FRI0010 GM-CSFR PATHWAY IS IMPLICATED IN PATHOGENIC INFLAMMATORY MECHANISMS IN GIANT CELL ARTERITIS

2020 ◽  
Vol 79 (Suppl 1) ◽  
pp. 576.1-576
Author(s):  
M. C. Cid ◽  
S. Muralidharan ◽  
M. Corbera-Bellalta ◽  
G. Espigol-Frigole ◽  
J. Marco Hernandez ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Mrna Expression ◽  
Giant Cell Arteritis ◽  
Giant Cell ◽  
Signaling Pathway ◽  
Ex Vivo ◽  
Cell Marker ◽  
Gm Csf ◽  
Inflammatory Macrophages

Background:Giant Cell Arteritis (GCA) is characterized by inflammation of large and medium arteries. Classic symptoms include headaches, malaise and, in severe cases, blindness and aortic aneurysms. Corticosteroids (CS) are the first line of treatment. Relapsing disease patients undergo multiple courses of CS therapy increasing their CS exposure and toxicity. A significant unmet need for disease-modifying CS-sparing therapy remains in GCA as the efficacy of current treatment options, including tocilizumab have limitations.We have previously reported elevated expression of granulocyte-macrophage colony stimulating factor (GM-CSF) pathway transcriptomic signature in GCA vessels. GM-CSF may contribute to underlying disease mechanisms by regulating inflammatory macrophages, dendritic cells (DCs) and T helper (TH1/TH17) cells which are involved in GCA pathogenesis. GM-CSF produced by T cells1can promote polarization of inflammatory macrophages2and recruitment and differentiation of monocytes into inflammatory DCs2that can in turn recruit T cells and stimulate TH1/TH17 differentiation creating a feedback loop. GM-CSF may also exert direct effects on angiogenesis3and vessel wall remodeling4.Objectives:To demonstrate the contributing role of GM-CSF pathway to inflammation in GCA arteries.Methods:Immunostaining was used to examine expression of GM-CSF and GM-CSF-Rα proteins in temporal artery biopsies (TABs) from GCA and controls (patients with suspected but not confirmed GCA and a negative TAB). Costaining with cell markers such as CD31, CD3, and CD68 allowed visualization of cells expressing GM-CSF and GM-CSF-Rα. Expression of GM-CSF pathway molecules such as phospho-JAK2 and PU.1 proteins was detected by immunohistochemical staining of GCA and control TABs.Ex vivocultured GCA arteries treated (10 each) with mavrilimumab (anti-GM-CSF-Rα) or placebo for 5 days were assayed for gene expression by qPCR, and culture supernatants were analyzed by ELISA.Results:Endothelial cells and macrophages were the main cell types expressing GM-CSF and GM-CSF-Rα. Increased expression of phospho-JAK2 (activated signaling molecule) and nuclear-localized PU.1 (transcription factor) in GCA TABs compared to controls indicated the presence of active GM-CSF signaling pathway in GCA.Inhibition of PU.1 mRNA expression inex vivocultures of GCA arteries treated with mavrilimumab indicated blockade of GM-CSFR signaling pathway. Mavrilimumab induced decrease in mRNA expression of key cell type markers including DC and macrophage activation markers CD83 and HLA-DRA, monocyte markers CD14 and CD16, T cell marker CD3ε, and B cell marker CD20 in these GCA artery cultures. Expression of inflammatory TH1/TH17 factors IFNγ (mRNA), TNFα, CXCL10 (IFNγ-stimulated chemokine) and IL-6 (mRNA and protein) was also inhibited by mavrilimumab in GCA artery cultures.Conclusion:Increased GM-CSF, GM-CSF-Rα, and downstream pathway-associated protein levels in GCA biopsies were consistent with previously-observed increased transcriptome signature. Expression of genes associated with inflammatory cells was suppressed by mavrilimumab in cultured GCA arteries. These data implicate the GM-CSF pathway in GCA pathophysiology and increase confidence in rationale for targeting the GM-CSF pathway in GCA.References:[1]GM-CSF and T-cell responses: what we do and don’t know. Shiet al., Cell Res 2006[2]GM-CSF-Dependent Inflammatory Pathways. Hamilton, Front Immunol 2019[3]GM-CSF increases tumor growth and angiogenesis. Zhenget al., Tumour Biol 2017[4]GM-CSF deficiency affects vascular elastin production and integrity of elastic lamellae. Weissen-Plenzet al., J Vasc Res 2008Disclosure of Interests:Maria C. Cid Grant/research support from: Kiniksa Pharmaceuticals, Consultant of: Janssen, Abbvie, Roche, GSK, Speakers bureau: Vifor, Sujatha Muralidharan Shareholder of: Kiniksa, Employee of: Kiniksa, Marc Corbera-Bellalta: None declared, Georgina Espigol-Frigole Consultant of: Roche and Janssen, Javier Marco Hernandez: None declared, Amanda Denuc: None declared, Roberto Rios-Garces: None declared, Nekane Terrades-Garcia: None declared, John F. Paolini Shareholder of: Kiniksa, Employee of: Kiniksa, Annalisa D’Andrea Shareholder of: Kiniksa, Employee of: Kiniksa

