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Importance: Lung cancer is the deadliest cancer in the US. Early-stage lung cancer detection with lung cancer screening (LCS) through low-dose computed tomography (LDCT) improves outcomes. Objective: To assess the association of a multifaceted clinical decision support intervention with rates of identification and completion of recommended LCS-related services. Design, Setting, and Participants: This nonrandomized controlled trial used an interrupted time series design, including 3 study periods from August 24, 2019, to April 27, 2022: baseline (12 months), period 1 (11 months), and period 2 (9 months). Outcome changes were reported as shifts in the outcome level at the beginning of each period and changes in monthly trend (ie, slope). The study was conducted at primary care and pulmonary clinics at a health care system headquartered in Salt Lake City, Utah, among patients aged 55 to 80 years who had smoked 30 pack-years or more and were current smokers or had quit smoking in the past 15 years. Data were analyzed from September 2023 through February 2024. Interventions: Interventions in period 1 included clinician-facing preventive care reminders, an electronic health record-integrated shared decision-making tool, and narrative LCS guidance provided in the LDCT ordering screen. Interventions in period 2 included the same clinician-facing interventions and patient-facing reminders for LCS discussion and LCS. Main Outcome and Measure: The primary outcome was LCS care gap closure, defined as the identification and completion of recommended care services. LCS care gap closure could be achieved through LDCT completion, other chest CT completion, or LCS shared decision-making. Results: The study included 1865 patients (median [IQR] age, 64 [60-70] years; 759 female [40.7%]). The clinician-facing intervention (period 1) was not associated with changes in level but was associated with an increase in slope of 2.6 percentage points (95% CI, 2.4-2.7 percentage points) per month in care gap closure through any means and 1.6 percentage points (95% CI, 1.4-1.8 percentage points) per month in closure through LDCT. In period 2, introduction of patient-facing reminders was associated with an immediate increase in care gap closure (2.3 percentage points; 95% CI, 1.0-3.6 percentage points) and closure through LDCT (2.4 percentage points; 95% CI, 0.9-3.9 percentage points) but was not associated with an increase in slope. The overall care gap closure rate was 175 of 1104 patients (15.9%) at the end of the baseline period vs 588 of 1255 patients (46.9%) at the end of period 2. Conclusions and Relevance: In this study, a multifaceted intervention was associated with an improvement in LCS care gap closure. Trial Registration: ClinicalTrials.gov Identifier: NCT04498052.
Assuntos
Detecção Precoce de Câncer , Registros Eletrônicos de Saúde , Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/diagnóstico por imagem , Detecção Precoce de Câncer/métodos , Detecção Precoce de Câncer/estatística & dados numéricos , Feminino , Masculino , Idoso , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X/estatística & dados numéricos , Idoso de 80 Anos ou mais , Sistemas de Apoio a Decisões Clínicas , Utah , Análise de Séries Temporais InterrompidaRESUMO
To examine whether psychosocial needs in diabetes care are associated with carbohydrate counting and if carbohydrate counting is associated with satisfaction with diabetes applications' usability, a randomized crossover trial of 92 adults with type 1 or 2 diabetes requiring insulin therapy tested two top-rated diabetes applications, mySugr and OnTrack Diabetes. Survey responses on demographics, psychosocial needs (perceived competence, autonomy, and connectivity), carbohydrate-counting frequency, and application satisfaction were modeled using mixed-effect linear regressions to test associations. Participants ranged between 19 and 74 years old (mean, 54 years) and predominantly had type 2 diabetes (70%). Among the three tested domains of psychosocial needs, only competence-not autonomy or connectivity-was found to be associated with carbohydrate-counting frequency. No association between carbohydrate-counting behavior and application satisfaction was found. In conclusion, perceived competence in diabetes care is an important factor in carbohydrate counting; clinicians may improve adherence to carbohydrate counting with strategies designed to improve perceived competence. Carbohydrate-counting behavior is complex; its impact on patient satisfaction of diabetes application usability is multifactorial and warrants consideration of patient demographics such as sex as well as application features for automated carbohydrate counting.
Assuntos
Diabetes Mellitus Tipo 1 , Diabetes Mellitus Tipo 2 , Aplicativos Móveis , Adulto , Humanos , Adulto Jovem , Pessoa de Meia-Idade , Idoso , Diabetes Mellitus Tipo 2/terapia , Glicemia , Estudos Cross-OverRESUMO
Cell-cell interactions in the central nervous system play important roles in neurologic diseases. However, little is known about the specific molecular pathways involved, and methods for their systematic identification are limited. Here, we developed a forward genetic screening platform that combines CRISPR-Cas9 perturbations, cell coculture in picoliter droplets, and microfluidic-based fluorescence-activated droplet sorting to identify mechanisms of cell-cell communication. We used SPEAC-seq (systematic perturbation of encapsulated associated cells followed by sequencing), in combination with in vivo genetic perturbations, to identify microglia-produced amphiregulin as a suppressor of disease-promoting astrocyte responses in multiple sclerosis preclinical models and clinical samples. Thus, SPEAC-seq enables the high-throughput systematic identification of cell-cell communication mechanisms.
