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In vitro studies have shown that deletion of nef and deleterious mutation in the Nef dimerization interface attenuates HIV replication and associated pathogenesis. Humanized rodents with human immune cells and lymphoid tissues are robust in vivo models for investigating the interactions between HIV and the human immune system. Here, we demonstrate that nef deletion impairs HIV replication and HIV-induced immune dysregulation in the blood and human secondary lymphoid tissue (human spleen) in bone marrow-liver-thymus-spleen (BLTS) humanized mice. Furthermore, we also show that nef defects (via deleterious mutations in the dimerization interface) impair HIV replication and HIV-induced immune dysregulation in the blood and human spleen in BLTS-humanized mice. We demonstrate that the reduced replication of nef-deleted and nef-defective HIV is associated with robust antiviral innate immune response, and T helper 1 response. Our results support the proposition that Nef may be a therapeutic target for adjuvants in HIV cure strategies.
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Modelos Animais de Doenças , Infecções por HIV , HIV-1 , Fígado , Baço , Viremia , Replicação Viral , Produtos do Gene nef do Vírus da Imunodeficiência Humana , Animais , Produtos do Gene nef do Vírus da Imunodeficiência Humana/genética , Produtos do Gene nef do Vírus da Imunodeficiência Humana/imunologia , Infecções por HIV/imunologia , Infecções por HIV/virologia , Camundongos , Humanos , Viremia/imunologia , Baço/imunologia , Baço/virologia , HIV-1/imunologia , HIV-1/genética , HIV-1/fisiologia , Fígado/virologia , Fígado/imunologia , Fígado/patologia , Medula Óssea/virologia , Medula Óssea/imunologia , Timo/imunologia , Timo/virologia , Imunidade InataRESUMO
The catecholamine neurotransmitter dopamine is classically known for regulation of central nervous system (CNS) functions such as reward, movement, and cognition. Increasing evidence also indicates that dopamine regulates critical functions in peripheral organs and is an important immunoregulatory factor. We have previously shown that dopamine increases NF-κB activity, inflammasome activation, and the production of inflammatory cytokines such as IL-1ß in human macrophages. As myeloid lineage cells are central to the initiation and resolution of acute inflammatory responses, dopamine-mediated dysregulation of these functions could both impair the innate immune response and exacerbate chronic inflammation. However, the exact pathways by which dopamine drives myeloid inflammation are not well defined, and studies in both rodent and human systems indicate that dopamine can impact the production of inflammatory mediators through both D1-like dopamine receptors (DRD1, DRD5) and D2-like dopamine receptors (DRD2, DRD3, and DRD4). Therefore, we hypothesized that dopamine-mediated production of IL-1ß in myeloid cells is regulated by the ratio of different dopamine receptors that are activated. Our data in primary human monocyte-derived macrophages (hMDM) indicate that DRD1 expression is necessary for dopamine-mediated increases in IL-1ß, and that changes in the expression of DRD2 and other dopamine receptors can alter the magnitude of the dopamine-mediated increase in IL-1ß. Mature hMDM have a high D1-like to D2-like receptor ratio, which is different relative to monocytes and peripheral blood mononuclear cells (PBMCs). We further confirm in human microglia cell lines that a high ratio of D1-like to D2-like receptors promotes dopamine-induced increases in IL-1ß gene and protein expression using pharmacological inhibition or overexpression of dopamine receptors. RNA-sequencing of dopamine-treated microglia shows that genes encoding functions in IL-1ß signaling pathways, microglia activation, and neurotransmission increased with dopamine treatment. Finally, using HIV as an example of a chronic inflammatory disease that is substantively worsened by comorbid substance use disorders (SUDs) that impact dopaminergic signaling, we show increased effects of dopamine on inflammasome activation and IL-1ß in the presence of HIV in both human macrophages and microglia. These data suggest that use of addictive substances and dopamine-modulating therapeutics could dysregulate the innate inflammatory response and exacerbate chronic neuroimmunological conditions like HIV. Thus, a detailed understanding of dopamine-mediated changes in inflammation, in particular pathways regulating IL-1ß, will be critical to effectively tailor medication regimens.
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[This corrects the article DOI: 10.7759/cureus.50541.].
