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1.
Cell ; 185(17): 3263-3277.e15, 2022 08 18.
Article in English | MEDLINE | ID: mdl-35931082

ABSTRACT

Live bacterial therapeutics (LBTs) could reverse diseases by engrafting in the gut and providing persistent beneficial functions in the host. However, attempts to functionally manipulate the gut microbiome of conventionally raised (CR) hosts have been unsuccessful because engineered microbial organisms (i.e., chassis) have difficulty in colonizing the hostile luminal environment. In this proof-of-concept study, we use native bacteria as chassis for transgene delivery to impact CR host physiology. Native Escherichia coli bacteria isolated from the stool cultures of CR mice were modified to express functional genes. The reintroduction of these strains induces perpetual engraftment in the intestine. In addition, engineered native E. coli can induce functional changes that affect physiology of and reverse pathology in CR hosts months after administration. Thus, using native bacteria as chassis to "knock in" specific functions allows mechanistic studies of specific microbial activities in the microbiome of CR hosts and enables LBT with curative intent.


Subject(s)
Gastrointestinal Microbiome , Microbiota , Animals , Bacteria/genetics , Escherichia coli/genetics , Gastrointestinal Microbiome/physiology , Mice , Transgenes
2.
Cell ; 173(5): 1135-1149.e15, 2018 05 17.
Article in English | MEDLINE | ID: mdl-29754817

ABSTRACT

A primary cause of disease progression in type 2 diabetes (T2D) is ß cell dysfunction due to inflammatory stress and insulin resistance. However, preventing ß cell exhaustion under diabetic conditions is a major therapeutic challenge. Here, we identify the vitamin D receptor (VDR) as a key modulator of inflammation and ß cell survival. Alternative recognition of an acetylated lysine in VDR by bromodomain proteins BRD7 and BRD9 directs association to PBAF and BAF chromatin remodeling complexes, respectively. Mechanistically, ligand promotes VDR association with PBAF to effect genome-wide changes in chromatin accessibility and enhancer landscape, resulting in an anti-inflammatory response. Importantly, pharmacological inhibition of BRD9 promotes PBAF-VDR association to restore ß cell function and ameliorate hyperglycemia in murine T2D models. These studies reveal an unrecognized VDR-dependent transcriptional program underpinning ß cell survival and identifies the VDR:PBAF/BAF association as a potential therapeutic target for T2D.


Subject(s)
Chromosomal Proteins, Non-Histone/metabolism , Insulin-Secreting Cells/drug effects , Receptors, Calcitriol/metabolism , Transcription Factors/metabolism , Vitamin D/pharmacology , Animals , Calcitriol/analogs & derivatives , Calcitriol/pharmacology , Chromatin Assembly and Disassembly , Diabetes Mellitus, Experimental/chemically induced , Diabetes Mellitus, Experimental/metabolism , Diabetes Mellitus, Experimental/pathology , Humans , Insulin/blood , Insulin/metabolism , Insulin-Secreting Cells/cytology , Insulin-Secreting Cells/metabolism , Male , Mice , Mice, Inbred C57BL , Mice, Obese , Mutagenesis, Site-Directed , Oxidative Phosphorylation/drug effects , Protein Binding , RNA Interference , RNA, Guide, Kinetoplastida/genetics , RNA, Small Interfering/metabolism , Receptors, Calcitriol/antagonists & inhibitors , Receptors, Calcitriol/genetics , Transcription Factors/antagonists & inhibitors , Transcription Factors/genetics , Transcription, Genetic/drug effects
3.
Immunity ; 54(7): 1561-1577.e7, 2021 07 13.
Article in English | MEDLINE | ID: mdl-34102100

ABSTRACT

A common metabolic alteration in the tumor microenvironment (TME) is lipid accumulation, a feature associated with immune dysfunction. Here, we examined how CD8+ tumor infiltrating lymphocytes (TILs) respond to lipids within the TME. We found elevated concentrations of several classes of lipids in the TME and accumulation of these in CD8+ TILs. Lipid accumulation was associated with increased expression of CD36, a scavenger receptor for oxidized lipids, on CD8+ TILs, which also correlated with progressive T cell dysfunction. Cd36-/- T cells retained effector functions in the TME, as compared to WT counterparts. Mechanistically, CD36 promoted uptake of oxidized low-density lipoproteins (OxLDL) into T cells, and this induced lipid peroxidation and downstream activation of p38 kinase. Inhibition of p38 restored effector T cell functions in vitro, and resolution of lipid peroxidation by overexpression of glutathione peroxidase 4 restored functionalities in CD8+ TILs in vivo. Thus, an oxidized lipid-CD36 axis promotes intratumoral CD8+ T cell dysfunction and serves as a therapeutic avenue for immunotherapies.