Assuntos
Anfirregulina , Astrócitos , Comunicação Autócrina , Testes Genéticos , Técnicas Analíticas Microfluídicas , Microglia , Astrócitos/fisiologia , Testes Genéticos/métodos , Ensaios de Triagem em Larga Escala , Técnicas Analíticas Microfluídicas/métodos , Microglia/fisiologia , Anfirregulina/genética , Comunicação Autócrina/genética , Expressão Gênica , HumanosRESUMO
The success story of cisplatin spans over six decades now and yet it continues to be the key player in most chemotherapeutic regimens. Numerous efforts have been made to improve its efficacy, address its shortcomings, and overcome drug resistance. One such strategy is to develop new platinum(IV)-based prodrugs with functionally active ligands to deliver combination therapeutics. This strategy not only enables the drug candidate to access multiple drug targets but also enhances the kinetic inertness of platinum complexes and thereby ensures greater accumulation of active drugs at the target site. We report the synthesis of Platin-C, a platinum(IV)-based cisplatin prodrug tethered to the active component of ancient herbal medicine, curcumin, as one of the axial ligands. This combination complex showed improved chemotherapeutic efficacy in cisplatin resistant A2780/CP70 cell lines compared with the individual components. An amine-terminated biodegradable polymer was suitably functionalized with the triphenylphosphonium (TPP) cation to obtain a mitochondria-directed drug delivery platform. Quantification of Platin-C loading into these NPs using complementary techniques employing curcumin optical properties in high-performance liquid chromatography and platinum-based inductively coupled plasma mass spectrometry evidenced efficacious payload incorporation resulting in functional activities of both the components. Stability studies for a period of one week indicated that the NPs remain stable, enabling substantial loading and controlled release of the prodrug. The targeting nanoparticle (NP) platform was utilized to deliver Platin-C primarily in the mitochondrial network of cancer cells as monitored using confocal microscopy employing the green fluorescence of the curcumin pendant. Our studies showed that amine terminated NPs were relatively less efficient in their ability to target mitochondria despite being positively charged. This re-validated the importance of lipophilic positively charged TPP surface functionalities to successfully target cellular mitochondria. We validated the capabilities of Platin-C and its mitochondria-targeting nanoparticles towards inflicting mitochondria-directed activity in cisplatin-sensitive and cisplatin-resistant cell lines. Furthermore, our studies also demonstrated the effectiveness of Platin-C incorporated targeting NPs in attenuating cellular inflammatory markers by utilizing the curcumin component. This study advances our understanding of the cisplatin prodrug approach to combine chemotherapeutic and inflammatory effects in accessing combinatory pathways.
Assuntos
Antineoplásicos , Curcumina , Nanopartículas , Neoplasias Ovarianas , Pró-Fármacos , Humanos , Feminino , Cisplatino/química , Curcumina/farmacologia , Pró-Fármacos/química , Linhagem Celular Tumoral , Neoplasias Ovarianas/tratamento farmacológico , Platina/química , Mitocôndrias , Nanopartículas/química , Antineoplásicos/químicaRESUMO
Do lymphatic vessels support cancer cells? Or are they vessels that help suppress cancer development? It is known that the lymphatic system is a vehicle for tumor metastasis and that the lymphangiogenic regulator VEGF-C supports the tumor. One such role of VEGF-C is the suppression of the immune response to cancer. The lymphatic system has also been correlated with an increase in interstitial fluid pressure of the tumor microenvironment. On the other hand, lymphatic vessels facilitate immune surveillance to mount an immune response against tumors with the support of VEGF-C. Furthermore, the activation of lymphatic fluid drainage may prove to filter and decrease tumor interstitial fluid pressure. In this review, we provide an overview of the dynamic between lymphatics, cancer, and tumor fluid pressure to suggest that lymphatic vessels may be used as an antitumor therapy due to their capabilities of immune surveillance and fluid pressure drainage. The application of this potential may help to prevent tumor proliferation or increase the efficacy of drugs that target cancer.
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Staphylococcus aureus is a foremost bacterial pathogen responsible for a vast array of human diseases. Staphylococcal superantigens (SAgs) constitute a family of exotoxins from S. aureus that bind directly to major histocompatibility complex (MHC) class II and T cell receptors to drive extensive T cell activation and cytokine release. Although these toxins have been implicated in serious disease, including toxic shock syndrome, the specific pathological mechanisms remain unclear. Herein, we aimed to elucidate how SAgs contribute to pathogenesis during bloodstream infections and utilized transgenic mice encoding human MHC class II to render mice susceptible to SAg activity. We demonstrate that SAgs contribute to S. aureus bacteremia by massively increasing bacterial burden in the liver, and this was mediated by CD4+ T cells that produced interferon gamma (IFN-γ) to high levels in a SAg-dependent manner. Bacterial burdens were reduced by blocking IFN-γ, phenocopying SAg-deletion mutant strains, and inhibiting a proinflammatory response. Infection kinetics and flow cytometry analyses suggested that this was a macrophage-driven mechanism, which was confirmed through macrophage-depletion experiments. Experiments in human cells demonstrated that excessive IFN-γ allowed S. aureus to replicate efficiently within macrophages. This indicates that SAgs promote bacterial survival by manipulating the immune response to inhibit effective clearing of S. aureus Altogether, this work implicates SAg toxins as critical therapeutic targets for preventing persistent or severe S. aureus disease.