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OBJECTIVE: To compare the digital method and the conventional method of teaching surgical pathology to medical students. METHODS: A prospective case-control study was conducted on second-year students during the period of August 20, 2022, through January 15, 2023. Students, divided into two groups of 45 each, were taught surgical pathology via both conventional and digital methods. Four specimens and four slides were taught in total to the same set of students. A pre-test and a post-test were used to evaluate students' performance and the impact of the teaching method. The answers were analyzed using a paired t-test. In the end, students' responses were obtained regarding their views on a better method of teaching on a Likert scale. RESULTS: To study gross pathology, 50.7% of students were in favor of the digital method, and 21% were not in favor. For the microscopic examination of tissues, 56.92% of students were in favor of the digital method, and 15% were not in favor. There was a significant increase in post-test scores (12.54-9.79 = 2.75, p=0.007) when digital methods for teaching surgical pathology were applied. CONCLUSION: The Likert scale demonstrated that the digital method of teaching surgical pathology not only improved student performance but also resulted in a better understanding of the subject.
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Engineered cytokine-based approaches for immunotherapy of cancer are poised to enter the clinic, with IL-12 being at the forefront. However, little is known about potential mechanisms of resistance to cytokine therapies. We found that orthotopic murine lung tumors were resistant to systemically delivered IL-12 fused to murine serum albumin (MSA, IL12-MSA) because of low IL-12 receptor (IL-12R) expression on tumor-reactive CD8+ T cells. IL2-MSA increased binding of IL12-MSA by tumor-reactive CD8+ T cells, and combined administration of IL12-MSA and IL2-MSA led to enhanced tumor-reactive CD8+ T cell effector differentiation, decreased numbers of tumor-infiltrating CD4+ regulatory T cells, and increased survival of lung tumor-bearing mice. Predictably, the combination of IL-2 and IL-12 at therapeutic doses led to significant dose-limiting toxicity. Administering IL-12 and IL-2 analogs with preferential binding to cells expressing Il12rb1 and CD25, respectively, led to a significant extension of survival in mice with lung tumors while abrogating dose-limiting toxicity. These findings suggest that IL-12 and IL-2 represent a rational approach to combination cytokine therapy whose dose-limiting toxicity can be overcome with engineered cytokine variants.
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Interleucina-12 , Neoplasias Pulmonares , Camundongos , Animais , Interleucina-12/genética , Interleucina-2/genética , Imunoterapia , Citocinas , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/terapiaRESUMO
In the ongoing effort to develop a vaccine against HIV, vaccine approaches that promote strong germinal center (GC) responses may be critical to enable the selection and affinity maturation of rare B cell clones capable of evolving to produce broadly neutralizing antibodies. We previously demonstrated an approach for enhancing GC responses and overall humoral immunity elicited by alum-adjuvanted protein immunization via the use of phosphoserine (pSer) peptide-tagged immunogens that stably anchor to alum particles via ligand exchange with the alum particle surface. Here, using a clinically relevant stabilized HIV Env trimer termed MD39, we systematically evaluated the impact of several parameters relevant to pSer tag composition and trimer immunogen design to optimize this approach, including phosphate valency, amino acid sequence of the trimer C-terminus used for pSer tag conjugation, and structure of the pSer tag. We also tested the impact of co-administering a potent saponin/monophosphoryl lipid A (MPLA) nanoparticle co-adjuvant with alum-bound trimers. We identified MD39 trimer sequences bearing an optimized positively-charged C-terminal amino acid sequence, which, when conjugated to a pSer tag with four phosphates and a polypeptide spacer, bound very tightly to alum particles while retaining a native Env-like antigenicity profile. This optimized pSer-trimer design elicited robust antigen-specific GC B cell and serum IgG responses in mice. Through this optimization, we present a favorable MD39-pSer immunogen construct for clinical translation.
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Coronary allograft vasculopathy, often known as cardiac allograft vasculopathy (CAV), is a substantial source of morbidity and mortality in people who have had heart transplants. Early detection and monitoring of CAV are crucial for improving outcomes in this population. Although cardiac computed tomography (CT) has emerged as a possible method for finding and evaluating CAV, invasive coronary angiography has long been thought of as the gold standard for recognizing CAV. This study focuses on the utility of cardiac CT for CAV diagnosis and treatment in the post-heart transplant population. It provides an overview of recent studies on the application of cardiac CT in CAV and highlights the advantages and disadvantages of this imaging modality. The potential application of cardiac CT for CAV risk assessment and care is also examined in the study. Overall, the data point to a potential role for cardiac CT in the detection and treatment of CAV in post-heart transplant patients. It enables evaluation of the whole coronary tree and low-radiation, high-resolution imaging of the coronary arteries. Hence, further study is required to determine how best to employ cardiac CT in treating CAV in this group.
