable antitumor responses. We performed single-cell RNA sequencing of more than 2000 tumor-infiltrating CD8+T cells in mice receiving both PD-1 and GITR (glucocorticoid-induced tumor necrosis factor receptor–related protein) antibodies and found that this combination synergistically enhanced the effector function of expanded CD8+T cells by restoring the balance of key homeostatic regulators CD226 and T cell immunoreceptor with Ig and ITIM domains (TIGIT), leading to a robust survival benefit. Combination therapy decreased CD8+T cell dysfunction and induced a highly proliferative precursor effector memory T cell phenotype in a CD226-dependent manner. PD-1 inhibition rescued CD226 activity by preventing PD-1–Src homology region 2 (SHP2) dephosphophorylation of the CD226 intracellular domain, whereas GITR agonism decreased TIGIT expression. Unmasking the molecular pathways driving durable antitumor responses will be essential to the development of rational approaches to optimizing cancer immunotherapy.

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The Role of Peptides in T Cell Alloreactivity Is Determined by Self–Major Histocompatibility Complex Molecules

Journal of Experimental Medicine ◽

10.1084/jem.191.5.805 ◽

2000 ◽

Vol 191 (5) ◽

pp. 805-812 ◽

Cited By ~ 62

Author(s):

Reinhard Obst ◽

Nikolai Netuschil ◽

Karsten Klopfer ◽

Stefan Stevanović ◽

Hans-Georg Rammensee

Keyword(s):

T Cells ◽

Major Histocompatibility Complex ◽

T Cell ◽

Target Cells ◽

Major Histocompatibility ◽

Complex Molecules ◽

Mhc Molecules ◽

Histocompatibility Complex ◽

Alloreactive T Cells

By analyzing T cell responses against foreign major histocompatibility complex (MHC) molecules loaded with peptide libraries and defined self- and viral peptides, we demonstrate a profound influence of self-MHC molecules on the repertoire of alloreactive T cells: the closer the foreign MHC molecule is related to the T cell's MHC, the higher is the proportion of peptide-specific, alloreactive (“allorestricted”) T cells versus T cells recognizing the foreign MHC molecule without regard to the peptide in the groove. Thus, the peptide repertoire of alloreactive T cells must be influenced by self-MHC molecules during positive or negative thymic selection or peripheral survival, much like the repertoire of the self-restricted T cells. In consequence, allorestricted, peptide-specific T cells (that are of interest for clinical applications) are easier to obtain if T cells and target cells express related MHC molecules.

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Selective Depletion of Alloreactive T Cells and Study of Anti-Tumor Activity of Specific T Cell Clones in Patients with Leukemia and Renal Carcinoma

Clinical Immunology ◽

10.1016/j.clim.2007.03.482 ◽

2007 ◽

Vol 123 ◽

pp. S106-S107

Author(s):

Eva Matejkova ◽

Zuzana Hrotekova ◽

Drahomira Kyjovska ◽

Jaroslav Michalek ◽

Petra Vidlakova

Keyword(s):

T Cells ◽

T Cell ◽

Renal Carcinoma ◽

T Cell Clones ◽

Alloreactive T Cells ◽

Cell Clones ◽

Selective Depletion ◽

Anti Tumor Activity

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Fas ligand mediates activation-induced cell death in human T lymphocytes.

Journal of Experimental Medicine ◽

10.1084/jem.181.1.71 ◽

1995 ◽

Vol 181 (1) ◽

pp. 71-77 ◽

Cited By ~ 625

Author(s):

M R Alderson ◽

T W Tough ◽

T Davis-Smith ◽

S Braddy ◽

B Falk ◽

...

Keyword(s):

T Cells ◽

Cell Death ◽

T Cell ◽

Fas Ligand ◽

Significant Proportion ◽

Cell Receptor ◽

Target Cells ◽

Activated T Cells ◽

Activation Induced Cell Death ◽

Fas L

A significant proportion of previously activated human T cells undergo apoptosis when triggered through the CD3/T cell receptor complex, a process termed activation-induced cell death (AICD). Ligation of Fas on activated T cells by either Fas antibodies or recombinant human Fas-ligand (Fas-L) also results in cytolysis. We demonstrate that these two pathways of apoptosis are causally related. Stimulation of previously activated T cells resulted in the expression of Fas-L mRNA and lysis of Fas-positive target cells. Fas-L antagonists inhibited AICD of T cell clones and staphylococcus enterotoxin B (SEB)-specific T cell lines. The data indicate AICD in previously stimulated T cells is mediated by Fas/Fas-L interactions.

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