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1.
Hand (N Y) ; : 15589447231221170, 2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38240335

RESUMO

BACKGROUND: Nerve injuries from gunshot wounds (GSWs) to the upper arm can cause significant morbidity and loss of function. However, indications for surgical exploration and nerve reconstruction remain unclear as both low- and high-grade injuries can present with an abnormal neurological examination. METHODS: Adult patients presenting with a history of isolated GSW to the upper arm between 2010 and 2019 at a single urban level 1 trauma center were screened for inclusion in this retrospective study. Patient demographics, neurological examination findings, concurrent injuries, and intraoperative findings were gathered. Bivariate analysis was performed to characterize factors associated with nerve injuries. RESULTS: There were 139 adult patients with isolated brachial GSWs, and 49 patients (35%) presented with an abnormal neurological examination and significantly associated with concurrent humerus fractures (39% vs 21%, P = .026) and brachial artery injuries (31% vs 2%, P < .001). Thirty of these 49 patients were operatively explored. Fifteen patients were found to have observed nerve injuries during operative exploration including 8 patients with nerve transections. The radial nerve was the most commonly transected nerve (6), and among the 16 contused nerves, the median (8) was most common. CONCLUSION: Nerve injury from upper arm GSWs is common with directly traumatized nerves confirmed in at least 39% and nerve transection in at least 16% of patients with an abnormal neurological examination. Timely referral to a hand and/or peripheral nerve surgeon for close clinical follow-up, appropriate diagnosis, and any necessary surgical reconstruction with nerve grafts, tendon transfers, and nerve transfers is recommended.

2.
Neurobiol Learn Mem ; 208: 107881, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38135111

RESUMO

Stimuli in our environment are not always associated with an outcome. Some of these stimuli, depending on how they are presented, may gain inhibitory value or simply be ignored. If experienced in the presence of other cues predictive of appetitive or aversive outcomes, they typically gain inhibitory value and become predictive cues indicating the absence of appetitive or aversive outcomes. In this case, these cues are referred to as conditioned inhibitors. Here, male and female Long Evans rats underwent cue discrimination training where a reward cue was paired with sucrose, a fear cue with footshock, and an inhibitor cue resulted in neither sucrose or footshock. During a subsequent summation test for conditioned inhibition of fear and reward, the inhibitor cue was presented concurrently with the reward and fear cues without any outcome, intermixed with trials of reinforced reward and fear trials. Males showed significant conditioned inhibition of freezing, while females did not, which was not dependent on estrous. Both males and females showed significant conditioned inhibition of reward. During a retardation of fear acquisition test, the inhibitor was paired with footshock and both males and females showed delayed acquisition of fear. During a retardation of reward acquisition test, the inhibitor was paired with sucrose, and females showed delayed acquisition of reward, while males did not. In summary, males and females showed significant reward-fear-inhibitor cue discrimination, conditioned inhibition of reward, and retardation of fear acquisition. The main sex difference, which was not estrous-dependent, was the lack of conditioned inhibition of freezing in females. These data imply that while the inhibitor cue gained some inhibitory value in the females, the strength of this inhibitory value may not have been great enough to effectively downregulate freezing elicited by the fear cue.


Assuntos
Condicionamento Clássico , Recompensa , Ratos , Feminino , Masculino , Animais , Ratos Long-Evans , Condicionamento Clássico/fisiologia , Sinais (Psicologia) , Medo/fisiologia , Sacarose
3.
Exp Hematol ; 128: 48-66, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37611729

RESUMO

Hyperactivation of JAK2 kinase is a unifying feature of human Ph- myeloproliferative neoplasms (MPNs), most commonly due to the JAK2 V617F mutation. Mice harboring a homologous mutation in the Jak2 locus exhibit a phenotype resembling polycythemia vera. NFκB pathway hyperactivation is present in myeloid neoplasms, including MPNs, despite scarcity of mutations in NFκB pathway genes. To determine the impact of NFκB pathway hyperactivation in conjunction with Jak2 V617F, we utilized Ikk2 (Ikk2-CA) mice. Pan-hematopoietic Ikk2-CA alone produced depletion of hematopoietic stem cells and B cells. When combined with the Jak2 V617F mutation, Ikk2-CA rescued the polycythemia vera phenotype of Jak2 V617F. Likewise, Jak2 V617F ameliorated defects in hematopoiesis produced by Ikk2-CA. Single-cell RNA sequencing of hematopoietic stem and progenitor cells revealed multiple genes antagonistically regulated by Jak2 and Ikk2, including subsets whose expression was altered by Jak2 V617F and/or Ikk2-CA but partly or fully rectified in the double mutant. We hypothesize that Jak2 promotes hematopoietic stem cell population self-renewal, whereas Ikk2 promotes myeloid lineage differentiation, and biases cell fates at several branch points in hematopoiesis. Jak2 and Ikk2 both regulate multiple genes affecting myeloid maturation and cell death. Therefore, the presence of dual Jak2 and NFκB hyperactivation may present neomorphic therapeutic vulnerabilities in myeloid neoplasms.


