| 1. |
- Bernson, Elin, 1987, et al.
(författare)
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Impact of killer-immunoglobulin-like receptor and human leukocyte antigen genotypes on the efficacy of immunotherapy in acute myeloid leukemia
- 2017
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Ingår i: Leukemia. - : Springer Science and Business Media LLC. - 0887-6924 .- 1476-5551. ; 31:12, s. 2552-2559
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Tidskriftsartikel (refereegranskat)abstract
- Interactions between killer-immunoglobulin-like receptors (KIRs) and their HLA class I ligands are instrumental in natural killer (NK) cell regulation and protect normal tissue from NK cell attack. Human KIR haplotypes comprise genes encoding mainly inhibitory receptors (KIR A) or activating and inhibitory receptors (KIR B). A substantial fraction of humans lack ligands for inhibitory KIRs (iKIRs), that is, a 'missing ligand' genotype. KIR B/x and missing ligand genotypes may thus give rise to potentially autoreactive, unlicensed NK cells. Little is known regarding the impact of such genotypes in untransplanted acute myeloid leukemia (AML). For this study, NK cell phenotypes and KIR/HLA genotypes were determined in 81 AML patients who received immunotherapy with histamine dihydrochloride and low-dose IL-2 for relapse prevention (NCT01347996). We observed that presence of unlicensed NK cells impacted favorably on clinical outcome, in particular among patients harboring functional NK cells reflected by high expression of the natural cytotoxicity receptor (NCR) NKp46. Genotype analyses suggested that the clinical benefit of high NCR expression was restricted to patients with a missing ligand genotype and/or a KIR B/x genotype. These data imply that functional NK cells are significant anti-leukemic effector cells in patients with KIR/HLA genotypes that favor NK cell autoreactivity.
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| 2. |
- Martner, Anna, 1979, et al.
(författare)
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NK cell expression of natural cytotoxicity receptors may determine relapse risk in older AML patients undergoing immunotherapy for remission maintenance.
- 2015
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Ingår i: Oncotarget. - : Impact Journals, LLC. - 1949-2553. ; 6:40, s. 42569-74
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Tidskriftsartikel (refereegranskat)abstract
- In a phase IV trial, eighty-four patients (age 18-79) with acute myeloid leukemia (AML) in first complete remission (CR) received cycles of immunotherapy with histamine dihydrochloride (HDC) and low-dose human recombinant interleukin-2 (IL-2) to prevent relapse in the post-consolidation phase. Aspects of natural killer (NK) cell biology were analyzed before and during immunotherapy with focus on outcome in older patients. In younger (<60 years old, n = 37) and older patients (>60 years old, n = 47), treatment with HDC/IL-2 resulted in an expansion of CD56bright and CD16+ NK cells in blood along with an increased NK cell expression of the natural cytotoxicity receptors (NCR) NKp30 and NKp46. In older patients, a high expression of NKp30 or NKp46 on CD16+ NK cells before and during therapy predicted leukemia-free and overall survival. These results suggest that NK cell functions determine relapse risk and survival in older AML patients and point to biomarkers of efficacy in protocols for remission maintenance.
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| 3. |
- Martner, Anna, 1979, et al.
(författare)
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Redox Remodeling by Dendritic Cells Protects Antigen-Specific T Cells against Oxidative Stress
- 2011
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Ingår i: Journal of Immunology. - : The American Association of Immunologists. - 1550-6606 .- 0022-1767. ; 187:12, s. 6243-8
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Tidskriftsartikel (refereegranskat)abstract
- Microorganisms and microbial products induce the release of reactive oxygen species (ROS) from monocytes and other myeloid cells, which may trigger dysfunction and apoptosis of adjacent lymphocytes. Therefore, T cell-mediated immunity is likely to comprise mechanisms of T cell protection against ROS-inflicted toxicity. The present study aimed to clarify the dynamics of reduced sulfhydryl groups (thiols) in human T cells after presentation of viral and bacterial Ags by dendritic cells (DCs) or B cells. DCs, but not B cells, efficiently triggered intra- and extracellular thiol expression in T cells with corresponding Ag specificity. After interaction with DCs, the Ag-specific T cells acquired the capacity to neutralize exogenous oxygen radicals and resisted ROS-induced apoptosis. Our results imply that DCs provide Ag-specific T cells with antioxidative thiols during Ag presentation, which suggests a novel aspect of DC/T cell cross-talk of relevance to the maintenance of specific immunity in inflamed or infected tissue.
