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1.
J Clin Invest ; 134(10)2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38530357

RESUMO

Despite widespread utilization of immunotherapy, treating immune-cold tumors remains a challenge. Multiomic analyses and experimental validation identified the OTUD4/CD73 proteolytic axis as a promising target in treating immune-suppressive triple negative breast cancer (TNBC). Mechanistically, deubiquitylation of CD73 by OTUD4 counteracted its ubiquitylation by TRIM21, resulting in CD73 stabilization inhibiting tumor immune responses. We further demonstrated the importance of TGF-ß signaling for orchestrating the OTUD4/CD73 proteolytic axis within tumor cells. Spatial transcriptomics profiling discovered spatially resolved features of interacting malignant and immune cells pertaining to expression levels of OTUD4 and CD73. In addition, ST80, a newly developed inhibitor, specifically disrupted proteolytic interaction between CD73 and OTUD4, leading to reinvigoration of cytotoxic CD8+ T cell activities. In preclinical models of TNBC, ST80 treatment sensitized refractory tumors to anti-PD-L1 therapy. Collectively, our findings uncover what we believe to be a novel strategy for targeting the immunosuppressive OTUD4/CD73 proteolytic axis in treating immune-suppressive breast cancers with the inhibitor ST80.


Assuntos
5'-Nucleotidase , Proteólise , Neoplasias de Mama Triplo Negativas , Animais , Feminino , Humanos , Camundongos , 5'-Nucleotidase/genética , 5'-Nucleotidase/imunologia , 5'-Nucleotidase/antagonistas & inibidores , Linhagem Celular Tumoral , Proteínas Ligadas por GPI/imunologia , Proteínas Ligadas por GPI/genética , Proteínas Ligadas por GPI/metabolismo , Proteínas Ligadas por GPI/antagonistas & inibidores , Proteínas de Neoplasias/imunologia , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Proteínas de Neoplasias/antagonistas & inibidores , Neoplasias de Mama Triplo Negativas/imunologia , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/patologia , Ubiquitinação , Proteases Específicas de Ubiquitina
2.
bioRxiv ; 2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-38352441

RESUMO

Obesity is a major public health crisis given its rampant growth and association with an increased risk for cancer. Interestingly, patients with obesity tend to have an increased tumor burden and decreased T-cell function. It remains unclear how obesity compromises T-cell mediated immunity. To address this question, we modeled the adipocyte niche using the secretome released from adipocytes as well as the niche of stromal cells and investigated how these factors modulated T-cell function. We found that the secretomes altered antigen-specific T-cell receptor (TCR) triggering and activation. RNA-sequencing analysis identified thousands of gene targets modulated by the secretome including those associated with cytoskeletal regulation and actin polymerization. We next used molecular force probes to show that T-cells exposed to the adipocyte niche display dampened force transmission to the TCR-antigen complex and conversely, stromal cell secreted factors lead to significantly enhanced TCR forces. These results were then validated in diet-induced obese mice. Importantly, secretome-mediated TCR force modulation mirrored the changes in T-cell functional responses in human T-cells using the FDA-approved immunotherapy, blinatumomab. Thus, this work shows that the adipocyte niche contributes to T-cell dysfunction through cytoskeletal modulation and reduces TCR triggering by dampening TCR forces consistent with the mechanosensor model of T-cell activation.

3.
Blood ; 142(23): 1972-1984, 2023 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-37624902

RESUMO

Hemophagocytic lymphohistiocytosis (HLH) is characterized by hyperinflammation and multiorgan dysfunction. Infections, including the reactivation of viruses, contribute to significant disease mortality in HLH. Although T-cell and natural killer cell-driven immune activation and dysregulation are well described, limited data exist on the status of B-cell compartment and humoral immune function in HLH. We noted marked suppression of early B-cell development in patients with active HLH. In vitro B-cell differentiation studies after exposure to HLH-defining cytokines, such as interferon gamma (IFN-γ) and tumor necrosis factor, recapitulated B-cell development arrest. Messenger RNA sequencing of human CD34+ cells exposed to IFN-γ demonstrated changes in genes and pathways affecting B-cell development and maturation. In addition, patients with active HLH exhibited a marked decrease in class-switched memory B (CSMB) cells and a decrease in bone marrow plasmablast/plasma cell compartments. The decrease in CSMB cells was associated with a decrease in circulating T follicular helper (cTfh) cells. Finally, lymph node and spleen evaluation in a patient with HLH revealed absent germinal center formation and hemophagocytosis with associated lymphopenia. Reassuringly, the frequency of CSMB and cTfh improved with the control of T-cell activation. Taken together, in patients with active HLH, these changes in B cells may affect the humoral immune response; however, further immune studies are needed to determine its clinical significance.