Subject(s)
CD36 Antigens/metabolism , CD8-Positive T-Lymphocytes/metabolism , Lipid Peroxidation/physiology , Lipoproteins, LDL/metabolism , Neoplasms/metabolism , Receptors, Scavenger/metabolism , Animals , Biological Transport/physiology , Cell Line, Tumor , HEK293 Cells , Humans , Leukocytes, Mononuclear/metabolism , Lymphocytes, Tumor-Infiltrating/metabolism , Mice , Mice, Inbred C57BL , Mice, Transgenic , Tumor Microenvironment/physiology
4.
Nature ; 609(7928): 846-853, 2022 09.
Article in English | MEDLINE | ID: mdl-35940205

ABSTRACT

Thyroid hormones are vital in metabolism, growth and development1. Thyroid hormone synthesis is controlled by thyrotropin (TSH), which acts at the thyrotropin receptor (TSHR)2. In patients with Graves' disease, autoantibodies that activate the TSHR pathologically increase thyroid hormone activity3. How autoantibodies mimic thyrotropin function remains unclear. Here we determined cryo-electron microscopy structures of active and inactive TSHR. In inactive TSHR, the extracellular domain lies close to the membrane bilayer. Thyrotropin selects an upright orientation of the extracellular domain owing to steric clashes between a conserved hormone glycan and the membrane bilayer. An activating autoantibody from a patient with Graves' disease selects a similar upright orientation of the extracellular domain. Reorientation of the extracellular domain transduces a conformational change in the seven-transmembrane-segment domain via a conserved hinge domain, a tethered peptide agonist and a phospholipid that binds within the seven-transmembrane-segment domain. Rotation of the TSHR extracellular domain relative to the membrane bilayer is sufficient for receptor activation, revealing a shared mechanism for other glycoprotein hormone receptors that may also extend to other G-protein-coupled receptors with large extracellular domains.


Subject(s)
Cryoelectron Microscopy , Immunoglobulins, Thyroid-Stimulating , Receptors, Thyrotropin , Thyrotropin , Cell Membrane/metabolism , Graves Disease/immunology , Graves Disease/metabolism , Humans , Immunoglobulins, Thyroid-Stimulating/chemistry , Immunoglobulins, Thyroid-Stimulating/immunology , Immunoglobulins, Thyroid-Stimulating/pharmacology , Immunoglobulins, Thyroid-Stimulating/ultrastructure , Phospholipids/metabolism , Protein Domains , Receptors, G-Protein-Coupled/agonists , Receptors, G-Protein-Coupled/chemistry , Receptors, G-Protein-Coupled/ultrastructure , Receptors, Thyrotropin/agonists , Receptors, Thyrotropin/chemistry , Receptors, Thyrotropin/immunology , Receptors, Thyrotropin/ultrastructure , Rotation , Thyrotropin/chemistry , Thyrotropin/metabolism , Thyrotropin/pharmacology
5.
Nature ; 586(7831): 790-795, 2020 10.
Article in English | MEDLINE | ID: mdl-32788725

ABSTRACT

Serine, glycine and other nonessential amino acids are critical for tumour progression, and strategies to limit their availability are emerging as potential therapies for cancer1-3. However, the molecular mechanisms driving this response remain unclear and the effects on lipid metabolism are relatively unexplored. Serine palmitoyltransferase (SPT) catalyses the de novo biosynthesis of sphingolipids but also produces noncanonical 1-deoxysphingolipids when using alanine as a substrate4,5. Deoxysphingolipids accumulate in the context of mutations in SPTLC1 or SPTLC26,7-or in conditions of low serine availability8,9-to drive neuropathy, and deoxysphinganine has previously been investigated as an anti-cancer agent10. Here we exploit amino acid metabolism and the promiscuity of SPT to modulate the endogenous synthesis of toxic deoxysphingolipids and slow tumour progression. Anchorage-independent growth reprogrammes a metabolic network involving serine, alanine and pyruvate that drives the endogenous synthesis and accumulation of deoxysphingolipids. Targeting the mitochondrial pyruvate carrier promotes alanine oxidation to mitigate deoxysphingolipid synthesis and improve spheroid growth, similar to phenotypes observed with the direct inhibition of SPT or ceramide synthesis. Restriction of dietary serine and glycine potently induces the accumulation of deoxysphingolipids while decreasing tumour growth in xenograft models in mice. Pharmacological inhibition of SPT rescues xenograft growth in mice fed diets restricted in serine and glycine, and the reduction of circulating serine by inhibition of phosphoglycerate dehydrogenase (PHGDH) leads to the accumulation of deoxysphingolipids and mitigates tumour growth. The promiscuity of SPT therefore links serine and mitochondrial alanine metabolism to membrane lipid diversity, which further sensitizes tumours to metabolic stress.