Assuntos
Transtornos Mieloproliferativos , Policitemia Vera , Camundongos , Humanos , Animais , Policitemia Vera/genética , Janus Quinase 2/genética , Janus Quinase 2/metabolismo , Transtornos Mieloproliferativos/genética , Transtornos Mieloproliferativos/metabolismo , Mutação , Células-Tronco Hematopoéticas/metabolismo , Hematopoese/genética , Proteínas Serina-Treonina Quinases/genética
4.
Injury ; 54(7): 110755, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37150723

RESUMO

INTRODUCTION: Upper Extremity gunshot wounds represent a significant strain on community and hospital resources, and reports of their epidemiology are varied. We hypothesized that demographic and socioeconomic variables would be associated with variable injury patterns and management, and that two distinct populations would be affected by upper extremity ballistic injury based on violent versus accidental, self-inflicted mechanism. MATERIALS & METHODS: Retrospective review of all adult patients sustaining ballistic injury to the upper extremity at a single urban Level I trauma center over 10 years (n = 797). Demographic, injury pattern, treatment, and outcomes data were collected. Comparisons between groups were conducted with unpaired t-tests and chi-square testing where appropriate. RESULTS: Most patients were male (89.1%) and mean age was 30.1 years (18-83). Violence accounted for 89.1% of injuries. Black individuals were disproportionately affected at 87% of patients. Shoulder injuries were most common (34%), and wrist least common (7%). Demographics and injury pattern varied significantly between patients sustaining violent injury and those with self-inflicted mechanisms. Patients sustaining violent injury were most often young, Black men more likely to be injured proximally, whereas patients with self-inflicted injuries were more likely to be older, Caucasian men with more comorbidities injured distally. Cumulatively, 35.3% of patients required operative intervention. Distal injuries were more likely operative. The most commonly injured structure across all levels was bone (53%), and 54.3% of fractures required operation. Median follow-up was 24.5 months. Complication rate was 13.6%. CONCLUSIONS: Gunshot wounds of the upper extremity create complex patterns of injury which vary based on level of injury and mechanism. Violent and self-inflicted injuries occur in dissimilar populations and result in distinctive injury patterns.


Assuntos
Fraturas Ósseas , Ferimentos por Arma de Fogo , Adulto , Humanos , Masculino , Feminino , Ferimentos por Arma de Fogo/epidemiologia , Ferimentos por Arma de Fogo/cirurgia , Ferimentos por Arma de Fogo/complicações , Fraturas Ósseas/cirurgia , Extremidade Superior/lesões , Estudos Retrospectivos , Violência
5.
Nat Commun ; 14(1): 1601, 2023 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-36959190

RESUMO

Imaging Mass Cytometry (IMC) is an emerging multiplexed imaging technology for analyzing complex microenvironments using more than 40 molecularly-specific channels. However, this modality has unique data processing requirements, particularly for patient tissue specimens where signal-to-noise ratios for markers can be low, despite optimization, and pixel intensity artifacts can deteriorate image quality and downstream analysis. Here we demonstrate an automated content-aware pipeline, IMC-Denoise, to restore IMC images deploying a differential intensity map-based restoration (DIMR) algorithm for removing hot pixels and a self-supervised deep learning algorithm for shot noise image filtering (DeepSNiF). IMC-Denoise outperforms existing methods for adaptive hot pixel and background noise removal, with significant image quality improvement in modeled data and datasets from multiple pathologies. This includes in technically challenging human bone marrow; we achieve noise level reduction of 87% for a 5.6-fold higher contrast-to-noise ratio, and more accurate background noise removal with approximately 2 × improved F1 score. Our approach enhances manual gating and automated phenotyping with cell-scale downstream analyses. Verified by manual annotations, spatial and density analysis for targeted cell groups reveal subtle but significant differences of cell populations in diseased bone marrow. We anticipate that IMC-Denoise will provide similar benefits across mass cytometric applications to more deeply characterize complex tissue microenvironments.