scholarly journals Distinct vascular lesions in giant cell arteritis share identical T cell clonotypes.

1994 ◽  
Vol 179 (3) ◽  
pp. 951-960 ◽  
Author(s):  
C M Weyand ◽  
J Schönberger ◽  
U Oppitz ◽  
N N Hunder ◽  
K C Hicok ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Giant Cell Arteritis ◽  
Giant Cell ◽  
Gene Segment ◽  
Interleukin 2 ◽  
Granulomatous Inflammation ◽  
Temporal Artery ◽  
Cell Receptor ◽  
Vascular Lesions

Giant cell arteritis (GCA) is a spontaneous vasculitic syndrome that specifically targets the walls of medium and large arteries. Vascular lesions are characterized by patchy granulomatous infiltrates composed of T cells, macrophages, histiocytes, and giant cells. To test the hypothesis that a locally residing antigen recruits T cells into the vessel walls, we have analyzed T cell receptor (TCR) molecules of tissue infiltrating T cells. A total of 638 CD4+ T cell clones were isolated from temporal artery specimens of three patients with GCA. Analysis of TCR molecules for the usage of V beta 1-V beta 20 revealed that all TCR V beta elements were represented, demonstrating that interleukin 2 (IL-2)-responsive T cells infiltrating the tissue are highly diverse. To detect expanded T cell specificities, we made use of the patchy character of the inflammatory disease and compared the TCR repertoire of T cells established from independent vasculitic foci of the same artery. Sequence analysis of TCR V beta chains documented that individual TCR specificities were present in multiple copies, indicating clonal expansion. T cells with identical beta chains were isolated from distinct inflammatory foci of the same patient. These specificities represented only a small fraction of tissue-infiltrating T cells and involved the V beta 5.3 gene segment in the two patients sharing the HLA-DRB1*0401 allele. The third complementarity determining region of clonally expanded TCR beta chains was characterized by a cluster of negatively and positively charged residues, suggesting that the juxtaposed antigenic peptide is charged. The sharing of identical T cell specificities by distinct and independent regions of the granulomatous inflammation suggests that these T cells are disease relevant and that their repertoire is strongly restricted. These data suggest that an antigen residing in the arterial wall is recognized by a small fraction of CD4+ T cells in the inflammatory process characteristic for GCA.

scholarly journals Activation of Arterial Wall Dendritic Cells and Breakdown of Self-tolerance in Giant Cell Arteritis

2004 ◽  
Vol 199 (2) ◽  
pp. 173-183 ◽  
Author(s):  
Wei Ma-Krupa ◽  
Myung-Shin Jeon ◽  
Silvia Spoerl ◽  
Thomas F. Tedder ◽  
Jörg J. Goronzy ◽  
...  
Keyword(s):  
T Cells ◽  
Dendritic Cells ◽  
T Cell ◽  
Giant Cell Arteritis ◽  
Giant Cell ◽  
Scid Mouse ◽  
Severe Combined Immunodeficiency ◽  
Medium Size ◽  
Early Event ◽  
Mouse Chimeras