Subject(s)
Neoplasms/metabolism , Neoplasms/pathology , Serine/deficiency , Sphingolipids/chemistry , Sphingolipids/metabolism , Alanine/biosynthesis , Alanine/metabolism , Alanine/pharmacology , Animals , Cell Adhesion/drug effects , Cell Division/drug effects , Diet , Female , Glycine/biosynthesis , Glycine/deficiency , Glycine/metabolism , Glycine/pharmacology , HCT116 Cells , Humans , Membrane Lipids/chemistry , Membrane Lipids/metabolism , Mice , Mitochondria/metabolism , Neoplasms/drug therapy , Phosphoglycerate Dehydrogenase/antagonists & inhibitors , Phosphoglycerate Dehydrogenase/metabolism , Pyruvic Acid/metabolism , Serine/blood , Serine/pharmacology , Serine C-Palmitoyltransferase/antagonists & inhibitors , Serine C-Palmitoyltransferase/metabolism , Spheroids, Cellular/pathology , Sphingolipids/biosynthesis , Stress, Physiological/drug effects , Xenograft Model Antitumor Assays
6.
Proc Natl Acad Sci U S A ; 120(50): e2314429120, 2023 Dec 12.
Article in English | MEDLINE | ID: mdl-38055739

ABSTRACT

We detected ENU-induced alleles of Mfsd1 (encoding the major facilitator superfamily domain containing 1 protein) that caused lymphopenia, splenomegaly, progressive liver pathology, and extramedullary hematopoiesis (EMH). MFSD1 is a lysosomal membrane-bound solute carrier protein with no previously described function in immunity. By proteomic analysis, we identified association between MFSD1 and both GLMP (glycosylated lysosomal membrane protein) and GIMAP5 (GTPase of immunity-associated protein 5). Germline knockout alleles of Mfsd1, Glmp, and Gimap5 each caused lymphopenia, liver pathology, EMH, and lipid deposition in the bone marrow and liver. We found that the interactions of MFSD1 and GLMP with GIMAP5 are essential to maintain normal GIMAP5 expression, which in turn is critical to support lymphocyte development and liver homeostasis that suppresses EMH. These findings identify the protein complex MFSD1-GLMP-GIMAP5 operating in hematopoietic and extrahematopoietic tissues to regulate immunity and liver homeostasis.


Subject(s)
GTP-Binding Proteins , Lymphopenia , Humans , GTP-Binding Proteins/metabolism , Proteomics , Liver/metabolism , Lymphocytes/metabolism , Lymphopenia/genetics , Homeostasis
7.
J Biol Chem ; 300(5): 107291, 2024 May.
Article in English | MEDLINE | ID: mdl-38636661

ABSTRACT

Mutations in the adiponectin receptor 1 gene (AdipoR1) lead to retinitis pigmentosa and are associated with age-related macular degeneration. This study explores the effects of AdipoR1 gene deficiency in mice, revealing a striking decline in ω3 polyunsaturated fatty acids (PUFA), an increase in ω6 fatty acids, and elevated ceramides in the retina. The AdipoR1 deficiency impairs peroxisome proliferator-activated receptor α signaling, which is crucial for FA metabolism, particularly affecting proteins associated with FA transport and oxidation in the retina and retinal pigmented epithelium. Our lipidomic and proteomic analyses indicate changes that could affect membrane composition and viscosity through altered ω3 PUFA transport and synthesis, suggesting a potential influence of AdipoR1 on these properties. Furthermore, we noted a reduction in the Bardet-Biedl syndrome proteins, which are crucial for forming and maintaining photoreceptor outer segments that are PUFA-enriched ciliary structures. Diminution in Bardet-Biedl syndrome-proteins content combined with our electron microscopic observations raises the possibility that AdipoR1 deficiency might impair ciliary function. Treatment with inhibitors of ceramide synthesis led to substantial elevation of ω3 LC-PUFAs, alleviating photoreceptor degeneration and improving retinal function. These results serve as the proof of concept for a ceramide-targeted strategy to treat retinopathies linked to PUFA deficiency, including age-related macular degeneration.


Subject(s)
Ceramides , Receptors, Adiponectin , Retina , Animals , Receptors, Adiponectin/metabolism , Receptors, Adiponectin/genetics , Mice , Ceramides/metabolism , Retina/metabolism , Retina/pathology , Mice, Knockout , Fatty Acids, Unsaturated/metabolism , Retinal Pigment Epithelium/metabolism , Macular Degeneration/metabolism , Macular Degeneration/pathology , Macular Degeneration/genetics
8.
N Engl J Med ; 386(4): 351-363, 2022 01 27.
Article in English | MEDLINE | ID: mdl-34904799