Assuntos
Interferon gama/imunologia , Infecções Estafilocócicas/imunologia , Superantígenos/imunologia , Animais , Bacteriemia , Enterotoxinas/imunologia , Exotoxinas/imunologia , Antígenos de Histocompatibilidade Classe II/imunologia , Humanos , Interferon gama/metabolismo , Ativação Linfocitária/imunologia , Macrófagos/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Receptores de Antígenos de Linfócitos T/imunologia , Staphylococcus aureus/patogenicidade , Linfócitos T/imunologia , Fatores de Virulência/imunologiaRESUMO
The deleterious effects of psychological stress on mainstream T lymphocytes are well documented. However, how stress impacts innate-like T cells is unclear. We report that long-term stress surprisingly abrogates both T helper 1 (TH1)- and TH2-type responses orchestrated by invariant natural killer T (iNKT) cells. This is not due to iNKT cell death because these cells are unusually refractory to stress-inflicted apoptosis. Activated iNKT cells in stressed mice exhibit a "split" inflammatory signature and trigger sudden serum interleukin-10 (IL-10), IL-23, and IL-27 spikes. iNKT cell dysregulation is mediated by cell-autonomous glucocorticoid receptor signaling and corrected upon habituation to predictable stressors. Importantly, under stress, iNKT cells fail to potentiate cytotoxicity against lymphoma or to reduce the burden of metastatic melanoma. Finally, stress physically spares mouse mucosa-associated invariant T (MAIT) cells but hinders their TH1-/TH2-type responses. The above findings are corroborated in human peripheral blood and hepatic iNKT/MAIT cell cultures. Our work uncovers a mechanism of stress-induced immunosuppression.
Assuntos
Neoplasias Hepáticas/imunologia , Linfoma/imunologia , Células T Invariantes Associadas à Mucosa/imunologia , Células T Matadoras Naturais/imunologia , Estresse Psicológico/imunologia , Linfócitos T Auxiliares-Indutores/imunologia , Animais , Linhagem Celular Tumoral , Doença Crônica , Corticosterona/farmacologia , Citotoxicidade Imunológica , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Imobilização , Imunidade Inata , Interleucina-10/genética , Interleucina-10/imunologia , Interleucina-23/genética , Interleucina-23/imunologia , Interleucinas/genética , Interleucinas/imunologia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Linfoma/genética , Linfoma/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Transgênicos , Células T Invariantes Associadas à Mucosa/efeitos dos fármacos , Células T Invariantes Associadas à Mucosa/patologia , Células T Matadoras Naturais/efeitos dos fármacos , Células T Matadoras Naturais/patologia , Metástase Neoplásica , Oxidopamina/farmacologia , Transdução de Sinais , Estresse Psicológico/genética , Estresse Psicológico/patologia , Linfócitos T Auxiliares-Indutores/efeitos dos fármacos , Linfócitos T Auxiliares-Indutores/patologia , Equilíbrio Th1-Th2RESUMO
Invariant NKT (iNKT) cells are innate-like T lymphocytes that recognize and respond to glycolipid Ags such as α-galactosylceramide (α-GalCer). This unique property has been exploited in clinical trials for multiple malignancies. While investigating mouse iNKT cell responses to α-GalCer in vivo, we found a dramatically enlarged tissue-resident population surprisingly coexpressing select dendritic cell, NK cell, and B cell markers. Further phenotypic and functional analyses revealed the identity of this B220+CD11c+MHC class II+NK1.1+ population as precursors to mature NK (pre-mNK) cells, which also expressed high levels of proliferation and tissue retention markers but diminished sphingosine-1-phosphate receptor 1, a receptor that facilitates tissue trafficking. Accordingly, FTY720, a sphingosine-1-phosphate receptor 1 antagonist, failed to prevent pre-mNK cells' intrahepatic accumulation. We found iNKT cell-driven expansion of pre-mNK cells to be dependent on IL-12 and IL-18. Although α-GalCer-transactivated pre-mNK cells lost their capacity to process a model tumor Ag, they selectively expressed granzyme A and directly lysed YAC-1 thymoma cells through granule exocytosis. They also contributed to ß2 microglobulin-deficient target cell destruction in vivo. Therefore, α-GalCer treatment skewed pre-mNK cell responses away from an APC-like phenotype and toward killer cell-like functions. Finally, the ability of α-GalCer to reduce the pulmonary metastatic burden of B16-F10 mouse melanoma was partially reversed by in vivo depletion of pre-mNK cells. To our knowledge, our findings shed new light on iNKT cells' mechanism of action and glycolipid-based immunotherapies. Therefore, we introduce pre-mNK cells as a novel downstream effector cell type whose anticancer properties may have been overlooked in previous investigations.