Assuntos
Algoritmos , Tomografia Computadorizada por Raios X , Humanos , Razão Sinal-Ruído , Tomografia Computadorizada por Raios X/métodos , Artefatos , Citometria por Imagem , Processamento de Imagem Assistida por Computador/métodos
6.
Hand (N Y) ; : 15589447221150515, 2023 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-36734277

RESUMO

BACKGROUND: Prophylactic antibiotics are variably prescribed after isolated upper extremity gunshot wounds (UE GSWs). The risk of infection and factors influencing prescribing practice remain poorly understood, and clinical practice guidelines are lacking. METHODS: Adults with isolated UE GSWs over a 10-year period were included. Medical records were reviewed for demographic and injury variables, comorbidities, surgical treatments, antibiotic administration, infectious complications, and follow-up duration. Infection rate was calculated. Bivariate and multivariable linear regression analyses were used to identify patient-related and injury-related factors predictive of prophylactic antibiotic prescription. RESULTS: A total of 281 patients were eligible for inclusion. Prophylactic antibiotics were prescribed at discharge for 111 patients (40%). Multivariable analysis revealed that patients with more distal injuries and ballistic fractures were significantly more likely to receive prophylactic antibiotics. Of patients with at least 30-day postinjury follow-up, 6% developed infections. CONCLUSION: Prophylactic antibiotic administration after UE GSWs was inconsistent but more common in patients with ballistic fractures and injuries in the hand. The overall incidence of infection was found to lie between 3% and 6%. The rate of infection in the antibiotic prophylaxis (2%-6%) group was similar to that in the no-antibiotic (5%-7%) group, suggesting that antibiotic prophylaxis may not have a large impact on infectious risk. However, because this study is nonrandomized, and because this study is underpowered for multivariable modeling of infectious risk, it remains possible that subgroups of this population may still benefit from antibiotic prophylaxis.

7.
Psychopharmacology (Berl) ; 240(3): 609-621, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35960326

RESUMO

RATIONALE: Stressful events can have lasting and impactful effects on behavior, especially in terms of appropriate fear regulation and reward seeking. Our prior work in rats has shown baseline sex differences in fear expression and sucrose seeking in a discriminative reward-fear-safety conditioning task. OBJECTIVES: The objectives of the current study were to determine how prior stress may affect alcohol consumption across a reward-fear-safety learning task, and how prior alcohol history may interact with stress to impact learning in this task. METHODS: Male and female Long Evans rats were given home cage intermittent 24 h access to both water and alcohol for 5 weeks. A subset of rats then received exposure to stress (15 unsignaled footshocks), while remaining unstressed rats received context exposure without shock. One week later, all rats were trained on the same reward-fear-safety cue task while having continuous home cage access to both water and alcohol. RESULTS: All rats increased consumption (g/kg/24 h) across the 5 weeks of intermittent access, with females showing higher consumption levels. Stress exposure did not alter alcohol consumption in the week following stress, but did increase home cage alcohol consumption during later reward-fear-safety cue learning. Stress in both sexes also elevated freezing levels to the reward cue resulting in decreased sucrose seeking and was positively correlated with home cage alcohol consumption. CONCLUSIONS: While stress increased drinking in both males and females, the effects of stress were particularly pronounced in females, indicating our results could be capturing a higher propensity for females to display stress-induced drinking.


Assuntos
Etanol , Medo , Ratos , Feminino , Masculino , Animais , Ratos Long-Evans , Medo/fisiologia , Etanol/farmacologia , Recompensa , Sacarose/farmacologia , Consumo de Bebidas Alcoólicas
8.
Leuk Res Rep ; 18: 100353, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36275842

RESUMO

Acute promyelocytic leukemia (APL) often presents with significant coagulopathy which may result in both hemorrhagic and thrombotic complications. The emergence of the COVID-19 pandemic has complicated the initial treatment and diagnosis of APL owing to the viral infection's own associated coagulopathy. Here we report two cases of APL newly diagnosed in the setting of COVID-19 infection and considerations in their management. Included is a discussion of strategies for the dosing of arsenic trioxide in patients with significant obesity and renal insufficiency. The case series submitted does not represent a study on patients and thus no specific informed consents or permissions were required. All images included in our manuscript have been deidentified and all authors certify that personal details that could potentially be used to identify the patients in the cases described have been removed. The corresponding author has personally confirmed that both patients included in this study have given verbal permission to present their cases in the de-identified manner as described above.