ABSTRACT

BACKGROUND: Diffuse large B-cell lymphoma (DLBCL) is typically treated with rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP). However, only 60% of patients are cured with R-CHOP. Polatuzumab vedotin is an antibody-drug conjugate targeting CD79b, which is ubiquitously expressed on the surface of malignant B cells. METHODS: We conducted a double-blind, placebo-controlled, international phase 3 trial to evaluate a modified regimen of R-CHOP (pola-R-CHP), in which vincristine was replaced with polatuzumab vedotin, as compared with standard R-CHOP, in patients with previously untreated intermediate-risk or high-risk DLBCL. Patients 18 to 80 years of age were randomly assigned in a 1:1 ratio to receive six cycles of either pola-R-CHP or R-CHOP, plus two cycles of rituximab alone. The primary end point was investigator-assessed progression-free survival. Secondary end points included overall survival and safety. RESULTS: Overall, 879 patients underwent randomization: 440 were assigned to the pola-R-CHP group and 439 to the R-CHOP group. After a median follow-up of 28.2 months, the percentage of patients surviving without progression was significantly higher in the pola-R-CHP group than in the R-CHOP group (76.7% [95% confidence interval (CI), 72.7 to 80.8] vs. 70.2% [95% CI, 65.8 to 74.6] at 2 years; stratified hazard ratio for progression, relapse, or death, 0.73 by Cox regression; 95% CI, 0.57 to 0.95; P = 0.02). Overall survival at 2 years did not differ significantly between the groups (88.7% [95% CI, 85.7 to 91.6] in the pola-R-CHP group and 88.6% [95% CI, 85.6 to 91.6] in the R-CHOP group; hazard ratio for death, 0.94; 95% CI, 0.65 to 1.37; P = 0.75). The safety profile was similar in the two groups. CONCLUSIONS: Among patients with previously untreated intermediate-risk or high-risk DLBCL, the risk of disease progression, relapse, or death was lower among those who received pola-R-CHP than among those who received R-CHOP. (Funded by F. Hoffmann-La Roche/Genentech; POLARIX ClinicalTrials.gov number, NCT03274492.).


Subject(s)
Antibodies, Monoclonal/administration & dosage , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Immunoconjugates/administration & dosage , Lymphoma, Large B-Cell, Diffuse/drug therapy , Adult , Aged , Antibodies, Monoclonal/adverse effects , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Cyclophosphamide/adverse effects , Cyclophosphamide/therapeutic use , Double-Blind Method , Doxorubicin/adverse effects , Doxorubicin/therapeutic use , Female , Humans , Immunoconjugates/adverse effects , Lymphoma, Large B-Cell, Diffuse/mortality , Male , Middle Aged , Prednisone/adverse effects , Prednisone/therapeutic use , Progression-Free Survival , Rituximab/adverse effects , Rituximab/therapeutic use , Vincristine/adverse effects , Vincristine/therapeutic use
9.
Nat Chem Biol ; 19(2): 187-197, 2023 02.
Article in English | MEDLINE | ID: mdl-36266352

ABSTRACT

Lipids contribute to the structure, development, and function of healthy brains. Dysregulated lipid metabolism is linked to aging and diseased brains. However, our understanding of lipid metabolism in aging brains remains limited. Here we examined the brain lipidome of mice across their lifespan using untargeted lipidomics. Co-expression network analysis highlighted a progressive decrease in 3-sulfogalactosyl diacylglycerols (SGDGs) and SGDG pathway members, including the potential degradation products lyso-SGDGs. SGDGs show an age-related decline specifically in the central nervous system and are associated with myelination. We also found that an SGDG dramatically suppresses LPS-induced gene expression and release of pro-inflammatory cytokines from macrophages and microglia by acting on the NF-κB pathway. The detection of SGDGs in human and macaque brains establishes their evolutionary conservation. This work enhances interest in SGDGs regarding their roles in aging and inflammatory diseases and highlights the complexity of the brain lipidome and potential biological functions in aging.


Subject(s)
Aging , Lipids , Animals , Humans , Mice , Aging/genetics , Anti-Inflammatory Agents , Brain/metabolism , Microglia/metabolism , NF-kappa B/metabolism
10.
Arterioscler Thromb Vasc Biol ; 44(9): 2069-2087, 2024 Sep.
Article in English | MEDLINE | ID: mdl-39087348

ABSTRACT

BACKGROUND: Dyslipidemia increases cardiovascular disease risk, the leading cause of death worldwide. Under time-restricted feeding (TRF), wherein food intake is restricted to a consistent window of <12 hours, weight gain, glucose intolerance, inflammation, dyslipidemia, and hypercholesterolemia are all reduced in mice fed an obesogenic diet. LDLR (low-density lipoprotein receptor) mutations are a major cause of familial hypercholesterolemia and early-onset cardiovascular disease. METHODS: We subjected benchmark preclinical models, mice lacking LDLR-knockout or ApoE knockout to ad libitum feeding of an isocaloric atherogenic diet either ad libitum or 9 hours TRF for up to 13 weeks and assessed disease development, mechanism, and global changes in hepatic gene expression and plasma lipids. In a regression model, a subset of LDLR-knockout mice were ad libitum fed and then subject to TRF. RESULTS: TRF could significantly attenuate weight gain, hypercholesterolemia, and atherosclerosis in mice lacking the LDLR-knockout mice under experimental conditions of both prevention and regression. In LDLR-knockout mice, increased hepatic expression of genes mediating ß-oxidation during fasting is associated with reduced VLDL (very-low-density lipoprotein) secretion and lipid accumulation. Additionally, increased sterol catabolism coupled with fecal loss of cholesterol and bile acids contributes to the atheroprotective effect of TRF. Finally, TRF alone or combined with a cholesterol-free diet can reduce atherosclerosis in LDLR-knockout mice. However, mice lacking ApoE, which is an important protein for hepatic lipoprotein reuptake do not respond to TRF. CONCLUSIONS: In a preclinical animal model, TRF is effective in both the prevention and regression of atherosclerosis in LDLR knockout mice. The results suggest TRF alone or in combination with a low-cholesterol diet can be a lifestyle intervention for reducing cardiovascular disease risk in humans.