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Catalase is an antioxidant enzyme that catalyzes the rapid conversion of hydrogen peroxide to water and oxygen. Use of catalase as a cancer therapeutic has been proposed to reduce oxidative stress and hypoxia in the tumor microenvironment, both activities which are hypothesized to reduce tumor growth. Furthermore, exposing murine tumors to exogenous catalase was previously reported to have therapeutic benefit. We studied the therapeutic effect of tumor-localized catalases with the aim to further elucidate the mechanism of action. To do this, we engineered two approaches to maximize intratumoral catalase exposure: 1) an injected extracellular catalase with enhanced tumor retention, and 2) tumor cell lines that over-express intracellular catalase. Both approaches were characterized for functionality and tested for therapeutic efficacy and mechanism in 4T1 and CT26 murine syngeneic tumor models. The injected catalase was confirmed to have enzyme activity >30,000 U/mg and was retained at the injection site for more than one week in vivo. The engineered cell lines exhibited increased catalase activity and antioxidant capacity, with catalase over-expression that was maintained for at least one week after gene expression was induced in vivo. We did not observe a significant difference in tumor growth or survival between catalase-treated and untreated mice when either approach was used. Finally, bulk RNA sequencing of tumors was performed, comparing the gene expression of catalase-treated and untreated tumors. Gene expression analysis revealed very few differentially expressed genes as a result of exposure to catalase and notably, we did not observe changes consistent with an altered state of hypoxia or oxidative stress. In conclusion, we observe that sustained intratumoral catalase neither has therapeutic benefit nor triggers significant differential expression of genes associated with the anticipated therapeutic mechanism in the subcutaneous syngeneic tumor models used. Given the lack of effect observed, we propose that further development of catalase as a cancer therapeutic should take these findings into consideration.
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Antioxidantes , Neoplasias , Animais , Camundongos , Catalase/genética , Catalase/metabolismo , Antioxidantes/metabolismo , Neoplasias/genética , Estresse Oxidativo , Hipóxia/genética , Peróxido de Hidrogênio/metabolismo , Microambiente TumoralRESUMO
PURPOSE OF REVIEW: In this review, we discuss the evidence that vitamin D affects cardiovascular disease through interventional and observational studies and their corresponding association mechanisms. We also highlight the need for further research to definitively conclude clinical recommendations based on preliminary data and determine the extent to which vitamin D levels may impact the incidence and prognosis of major cardiovascular diseases in the future. RECENT FINDINGS: Cardiovascular disease has long been recognized as the leading cause of morbidity and mortality worldwide, with many risk factors implicated in its pathogenesis. Vitamin D is a risk factor that, despite being known to be crucial for its role in maintaining bone health, also has several extra-skeletal effects due to vitamin D receptors in vascular smooth muscle and cardiomyocytes. Recent studies have documented a significant association between higher vitamin D levels and lower risk of each cardiovascular disease entity; 11 studies between serum vitamin D and heart failure, 7 studies between serum vitamin D and hypertension, 8 studies between serum vitamin D and coronary artery disease, and 5 studies between serum vitamin D and atrial fibrillation. More studies documenting a significant association between increased serum vitamin D and cardiovascular disease are in the context of heart failure compared to hypertension, coronary artery disease, and atrial fibrillation. Conversely, a significant association between increased serum vitamin D and a lower risk of atrial fibrillation is reported in fewer studies compared to the association of vitamin D with other cardiovascular disease entities. Although there is evidence documenting a clear significant association of vitamin D under each category, further research is still needed to definitively conclude the role of vitamin D in cardiovascular disease management.