Giant cell arteritis (GCA) is a granulomatous and occlusive vasculitis that causes blindness, stroke, and aortic aneurysm. CD4+ T cells are selectively activated in the adventitia of affected arteries. In human GCA artery–severe combined immunodeficiency (SCID) mouse chimeras, depletion of CD83+ dendritic cells (DCs) abrogated vasculitis, suggesting that DCs are critical antigen-presenting cells in GCA. Healthy medium-size arteries possessed an indigenous population of DCs at the adventitia–media border. Adoptive T cell transfer into temporal artery–SCID mouse chimeras demonstrated that DCs in healthy arteries were functionally immature, but gained T cell stimulatory capacity after injection of lipopolysaccharide. In patients with polymyalgia rheumatica (PMR), a subclinical variant of GCA, adventitial DCs were mature and produced the chemokines CCL19 and CCL21, but vasculitic infiltrates were lacking. Human histocompatibility leukocyte antigen class II–matched healthy arteries, PMR arteries, and GCA arteries were coimplanted into SCID mice. Immature DCs in healthy arteries failed to stimulate T cells, but DCs in PMR arteries could attract, retain, and activate T cells that originated from the GCA lesions. We propose that in situ maturation of DCs in the adventitia is an early event in the pathogenesis of GCA. Activation of adventitial DCs initiates and maintains T cell responses in the artery and breaks tissue tolerance in the perivascular space.

Quality of Leukemia-Derived Dendritic Cells (DC) and T-Cells Are Predictive for the Specific Anti-Leukemic Potential of DC-Trained T-Cells.

Blood ◽  
2007 ◽  
Vol 110 (11) ◽  
pp. 4883-4883
Author(s):  
Helga Schmetzer ◽  
Christine Grabrucker ◽  
Anja Liepert ◽  
Andreas Kremser ◽  
Julia Loibl ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Clinical Response ◽  
Memory T Cells ◽  
Ex Vivo ◽  
Cell Activity ◽  
Lytic Activity ◽  
Gm Csf

Abstract The presentation of leukemic antigens can be improved by in vitro conversion of leukemic cells in leukemia-derived DC (DCleu), thereby forming a platform for the generation of leukemia-specific cytotoxic lymphocytes (CTL). DC/ DCleu can be quantified by combination of suitable blast and DC-antigens (Schmetzer 2007). Now we want to enlight the role of the quality of DC/ DCleu and (DC-trained) T-cells to mediate leukemia-cytotoxic reactions ex vivo or to predict or correlate the clinical response to a DC/DLI-based immunotherapy in vivo. Methods: DC were generated with the best of 3 DC-generating methods(‘MCM-mimic’, Lee 2003;’Ca-Ionophore’, Houtenbos 2003; ‘Picibanil’, Sato 2003; Kufner S. 2005 I-III) and used to train T-cells in a ‘Mixed lymphocyte culture’ (MLC) for 10 days in the presence of IL-2 and restimulated with patient-derived DC every 3 days. Co-expression of T-cell-antigens on T-cells was measured before and after MLC. The antileukemic cytotoxic activity of DC-trained (or blast trained or untrained) T-cells against naïve blasts was quantified. We could show, that DC can be generated in every case of AML. In 65% of the cases T-cells gained a leukaemia-lytic activity after 24h training with DC, in 35% an increase of blasts was seen. The T-cell training efficacy with DC was superior to a blast training given rise to specific leukaemia-cytotoxic cells. A comparison of cases with a gain of lytic T-cell activity (n=11)with those without a lytic activity (n=6) showed 78 vs 51% DCleu, 55 vs 34% mature and 32 vs 18% migratory DC and 50vs40% proliferating T-cells, 53 vs 46% memory T-cells, 68vs56% CD4 and 38 vs 60% CD8 pos T-cells. Moreover we could evaluate cut-off values: 90% of DC-trained T-cells could gain a lytic activity if > 65% DCleu were in the MLR. In AML-patients who had presented with a relapse after SCT we could demonstrate a better ex vivo convertibility of blasts to DCleu if patients had successfully responded to a GM-CSF/DLI-based therapy of their relapse after SCT compared to cases with no response (72 vs 36% blasts convertible to DCleu; 44 vs 29% generable DC). Summary: The generation of DC/DCleu is possible in every AML/MDS-patient. Ex vivo convertibility of blasts to DCleu could predict a clinical response to a GM-CSF/DLI-based therapy or indirectly prove, that GM-CSF in vivo could contribute to produce DC/DCleu in vivo. A successful DC-training of T-cells is associated with high matureDC/ DCleu counts and high rates of proliferating, CD4 and Memory-T-cells. The lytic activity of DC-trained T-cells is predictable by quantities of DCleu generable in individual cases. So the generability of DC/DCleu and of DC/MNC-trained T-cells could contribute to predict the clinical course of the disease and could help to create specific anti-leukemic T-cells for immunotherapy of AML.

scholarly journals Immunogenicity of Personalized Dendritic-cell Therapy in HIV-1 Infected Individuals Under Suppressive Antiretroviral Treatment: Interim Analysis From a Phase II Clinical Trial.