Subject(s)
Atherosclerosis , Disease Models, Animal , Liver , Mice, Knockout, ApoE , Receptors, LDL , Animals , Receptors, LDL/genetics , Receptors, LDL/deficiency , Atherosclerosis/prevention & control , Atherosclerosis/genetics , Atherosclerosis/metabolism , Atherosclerosis/etiology , Liver/metabolism , Male , Mice, Inbred C57BL , Time Factors , Fasting/blood , Mice , Hypercholesterolemia/genetics , Hypercholesterolemia/metabolism , Hypercholesterolemia/complications , Diet, Atherogenic , Weight Gain , Mice, Knockout , Aortic Diseases/prevention & control , Aortic Diseases/genetics , Aortic Diseases/pathology , Aortic Diseases/metabolism , Lipids/blood , Apolipoproteins E
11.
Br J Haematol ; 2024 Aug 01.
Article in English | MEDLINE | ID: mdl-39091109

ABSTRACT

We demonstrated that dose-densified and dose-intensified ABVD (doxorubicin, bleomycin, vinblastine, dacarbazine; ABVDDD-DI) was safe and effective. Here, we present a post hoc long-term analysis of the 82 patients enrolled in the original study. The median observation time was 175 months (IQR 159-197). At 15 years, progression-free and overall survival rates were 81.2% (95% CI, 69.9%-88.7%) and 92.7% (95% CI, 82.6%-97.0%), respectively. Four patients with multiple cardiovascular risk factors experienced delayed G3 cardiac events. The cumulative incidence of second malignancies at 20 years was 6.1%. Fertility and childbearing potential were unaffected. Data support an ongoing benefit for ABVDDD-DI without uneven late toxicities.

12.
Ann Hematol ; 2024 Sep 12.
Article in English | MEDLINE | ID: mdl-39264432

ABSTRACT

Most patients with Primary Mediastinal B-Cell Lymphoma (PMBCL) are cured by rituximab and doxorubicin-based immunochemotherapy, with or without radiotherapy. In cases with relapsed and refractory (RR) disease the prognosis was historically poor. Recently, immune checkpoint-based strategies have been shown to be highly effective in patients with RR-PMBCL. We report the case of a 23-year-old woman who, due to recurring episodes of symptomatic chemotherapy-induced sinus bradycardia, was unable to receive the planned six courses of immunochemotherapy, mediastinal radiotherapy, and autologous transplantation, leading to the early initiation of a chemo-free strategy. The patient maintains a continuous complete remission at a four-year follow-up after only two cycles of immunochemotherapy followed by nivolumab plus brentuximab vedotin (BV) and pembrolizumab consolidation. Beyond describing an underreported complication of anticancer treatments, the favorable clinical outcome suggests that in PMBCL, a minimal load of chemotherapy, integrated by early PD-1 blockade, with or without BV, may be sufficient to achieve long-term disease control and cure at least in some patients.

13.
Int J Mol Sci ; 25(3)2024 Jan 25.
Article in English | MEDLINE | ID: mdl-38338733

ABSTRACT

Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare and aggressive hematologic cancer originating from the malignant transformation of plasmacytoid dendritic cell precursors. This malignancy progresses rapidly, with frequent relapses and a poor overall survival rate, underscoring the urgent need for effective treatments. However, diagnosing and treating BPDCN have historically been challenging due to its rarity and the lack of standardized approaches. The recognition of BPDCN as a distinct disease entity is recent, and standardized treatment protocols are yet to be established. Traditionally, conventional chemotherapy and stem cell transplantation have been the primary methods for treating BPDCN patients. Advances in immunophenotyping and molecular profiling have identified potential therapeutic targets, leading to a shift toward CD123-targeted immunotherapies in both clinical and research settings. Ongoing developments with SL-401, IMGN632, CD123 chimeric antigen receptor (CAR) T-cells, and bispecific antibodies (BsAb) show promising advancements. However, the therapeutic effectiveness of CD123-targeting treatments needs improvement through innovative approaches and combinations of treatments with other anti-leukemic drugs. The exploration of combinations such as CD123-targeted immunotherapies with azacitidine and venetoclax is suggested to enhance antineoplastic responses and improve survival rates in BPDCN patients. In conclusion, this multifaceted approach offers hope for more effective and tailored therapeutic interventions against this challenging hematologic malignancy.