Assuntos
Antígenos de Neoplasias/imunologia , Galactosilceramidas/imunologia , Células Matadoras Naturais/imunologia , Melanoma Experimental/imunologia , Células T Matadoras Naturais/imunologia , Timoma/imunologia , Animais , Antígenos de Neoplasias/genética , Linhagem Celular Tumoral , Cloridrato de Fingolimode/farmacologia , Galactosilceramidas/genética , Imunoterapia , Interleucina-12/genética , Interleucina-12/imunologia , Interleucina-18/genética , Interleucina-18/imunologia , Células Matadoras Naturais/patologia , Melanoma Experimental/genética , Melanoma Experimental/patologia , Melanoma Experimental/terapia , Camundongos , Camundongos Knockout , Células T Matadoras Naturais/patologia , Metástase Neoplásica , Receptores de Esfingosina-1-Fosfato/antagonistas & inibidores , Receptores de Esfingosina-1-Fosfato/genética , Receptores de Esfingosina-1-Fosfato/imunologia , Timoma/genética , Timoma/patologia , Timoma/terapiaRESUMO
Stress is known to impede certain host defense mechanisms, including those governed by conventional T lymphocytes. However, whether innate-like T lymphocytes, such as invariant natural killer T (iNKT) and mucosa-associated invariant T (MAIT) cells, are impacted by stress is unclear. Herein, we report that prolonged psychological stress caused by physical confinement results in robust upregulation of T cell immunoreceptor with immunoglobulin and ITIM domains (TIGIT), an immune checkpoint receptor that controls antitumor and antiviral immune responses. Elevated TIGIT expression was found not only on NK and conventional T cells, but also on iNKT and MAIT cells. Stress-provoked TIGIT upregulation was reversed through treatment with the glucocorticoid receptor (GR) antagonist RU486, but not with 6-hydroxydopamine that induces chemical sympathectomy. A Cre/Lox gene targeting model in which GR was ablated in cells expressing Lck under its proximal promoter revealed that TIGIT upregulation in stressed animals stems from direct GR signaling in T and iNKT cells. In fact, long-term oral administration of exogenous corticosterone (CS) to wild-type C57BL/6 (B6) mice was sufficient to increase TIGIT expression levels on T and iNKT cells. In vitro treatment with CS also potently and selectively upregulated TIGIT, but not CTLA-4 or LAG-3, on mouse iNKT and MAIT hybridomas. These results were recapitulated using primary hepatic iNKT and MAIT cells from wild-type B6 and B6.MAITCAST mice, respectively. Subjecting B6.MAITCAST mice to physical restraint also raised the frequency of TIGIT+ cells among hepatic MAIT cells in a GR-dependent manner. Finally, we found that TIGIT is similarly upregulated in a chronic variable stress model in which animals are exposed to unpredictable heterotypic stressors without developing habituation. Taken together, our findings link, for the first time to our knowledge, GR signaling to TIGIT expression. We propose that glucocorticoid hormones dampen immune responses, in part, by enhancing TIGIT expression across multiple critical subsets of effector lymphocytes, including innate-like T cells. Therefore, TIGIT may constitute an attractive target in immune-enhancing interventions for sustained physiological stress.
Assuntos
Células T Invariantes Associadas à Mucosa/metabolismo , Células T Matadoras Naturais/metabolismo , Receptores Imunológicos/metabolismo , Estresse Psicológico/metabolismo , Animais , Feminino , Ativação Linfocitária , Contagem de Linfócitos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Células T Invariantes Associadas à Mucosa/imunologia , Células T Matadoras Naturais/imunologia , Receptores de Glucocorticoides/metabolismo , Receptores Imunológicos/genética , Receptores Imunológicos/imunologia , Transdução de Sinais , Estresse Psicológico/imunologia , Ativação Transcricional , Regulação para CimaRESUMO
Carboxyfluorescein succinimidyl ester (CFSE)-based in vivo cytotoxicity assays enable sensitive and accurate quantitation of CD8+ cytolytic T lymphocyte (CTL) responses elicited against tumor- and pathogen-derived peptides. They offer several advantages over traditional killing assays. First, they permit the monitoring of CTL-mediated cytotoxicity within architecturally intact secondary lymphoid organs, typically in the spleen. Second, they allow for mechanistic studies during the priming, effector and recall phases of CTL responses. Third, they provide useful platforms for vaccine/drug efficacy testing in a truly in vivo setting. Here, we provide an optimized protocol for the examination of concomitant CTL responses against more than one peptide epitope of a model tumor antigen (Ag), namely, simian virus 40 (SV40)-encoded large T Ag (T Ag). Like most other clinically relevant tumor proteins, T Ag harbors many potentially immunogenic peptides. However, only four such peptides induce detectable CTL responses in C57BL/6 mice. These responses are consistently arranged in a hierarchical order based on their magnitude, which forms the basis for TCD8 "immunodominance" in this powerful system. Accordingly, the bulk of the T Ag-specific TCD8 response is focused against a single immunodominant epitope while the other three epitopes are recognized and responded to only weakly. Immunodominance compromises the breadth of antitumor TCD8 responses and is, as such, considered by many as an impediment to successful vaccination against cancer. Therefore, it is important to understand the cellular and molecular factors and mechanisms that dictate or shape TCD8 immunodominance. The protocol we describe here is tailored to the investigation of this phenomenon in the T Ag immunization model, but can be readily modified and extended to similar studies in other tumor models. We provide examples of how the impact of experimental immunotherapeutic interventions can be measured using in vivo cytotoxicity assays.