2021 ◽  
Author(s):  
Marcela Vassão de Almeida Batista ◽  
Laís Teodoro Silva ◽  
Sadia Samer ◽  
Telma Miyuki Oshiro ◽  
Iart Luca Shytaj ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Antiretroviral Treatment ◽  
Ex Vivo ◽  
Gm Csf ◽  
T Cell Immune Responses ◽  
Ifn Γ ◽  
Dendritic Cell Therapy ◽  
Hiv 1

Abstract BackgroundWe developed a personalized Monocyte-Derived Dendritic Therapy (MDDCT) for HIV-infected individuals on suppressive antiretroviral treatment and evaluated HIV-specific T-cell responses.MethodsPBMCs were obtained from 10 HIV+ individuals enrolled in trial NCT02961829. Monocytes were differentiated into DCs using IFN-α and GM-CSF. After sequencing each patient’s HIV-1 Gag and determining HLA profiles, autologous Gag peptides were selected based on the predicted individual immunogenicity and used to pulse MDDCs. Three doses of the MDDCT were administered every 15 days. To assess immunogenicity, patients’ cells were stimulated in vitro with autologous peptides, and intracellular IL-2, TNF, and interferon-gamma (IFN-γ) production were measured in CD4+ and CD8+ T-cells. ResultsThe protocol of ex-vivo treatment with IFN-α and GM-CSF was able to induce maturation of MDDCs, as well as to preserve their viability for reinfusion. MDDCT administration was associated with increased expression of IL-2 in CD4+ and CD8+ T-cells at 15 and/or 30 days after the first MDDCT administration. Moreover, intracellular TNF and IFN-γ expression was significantly increased in CD4+ T-cells. The number of candidates that increased in vitro the cytokine levels in CD4+ and CD8+ T cells upon stimulation with Gag peptides from baseline to days 15 and from baseline to days 30 and days 120 after MDDCT was significant as compared to Gag unstimulated response. This was accompanied by an increasing trend in the frequency of polyfunctional T-cells over time, which was visible when considering both cells expressing two and three out of the three cytokines examined. ConclusionsMDDC has a mature profile, and this MDDCT promoted in-vitro T-cell immune responses in HIV-infected patients undergoing long-term suppressive antiretroviral treatment.NCT02961829: (Multi Interventional Study Exploring HIV-1 Residual Replication: a Step Towards HIV-1 Eradication and Sterilizing Cure, https://www.clinicaltrials.gov/ct2/show/NCT02961829, posted November 11th, 2016).

scholarly journals Restoring regulatory T-cell dysfunction in Alzheimer’s disease through ex vivo expansion

2020 ◽  
Vol 2 (2) ◽  
Author(s):  
Alireza Faridar ◽  
Aaron D Thome ◽  
Weihua Zhao ◽  
Jason R Thonhoff ◽  
David R Beers ◽  
...  
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
T Cells ◽  
T Cell ◽  
Regulatory T Cells ◽  
Regulatory T Cell ◽  
Ex Vivo ◽  
Ex Vivo Expansion ◽  
T Cell Proliferation ◽  
Inflammatory Macrophages