Assuntos
Linfo-Histiocitose Hemofagocítica , Humanos , Linfo-Histiocitose Hemofagocítica/patologia , Citocinas/metabolismo , Interferon gama/genética , Linfócitos T , Células Matadoras Naturais
4.
Cancer Res Commun ; 3(7): 1248-1259, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37465593

RESUMO

Siglec-15 (Sig15) has been implicated as an immune checkpoint expressed in solid tumor-infiltrating macrophages and is being targeted in clinical trials with mAbs to normalize the tumor immune microenvironment and stimulate antitumor immunity. However, the role of Sig15 in hematologic malignancies remains undefined. Sig15 mRNA and protein expression levels in hematologic malignancies were determined from publicly available databases, cell lines, and primary patient samples. Human B-cell acute lymphoblastic leukemia (B-ALL) cell lines were used to identify signaling pathways involved in the regulation of Sig15 expression. Secreted/soluble Sig15 and cytokine levels were measured from the plasma of children with leukemia and healthy controls. Knockdown and knockout of Siglec15 in a murine model of B-ALL was used to evaluate the effect of leukemia-derived Sig15 on the immune response to leukemia. We observed pathologic overexpression of Sig15 in a variety of hematologic malignancies, including primary B-ALL samples. This overexpression was driven by NFκB activation, which also increased the surface localization of Sig15. Secreted/soluble Sig15 was found to circulate at elevated levels in the plasma of children with B-ALL and correlated with an immune-suppressive cytokine milieu. Genetic inhibition of Sig15 in murine B-ALL promoted clearance of the leukemia by the immune system and a marked reversal of the immune-privileged leukemia bone marrow niche, including expanded early effector CD8+ T cells and reduction of immunosuppressive cytokines. Thus, Sig15 is a novel, potent immunosuppressive molecule active in leukemia that may be targeted therapeutically to activate T lymphocytes against leukemia cells. Significance: We demonstrate that Sig15 is overexpressed in hematologic malignancies driven by NFκB, is required for immune evasion in a mouse model of leukemia, and, for the first time, that it circulates at high levels in the plasma of children with leukemia.


Assuntos
Linfoma de Burkitt , Neoplasias Hematológicas , Leucemia , Leucemia-Linfoma Linfoblástico de Células Precursoras B , Animais , Criança , Humanos , Camundongos , Imunidade Adaptativa , Linfócitos T CD8-Positivos , Citocinas , Imunoglobulinas , Proteínas de Membrana , Leucemia-Linfoma Linfoblástico de Células Precursoras B/genética , Lectinas Semelhantes a Imunoglobulina de Ligação ao Ácido Siálico , Microambiente Tumoral/genética
6.
Pediatr Blood Cancer ; 70(8): e30405, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37158620