Subject(s)
Hematologic Neoplasms , Interleukin-3 Receptor alpha Subunit , Myeloproliferative Disorders , Humans , Dendritic Cells , Hematologic Neoplasms/drug therapy , Hematologic Neoplasms/pathology , Interleukin-3 Receptor alpha Subunit/drug effects , Myeloproliferative Disorders/drug therapy , Myeloproliferative Disorders/pathology , Neoplasm Recurrence, Local/pathology , Skin Neoplasms/drug therapy , Skin Neoplasms/pathology , Stem Cell Transplantation
14.
Int J Mol Sci ; 25(14)2024 Jul 09.
Article in English | MEDLINE | ID: mdl-39062753

ABSTRACT

Dendritic cell (DC) cancer vaccines are a promising therapeutic approach, leveraging the immune system to fight tumors. These vaccines utilize DCs' ability to present tumor-associated antigens to T cells, triggering a robust immune response. DC vaccine development has progressed through three generations. The first generation involved priming DCs with tumor-associated antigens or messenger RNA outside the body, showing limited clinical success. The second generation improved efficacy by using cytokine mixtures and specialized DC subsets to enhance immunogenicity. The third generation used blood-derived DCs to elicit a stronger immune response. Clinical trials indicate that cancer vaccines have lower toxicity than traditional cytotoxic treatments. However, achieving significant clinical responses with DC immunotherapy remains challenging. Combining DC vaccines with immune checkpoint inhibitors (ICIs), such as anticytotoxic T-lymphocyte Antigen 4 and antiprogrammed death-1 antibodies, has shown promise by enhancing T-cell responses and improving clinical outcomes. These combinations can transform non-inflamed tumors into inflamed ones, boosting ICIs' efficacy. Current research is exploring new checkpoint targets like LAG-3, TIM-3, and TIGIT, considering their potential with DC vaccines. Additionally, engineering T cells with chimeric antigen receptors or T-cell receptors could further augment the antitumor response. This comprehensive strategy aims to enhance cancer immunotherapy, focusing on increased efficacy and improved patient survival rates.


Subject(s)
Cancer Vaccines , Dendritic Cells , Immune Checkpoint Inhibitors , Neoplasms , Dendritic Cells/immunology , Humans , Immune Checkpoint Inhibitors/therapeutic use , Immune Checkpoint Inhibitors/pharmacology , Cancer Vaccines/immunology , Cancer Vaccines/therapeutic use , Neoplasms/therapy , Neoplasms/immunology , Neoplasms/drug therapy , Combined Modality Therapy , Animals , Immunotherapy/methods , Vaccination/methods
15.
J Transl Med ; 21(1): 318, 2023 05 11.
Article in English | MEDLINE | ID: mdl-37170241

ABSTRACT

BACKGROUND: Nivolumab is an anti-PD1 antibody that has dramatically improved metastatic melanoma patients' outcomes. Nevertheless, many patients are resistant to PD-1 inhibition, occasionally experiencing severe off-target immune toxicity. In addition, no robust and reproducible biomarkers have yet been validated to identify the correct selection of patients who will benefit from anti-PD-1 treatment avoiding unwanted side effects. However, the strength of CD26 expression on CD4+ T lymphocytes permits the characterization of three subtypes with variable degrees of responsiveness to tumors, suggesting that the presence of CD26-expressing T cells in patients might be a marker of responsiveness to PD-1-based therapies. METHODS: The frequency distribution of peripheral blood CD26-expressing cells was investigated employing multi-parametric flow cytometry in 69 metastatic melanoma patients along with clinical characteristics and blood count parameters at baseline (W0) and compared to 20 age- and sex-matched healthy controls. Percentages of baseline CD4+CD26high T cells were correlated with the outcome after nivolumab treatment. In addition, the frequency of CD4+CD26high T cells at W0 was compared with those obtained after 12 weeks (W1) of therapy in a sub-cohort of 33 patients. RESULTS: Circulating CD4+CD26high T cells were significantly reduced in melanoma patients compared to healthy subjects (p = 0.001). In addition, a significant association was observed between a low baseline percentage of CD4+CD26high T cells (< 7.3%) and clinical outcomes, measured as overall survival (p = 0.010) and progression-free survival (p = 0.014). Moreover, patients with clinical benefit from nivolumab therapy had significantly higher frequencies of circulating CD4+CD26high T cells than patients with non-clinical benefit (p = 0.004) at 12 months. Also, a higher pre-treatment proportion of circulating CD4+CD26high T cells was correlated with Disease Control Rate (p = 0.014) and best Overall Response Rate (p = 0.009) at 12 months. Interestingly, after 12 weeks (W1) of nivolumab treatment, percentages of CD4+CD26high T cells were significantly higher in comparison with the frequencies measured at W0 (p < 0.0001), aligning the cell counts with the ranges seen in the blood of healthy subjects. CONCLUSIONS: Our study firstly demonstrates that peripheral blood circulating CD4+CD26high T lymphocytes represent potential biomarkers whose perturbations are associated with reduced survival and worse clinical outcomes in melanoma patients.