Abstract Inflammation is a significant component of Alzheimer’s disease pathology. While neuroprotective microglia are important for containment/clearance of Amyloid plaques and maintaining neuronal survival, Alzheimer inflammatory microglia may play a detrimental role by eliciting tau pathogenesis and accelerating neurotoxicity. Regulatory T cells have been shown to suppress microglia-mediated inflammation. However, the role of regulatory T cells in ameliorating the proinflammatory immune response in Alzheimer’s disease requires further investigation. Forty-six patients with Alzheimer disease, 42 with mild cognitive impairment and 41 healthy controls were studied. The phenotypes of peripheral regulatory T cells were assessed with multicolour flow cytometry. Regulatory T cells were co-cultured with responder T cells and proliferation was determined by 3H-thymidine incorporation. In separate experiments, regulatory T cells were added to induced pluripotent stem cell-derived pro-inflammatory macrophages and changes in interleukin-6/tumour necrosis-alpha transcripts and protein levels were measured. Freshly isolated regulatory T cells were expanded ex vivo in the presence of CD3/CD28 expander beads, interleukin-2 and rapamycin to promote their suppressive function. We found that the suppressive function of regulatory T cells on responder T-cell proliferation was compromised at the Alzheimer disease stage, compared with mild cognitive impairment and healthy controls. CD25 mean fluorescence intensity in regulatory T-cell population was also reduced in Alzheimer dementia patients. Regulatory T cells did not suppress pro-inflammatory macrophages at baseline. Following ex vivo expansion, regulatory T-cell suppression of responder T-cell proliferation and pro-inflammatory macrophage activation increased in both patients and controls. Expanded regulatory T cells exerted their immunoregulatory function on pro-inflammatory macrophages through a contact-mediated mechanism. In conclusion, regulatory T-cell immunophenotype and function are compromised in Alzheimer’s disease. Following ex vivo expansion, the immunomodulatory function of regulatory T cells is enhanced even at advanced stages of Alzheimer’s disease. Restoration of regulatory T-cell function could be explored as a means to modulate the inflammatory status of Alzheimer’s disease.

A Step towards Reconstitution or Maintenance of Remission before or after Stem Cell Transplantation in AML/MDS by Ex Vivo Generation of Leukaemia-Derived DC (DCleu) and DC-Activated T-Cells: Role of the Quality and Quantity of DC/DCleu and Anti-Leukemia-Directed T-Cells To Predict the Course and Success of Immunotherapy.

Blood ◽  
2006 ◽  
Vol 108 (11) ◽  
pp. 3246-3246
Author(s):  
Helga M. Schmetzer ◽  
Anja Liepert ◽  
Christine Grabrucker ◽  
Andreas Kremser ◽  
Julia Loibl ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Ex Vivo ◽  
Leukemic Cells ◽  
Cytotoxic Lymphocytes ◽  
Activated T Cells ◽  
Gm Csf ◽  
Donor T Cells

Abstract The presentation of leukemic antigens can be improved in AML and MDS by in vitro conversion of leukemic cells in leukemia-derived DC (DCleu), thereby forming a platform for the generation of leukemia-specific cytotoxic lymphocytes (CTL). In preliminary analyses with 140 AML and 60 MDS-cases we could already define optimal serum-free culture conditions to generate DC/DCleu.(Kufner 2005 I–III). Now we want to predict or correlate the clinical response to a DC/CTL-based immunotherapy by detailed analyses of the ex vivo generated/activated DC/DCleu and T-cells: 1)By a combination of 3 different DC-generating methods (‘MCM-mimic’, Lee 2003; ‘Ca-Ionophore’, Houtenbos 2003; ‘Picibanil’, Sato 2003) we can generate DC/DCleu in every case of AML/MDS, independently from FAB-type or karyotype. DC/DCleu are quantified according to their surface DC/blast-marker profiles. On average 42–45%/39–66% DC in AML/MDS could be generated with 48–54%/39–51% mature (CD83+) and 31–34%/23–31% migratory (CCR7+) DC. 45–65% of DC were ‘DCleu’; on average 47% of blasts are convertible to DCleu.. 2) In AML-patients who had presented with a relapse after SCT we could correlate a better ex vivo convertibility of blasts to DCleu with the patients’ in vivo response to a GM-CSF/Donor-lymphocyte Infusion (DLI)-therapy of their relapse after SCT (33% vs 7% to DCleu convertible blasts in ‘non-responders’). 3) A ‘Mixed lymphocyte culture’ (MLC) of autologous AML-patients’ or allogeneic donor-T-cells showed an on average higher proliferation and stimulation of DC-primed compared to MNC-primed T-cells: Upregulation of CD80/CD86-CD28;CD40-CD154;CD137L-CD137; moreover DC-priming yielded higher proportions of CD4+ cells, CD3+CD45RO+ memory cells CCR4+ T-cells (+59%, +52%, +91%) compared to MNC-primed T-cells (+35%, +13%, +44%) and a higher leukaemia-cytolytic activity (average 62%) compared to MNC-stimulated CTL (average 26%). 4) A detailed analysis of data showed great individual variations depending on the quality and composition of DC and T-cells: a) non-DC-primed autologous or allogeneic T-cells an lead to an increase of naive blasts after 3h incubation with blasts b) in cases with an ineffective DC-mediated ex vivo lysis of naïve blasts lower proportions of mature DC (29% vs 63%), DCleu (41% vs 68%) or a reduced T-cell proliferation or even loss of CD4/CD8/memory T-cells were seen. In summary our data show 1. that DC/DCleu can be generated in every single AML/MDS-case. 2. Grade of ex-vivo generability of DC/DCleu correlates with the in vivo response to a GM-CSF/DLI-relapse therapy. 3. Composition and quality of DC and autologous or donor T-cells after DC-priming provides informations about the activability and quality of CTLs in individual patients. We conclude, that ex vivo analysis of the DC/anti-leukemic T-cell-activability is necessary to develop and select promising anti-leukemia-directed T-cells for the immunotherapy of AML and MDS.