Assuntos
Linfócitos T CD8-Positivos/imunologia , Citotoxicidade Imunológica , Imunoensaio/métodos , Epitopos Imunodominantes/imunologia , Neoplasias/imunologia , Animais , Antígenos Virais de Tumores/imunologia , Epitopos de Linfócito T/imunologia , Camundongos Endogâmicos C57BL , Peptídeos/imunologia , Linfócitos T Citotóxicos/imunologiaRESUMO
Retinoblastoma is the most common intraocular cancer in children. While the primary tumor can often be treated by local or systemic chemotherapy, metastatic dissemination is generally resistant to therapy and remains a leading cause of pediatric cancer death in much of the world. In order to identify new therapeutic targets in aggressive tumors, we sequenced RNA transcripts in five snap frozen retinoblastomas which invaded the optic nerve and five which did not. A three-fold increase was noted in mRNA levels of ACVR1C/ALK7, a type I receptor of the TGF-ß family, in invasive retinoblastomas, while downregulation of DACT2 and LEFTY2, negative modulators of the ACVR1C signaling, was observed in most invasive tumors. A two- to three-fold increase in ACVR1C mRNA was also found in invasive WERI Rb1 and Y79 cells as compared to non-invasive cells in vitro. Transcripts of ACVR1C receptor and its ligands (Nodal, Activin A/B, and GDF3) were expressed in six retinoblastoma lines, and evidence of downstream SMAD2 signaling was present in all these lines. Pharmacological inhibition of ACVR1C signaling using SB505124, or genetic downregulation of the receptor using shRNA potently suppressed invasion, growth, survival, and reduced the protein levels of the mesenchymal markers ZEB1 and Snail. The inhibitory effects on invasion, growth, and proliferation were recapitulated by knocking down SMAD2, but not SMAD3. Finally, in an orthotopic zebrafish model of retinoblastoma, a 55% decrease in tumor spread was noted (p = 0.0026) when larvae were treated with 3 µM of SB505124, as compared to DMSO. Similarly, knockdown of ACVR1C in injected tumor cells using shRNA also resulted in a 54% reduction in tumor dissemination in the zebrafish eye as compared to scrambled shRNA control (p = 0.0005). Our data support a role for the ACVR1C/SMAD2 pathway in promoting invasion and growth of retinoblastoma.
Assuntos
Receptores de Ativinas Tipo I/metabolismo , Retinoblastoma/patologia , Transdução de Sinais , Proteína Smad2/metabolismo , Receptores de Ativinas Tipo I/genética , Linhagem Celular Tumoral , Proliferação de Células , Regulação para Baixo , Regulação Neoplásica da Expressão Gênica , Humanos , Invasividade Neoplásica , Metástase Neoplásica , Fenótipo , Proteína Smad2/genéticaRESUMO
Mucosa-associated invariant T (MAIT) cells are unconventional, innate-like T lymphocytes that sense the presence of MHC-related protein 1 (MR1)-restricted ligands and select inflammatory cues. Consequently, they release potent immunomodulatory mediators, including IFN-γ, TNF-α, and/or IL-17. MAIT cells can also be viewed as killer cells. They display several NK cell-associated receptors, carry granules containing cytotoxic effector molecules, and swiftly upregulate perforin and granzymes upon activation. Accordingly, MAIT cells are capable of lysing MR1-expressing cells infected with a variety of pathogenic bacteria in in vitro settings and may also mount cytotoxic responses during microbial infections in vivo. Of note, MAIT cell hyperactivation during certain infections may impede their ability to elicit inflammatory and/or cytotoxic responses to secondary stimuli. In addition, MAIT cells isolated from within and from the margin of tumor masses exhibit diminished functions. We propose that MAIT cell-mediated cytotoxicity can be induced, bolstered, or restored to assist in clearing infections and potentially in reducing tumor loads. In this review, we discuss our current understanding of MAIT cells' lytic functions and highlight the pressing questions that need to be addressed in future investigations. We also offer a picture, however hypothetical at this point, of how harnessing the full cytotoxic potentials of MAIT cells may be a valuable approach in the immunotherapy of infectious and malignant diseases.
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Doenças Transmissíveis/imunologia , Imunidade nas Mucosas/imunologia , Células T Invariantes Associadas à Mucosa/imunologia , Neoplasias/imunologia , Animais , HumanosRESUMO
As Pseudomonas aeruginosa infections are characterized by strong inflammation of infected tissues, anti-inflammatory therapies in combination with antibiotics have been considered for the treatment of associated diseases. Syk tyrosine kinase is an important regulator of inflammatory responses, and its specific inhibition was explored as a therapeutic option in several inflammatory conditions; however, this has not been studied in bacterial infections. We used a model of in vitro infection of human monocytic cell line THP-1 and lung epithelial cell line H292 with both wild-type and flagella-deficient mutant of P. aeruginosa strain K, as well as with clinical isolates from cystic fibrosis patients, to study the effect of a small molecule Syk inhibitor R406 on inflammatory responses induced by this pathogen. One-hour pretreatment of THP-1 cells with 10 µmol/L R406 resulted in a significant downregulation of the expression of the adhesion molecule ICAM-1, pro-inflammatory cytokines TNF-α and IL-1ß, and phosphorylated signaling proteins ERK2, JNK, p-38, and IκBα, as well as significantly decreased TNF-α release by infected H292 cells. The results suggest that Syk is involved in the regulation of inflammatory responses to P. aeruginosa, and R406 may potentially be useful in dampening the damage caused by severe inflammation associated with this infection.