9.
Front Neurol ; 12: 651096, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34149593

RESUMO

Events of status epilepticus (SE) trigger the development of temporal lobe epilepsy (TLE), a type of focal epilepsy that is commonly drug-resistant and is highly comorbid with cognitive deficits. While SE-induced hippocampal injury, accompanied by gliosis and neuronal loss, typically disrupts cognitive functions resulting in memory defects, it is not definitively known how. Our previous studies revealed extensive hippocampal microgliosis that peaked between 2 and 3 weeks after SE and paralleled the development of cognitive impairments, suggesting a role for reactive microglia in this pathophysiology. Microglial survival and proliferation are regulated by the colony-stimulating factor 1 receptor (CSF1R). The CSF1R inhibitor PLX3397 has been shown to reduce/deplete microglial populations and improve cognitive performance in models of neurodegenerative disorders. Therefore, we hypothesized that suppression of microgliosis with PLX3397 during epileptogenesis may attenuate the hippocampal-dependent spatial learning and memory deficits in the rat pilocarpine model of SE and acquired TLE. Different groups of control and SE rats were fed standard chow (SC) or chow with PLX3397 starting immediately after SE and for 3 weeks. Novel object recognition (NOR) and Barnes maze (BM) were performed to determine memory function between 2 and 3 weeks after SE. Then microglial populations were assessed using immunohistochemistry. Control rats fed with either SC or PLX3397 performed similarly in both NOR and BM tests, differentiating novel vs. familiar objects in NOR, and rapidly learning the location of the hidden platform in BM. In contrast, both SE groups (SC and PLX3397) showed significant deficits in both NOR and BM tests compared to controls. Both PLX3397-treated control and SE groups had significantly decreased numbers of microglia in the hippocampus (60%) compared to those in SC. In parallel, we found that PLX3397 treatment also reduced SE-induced hippocampal astrogliosis. Thus, despite drastic reductions in microglial cells, memory was unaffected in the PLX3397-treated groups compared to those in SC, suggesting that remaining microglia may be sufficient to help maintain hippocampal functions. In sum, PLX3397 did not improve or worsen the memory deficits in rats that sustained pilocarpine-induced SE. Further research is required to determine whether microglia play a role in cognitive decline during epileptogenesis.

10.
Mol Ther ; 28(12): 2540-2552, 2020 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-32877695

RESUMO

Enhancing the immunogenicity of tumor-associated antigens would represent a major advance for anti-tumor vaccination strategies. Here, we investigated structure-directed antigen destabilization as a strategy to improve the degradation, immunogenic epitope presentation, and T cell activation against a vesicular stomatitis virus (VSV)-encoded tumor antigen. We used the crystal structure of the model antigen ovalbumin to identify charge-disrupting amino acid mutations that were predicted to decrease the stability of the protein. One mutation, OVA-C12R, significantly reduced the half-life of the protein and was preferentially degraded in a 26-S proteasomal-dependent manner. The destabilized ovalbumin protein exhibited enhanced presentation of the major histocompatibility complex (MHC) class I immunogenic epitope, SIINFEKL, on the surface of B16F10 cells or murine bone marrow-derived dendritic cells (BMDCs) in vitro. Enhanced presentation correlated with better recognition by cognate CD8 OT-I T cells as measured by activation, proliferation, and effector cytokine production. Finally, VSV encoding the degradation-prone antigen was better able to prime an antigen ovalbumin-specific CD8 T cell response in vivo without altering the anti-viral CD8 T cell response. Our studies highlight that not only is the choice of antigen in cancer vaccines of importance, but that emphasis should be placed on modifying antigen quality to ensure optimal priming of anti-tumor responses.


Assuntos
Antígenos de Neoplasias/genética , Linfócitos T CD8-Positivos/imunologia , Vetores Genéticos/imunologia , Imunidade , Ativação Linfocitária , Ovalbumina/genética , Vesiculovirus/genética , Animais , Apresentação de Antígeno , Antígenos de Neoplasias/química , Vacinas Anticâncer/imunologia , Linhagem Celular Tumoral , Células Dendríticas/imunologia , Epitopos/imunologia , Feminino , Células HEK293 , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Terapia Viral Oncolítica/métodos , Ovalbumina/química , Estabilidade Proteica
11.
Nat Commun ; 11(1): 3187, 2020 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-32581235

RESUMO

The application of adoptive T cell therapies, including those using chimeric antigen receptor (CAR)-modified T cells, to solid tumors requires combinatorial strategies to overcome immune suppression associated with the tumor microenvironment. Here we test whether the inflammatory nature of oncolytic viruses and their ability to remodel the tumor microenvironment may help to recruit and potentiate the functionality of CAR T cells. Contrary to our hypothesis, VSVmIFNß infection is associated with attrition of murine EGFRvIII CAR T cells in a B16EGFRvIII model, despite inducing a robust proinflammatory shift in the chemokine profile. Mechanistically, type I interferon (IFN) expressed following infection promotes apoptosis, activation, and inhibitory receptor expression, and interferon-insensitive CAR T cells enable combinatorial therapy with VSVmIFNß. Our study uncovers an unexpected mechanism of therapeutic interference, and prompts further investigation into the interaction between CAR T cells and oncolytic viruses to optimize combination therapy.