RESUMO

BACKGROUND: 3-Hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase inhibitors (statins) can inhibit tumor proliferation, angiogenesis, and restore apoptosis in preclinical pediatric solid tumor models. We conducted a phase 1 trial to determine the maximum tolerated dose (MTD) of simvastatin with topotecan and cyclophosphamide in children with relapsed/refractory solid and central nervous system (CNS) tumors. METHODS: Simvastatin was administered orally twice daily on days 1-21, with topotecan and cyclophosphamide intravenously on days 1-5 of a 21-day cycle. Four simvastatin dose levels (DLs) were planned, 140 (DL1), 180 (DL2), 225 (DL3), 290 (DL4) mg/m2 /dose, with a de-escalation DL of 100 mg/m2 /dose (DL0) if needed. Pharmacokinetic and pharmacodynamic analyses were performed during cycle 1. RESULTS: The median age of 14 eligible patients was 11.5 years (range: 1-23). The most common diagnoses were neuroblastoma (N = 4) and Ewing sarcoma (N = 3). Eleven dose-limiting toxicity (DLT)-evaluable patients received a median of four cycles (range: 1-6). There were three cycle 1 DLTs: one each grade 3 diarrhea and grade 4 creatine phosphokinase (CPK) elevations at DL1, and one grade 4 CPK elevation at DL0. All patients experienced at least one grade 3/4 hematologic toxicity. Best overall response was partial response in one patient with Ewing sarcoma (DL0) and stable disease for four or more cycles in four patients. Simvastatin exposure increased with higher doses and may have correlated with toxicity. Plasma interleukin 6 (IL-6) concentrations (N = 6) showed sustained IL-6 reductions with decrease to normal values by day 21 in all patients, indicating potential on-target effects. CONCLUSIONS: The MTD of simvastatin with topotecan and cyclophosphamide was determined to be 100 mg/m2 /dose.


Assuntos
Neoplasias do Sistema Nervoso Central , Neoplasias , Tumores Neuroectodérmicos Primitivos Periféricos , Sarcoma de Ewing , Humanos , Criança , Lactente , Pré-Escolar , Adolescente , Adulto Jovem , Adulto , Topotecan , Sinvastatina/efeitos adversos , Interleucina-6 , Ciclofosfamida , Neoplasias/tratamento farmacológico , Neoplasias do Sistema Nervoso Central/tratamento farmacológico , Neoplasias do Sistema Nervoso Central/etiologia , Dose Máxima Tolerável , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos
7.
J Natl Cancer Inst Monogr ; 2023(61): 12-29, 2023 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-37139973

RESUMO

The obesity pandemic currently affects more than 70 million Americans and more than 650 million individuals worldwide. In addition to increasing susceptibility to pathogenic infections (eg, SARS-CoV-2), obesity promotes the development of many cancer subtypes and increases mortality rates in most cases. We and others have demonstrated that, in the context of B-cell acute lymphoblastic leukemia (B-ALL), adipocytes promote multidrug chemoresistance. Furthermore, others have demonstrated that B-ALL cells exposed to the adipocyte secretome alter their metabolic states to circumvent chemotherapy-mediated cytotoxicity. To better understand how adipocytes impact the function of human B-ALL cells, we used a multi-omic RNA-sequencing (single-cell and bulk transcriptomic) and mass spectroscopy (metabolomic and proteomic) approaches to define adipocyte-induced changes in normal and malignant B cells. These analyses revealed that the adipocyte secretome directly modulates programs in human B-ALL cells associated with metabolism, protection from oxidative stress, increased survival, B-cell development, and drivers of chemoresistance. Single-cell RNA sequencing analysis of mice on low- and high-fat diets revealed that obesity suppresses an immunologically active B-cell subpopulation and that the loss of this transcriptomic signature in patients with B-ALL is associated with poor survival outcomes. Analyses of sera and plasma samples from healthy donors and those with B-ALL revealed that obesity is associated with higher circulating levels of immunoglobulin-associated proteins, which support observations in obese mice of altered immunological homeostasis. In all, our multi-omics approach increases our understanding of pathways that may promote chemoresistance in human B-ALL and highlight a novel B-cell-specific signature in patients associated with survival outcomes.


Assuntos
COVID-19 , Leucemia-Linfoma Linfoblástico de Células Precursoras , Humanos , Animais , Camundongos , Proteômica , SARS-CoV-2 , Obesidade/complicações , Obesidade/metabolismo
8.
Biomacromolecules ; 24(3): 1164-1172, 2023 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-36745712