Assuntos
Regulação para Baixo , Inflamação/tratamento farmacológico , Modelos Biológicos , Oxazinas/uso terapêutico , Infecções por Pseudomonas/tratamento farmacológico , Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa/fisiologia , Piridinas/uso terapêutico , Quinase Syk/antagonistas & inibidores , Linhagem Celular , Regulação para Baixo/efeitos dos fármacos , Humanos , Inflamação/complicações , Mediadores da Inflamação/metabolismo , Molécula 1 de Adesão Intercelular/metabolismo , Interleucina-1beta/metabolismo , Oxazinas/farmacologia , Fosforilação/efeitos dos fármacos , Infecções por Pseudomonas/complicações , Pseudomonas aeruginosa/efeitos dos fármacos , Piridinas/farmacologia , Fator de Necrose Tumoral alfa/metabolismoRESUMO
Superantigens (SAgs) are potent exotoxins secreted by Staphylococcus aureus and Streptococcus pyogenes. They target a large fraction of T cell pools to set in motion a "cytokine storm" with severe and sometimes life-threatening consequences typically encountered in toxic shock syndrome (TSS). Given the rapidity with which TSS develops, designing timely and truly targeted therapies for this syndrome requires identification of key mediators of the cytokine storm's initial wave. Equally important, early host responses to SAgs can be accompanied or followed by a state of immunosuppression, which in turn jeopardizes the host's ability to combat and clear infections. Unlike in mouse models, the mechanisms underlying SAg-associated immunosuppression in humans are ill-defined. In this work, we have identified a population of innate-like T cells, called mucosa-associated invariant T (MAIT) cells, as the most powerful source of pro-inflammatory cytokines after exposure to SAgs. We have utilized primary human peripheral blood and hepatic mononuclear cells, mouse MAIT hybridoma lines, HLA-DR4-transgenic mice, MAIThighHLA-DR4+ bone marrow chimeras, and humanized NOD-scid IL-2Rγnull mice to demonstrate for the first time that: i) mouse and human MAIT cells are hyperresponsive to SAgs, typified by staphylococcal enterotoxin B (SEB); ii) the human MAIT cell response to SEB is rapid and far greater in magnitude than that launched by unfractionated conventional T, invariant natural killer T (iNKT) or γδ T cells, and is characterized by production of interferon (IFN)-γ, tumor necrosis factor (TNF)-α and interleukin (IL)-2, but not IL-17A; iii) high-affinity MHC class II interaction with SAgs, but not MHC-related protein 1 (MR1) participation, is required for MAIT cell activation; iv) MAIT cell responses to SEB can occur in a T cell receptor (TCR) Vß-specific manner but are largely contributed by IL-12 and IL-18; v) as MAIT cells are primed by SAgs, they also begin to develop a molecular signature consistent with exhaustion and failure to participate in antimicrobial defense. Accordingly, they upregulate lymphocyte-activation gene 3 (LAG-3), T cell immunoglobulin and mucin-3 (TIM-3), and/or programmed cell death-1 (PD-1), and acquire an anergic phenotype that interferes with their cognate function against Klebsiella pneumoniae and Escherichia coli; vi) MAIT cell hyperactivation and anergy co-utilize a signaling pathway that is governed by p38 and MEK1/2. Collectively, our findings demonstrate a pathogenic, rather than protective, role for MAIT cells during infection. Furthermore, we propose a novel mechanism of SAg-associated immunosuppression in humans. MAIT cells may therefore provide an attractive therapeutic target for the management of both early and late phases of severe SAg-mediated illnesses.