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| 4. |
- Martner, Anna, 1979, et al.
(författare)
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Role of natural killer cell subsets and natural cytotoxicity receptors for the outcome of immunotherapy in acute myeloid leukemia
- 2016
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Ingår i: Oncoimmunology. - : Informa UK Limited. - 2162-402X. ; 5:1
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Tidskriftsartikel (refereegranskat)abstract
- In a phase IV trial, 84 patients (age 18-79) with acute myeloid leukemia (AML) in first complete remission (CR) received cycles of immunotherapy with histamine dihydrochloride (HDC) and low-dose human recombinant interleukin 2 (IL-2) for 18 months to prevent leukemic relapse. During cycles, the treatment resulted in expansion of CD56(bright) (CD3 /16 /56(bright)) and CD16(+) (CD3 /16(+)/56(+)) natural killer (NK) cells in the blood along with increased NK cell expression of the natural cytotoxicity receptors (NCRs) NKp30 and NKp46. Multivariate analyses correcting for age and risk group demonstrated that high CD56(bright) NK cell counts and high expression of NKp30 or NKp46 on CD16(+) NK cells independently predicted leukemia-free survival (LFS) and overall survival (OS). Our results suggest that the dynamics of NK cell subsets and their NCR expression may determine the efficiency of relapse-preventive immunotherapy in AML.
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| 5. |
- Rydström, Anna, 1976, et al.
(författare)
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Dynamics of myeloid cell populations during relapse-preventive immunotherapy in acute myeloid leukemia
- 2017
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Ingår i: Journal of Leukocyte Biology. - 0741-5400. ; 102:2, s. 467-474
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Tidskriftsartikel (refereegranskat)abstract
- Relapse of leukemia in the postchemotherapy phase contributes to the poor prognosis and survival in patients with acute myeloid leukemia (AML). In an international phase IV trial (ClinicalTrials.gov; NCT01347996), 84 patients with AML in first complete remission who had not undergone transplantation received immunotherapy with histamine dihydrochloride (HDC) and low-dose IL-2 with the aim of preventing relapse. The dynamics of myeloid cell counts and expression of activation markers was assessed before and after cycles of immunotherapy and correlated with clinical outcome in terms of relapse risk and survival. During cycles, a pronounced increase in blood eosinophil counts was observed along with a reduction in monocyte and neutrophil counts. A strong reduction of blood monocyte counts during the first HDC/IL-2 treatment cycle predicted leukemia-free survival. The HDC component of the immunotherapy exerts agonist activity at histamine type 2 receptors (H2Rs) that are expressed by myeloid cells. It was observed that the density of H-2 R expression in blood monocytes increased during cycles of immunotherapy and that high monocyte H2R expression implied reduced relapse risk and improved overall survival. Several other activation markers, including HLA-DR, CD86, and CD40, were induced in monocytes and dendritic cells during immunotherapy but did not predict clinical outcome. In addition, expression of HLA-ABC increased in all myeloid populations during therapy. A low expression of HLA-ABC was associated with reduced relapse risk. These results suggest that aspects of myeloid cell biology may impact clinical benefit of relapse-preventive immunotherapy in AML.
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| 6. |
- Sander, Frida Ewald, et al.
(författare)
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Dynamics of cytotoxic T cell subsets during immunotherapy predicts outcome in acute myeloid leukemia
- 2016
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Ingår i: Oncotarget. - : Impact Journals, LLC. - 1949-2553. ; 7:7, s. 7586-7596
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Tidskriftsartikel (refereegranskat)abstract
- Preventing relapse after chemotherapy remains a challenge in acute myeloid leukemia (AML). Eighty-four non-transplanted AML patients in first complete remission received relapse-preventive immunotherapy with histamine dihydrochloride and low-dose interleukin-2 in an international phase IV trial (ClinicalTrials.gov; NCT01347996). Blood samples were drawn during cycles of immunotherapy and analyzed for CD8(+) (cytotoxic) T cell phenotypes in blood. During the first cycle of therapy, a re-distribution of cytotoxic T cells was observed comprising a reduction of T effector memory cells and a concomitant increase of T effector cells. The dynamics of T cell subtypes during immunotherapy prognosticated relapse and survival, in particular among older patients and remained significantly predictive of clinical outcome after correction for potential confounders. Presence of CD8(+) T cells with specificity for leukemia-associated antigens identified patients with low relapse risk. Our results point to novel aspects of T cell-mediated immunosurveillance in AML and provide conceivable biomarkers in relapse-preventive immunotherapy.