Assuntos
Imunoterapia Adotiva , Interferon beta/metabolismo , Vírus Oncolíticos/metabolismo , Receptores de Antígenos Quiméricos/metabolismo , Linfócitos T/metabolismo , Animais , Apoptose , Linhagem Celular Tumoral , Quimiocinas/metabolismo , Terapia Combinada , Feminino , Interferon beta/genética , Ativação Linfocitária , Melanoma Experimental/imunologia , Melanoma Experimental/terapia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Mutantes , Terapia Viral Oncolítica , Vírus Oncolíticos/genética , Receptor de Interferon alfa e beta/genética , Receptor de Interferon alfa e beta/metabolismo , Receptores de Antígenos de Linfócitos T/metabolismo , Baço/imunologia
12.
Nat Commun ; 11(1): 790, 2020 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-32034147

RESUMO

APOBEC3B, an anti-viral cytidine deaminase which induces DNA mutations, has been implicated as a mediator of cancer evolution and therapeutic resistance. Mutational plasticity also drives generation of neoepitopes, which prime anti-tumor T cells. Here, we show that overexpression of APOBEC3B in tumors increases resistance to chemotherapy, but simultaneously heightens sensitivity to immune checkpoint blockade in a murine model of melanoma. However, in the vaccine setting, APOBEC3B-mediated mutations reproducibly generate heteroclitic neoepitopes in vaccine cells which activate de novo T cell responses. These cross react against parental, unmodified tumors and lead to a high rate of cures in both subcutaneous and intra-cranial tumor models. Heteroclitic Epitope Activated Therapy (HEAT) dispenses with the need to identify patient specific neoepitopes and tumor reactive T cells ex vivo. Thus, actively driving a high mutational load in tumor cell vaccines increases their immunogenicity to drive anti-tumor therapy in combination with immune checkpoint blockade.


Assuntos
Vacinas Anticâncer/farmacologia , Citidina Desaminase/imunologia , Imunoterapia/métodos , Antígenos de Histocompatibilidade Menor/imunologia , Linfócitos T/imunologia , Animais , Linhagem Celular Tumoral , Citidina Desaminase/genética , Citidina Desaminase/metabolismo , Resistencia a Medicamentos Antineoplásicos , Epitopos/imunologia , Feminino , Humanos , Células Matadoras Naturais/imunologia , Melanoma/imunologia , Melanoma/terapia , Melanoma Experimental/imunologia , Melanoma Experimental/terapia , Camundongos Endogâmicos C57BL , Antígenos de Histocompatibilidade Menor/genética , Antígenos de Histocompatibilidade Menor/metabolismo , Mutação , Evasão Tumoral/efeitos dos fármacos
13.
J Immunother Cancer ; 7(1): 188, 2019 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-31315671

RESUMO

BACKGROUND: Immunotherapy has shown remarkable clinical promise in the treatment of various types of cancers. However, clinical benefits derive from a highly inflammatory mechanism of action. This presents unique challenges for use in pediatric brainstem tumors including diffuse intrinsic pontine glioma (DIPG), since treatment-related inflammation could cause catastrophic toxicity. Therefore, the goal of this study was to investigate whether inflammatory, immune-based therapies are likely to be too dangerous to pursue for the treatment of pediatric brainstem tumors. METHODS: To complement previous immunotherapy studies using patient-derived xenografts in immunodeficient mice, we developed fully immunocompetent models of immunotherapy using transplantable, syngeneic tumors. These four models - HSVtk/GCV suicide gene immunotherapy, oncolytic viroimmunotherapy, adoptive T cell transfer, and CAR T cell therapy - have been optimized to treat tumors outside of the CNS and induce a broad spectrum of inflammatory profiles, maximizing the chances of observing brainstem toxicity. RESULTS: All four models achieved anti-tumor efficacy in the absence of toxicity, with the exception of recombinant vaccinia virus expressing GMCSF, which demonstrated inflammatory toxicity. Histology, imaging, and flow cytometry confirmed the presence of brainstem inflammation in all models. Where used, the addition of immune checkpoint blockade did not introduce toxicity. CONCLUSIONS: It remains imperative to regard the brainstem with caution for immunotherapeutic intervention. Nonetheless, we show that further careful development of immunotherapies for pediatric brainstem tumors is warranted to harness the potential potency of anti-tumor immune responses, despite their possible toxicity within this anatomically sensitive location.


Assuntos
Neoplasias do Tronco Encefálico/terapia , Glioma Pontino Intrínseco Difuso/terapia , Terapia Genética/métodos , Imunoterapia Adotiva/métodos , Terapia Viral Oncolítica/métodos , Linfócitos T/transplante , Animais , Neoplasias do Tronco Encefálico/genética , Neoplasias do Tronco Encefálico/imunologia , Linhagem Celular Tumoral , Glioma Pontino Intrínseco Difuso/imunologia , Feminino , Genes Transgênicos Suicidas , Terapia Genética/efeitos adversos , Fator Estimulador de Colônias de Granulócitos e Macrófagos/genética , Humanos , Imunoterapia Adotiva/efeitos adversos , Camundongos , Terapia Viral Oncolítica/efeitos adversos , Resultado do Tratamento , Vaccinia virus/genética , Ensaios Antitumorais Modelo de Xenoenxerto
14.
Cancer Immunol Res ; 7(5): 828-840, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30940643