Assuntos
Antígenos de Bactérias/toxicidade , Anergia Clonal , Modelos Imunológicos , Células T Invariantes Associadas à Mucosa/imunologia , Staphylococcus aureus/imunologia , Streptococcus pyogenes/imunologia , Superantígenos/toxicidade , Animais , Antígenos de Bactérias/metabolismo , Células da Medula Óssea/citologia , Células da Medula Óssea/efeitos dos fármacos , Células da Medula Óssea/imunologia , Células da Medula Óssea/metabolismo , Linhagem Celular , Células Cultivadas , Anergia Clonal/efeitos dos fármacos , Cruzamentos Genéticos , Enterotoxinas/metabolismo , Enterotoxinas/toxicidade , Feminino , Humanos , Hibridomas , Imunidade Inata , Leucócitos Mononucleares/citologia , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/metabolismo , Ativação Linfocitária/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos NOD , Camundongos Knockout , Camundongos SCID , Camundongos Transgênicos , Células T Invariantes Associadas à Mucosa/citologia , Células T Invariantes Associadas à Mucosa/efeitos dos fármacos , Células T Invariantes Associadas à Mucosa/metabolismo , Organismos Livres de Patógenos Específicos , Staphylococcus aureus/metabolismo , Streptococcus pyogenes/metabolismo , Superantígenos/metabolismo , Quimeras de Transplante/sangue , Quimeras de Transplante/imunologia , Quimeras de Transplante/metabolismoRESUMO
BACKGROUND: A device was devised which aimed to reduce the time and expertise required to perform sonoporation on adherent cell cultures. This prototype device was used to examine the superficial effect of bath temperature on sonoporation efficacy. METHODS: The prototype device consisted of six ultrasound transducers affixed beneath an Opticell stage. Six transducers with nominal diameters of 20 mm were constructed and the acoustic field of each was characterized using hydrophone scanning. A near field treatment plane was chosen for each transducer to minimize field heterogeneity in the near field. Cervical cancer-derived SiHa cells were exposed to nine different treatments in the presence of plasmid DNA-expressing green fluorescent protein (GFP). Ultrasound treatment with Definity ultrasound contrast agent (US+UCA) present, ultrasound treatment without contrast agent present (US), and a sham ultrasound treatment in the presence of ultrasound contrast agent (CA) were each performed at bath temperatures of 37, 39.5, and 42 °C. Each treatment was performed in biological triplicate. GFP expression and PARP expression following treatment were measured using fluorescent microscopy and digital image processing. Cell detachment was measured using phase contrast microscopy before and after treatment. RESULTS: Mean (± s.d.) transfection rates for the US+UCA treatment were 5.4(±0.92), 5.8(±1.3), and 5.3(±1.1) % at 37, 39.5, and 42 °C, respectively. GFP expression and cell detachment were both significantly affected by the presence of ultrasound contrast agent (p < 0.001, p < 0.001). Neither GFP expression, PARP expression, or detachment differed significantly between bath temperatures. CONCLUSIONS: Bath temperature did not impact the efficacy of sonoporation treatment on SiHa cells in vitro. The prototype device was found to be suitable for performing sonoporation on adherent cell cultures and will reduce the time and expertise required for conducting sonoporation experiments on adherent cell cultures in the future.
RESUMO
Nontypeable Haemophilus influenzae (NTHi), a typical mucosal pathogen largely responsible for respiratory infections and pediatric otitis media, has been increasingly recognized as a significant cause of invasive disease, especially in immunocompromised individuals. Lipooligosaccharide (LOS) is a conserved molecule with an important role in H. influenzae virulence and immune evasion, and it may be considered as a vaccine candidate. However, abilities of H. influenzae LOS to induce protective immune response are poorly understood. The goal of this study was to determine whether antibodies against LOS isolated from H. influenzae strains Eagan, Rd and NTHi 375 are present in the sera of normal individuals. Antigen specific IgG and IgM were studied in sera of 71 and 30 healthy adults, respectively. IgG specific for LOS of all three strains was ubiquitously present in our sample population while IgM specific for Eagan, Rd and NTHi 375 LOS compounds was detected in 37%, 63%, and 40% of samples, respectively. All tested serum samples exhibited bactericidal activity against all three H. influenzae strains; the removal of anti-LOS antibodies from the sera resulted in significant increases in bacterial survival of the corresponding strain. NTHi 375 exhibited the highest serum resistance, whereas the Rd strain was the least resistant. Serum bactericidal activity of anti-LOS antibody was mediated via the classical complement pathway. These findings suggest that in healthy adults, naturally acquired complement-activating anti-LOS antibodies significantly contribute to the overall serum bactericidal activity against both encapsulated and non-encapsulated strains of H. influenzae.
Assuntos
Anticorpos Antibacterianos/sangue , Antígenos de Bactérias/imunologia , Haemophilus influenzae/imunologia , Lipopolissacarídeos/imunologia , Vigilância da População , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Fator Ativador de Células B/genética , Fator Ativador de Células B/metabolismo , Atividade Bactericida do Sangue , Linhagem Celular , Expressão Gênica , Infecções por Haemophilus/sangue , Infecções por Haemophilus/imunologia , Infecções por Haemophilus/prevenção & controle , Humanos , Soros Imunes/imunologia , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Pessoa de Meia-Idade , Membro 13 da Superfamília de Ligantes de Fatores de Necrose Tumoral/genética , Membro 13 da Superfamília de Ligantes de Fatores de Necrose Tumoral/metabolismo , Adulto JovemRESUMO
A Gram-negative pathogen Haemophilus influenzae has a truncated endotoxin known as lipooligosaccharide (LOS). Recent studies on H. influenzae LOS highlighted its structural and compositional implications for bacterial virulence; however, the role of LOS in the activation of innate and adaptive immunity is poorly understood. THP-1 monocytes were stimulated with either lipopolysaccharide (LPS) from Escherichia coli or LOS compounds derived from H. influenzae Eagan, Rd, and Rd lic1 lpsA strains. Cell surface expression of key antigen-presenting, costimulatory, and adhesion molecules, as well as gene expression of some cytokines and pattern recognition receptors, were studied. Eagan and Rd LOS had a lower capacity to induce the expression of ICAM-1, CD40, CD58, tumor necrosis factor alpha (TNF-α), and interleukin-1ß (IL-1ß) compared to LPS. In contrast, antigen-presenting (HLA-ABC or HLA-DR) and costimulatory (CD86) molecules and NOD2 were similarly upregulated in response to LOS and LPS. LOS from a mutant Rd strain (Rd lic1 lpsA) consistently induced higher expression of innate immune molecules than the wild-type LOS, suggesting the importance of phosphorylcholine and/or oligosaccharide extension in cellular responses to LOS. An LOS compound with a strong ability to upregulate antigen-presenting and costimulatory molecules combined with a low proinflammatory activity may be considered a vaccine candidate to immunize against H. influenzae.