Subject(s)
Melanoma , Nivolumab , Humans , Nivolumab/pharmacology , Nivolumab/therapeutic use , T-Lymphocytes , Dipeptidyl Peptidase 4/therapeutic use , Melanoma/pathology , Progression-Free Survival
16.
Blood ; 137(5): 637-645, 2021 02 04.
Article in English | MEDLINE | ID: mdl-32870269

ABSTRACT

Nivolumab, an anti-programmed death-1 (PD-1) monoclonal antibody, showed promising activity in relapsed or refractory (R/R) follicular lymphoma (FL) in a phase 1 study. We conducted a phase 2 trial to further evaluate its efficacy and safety in patients with R/R FL and to explore biomarkers of response. Patients with R/R FL and at least 2 prior lines of therapy, each containing a CD20 antibody or an alkylating agent, were treated with nivolumab 3 mg/kg every 2 weeks. The primary end point was objective response rate (ORR) assessed by an independent radiologic review committee. Biomarker analyses included gene expression profiling and multiplex immunofluorescence studies of pretreatment tumor samples. A total of 92 patients were treated. After a minimum follow-up of 12 months, ORR was 4% (4 of 92 patients). Median progression-free survival (PFS) was 2.2 months (95% confidence interval [CI], 1.9-3.6 months). Median duration of response was 11 months (95% CI, 8-14 months). Exploratory analyses suggested that responders had significantly higher proportion of CD3+ T cells in the tumor microenvironment than nonresponders, but no significant differences in PD-1 or programmed death-ligand 1 expression were observed. High expression of a set of tumor-associated macrophage genes was associated with reduced PFS (hazard ratio, 3.28; 95% CI, 1.76-6.11; P = .001). The safety profile was consistent with previous reports of nivolumab. In conclusion, nivolumab monotherapy was associated with very limited activity in patients with R/R FL. Better understanding of the immune biology of this disease may facilitate the development of effective checkpoint-based strategies. This trial was registered at www.clinicaltrials.gov as #NCT02038946.


Subject(s)
Antineoplastic Agents, Immunological/therapeutic use , Lymphoma, Follicular/drug therapy , Nivolumab/therapeutic use , Salvage Therapy , Adult , Aged , Antineoplastic Agents, Alkylating/administration & dosage , Antineoplastic Agents, Immunological/adverse effects , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Biomarkers, Tumor , Female , Follow-Up Studies , Gene Expression Profiling , Humans , Kaplan-Meier Estimate , Lymphoma, Follicular/diagnostic imaging , Male , Middle Aged , Neoplasm Proteins/antagonists & inhibitors , Nivolumab/adverse effects , Programmed Cell Death 1 Receptor/antagonists & inhibitors , Progression-Free Survival , Recurrence , Rituximab/administration & dosage , Tumor Microenvironment
17.
Proc Natl Acad Sci U S A ; 117(22): 11865-11874, 2020 06 02.
Article in English | MEDLINE | ID: mdl-32444484

ABSTRACT

Striated muscle contraction involves sliding of actin thin filaments along myosin thick filaments, controlled by calcium through thin filament activation. In relaxed muscle, the two heads of myosin interact with each other on the filament surface to form the interacting-heads motif (IHM). A key question is how both heads are released from the surface to approach actin and produce force. We used time-resolved synchrotron X-ray diffraction to study tarantula muscle before and after tetani. The patterns showed that the IHM is present in live relaxed muscle. Tetanic contraction produced only a very small backbone elongation, implying that mechanosensing-proposed in vertebrate muscle-is not of primary importance in tarantula. Rather, thick filament activation results from increases in myosin phosphorylation that release a fraction of heads to produce force, with the remainder staying in the ordered IHM configuration. After the tetanus, the released heads slowly recover toward the resting, helically ordered state. During this time the released heads remain close to actin and can quickly rebind, enhancing the force produced by posttetanic twitches, structurally explaining posttetanic potentiation. Taken together, these results suggest that, in addition to stretch activation in insects, two other mechanisms for thick filament activation have evolved to disrupt the interactions that establish the relaxed helices of IHMs: one in invertebrates, by either regulatory light-chain phosphorylation (as in arthropods) or Ca2+-binding (in mollusks, lacking phosphorylation), and another in vertebrates, by mechanosensing.


Subject(s)
Muscle, Striated/physiology , Myosins/metabolism , Phosphorylation/physiology , Actin Cytoskeleton/chemistry , Actin Cytoskeleton/metabolism , Animals , Arthropods/physiology , Evolution, Molecular , Invertebrates/physiology , Models, Molecular , Muscle Contraction , Muscle Relaxation , Myosins/chemistry , Protein Structure, Secondary , Spiders/physiology , Vertebrates/physiology
18.
Sensors (Basel) ; 23(2)2023 Jan 12.
Article in English | MEDLINE | ID: mdl-36679712

ABSTRACT

The sharing of cyberthreat information within a community or group of entities is possible due to solutions such as the Malware Information Sharing Platform (MISP). However, the MISP was considered limited if its information was deemed as classified or shared only for a given period of time. A solution using searchable encryption techniques that better control the sharing of information was previously proposed by the same authors. This paper describes a prototype implementation for two key functionalities of the previous solution, considering multiple entities sharing information with each other: the symmetric key generation of a sharing group and the functionality to update a shared index. Moreover, these functionalities are evaluated regarding their performance, and enhancements are proposed to improve the performance of the implementation regarding its execution time. As the main result, the duration of the update process was shortened from around 2922 s to around 302 s, when considering a shared index with 100,000 elements. From the security analysis performed, the implementation can be considered secure, thus confirming the secrecy of the exchanged nonces. The limitations of the current implementation are depicted, and future work is pointed out.