scholarly journals Biomarkers for Comorbidities Modulate the Activity of T-Cells in COPD

2021 ◽  
Vol 22 (13) ◽  
pp. 7187
Author(s):  
Kaschin Jamal Jameel ◽  
Willem-Jakob Gallert ◽  
Sarah D. Yanik ◽  
Susanne Panek ◽  
Juliane Kronsbein ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Systemic Inflammation ◽  
T Cell Activation ◽  
Cell Activation ◽  
Ex Vivo ◽  
Enzyme Linked Immunosorbent Assay ◽  
Activation Markers ◽  
Gm Csf

In smoking-induced chronic obstructive pulmonary disease (COPD), various comorbidities are linked to systemic inflammation and infection-induced exacerbations. The underlying mechanisms are unclear but might provide therapeutic targets. T-cell activity is central in systemic inflammation and for infection-defense mechanisms and might be influenced by comorbidities. Hypothesis: Circulating biomarkers of comorbidities modulate the activity of T-cells of the T-helper type 1 (Th1) and/or T-cytotoxic type 1 (Tc1). T-cells in peripheral blood mononuclear cells (PBMCs) from non-smokers (NS), current smokers without COPD (S), and COPD subjects (total n = 34) were ex vivo activated towards Th1/Tc1 and were then stimulated with biomarkers for metabolic and/or cardiovascular comorbidities (Brain Natriuretic Peptide, BNP; chemokine (C-C motif) ligand 18, CCL18; C-X3-C motif chemokine ligand 1, CX3CL1; interleukin-18, IL-18) or for asthma- and/or cancer-related comorbidities (CCL22; epidermal growth factor, EGF; IL-17; periostin) each at 10 or 50 ng/mL. The Th1/Tc1 activation markers interferon-γ (IFNγ), tumor necrosis factor-α (TNFα), and granulocyte-macrophage colony-stimulating factor (GM-CSF) were analyzed in culture supernatants by Enzyme-Linked Immunosorbent Assay (ELISA). Ex-vivo activation induced IFNγ and TNFα without differences between the groups but GM-CSF more in S vs. NS. At 10 ng/mL, the different biomarkers increased or reduced the T-cell activation markers without a clear trend for one direction in the different categories of comorbidities or for the different T-cell activation markers. At 50 ng/mL, there was a clear shift towards suppressive effects, particularly for the asthma— and cancer-related biomarkers and in cells of S and COPD. Comorbidities might suppress T-cell immunity in COPD. This could explain the association of comorbidities with frequent exacerbations.