RESUMO

Cytokines act as potent, extracellular signals of the human immune system and can elicit striking treatment responses in patients with autoimmune disease, tissue damage, and cancer. Yet, despite their therapeutic potential, recombinant cytokine-mediated immune responses remain difficult to control as their administration is often systemic, whereas their intended sites of action are localized. To address the challenge of spatially and temporally constraining cytokine signals, we recently devised a strategy whereby recombinant cytokines are reversibly inactivated via chemical modification with photo-labile polymers that respond to visible LED light. Extending this approach to enable both in vivo and multicolor immune activation, here we describe a strategy whereby cytokines appended with heptamethine cyanine-polyethylene glycol are selectively re-activated ex vivo using tissue-penetrating near-infrared (NIR) light. We show that NIR LED light illumination of caged, pro-inflammatory cytokines restores cognate receptor signaling and potentiates the activity of T cell-engager cancer immunotherapies ex vivo. Using combinations of visible- and NIR-responsive cytokines, we further demonstrate multiwavelength optical control of T cell cytolysis ex vivo, as well as the ability to perform Boolean logic using multicolored light and orthogonally photocaged cytokine pairs as inputs and T cell activity as outputs. Together, this work demonstrates a novel approach to control extracellular immune cell signals using light, a strategy that in the future may improve our understanding of and ability to treat cancer and other diseases.


Assuntos
Citocinas , Neoplasias , Humanos , Polímeros , Fatores Imunológicos , Polietilenoglicóis
9.
Front Cell Dev Biol ; 10: 909557, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36060800

RESUMO

The world's population with obesity is reaching pandemic levels. If current trends continue, it is predicted that there will be 1.5 billion people with obesity by 2030. This projection is alarming due to the association of obesity with numerous diseases including cancer, with recent studies demonstrating a positive association with acute myeloid leukemia (AML) and B cell acute lymphoblastic leukemia (B-ALL). Interestingly, several epidemiological studies suggest the converse relationship may exist in patients with T cell acute lymphoblastic leukemia (T-ALL). To determine the relationship between obesity and T-ALL development, we employed the diet-induced obesity (DIO) murine model and cultured human T-ALL cells in adipocyte-conditioned media (ACM), bone marrow stromal cell-conditioned media, stromal conditioned media (SCM), and unconditioned media to determine the functional impact of increased adiposity on leukemia progression. Whereas only 20% of lean mice transplanted with T-ALL cells survived longer than 3 months post-inoculation, 50%-80% of obese mice with leukemia survived over this same period. Furthermore, culturing human T-ALL cells in ACM resulted in increased histone H3 acetylation (K9/K14/K18/K23/K27) and methylation (K4me3 and K27me3) posttranslational modifications (PTMs), which preceded accelerated cell cycle progression, DNA damage, and cell death. Adipocyte-mediated epigenetic changes in human T-ALL cells were recapitulated with the H3K27 demethylase inhibitor GSK-J4 and the pan-HDAC inhibitor vorinostat. These drugs were also highly cytotoxic to human T-ALL cells at low micromolar concentrations. In summary, our data support epidemiological studies demonstrating that adiposity suppresses T-ALL pathogenesis. We present data demonstrating that T-ALL cell death in adipose-rich microenvironments is induced by epigenetic modifications, which are not tolerated by leukemia cells. Similarly, GSK-J4 and vorinostat treatment induced epigenomic instability and cytotoxicity profiles that phenocopied the responses of human T-ALL cells to ACM, which provides additional support for the use of epigenetic modifying drugs as a treatment option for T-ALL.

10.
Exp Hematol ; 112-113: 24-34, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35803545

RESUMO

Germline mutations in ETV6 are associated with a syndrome of thrombocytopenia and leukemia predisposition, and ETV6 is among the most commonly mutated genes in leukemias, especially childhood B-cell acute lymphoblastic leukemia. However, the mechanisms underlying disease caused by ETV6 dysfunction are poorly understood. To address these gaps in knowledge, using CRISPR/Cas9, we developed a mouse model of the most common recurrent, disease-causing germline mutation in ETV6. We found defects in hematopoiesis related primarily to abnormalities of the multipotent progenitor population 4 (MPP4) subset of hematopoietic progenitor cells and evidence of sterile inflammation. Expression of ETV6 in Ba/F3 cells altered the expression of several cytokines, some of which were also detected at higher levels in the bone marrow of the mice with Etv6 mutation. Among these, interleukin-18 and interleukin-13 abrogated B-cell development of sorted MPP4 cells, but not common lymphoid progenitors, suggesting that inflammation contributes to abnormal hematopoiesis by impairing lymphoid development. These data, along with those from humans, support a model in which ETV6 dysfunction promotes inflammation, which adversely affects thrombopoiesis and promotes leukemogenesis.