RESUMO

Antitumor T-cell responses raised by first-line therapies such as chemotherapy, radiation, tumor cell vaccines, and viroimmunotherapy tend to be weak, both quantitatively (low frequency) and qualitatively (low affinity). We show here that T cells that recognize tumor-associated antigens can directly kill tumor cells if used at high effector-to-target ratios. However, when these tumor-reactive T cells were present at suboptimal ratios, direct T-cell-mediated tumor cell killing was reduced and the ability of tumor cells to evolve away from a coapplied therapy (oncolytic or suicide gene therapy) was promoted. This T-cell-mediated increase in therapeutic resistance was associated with C to T transition mutations that are characteristic of APOBEC3 cytosine deaminase activity and was induced through a TNFα and protein kinase C-dependent pathway. Short hairpin RNA inhibition of endogenous APOBEC3 reduced rates of tumor escape from oncolytic virus or suicide gene therapy to those seen in the absence of antitumor T-cell coculture. Conversely, overexpression of human APOBEC3B in tumor cells enhanced escape from suicide gene therapy and oncolytic virus therapy both in vitro and in vivo Our data suggest that weak affinity or low frequency T-cell responses against tumor antigens may contribute to the ability of tumor cells to evolve away from first-line therapies. We conclude that immunotherapies need to be optimized as early as possible so that, if they do not kill the tumor completely, they do not promote treatment resistance.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Imunoterapia , Melanoma Experimental/terapia , Animais , Antígenos de Neoplasias/genética , Antígenos de Neoplasias/imunologia , Linhagem Celular Tumoral , Citidina Desaminase/genética , Citidina Desaminase/imunologia , Feminino , Ganciclovir/uso terapêutico , Orthoreovirus Mamífero 3 , Melanoma Experimental/genética , Melanoma Experimental/imunologia , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Antígenos de Histocompatibilidade Menor/genética , Antígenos de Histocompatibilidade Menor/imunologia , Mutação , Terapia Viral Oncolítica , Evasão Tumoral
15.
Vasc Endovascular Surg ; 53(2): 104-111, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30497352

RESUMO

INTRODUCTION:: In patients who receive chronic hemodialysis but do not have autogenous venous conduit for a native dialysis access, nonautologous grafts serve as an alternative conduit of choice. This study compared the clinical outcome of hemodialysis access using bovine carotid artery graft (BCAG) and prosthetic polytetrafluoroethylene (PTFE) graft in patients who receive chronic hemodialysis. METHODS:: An analysis of all patients undergoing hemodialysis using either BCAG or PTFE grafts from 2010 to 2017 was performed. Clinical outcomes were analyzed including graft patency as well as associated complications related to dialysis grafts and tunneled dialysis catheter (TDC). RESULTS:: During the study period, 142 patients received BCAG and 128 patients received PTFE graft implantation for dialysis access. The mean duration from graft implantation to graft cannulation in the BCAG and PTFE group was 12.3 ± 8.5 days versus 43.5 ± 16.4, respectively ( P = .01). Bovine carotid artery graft group had a higher 2-year primary patency rate (33% vs 14%, P = .03) and assisted primary rate (57% vs 23%, P = .02) compared to the PTFE group. The 2-year secondary patency rates were similar between the 2 groups (56% vs 53%, P = .69). Complication rates in the BCAG and PTFE group was 1.69 ± 0.24 per patient-year versus 2.54 ± 0.48 per patient-year, respectively ( P = .01). Tunneled dialysis catheter-related infection was greater in the PTFE group compared to the BCAG group (10.87 ± 2.61 vs 5.69 ± 0.98 per 1000 TDC days; P = .02). Bovine carotid artery graft cohorts group required a mean of 1.69 interventions per patient-year, compared to 2.76 per patient-year for the PTFE group ( P = .03). CONCLUSIONS:: Bovine carotid artery graft permits earlier cannulation for hemodialysis access with superior primary and assisted primary patency rates compared to PTFE grafts. Patients with BCAG experienced shorter indwelling TDC duration and less TDC-related complications compared to PTFE cohorts.