Leukemia-Derived DC for T-Cell Therapy against AML Progenitor Cells

Blood ◽  
2008 ◽  
Vol 112 (11) ◽  
pp. 5442-5442
Author(s):  
Helga Schmetzer ◽  
Anja Liepert ◽  
Christine Grabrucker ◽  
Dorothea Fischbacher ◽  
Markus Freudenreich ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Memory T Cells ◽  
Ex Vivo ◽  
Response To Therapy ◽  
Lytic Activity ◽  
Cell Cytotoxicity ◽  
Gm Csf ◽  
Donor T Cells ◽  
T Cell Cytotoxicity

Abstract Presentation of leukemic antigens (LAA) can be improved by conversion of leukemic cells to leukemia derived DC (DCleu), thereby enabling the generation of leukemia specific CTL. DC/DCleu can be generated and quantified from every AML case with at least one of 3 different DC generating methods (Schmetzer 2007/2008). We want to enlight the role of the composition and quality of DC and (DC or blast trained) T cells to mediate leukemia cytotoxic reactions or to predict the clinical response to therapy. Autologous patients’, allogeneic donor T cells or T cells at relapse after SCT were trained with DC or blasts from 25 AML-cases in a ‘Mixed lymphocyte culture’ (MLC) and DC/T cell profiles and antileukemic Tcell cytotoxicity evaluated. We generated DC/mature DC/DCleu from every patient (Ø27/45/83%). DC training of T cells increased proliferating, CD4+ and memory T cells and decreased CD8+ T cells; blast training did not increase memory T cells. An antileukemic, very efficient T cell cytotoxicity was achieved in 47% of cases after DC/DCleu training but only in 24% after blast training of T cells. A comparison of cases with a gain of antileukemic T cell cytotoxicity to those without a lytic activity showed higher proportions of mature DC/DCleu and CD4/memory T cells and higher amounts of secreted IFNgamma and IL 6 in the lytically active, DC trained group. The differences were most distinct in the group with DC trained T cells prepared at relapse after SCT. Cases with a response to therapy showed higher proportions of DCleu, proliferating, memory or CD4+ T cells. We showed that >67% of all cases gained an antileukemic T cell cytotoxicity after DC training if >45% proliferating/>65% CD4+/>42% memory T cells or >40% mature DC/>65% DCleu were in the DC training setting. Moreover, 90% of DC trained T cells gained a lytic activity if >65% DCleu were in the MLC. AML patients presenting with a relapse after SCT showed better ex vivo convertibility of blasts to DCleu if they had responded to a GM CSF/DLI based therapy of their relapse after SCT compared to cases with no response (72 vs 36% blasts convertible to DCleu; 44 vs 29% generable DC). By spectratyping of the Vβ TCR region in an AML case we demonstrated a more extended clonal restriction of donor T cells after DC training of T cells compared to blast trained T cells. Moreover, the restricted pattern was also found in T cells from the patient after SCT. In summary, DC/DCleu can be generated in any given case independent from karyotype. A DC training of T cells improves the antileukaemic CTL, but can also mediate a T cell anergy. The composition of DC and T cells is predictive for the lytic efficiency of the trained T cells: A successful DC training of T cells is associated with high mature DC/DCleu counts and high rates of proliferating, CD4+ and memory T cells. Patients responding to a DLI/GM CSF based therapy are characterized by a better convertibility of blasts to DCleu and more mature DC. Identical clonal restrictions of T cells were found in blast trained and even more in DC trained T cells. Identical clonal patterns were found in ex vivo trained and in vivo selected T cells. We can contribute to understand biological mechanisms behind cytotoxic reactions and escape mechanisms and to develop adoptive immunotherapies with specific, antileukemia directed LAA specific T cells, e.g. selected by multimers from SCT donors or with specifically trained and selected T cells after DC training without side effects.

scholarly journals GMCSF modulates Myeloid derived suppressor cells and Tregs activity in decompensated cirrhotic patients with sepsis

2021 ◽  
Author(s):  
Rashi Sehgal ◽  
Rakhi Maiwall ◽  
Vijayraghavan Rajan ◽  
Mojahidul Islam ◽  
Sukriti Baweja ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Immune Cell ◽  
Ex Vivo ◽  
Suppressor Cells ◽  
T Cell Proliferation ◽  
Mrna Levels ◽  
Gm Csf ◽  
Cell Functions ◽  
Cell Functionality