Assuntos
Mutação em Linhagem Germinativa , Leucemia-Linfoma Linfoblástico de Células Precursoras , Proteínas Proto-Oncogênicas c-ets , Animais , Células Germinativas/metabolismo , Humanos , Inflamação/genética , Camundongos , Mutação , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Proteínas Proto-Oncogênicas c-ets/genética , Proteínas Repressoras/genética , Trombopoese , Variante 6 da Proteína do Fator de Translocação ETS
11.
Sci Rep ; 12(1): 11870, 2022 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-35831470

RESUMO

Immunotherapies have revolutionized the treatment of B-cell acute lymphoblastic leukemia (B-ALL), but the duration of responses is still sub-optimal. We sought to identify mechanisms of immune suppression in B-ALL and strategies to overcome them. Plasma collected from children with B-ALL with measurable residual disease after induction chemotherapy showed differential cytokine expression, particularly IL-7, while single-cell RNA-sequencing revealed the expression of genes associated with immune exhaustion in immune cell subsets. We also found that the supernatant of leukemia cells suppressed T-cell function ex vivo. Modeling B-ALL in mice, we observed an altered tumor immune microenvironment, including compromised activation of T-cells and dendritic cells (DC). However, recombinant IL-12 (rIL-12) treatment of mice with B-ALL restored the levels of several pro-inflammatory cytokines and chemokines in the bone marrow and increased the number of splenic and bone marrow resident T-cells and DCs. RNA-sequencing of T-cells isolated from vehicle and rIL-12 treated mice with B-ALL revealed that the leukemia-induced increase in genes associated with exhaustion, including Lag3, Tigit, and Il10, was abrogated with rIL-12 treatment. In addition, the cytolytic capacity of T-cells co-cultured with B-ALL cells was enhanced when IL-12 and blinatumomab treatments were combined. Overall, these results demonstrate that the leukemia immune suppressive microenvironment can be restored with rIL-12 treatment which has direct therapeutic implications.


Assuntos
Interleucina-12 , Leucemia-Linfoma Linfoblástico de Células Precursoras , Animais , Medula Óssea/metabolismo , Citocinas/metabolismo , Células Dendríticas , Interleucina-12/genética , Interleucina-12/metabolismo , Camundongos , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , RNA/metabolismo , Microambiente Tumoral
12.
Nat Commun ; 13(1): 1157, 2022 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-35241678

RESUMO

The incidence of obesity is rising with greater than 40% of the world's population expected to be overweight or suffering from obesity by 2030. This is alarming because obesity increases mortality rates in patients with various cancer subtypes including leukemia. The survival differences between lean patients and patients with obesity are largely attributed to altered drug pharmacokinetics in patients receiving chemotherapy; whereas, the direct impact of an adipocyte-enriched microenvironment on cancer cells is rarely considered. Here we show that the adipocyte secretome upregulates the surface expression of Galectin-9 (GAL-9) on human B-acute lymphoblastic leukemia cells (B-ALL) which promotes chemoresistance. Antibody-mediated targeting of GAL-9 on B-ALL cells induces DNA damage, alters cell cycle progression, and promotes apoptosis in vitro and significantly extends the survival of obese but not lean mice with aggressive B-ALL. Our studies reveal that adipocyte-mediated upregulation of GAL-9 on B-ALL cells can be targeted with antibody-based therapies to overcome obesity-induced chemoresistance.