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| 7. |
- Sander, Frida Ewald, et al.
(författare)
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Role of regulatory T cells in acute myeloid leukemia patients undergoing relapse-preventive immunotherapy
- 2017
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Ingår i: Cancer Immunology Immunotherapy. - : Springer Science and Business Media LLC. - 0340-7004 .- 1432-0851. ; 66:11, s. 1473-1484
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Tidskriftsartikel (refereegranskat)abstract
- Regulatory T cells - (Tregs) have been proposed to dampen functions of anti-neoplastic immune cells and thus promote cancer progression. In a phase IV trial (Re: Mission Trial, NCT01347996, http://www.clinicaltrials.gov) 84 patients (age 18-79) with acute myeloid leukemia (AML) in first complete remission (CR) received ten consecutive 3-week cycles of immunotherapy with histamine dihydrochloride (HDC) and low-dose interleukin-2 (IL-2) to prevent relapse of leukemia in the post-consolidation phase. This study aimed at defining the features, function and dynamics of Foxp3(+)CD25(high)CD4(+) T-regs during immunotherapy and to determine the potential impact of T-regs on relapse risk and survival. We observed a pronounced increase in T-reg counts in peripheral blood during initial cycles of HDC/IL-2. The accumulating T-regs resembled thymic-derived natural T-regs (nT(regs)), showed augmented expression of CTLA-4 and suppressed the cell cycle proliferation of conventional T cells ex vivo. Relapse of AML was not prognosticated by T-reg counts at onset of treatment or after the first cycle of immunotherapy. However, the magnitude of T-reg induction was diminished in subsequent treatment cycles. Exploratory analyses implied that a reduced expansion of T-regs in later treatment cycles and a short T-reg telomere length were significantly associated with a favorable clinical outcome. Our results suggest that immunotherapy with HDC/IL-2 in AML entails induction of immunosuppressive T-regs that may be targeted for improved anti-leukemic efficiency.
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| 8. |
- TIGERSTRÖM, ANNA KATARINA, 1976, et al.
(författare)
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Functional split and crosslinking of the membrane domain of the beta subunit of proton-translocating transhydrogenase from Escherichia coli
- 2003
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Ingår i: Biochemistry. - : American Chemical Society (ACS). - 0006-2960 .- 1520-4995. ; 42, s. 10998-11003
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Tidskriftsartikel (refereegranskat)abstract
- Proton pumping nicotinamide nucleotide transhydrogenase from Escherichia coli contains an alpha subunit with the NAD(H)-binding domain I and a beta subunit with the NADP(H)-binding domain III. The membrane domain (domain II) harbors the proton channel and is made up of the hydrophobic parts of the alpha and beta subunits. The interface in domain II between the alpha and the beta subunits has previously been investigated by cross-linking loops connecting the four transmembrane helices in the alpha subunit and loops connecting the nine transmembrane helices in the beta subunit. However, to investigate the organization of the nine transmembrane helices in the beta subunit, a split was introduced by creating a stop codon in the loop connecting transmembrane helices 9 and 10 by a single mutagenesis step, utilizing an existing downstream start codon. The resulting enzyme was composed of the wild-type alpha subunit and the two new peptides beta1 and beta2. As compared to other split membrane proteins, the new transhydrogenase was remarkably active and catalyzed activities for the reduction of 3-acetylpyridine-NAD(+) by NADPH, the cyclic reduction of 3-acetylpyridine-NAD(+) by NADH (mediated by bound NADP(H)), and proton pumping, amounting to about 50-107% of the corresponding wild-type activities. These high activities suggest that the alpha subunit was normally folded, followed by a concerted folding of beta1 + beta2. Cross-linking of a betaS105C-betaS237C double cysteine mutant in the functional split cysteine-free background, followed by SDS-PAGE analysis, showed that helices 9, 13, and 14 were in close proximity. This is the first time that cross-linking between helices in the same beta subunit has been demonstrated.