Abstract Background Decompensated cirrhosis patients are more prone to bacterial infections. Myeloid derived suppressor cells (MDSCs) expand in sepsis patients and disrupt immune cell functions. GM-CSF therapy helps in restoring immune cell functions and resolve infections. Its role in MDSCs modulation in cirrhotic with sepsis is not well understood. Methods 164 decompensated cirrhotic; 62 without(w/o), 72 with sepsis and 30 with sepsis treated with GM-CSF and 15 healthy were studied. High-dimensional flow cytometry was performed to analyse MDSCs, monocytes, neutrophils, CD4 T-cells and Tregs at admission, day3 and 7. Ex-vivo co-cultured MDSCs with T-cells were assessed for proliferation and apoptosis of T-cells, differentiation to T-regs. Plasma factors and mRNA levels were analysed by cytokine-bead assay and qRT-PCR. Results Frequency of MDSCs and T-regs were significantly increased (p=0.011, and p=0.02) with decreased CD4 T-cells(p=0.01) in sepsis than without sepsis and HC (p=0.000, p=0.07 and p=0.01) at day0, and day7. In sepsis patients, MDSCs had increased IL-10, Arg1 and iNOS mRNA levels (p=0.016, p=0.049 and p=0.06). Ex-vivo co-cultured MDSCs with T-cells drove T-cell apoptosis (p=0.03, p=0.03) with decreased T-cell proliferation and enhanced FOXP3+ expression (p=0.05 and p=0.05) in sepsis compared to no sepsis at day0. Moreover, blocking the MDSCs with inhibitors suppressed FOXP3 expression. GM-CSF treatment in sepsis patients significantly decreased MDSCs and FOXP3+Tregs but increased CD4 T-cell functionality and improved survival. Conclusion MDSCs have immunosuppressive function by expanding FOXP3+ Tregs and inhibiting CD4+ T-cell proliferation in sepsis. GM-CSF treatment suppressed MDSCs, improved T-cell functionality and reduced Tregs in circulation.

scholarly journals Targeting CD38 is lethal to Breg-like chronic lymphocytic leukemia cells and Tregs, but restores CD8+ T-cell responses

2020 ◽  
Vol 4 (10) ◽  
pp. 2143-2157 ◽  
Author(s):  
Alak Manna ◽  
Timothy Kellett ◽  
Sonikpreet Aulakh ◽  
Laura J. Lewis-Tuffin ◽  
Navnita Dutta ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Chronic Lymphocytic Leukemia ◽  
Cd8 T Cells ◽  
Mononuclear Cells ◽  
Transforming Growth Factor ◽  
Ex Vivo ◽  
Xenograft Model ◽  
Lymphocytic Leukemia ◽  
Dependent Manner

Abstract Patients with chronic lymphocytic leukemia (CLL) are characterized by monoclonal expansion of CD5+CD23+CD27+CD19+κ/λ+ B lymphocytes and are clinically noted to have profound immune suppression. In these patients, it has been recently shown that a subset of B cells possesses regulatory functions and secretes high levels of interleukin 10 (IL-10). Our investigation identified that CLL cells with a CD19+CD24+CD38hi immunophenotype (B regulatory cell [Breg]–like CLL cells) produce high amounts of IL-10 and transforming growth factor β (TGF-β) and are capable of transforming naive T helper cells into CD4+CD25+FoxP3+ T regulatory cells (Tregs) in an IL-10/TGF-β-dependent manner. A strong correlation between the percentage of CD38+ CLL cells and Tregs was observed. CD38hi Tregs comprised more than 50% of Tregs in peripheral blood mononuclear cells (PBMCs) in patients with CLL. Anti-CD38 targeting agents resulted in lethality of both Breg-like CLL and Treg cells via apoptosis. Ex vivo, use of anti-CD38 monoclonal antibody (mAb) therapy was associated with a reduction in IL-10 and CLL patient-derived Tregs, but an increase in interferon-γ and proliferation of cytotoxic CD8+ T cells with an activated phenotype, which showed an improved ability to lyse patient-autologous CLL cells. Finally, effects of anti-CD38 mAb therapy were validated in a CLL–patient-derived xenograft model in vivo, which showed decreased percentage of Bregs, Tregs, and PD1+CD38hiCD8+ T cells, but increased Th17 and CD8+ T cells (vs vehicle). Altogether, our results demonstrate that targeting CD38 in CLL can modulate the tumor microenvironment; skewing T-cell populations from an immunosuppressive to immune-reactive milieu, thus promoting immune reconstitution for enhanced anti-CLL response.

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