Assuntos
Linfoma de Burkitt , Galectinas , Obesidade , Leucemia-Linfoma Linfoblástico de Células Precursoras , Animais , Apoptose , Linfoma de Burkitt/tratamento farmacológico , Linfoma de Burkitt/metabolismo , Linfoma de Burkitt/patologia , Linhagem Celular Tumoral , Galectinas/metabolismo , Humanos , Camundongos , Obesidade/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Microambiente Tumoral/fisiologia
13.
Aging Cell ; 20(2): e13309, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33480151

RESUMO

Aging-associated declines in innate and adaptive immune responses are well documented and pose a risk for the growing aging population, which is predicted to comprise greater than 40 percent of the world's population by 2050. Efforts have been made to improve immunity in aged populations; however, safe and effective protocols to accomplish this goal have not been universally established. Aging-associated chronic inflammation is postulated to compromise immunity in aged mice and humans. Interleukin-37 (IL-37) is a potent anti-inflammatory cytokine, and we present data demonstrating that IL-37 gene expression levels in human monocytes significantly decline with age. Furthermore, we demonstrate that transgenic expression of interleukin-37 (IL-37) in aged mice reduces or prevents aging-associated chronic inflammation, splenomegaly, and accumulation of myeloid cells (macrophages and dendritic cells) in the bone marrow and spleen. Additionally, we show that IL-37 expression decreases the surface expression of programmed cell death protein 1 (PD-1) and augments cytokine production from aged T-cells. Improved T-cell function coincided with a youthful restoration of Pdcd1, Lat, and Stat4 gene expression levels in CD4+ T-cells and Lat in CD8+ T-cells when aged mice were treated with recombinant IL-37 (rIL-37) but not control immunoglobin (Control Ig). Importantly, IL-37-mediated rejuvenation of aged endogenous T-cells was also observed in aged chimeric antigen receptor (CAR) T-cells, where improved function significantly extended the survival of mice transplanted with leukemia cells. Collectively, these data demonstrate the potency of IL-37 in boosting the function of aged T-cells and highlight its therapeutic potential to overcome aging-associated immunosenescence.


Assuntos
Envelhecimento , Terapia Baseada em Transplante de Células e Tecidos , Interleucina-1/imunologia , Receptores de Antígenos Quiméricos/imunologia , Animais , Linhagem Celular , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Transgênicos
14.
Trop Med Infect Dis ; 7(1)2021 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-35051117

RESUMO

The objective of this pilot malacological survey was to identify the snail intermediate hosts for Schistosoma haematobium in endemic rural and semi-urban areas of Gabon. Snails were collected, morphologically identified, and tested for infection by cercarial shedding. Released cercariae were morphologically identified using low-power light microscopy. A total of six species of snails were collected throughout the study area, with Bulinus truncatus, B. forskalii, and Potadoma spp. being the most predominant species collected. Only the Bulinus species were tested for infection by cercarial shedding, of which only B. truncatus shed cercariae. Some B. truncatus shed mammalian schistosome cercariae, while others shed Gymnocephalus cercariae. Our results indicate that B. truncatus appears to be a potential intermediate host of schistosomiasis in Gabon, where cases of S. haematobium, S. guineensis, and S. intercalatum infection are reported. However, it will be important to further understand the species diversity and transmission dynamics of schistosomes.

15.
Angiogenesis ; 24(1): 177-190, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33113074

RESUMO

Integrin activation contributes to key blood cell functions including adhesion, proliferation and migration. An essential step in the cell signaling pathway that activates integrin requires the binding of talin to the ß-integrin cytoplasmic tail. Whereas this pathway is understood in platelets in detail, considerably less is known regarding how integrin-mediated adhesion in endothelium contributes to postnatal angiogenesis. We utilized an inducible EC-specific talin1 knock-out mouse (Tln1 EC-KO) and talin1 L325R knock-in mutant (Tln1 L325R) mouse, in which talin selectively lacks the capacity to activate integrins, to assess the role of integrin activation during angiogenesis. Deletion of talin1 during postnatal days 1-3 (P1-P3) caused lethality by P8 with extensive defects in retinal angiogenesis and widespread hemorrhaging. Tln1 EC-KO mice displayed reduced retinal vascular area, impaired EC sprouting and proliferation relative to Tln1 CTRLs. In contrast, induction of talin1 L325R in neonatal mice resulted in modest defects in retinal angiogenesis and mice survived to adulthood. Interestingly, deletion of talin1 or expression of talin1 L325R in ECs increased MAPK/ERK signaling. Strikingly, B16-F0 tumors grown in Tln1 L325R adult mice were 55% smaller and significantly less vascularized than tumors grown in littermate controls. EC talin1 is indispensable for postnatal development angiogenesis. The role of EC integrin activation appears context-dependent as its inhibition is compatible with postnatal development with mild defects in retinal angiogenesis but results in marked defects in tumor growth and angiogenesis. Inhibiting EC pan-integrin activation may be an effective approach to selectively target tumor blood vessel growth.