Assuntos
Derivação Arteriovenosa Cirúrgica/instrumentação , Bioprótese , Implante de Prótese Vascular/instrumentação , Prótese Vascular , Artérias Carótidas/transplante , Cateterismo , Politetrafluoretileno , Diálise Renal , Extremidade Superior/irrigação sanguínea , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Derivação Arteriovenosa Cirúrgica/efeitos adversos , Implante de Prótese Vascular/efeitos adversos , Cateterismo/efeitos adversos , Cateteres de Demora , Bovinos , Bases de Dados Factuais , Feminino , Oclusão de Enxerto Vascular/etiologia , Oclusão de Enxerto Vascular/fisiopatologia , Xenoenxertos , Humanos , Masculino , Pessoa de Meia-Idade , Desenho de Prótese , Diálise Renal/efeitos adversos , Diálise Renal/instrumentação , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento , Grau de Desobstrução Vascular , Adulto Jovem
16.
Mol Ther Oncolytics ; 11: 1-13, 2018 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-30294666

RESUMO

Tumor cells frequently evade applied therapies through the accumulation of genomic mutations and rapid evolution. In the case of oncolytic virotherapy, understanding the mechanisms by which cancer cells develop resistance to infection and lysis is critical to the development of more effective viral-based platforms. Here, we identify APOBEC3 as an important factor that restricts the potency of oncolytic vesicular stomatitis virus (VSV). We show that VSV infection of B16 murine melanoma cells upregulated APOBEC3 in an IFN-ß-dependent manner, which was responsible for the evolution of virus-resistant cell populations and suggested that APOBEC3 expression promoted the acquisition of a virus-resistant phenotype. Knockdown of APOBEC3 in B16 cells diminished their capacity to develop resistance to VSV infection in vitro and enhanced the therapeutic effect of VSV in vivo. Similarly, overexpression of human APOBEC3B promoted the acquisition of resistance to oncolytic VSV both in vitro and in vivo. Finally, we demonstrate that APOBEC3B expression had a direct effect on the fitness of VSV, an RNA virus that has not previously been identified as restricted by APOBEC3B. This research identifies APOBEC3 enzymes as key players to target in order to improve the efficacy of viral or broader nucleic acid-based therapeutic platforms.

17.
Clin Cancer Res ; 24(17): 4215-4224, 2018 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-29798908

RESUMO

Purpose: Virotherapies are maturing in the clinical setting. Adenoviruses (Ad) are excellent vectors for the manipulability and tolerance of transgenes. Poor tumor selectivity, off-target sequestration, and immune inactivation hamper clinical efficacy. We sought to completely redesign Ad5 into a refined, tumor-selective virotherapy targeted to αvß6 integrin, which is expressed in a range of aggressively transformed epithelial cancers but nondetectable in healthy tissues.Experimental Design: Ad5NULL-A20 harbors mutations in each major capsid protein to preclude uptake via all native pathways. Tumor-tropism via αvß6 targeting was achieved by genetic insertion of A20 peptide (NAVPNLRGDLQVLAQKVART) within the fiber knob protein. The vector's selectivity in vitro and in vivo was assessed.Results: The tropism-ablating triple mutation completely blocked all native cell entry pathways of Ad5NULL-A20 via coxsackie and adenovirus receptor (CAR), αvß3/5 integrins, and coagulation factor 10 (FX). Ad5NULL-A20 efficiently and selectively transduced αvß6+ cell lines and primary clinical ascites-derived EOC ex vivo, including in the presence of preexisting anti-Ad5 immunity. In vivo biodistribution of Ad5NULL-A20 following systemic delivery in non-tumor-bearing mice was significantly reduced in all off-target organs, including a remarkable 107-fold reduced genome accumulation in the liver compared with Ad5. Tumor uptake, transgene expression, and efficacy were confirmed in a peritoneal SKOV3 xenograft model of human EOC, where oncolytic Ad5NULL-A20-treated animals demonstrated significantly improved survival compared with those treated with oncolytic Ad5.Conclusions: Oncolytic Ad5NULL-A20 virotherapies represent an excellent vector for local and systemic targeting of αvß6-overexpressing cancers and exciting platforms for tumor-selective overexpression of therapeutic anticancer modalities, including immune checkpoint inhibitors. Clin Cancer Res; 24(17); 4215-24. ©2018 AACR.


Assuntos
Antígenos de Neoplasias/genética , Carcinoma Epitelial do Ovário/genética , Carcinoma Epitelial do Ovário/terapia , Integrinas/genética , Terapia Viral Oncolítica , Adenoviridae/genética , Animais , Carboidratos Epimerases/genética , Carcinoma Epitelial do Ovário/patologia , Carcinoma Epitelial do Ovário/virologia , Linhagem Celular Tumoral , Proteína de Membrana Semelhante a Receptor de Coxsackie e Adenovirus/genética , Feminino , Genes cdc/genética , Vetores Genéticos/genética , Vetores Genéticos/farmacologia , Humanos , Cetona Oxirredutases/genética , Camundongos , Vírus Oncolíticos/genética , Distribuição Tecidual , Transdução Genética , Tropismo/genética
18.
Clin Infect Dis ; 67(6): 905-912, 2018 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-29718144