Subject(s)
Algorithms , Computer Security , Confidentiality , Information Dissemination
19.
Radiol Med ; 128(2): 222-233, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36658367

ABSTRACT

OBJECTIVES: To develop a structured reporting (SR) template for whole-body CT examinations of polytrauma patients, based on the consensus of a panel of emergency radiology experts from the Italian Society of Medical and Interventional Radiology. METHODS: A multi-round Delphi method was used to quantify inter-panelist agreement for all SR sections. Internal consistency for each section and quality analysis in terms of average inter-item correlation were evaluated by means of the Cronbach's alpha (Cα) correlation coefficient. RESULTS: The final SR form included 118 items (6 in the "Patient Clinical Data" section, 4 in the "Clinical Evaluation" section, 9 in the "Imaging Protocol" section, and 99 in the "Report" section). The experts' overall mean score and sum of scores were 4.77 (range 1-5) and 257.56 (range 206-270) in the first Delphi round, and 4.96 (range 4-5) and 208.44 (range 200-210) in the second round, respectively. In the second Delphi round, the experts' overall mean score was higher than in the first round, and standard deviation was lower (3.11 in the second round vs 19.71 in the first round), reflecting a higher expert agreement in the second round. Moreover, Cα was higher in the second round than in the first round (0.97 vs 0.87). CONCLUSIONS: Our SR template for whole-body CT examinations of polytrauma patients is based on a strong agreement among panel experts in emergency radiology and could improve communication between radiologists and the trauma team.


Subject(s)
Multiple Trauma , Radiology , Humans , Delphi Technique , Consensus , Tomography, X-Ray Computed
20.
Blood ; 135(13): 996-1007, 2020 03 26.
Article in English | MEDLINE | ID: mdl-31977002

ABSTRACT

Treatment options for relapsed/refractory (R/R) diffuse large B-cell lymphoma (DLBCL) are limited, with no standard of care; prognosis is poor, with 4- to 6-month median survival. Avadomide (CC-122) is a cereblon-modulating agent with immunomodulatory and direct antitumor activities. This phase 1 dose-expansion study assessed safety and clinical activity of avadomide monotherapy in patients with de novo R/R DLBCL and transformed lymphoma. Additionally, a novel gene expression classifier, which identifies tumors with a high immune cell infiltration, was shown to enrich for response to avadomide in R/R DLBCL. Ninety-seven patients with R/R DLBCL, including 12 patients with transformed lymphoma, received 3 to 5 mg avadomide administered on continuous or intermittent schedules until unacceptable toxicity, disease progression, or withdrawal. Eighty-two patients (85%) experienced ≥1 grade 3/4 treatment-emergent adverse events (AEs), most commonly neutropenia (51%), infections (24%), anemia (12%), and febrile neutropenia (10%). Discontinuations because of AEs occurred in 10% of patients. Introduction of an intermittent 5/7-day schedule improved tolerability and reduced frequency and severity of neutropenia, febrile neutropenia, and infections. Among 84 patients with de novo R/R DLBCL, overall response rate (ORR) was 29%, including 11% complete response (CR). Responses were cell-of-origin independent. Classifier-positive DLBCL patients (de novo) had an ORR of 44%, median progression-free survival (mPFS) of 6 months, and 16% CR vs an ORR of 19%, mPFS of 1.5 months, and 5% CR in classifier-negative patients (P = .0096). Avadomide is being evaluated in combination with other antilymphoma agents. This trial was registered at www.clinicaltrials.gov as #NCT01421524.


Subject(s)
Antineoplastic Agents/therapeutic use , Lymphoma, Large B-Cell, Diffuse/drug therapy , Lymphoma, Large B-Cell, Diffuse/pathology , Piperidones/therapeutic use , Quinazolinones/therapeutic use , Adult , Aged , Aged, 80 and over , Antineoplastic Agents/administration & dosage , Antineoplastic Agents/adverse effects , Antineoplastic Agents/pharmacokinetics , Biomarkers , Drug Resistance, Neoplasm , Female , Humans , Immunophenotyping , Lymphoma, Large B-Cell, Diffuse/genetics , Lymphoma, Large B-Cell, Diffuse/mortality , Macrophages/immunology , Macrophages/metabolism , Macrophages/pathology , Male , Middle Aged , Neoplasm Staging , Odds Ratio , Piperidones/administration & dosage , Piperidones/adverse effects , Piperidones/pharmacokinetics , Prognosis , Quinazolinones/administration & dosage , Quinazolinones/adverse effects , Quinazolinones/pharmacokinetics , Recurrence , Retreatment , T-Lymphocytes/immunology , T-Lymphocytes/metabolism , Treatment Outcome
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