Assuntos
Células Endoteliais/citologia , Integrinas/metabolismo , Neovascularização Fisiológica , Talina/metabolismo , Animais , Animais Recém-Nascidos , Proliferação de Células , Células Endoteliais/metabolismo , Sistema de Sinalização das MAP Quinases , Camundongos Knockout , Mutação/genética , Neoplasias/irrigação sanguínea , Neoplasias/patologia , Neovascularização Patológica/metabolismo , Neovascularização Patológica/patologia , Retina/fisiologia , Talina/genética
17.
ACS Comb Sci ; 22(10): 533-541, 2020 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-32786324

RESUMO

Therapies that bind with immune cells and redirect their cytotoxic activity toward diseased cells represent a promising and versatile approach to immunotherapy with applications in cancer, lupus, and other diseases; traditional methods for discovering these therapies, however, are often time-intensive and lack the throughput of related target-based discovery approaches. Inspired by the observation that the cytokine, IL-12, can enhance antileukemic activity of the clinically approved T cell redirecting therapy, blinatumomab, here we describe the structure and assembly of a chimeric immune cell-redirecting agent which redirects the lytic activity of primary human T cells toward leukemic B cells and simultaneously cotargets the delivery of T cell-stimulating IL-12. We further describe a novel method for the parallel assembly of compositionally diverse libraries of these bispecific T cell engaging cytokines (BiTEokines) and their high-throughput phenotypic screening, requiring just days for hit identification and the analysis of composition-function relationships. Using this approach, we identified CD19 × CD3 × IL12 compounds that exhibit ex vivo lytic activity comparable to current FDA-approved therapies for leukemia and correlated drug treatment with specific cell-cell contact, cytokine delivery, and leukemia cell lysis. Given the modular nature of these multivalent compounds and their rapid assembly/screening, we anticipate facile extension of this therapeutic approach to a wide range of immune cells, diseased cells, and soluble protein combinations in the future.


Assuntos
Anticorpos Biespecíficos/farmacologia , Antineoplásicos/farmacologia , Interleucina-12/imunologia , Leucemia/tratamento farmacológico , Linfócitos T/imunologia , Anticorpos Biespecíficos/imunologia , Antígenos CD19/metabolismo , Antineoplásicos/imunologia , Linfócitos B , Complexo CD3/metabolismo , Humanos , Fatores Imunológicos/imunologia , Imunoterapia , Linfócitos T/efeitos dos fármacos
18.
Mol Nutr Food Res ; 64(11): e1901166, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32281732

RESUMO

SCOPE: Low-calorie sweetener (LCS) consumption is associated with metabolic disease in observational studies. However, physiologic mechanisms underlying LCS-induced metabolic impairments in humans are unclear. This study is aimed at identifying molecular pathways in adipose impacted by LCSs. METHODS AND RESULTS: Seven females with overweight or obesity, who did not report LCS use, consumed 12 ounces of diet soda containing sucralose and acesulfame-potassium (Ace-K) three times daily for 8 weeks. A subcutaneous adipose biopsy from the left abdomen and a fasting blood sample were collected at baseline and post-intervention. Global gene expression were assessed using RNA-sequencing followed by functional pathway analysis. No differences in circulating metabolic or inflammatory biomarkers were observed. However, ANOVA detected 828 differentially expressed annotated genes after diet soda consumption (p < 0.05), including transcripts for inflammatory cytokines. Fifty-eight of 140 canonical pathways represented in pathway analyses regulated inflammation, and several key upstream regulators of inflammation (e.g., TNF-alpha) were also represented. CONCLUSION: Consumption of diet soda with sucralose and Ace-K alters inflammatory transcriptomic pathways (e.g., NF-κB signaling) in subcutaneous adipose tissue but does not significantly alter circulating biomarkers. Findings highlight the need to examine molecular and metabolic effects of LCS exposure in a larger randomized control trial for a longer duration.