RESUMO

Background: Multidrug-resistant organisms (MDROs) are an important cause of morbidity and mortality after solid organ transplantation. We aimed to characterize MDRO colonization dynamics and infection in liver transplant (LT) recipients through innovative use of active surveillance and whole-genome sequencing (WGS). Methods: We prospectively enrolled consecutive adult patients undergoing LT from March 2014 to March 2016. Fecal samples were collected at multiple timepoints from time of enrollment to 12 months posttransplant. Samples were screened for carbapenem-resistant Enterobacteriaceae (CRE), Enterobacteriaceae resistant to third-generation cephalosporins (Ceph-RE), and vancomycin-resistant enterococci. We performed WGS of CRE and selected Ceph-RE isolates. We also collected clinical data including demographics, transplant characteristics, and infection data. Results: We collected 998 stool samples and 119 rectal swabs from 128 patients. MDRO colonization was detected in 86 (67%) patients at least once and was significantly associated with subsequent MDRO infection (0 vs 19.8%, P = .002). Child-Turcotte-Pugh score at LT and duration of post-LT hospitalization were independent predictors of both MDRO colonization and infection. Temporal dynamics differed between MDROs with respect to onset of colonization, clearance, and infections. We detected an unexpected diversity of CRE colonizing isolates and previously unrecognized transmission that spanned Ceph-RE and CRE phenotypes, as well as a cluster of mcr-1-producing isolates. Conclusions: Active surveillance and WGS showed that MDRO colonization is a highly dynamic and complex process after LT. Understanding that complexity is crucial for informing decisions regarding MDRO infection control, use of therapeutic decolonization, and empiric treatment regimens.


Assuntos
Bactérias/genética , Portador Sadio/microbiologia , Farmacorresistência Bacteriana Múltipla , Variação Genética , Transplante de Fígado , Idoso , Bactérias/efeitos dos fármacos , Bactérias/isolamento & purificação , Enterobacteriáceas Resistentes a Carbapenêmicos/efeitos dos fármacos , Enterobacteriáceas Resistentes a Carbapenêmicos/genética , Enterobacteriáceas Resistentes a Carbapenêmicos/isolamento & purificação , Infecção Hospitalar , Fezes/microbiologia , Feminino , Genômica , Humanos , Masculino , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/genética , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Pessoa de Meia-Idade , Estudos Prospectivos , Vigilância de Evento Sentinela , Transplantados , Enterococos Resistentes à Vancomicina/efeitos dos fármacos , Enterococos Resistentes à Vancomicina/genética , Enterococos Resistentes à Vancomicina/isolamento & purificação , Sequenciamento Completo do Genoma
19.
Cancer Immunol Res ; 5(11): 1029-1045, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-29038298

RESUMO

Understanding how incompletely cleared primary tumors transition from minimal residual disease (MRD) into treatment-resistant, immune-invisible recurrences has major clinical significance. We show here that this transition is mediated through the subversion of two key elements of innate immunosurveillance. In the first, the role of TNFα changes from an antitumor effector against primary tumors into a growth promoter for MRD. Second, whereas primary tumors induced a natural killer (NK)-mediated cytokine response characterized by low IL6 and elevated IFNγ, PD-L1hi MRD cells promoted the secretion of IL6 but minimal IFNγ, inhibiting both NK-cell and T-cell surveillance. Tumor recurrence was promoted by trauma- or infection-like stimuli inducing VEGF and TNFα, which stimulated the growth of MRD tumors. Finally, therapies that blocked PD-1, TNFα, or NK cells delayed or prevented recurrence. These data show how innate immunosurveillance mechanisms, which control infection and growth of primary tumors, are exploited by recurrent, competent tumors and identify therapeutic targets in patients with MRD known to be at high risk of relapse. Cancer Immunol Res; 5(11); 1029-45. ©2017 AACR.


Assuntos
Células Matadoras Naturais/imunologia , Melanoma Experimental/imunologia , Recidiva Local de Neoplasia/imunologia , Neoplasias Cutâneas/imunologia , Linfócitos T/imunologia , Fator de Necrose Tumoral alfa/imunologia , Animais , Anticorpos/uso terapêutico , Linhagem Celular Tumoral , Citocinas/imunologia , Feminino , Ganciclovir/uso terapêutico , Vigilância Imunológica , Melanoma Experimental/terapia , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Terapia Viral Oncolítica , Paclitaxel/uso terapêutico , Reoviridae , Neoplasias Cutâneas/terapia , Linfócitos T/transplante
20.
Open Forum Infect Dis ; 4(3): ofx115, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28721352

RESUMO

The spread of mcr-1 in the United States remains poorly defined. mcr-1-producing Escherichia coli that also carried blaSHV-12 was detected in a hospitalized patient. No additional cases were identified during screening of 801 Gram-negative isolates. Genomic sequencing identified an IncX4 mcr-1- harboring plasmid and ST117 clonal background associated with avian pathogenic E coli.

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