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| 9. |
- Grauers Wiktorin, Hanna, 1990, et al.
(författare)
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Histamine targets myeloid-derived suppressor cells and improves the anti-tumor efficacy of PD-1/PD-L1 checkpoint blockade
- 2019
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Ingår i: Cancer Immunology Immunotherapy. - : Springer Science and Business Media LLC. - 0340-7004 .- 1432-0851. ; 68:2, s. 163-174
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Tidskriftsartikel (refereegranskat)abstract
- Myeloid-derived suppressor cells (MDSCs) are immature monocytes and granulocytes that impede immune-mediated clearance of malignant cells by multiple mechanisms, including the formation of immunosuppressive reactive oxygen species (ROS) via the myeloid cell NADPH oxidase (NOX2). Histamine dihydrochloride (HDC), a NOX2 inhibitor, exerts anti-cancer efficacy in experimental tumor models but the detailed mechanisms are insufficiently understood. To determine effects of HDC on the MDSC compartment we utilized three murine cancer models known to entail accumulation of MDSC, i.e. EL-4 lymphoma, MC-38 colorectal carcinoma, and 4T1 mammary carcinoma. In vivo treatment with HDC delayed EL-4 and 4T1 tumor growth and reduced the ROS formation by intratumoral MDSCs. HDC treatment of EL-4 bearing mice also reduced the accumulation of intratumoral MDSCs and reduced MDSC-induced suppression of T cells ex vivo. Experiments using GR1-depleted and Nox2 knock out mice supported that the anti-tumor efficacy of HDC required presence of NOX2(+) GR1(+) cells in vivo. In addition, treatment with HDC enhanced the anti-tumor efficacy of programmed cell death receptor 1 (PD-1) and PD-1 ligand checkpoint blockade in EL-4- and MC-38-bearing mice. Immunomodulatory effects of a HDC-containing regimen on MDSCs were further analyzed in a phase IV trial (Re:Mission Trial, ClinicalTrials.gov; NCT01347996) where patients with acute myeloid leukemia received HDC in conjunction with low-dose IL-2 (HDC/IL-2) for relapse prevention. Peripheral CD14(+)HLA-DR-/low MDSCs (M-MDSCs) were reduced during cycles of HDC/IL-2 therapy and a pronounced reduction of M-MDSCs during HDC/IL-2 treatment heralded favorable clinical outcome. We propose that anti-tumor properties of HDC may comprise the targeting of MDSCs.
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| 10. |
- Tam, Miguel A., 1976, et al.
(författare)
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Early cellular responses to Salmonella infection: dendritic cells, monocytes, and more.
- 2008
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Ingår i: Immunological reviews. - 1600-065X. ; 225, s. 140-62
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Forskningsöversikt (refereegranskat)abstract
- SUMMARY: Dendritic cells (DCs), monocytes, macrophages, and neutrophils are myeloid-derived phagocytes critical to controlling bacterial infections, and these cells have complementary functions to ensure host survival. Recent data have shed light on the dynamics and function of myeloid cells at the early stage of infection. In particular, murine infection models with Salmonella enterica serovar Typhimurium have been useful for understanding the host response required to develop immunity to systemic salmonellosis. This review summarizes the early cellular responses in the intestinal lymphoid tissues to Salmonella and discusses Peyer's patch-dependent and -independent penetration of bacteria through the intestinal epithelium. Once Salmonella accesses host tissue, phagocytes respond by recruitment, redistribution, and activation in intestinal tissues. Recruited monocytes are specialized in controlling bacterial replication by producing anti-microbial molecules but are poor antigen-presenting cells. In contrast, DCs undergo maturation by direct (bacteria-mediated) and indirect (cytokine-mediated) pathways in vivo to optimize their antigen presentation capacity, and directly matured DCs have unique mechanisms to ensure T-cell stimulation. Toll-like receptor signaling is critical to DC maturation and myeloid cell recruitment during Salmonella infection, and the role of myeloid differentiation factor 88 (MyD88)-dependent and MyD88-independent pathways as well as proinflammatory cytokines and type 1 interferons in these processes are discussed.
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