Assuntos
Tecido Adiposo/efeitos dos fármacos , Bebidas Adoçadas Artificialmente/efeitos adversos , Sacarose/análogos & derivados , Tiazinas/efeitos adversos , Tecido Adiposo/fisiologia , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Obesidade/metabolismo , Obesidade/fisiopatologia , Paniculite/induzido quimicamente , Paniculite/imunologia , Paniculite/metabolismo , Sacarose/efeitos adversos , Edulcorantes/efeitos adversos , Adulto Jovem
19.
Aging Cancer ; 1(1-4): 30-44, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35874875

RESUMO

The life expectancy of the world's elderly population (65 and older) continues to reach new milestones with older individuals currently comprising greater than 8.5% (617 million) of the world's population. This percentage is predicted to approach 20% of the world's population by 2050 (representing 1.6 billion people). Despite this amazing feat, many healthcare systems are not equipped to handle the multitude of diseases that commonly manifest with age, including most types of cancers. As the world's aging population grows, cancer treatments continue to evolve. Immunotherapies are a new drug class that has revolutionized our ability to treat previously intractable cancers; however, their efficacy in patients with compromised immune systems remains unclear. In this review, we will discuss how aging-associated losses in immune homeostasis impact the efficacy and safety of immunotherapy treatment in preclinical models of aging. We will also discuss how these findings translate to elderly patients receiving immunotherapy treatment for refractory and relapsed cancers, as well as, strategies that could be explored to improve the efficacy of immunotherapies in aged patients.

20.
BMC Public Health ; 19(1): 703, 2019 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-31174505

RESUMO

BACKGROUND: In an effort to complement the current chemotherapy based schistosomiasis control interventions in Shinyanga district, community knowledge, perceptions and water contact practices were qualitatively assessed using focus group discussions and semi structured interviews involving 271 participants in one S. haematobium prevalent community of Ikingwamanoti village, Shinyanga district, Northwestern, Tanzania. METHODS: In October, 2016 we conducted 29 parent semi structured interviews and 16 focus group discussions with a total of 168 parent informants. Adult participants were conveniently selected from three sub-villages of Butini, Miyu, and Bomani of Ikingwamanoti village, Shinyanga district. In March, 2017, a total of 103 children informants participated in 10 focus group discussions and 20 semi structured interviews, administered to children from standard four, five, six and seven attending Ikingwamanoti Primary School. Note taking and digital recorders were used to collect narrative data for thematic analysis of emergent themes. RESULTS: Among participants, 75% parents and 50% children considered urinary schistosomiasis as a low priority health problem. Of the informants, 70% children and 48.3% parents had misconceptions about the cause, modes of transmission and control of schistosomiasis demonstrating gaps in their biomedical knowledge of the disease. Assessment of treatment seeking behavior for urinary schistosomiasis revealed a combination of traditional and modern health care sectors. However, modern medicines were considered effective in the treatment of urinary schistosomiasis. Lack of alternative sources of water for domestic and recreational activities and unhygienic water use habits exposed community members to high risk of acquiring urinary schistosomiasis. CONCLUSION: Use of Schistosoma haematobium contaminated water sources for daily domestic and recreational use facilitated contraction of urinary schistosomiasis among community members in Shinyanga district. People's perceptions of urinary schistosomiasis as a less priority health problem promoted persistence of the disease. Future efforts to control urinary schistosomiasis should take into account integrated approaches combining water, sanitation and hygiene, health education, alternative sources of clean and safe water to facilitate behavior change.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Higiene , Pais/psicologia , Aceitação pelo Paciente de Cuidados de Saúde/psicologia , Schistosoma haematobium , Esquistossomose Urinária/psicologia , Adolescente , Adulto , Animais , Criança , Estudos Transversais , Transmissão de Doença Infecciosa , Feminino , Grupos Focais , Humanos , Masculino , Percepção , Prevalência , Pesquisa Qualitativa , Saneamento , Esquistossomose Urinária/epidemiologia , Esquistossomose Urinária/transmissão , Tanzânia/epidemiologia , Água
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