Assuntos
Haemophilus influenzae/imunologia , Imunidade Inata , Lipopolissacarídeos/imunologia , Antígenos CD/análise , Linhagem Celular , Citocinas/análise , Escherichia coli/imunologia , Perfilação da Expressão Gênica , Antígenos HLA/análise , Humanos , Molécula 1 de Adesão Intercelular/análise , Monócitos/efeitos dos fármacos , Monócitos/imunologia , Proteína Adaptadora de Sinalização NOD2/análise , Receptores Imunológicos/análiseRESUMO
Cancer-associated inflammation induces tumor progression to the metastatic stage, thus indicating that a chemo-anti-inflammatory strategy is of interest for the management of aggressive cancers. The platinum(IV) prodrug Platin-A was designed to release cisplatin and aspirin to ameliorate the nephrotoxicity and ototoxicity caused by cisplatin. Platin-A exhibited anticancer and anti-inflammatory properties which are better than a combination of cisplatin and aspirin. These findings highlight the advantages of combining anti-inflammatory treatment with chemotherapy when both the drugs are delivered in the form of a single prodrug.
Assuntos
Aspirina/administração & dosagem , Cisplatino/administração & dosagem , Pró-Fármacos/administração & dosagem , Administração Intravenosa , Aspirina/química , Aspirina/farmacocinética , Cisplatino/química , Cisplatino/farmacocinética , Humanos , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Pró-Fármacos/química , Pró-Fármacos/farmacocinéticaRESUMO
Site directed drug delivery with high efficacy is the biggest challenge in the area of current pharmaceuticals. Biodegradable polymer-based controlled release nanoparticle platforms could be beneficial for targeted delivery of therapeutics and contrast agents for a myriad of important human diseases. Biodegradable nanoparticles, which can be engineered to load multiple drugs with varied physicochemical properties, contrast agents, and cellular or intracellular component targeting moieties, have emerged as potential alternatives for tracking and treating human diseases. In this review, we will highlight the current advances in the design and execution of such platforms for their potential application in the diagnosis and treatment of variety of diseases ranging from cancer to Alzheimer's and we will provide a critical analysis of the associated challenges for their possible clinical translation.
Assuntos
Portadores de Fármacos/química , Nanopartículas/química , Antineoplásicos/administração & dosagem , Antineoplásicos/química , Materiais Biocompatíveis/química , Barreira Hematoencefálica/química , Barreira Hematoencefálica/metabolismo , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/tratamento farmacológico , Meios de Contraste/administração & dosagem , Meios de Contraste/química , Humanos , Neoplasias/diagnóstico , Neoplasias/tratamento farmacológico , Doenças Neurodegenerativas/diagnóstico , Doenças Neurodegenerativas/tratamento farmacológico , Polímeros/químicaRESUMO
A therapeutic technology that combines the phototoxic and immune-stimulating ability of photodynamic therapy (PDT) with the widespread effectiveness of the immune system can be very promising to treat metastatic breast cancer. We speculated that the knowledge of molecular mechanisms of existing multi-component therapies could provide clues to aid the discovery of new combinations of an immunostimulant with a photosensitizer (PS) using a nanoparticle (NP) delivery platform. Therapeutic challenges when administering therapeutic combinations include the choice of dosages to reduce side effects, the definitive delivery of the correct drug ratio, and exposure to the targets of interest. These factors are very difficult to achieve when drugs are individually administered. By combining controlled release polymer-based NP drug delivery approaches, we were able to differentially deliver zinc phthalocyanine (ZnPc) based PS to metastatic breast cancer cells along with CpG-ODN, a single-stranded DNA that is a known immunostimulant to manage the distant tumors in a temporally regulated manner. We encapsulated ZnPc which is a long-wavelength absorbing PS within a polymeric NP core made up of poly(d,l-lactic-co-glycolic acid)-b-poly(ethylene glycol) (PLGA-b-PEG). After coating the outside of the polymeric core with gold NPs (AuNPs), we further modified the AuNP surface with CpG-ODN. In vitro cytotoxicity using 4T1 metastatic mouse breast carcinoma cells shows significant photocytotoxicity of the hybrid NPs containing both ZnPc and CpG-ODN after irradiation with a 660 nm LASER light and this activity was remarkably better than either treatment alone. Treatment of mouse bone marrow derived dendritic cells with the PDT-killed 4T1 cell lysate shows that the combination of PDT with a synergistic immunostimulant in a single NP system results in significant immune response, which can be used for the treatment of metastatic cancer.