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Fibrilação Atrial , Doenças Cardiovasculares , Doença da Artéria Coronariana , Insuficiência Cardíaca , Hipertensão , Deficiência de Vitamina D , Humanos , Vitamina D , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/complicações , Doença da Artéria Coronariana/complicações , Doença da Artéria Coronariana/epidemiologia , Deficiência de Vitamina D/complicações , Deficiência de Vitamina D/epidemiologia , Hipertensão/complicações , Fatores de RiscoRESUMO
The neurotransmitter dopamine is a key factor in central nervous system (CNS) function, regulating many processes including reward, movement, and cognition. Dopamine also regulates critical functions in peripheral organs, such as blood pressure, renal activity, and intestinal motility. Beyond these functions, a growing body of evidence indicates that dopamine is an important immunoregulatory factor. Most types of immune cells express dopamine receptors and other dopaminergic proteins, and many immune cells take up, produce, store, and/or release dopamine, suggesting that dopaminergic immunomodulation is important for immune function. Targeting these pathways could be a promising avenue for the treatment of inflammation and disease, but despite increasing research in this area, data on the specific effects of dopamine on many immune cells and disease processes remain inconsistent and poorly understood. Therefore, this review integrates the current knowledge of the role of dopamine in immune cell function and inflammatory signaling across systems. We also discuss the current understanding of dopaminergic regulation of immune signaling in the CNS and peripheral tissues, highlighting the role of dopaminergic immunomodulation in diseases such as Parkinson's disease, several neuropsychiatric conditions, neurologic human immunodeficiency virus, inflammatory bowel disease, rheumatoid arthritis, and others. Careful consideration is given to the influence of experimental design on results, and we note a number of areas in need of further research. Overall, this review integrates our knowledge of dopaminergic immunology at the cellular, tissue, and disease level and prompts the development of therapeutics and strategies targeted toward ameliorating disease through dopaminergic regulation of immunity. SIGNIFICANCE STATEMENT: Canonically, dopamine is recognized as a neurotransmitter involved in the regulation of movement, cognition, and reward. However, dopamine also acts as an immune modulator in the central nervous system and periphery. This review comprehensively assesses the current knowledge of dopaminergic immunomodulation and the role of dopamine in disease pathogenesis at the cellular and tissue level. This will provide broad access to this information across fields, identify areas in need of further investigation, and drive the development of dopaminergic therapeutic strategies.
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Sistema Nervoso Central , Dopamina , Receptores Dopaminérgicos , Humanos , Sistema Nervoso Central/imunologia , Dopamina/imunologia , Neurotransmissores/imunologia , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/metabolismo , Receptores Dopaminérgicos/imunologiaRESUMO
Helicobacter pylori has been reported as a health problem worldwide, affecting a sizable portion of people. Peptic ulcers, gastric cancer, and various extra gastric conditions are associated with this bacterium. The rampant overprescribing of antibiotics has led to the emergence of H. pylori strains resistant to multiple antibiotics, causing a decline in the effectiveness of current treatments. Recently, there has been growing interest in researching alternative treatment options for H. pylori infections that do not respond to initial therapy. Rifabutin, a rifamycin derivative initially designed for tuberculosis treatment and preventing Mycobacterium avium complex infection, has gained attention as a potential rescue medication. It has shown efficacy against H. pylori and the potential to eradicate the bacterium when combined with other antibiotics. This systematic review article focuses on using rifabutin-based regimens as a treatment option after initial treatments have failed. The authors screened literature published in the last five years, between 2017 and 2022, across various search engines and closely examined relevant studies following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) criteria. The search covered a variety of electronic databases and focused on H. pylori gastritis, rifabutin-based treatment plans, and in vivo investigations in healthy individuals. The comprehensive review provides convincing evidence that rifabutin-based regimens are effective rescue treatments for H. pylori infections. Multiple studies in various areas consistently demonstrated high eradication rates, ranging from 70% to 90%, when rifabutin-containing regimens were used. The analysis found that only a tiny percentage of H. pylori strains (1%) were resistant to rifabutin therapy, further supporting the viability of Rifabutin as an alternative when other antibiotics failed to eradicate H. pylori. The cost of Rifabutin is a significant factor that may limit its accessibility, particularly in resource-constrained settings where H. pylori infection is common. Moreover, the potential side effects of Rifabutin, such as hematological problems, rashes, and digestive issues, need to be considered. However, these side effects are typically manageable and can be reduced by combining Rifabutin with other antibiotics. In conclusion, this systematic review provides evidence supporting the effectiveness of regimens derived from Rifabutin in eliminating H. pylori infections after initial therapy failure. Due to the observation that Rifabutin effectively eradicates resistant H. pylori infections, it can be considered a suitable choice for rescue therapy. Rifabutin-containing regimens should be reserved as fourth- or later-line therapy options, considering economic factors, the risk of microbial resistance, potential side effects, and the availability of alternative medications. Future research should focus on optimizing rifabutin-based regimens and investigating combination therapies that have better H. pylori eradication rates while also addressing the problem of resistant strains.
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Protein antigens are often combined with aluminum hydroxide (alum), the most commonly used adjuvant in licensed vaccines; yet the immunogenicity of alum-adjuvanted vaccines leaves much room for improvement. Here, the authors demonstrate a strategy for codelivering an immunostimulatory cytokine, the interleukin IL-21, with an engineered outer domain (eOD) human immunodeficiency virus gp120 Env immunogen eOD, bound together to alum to bolster the humoral immune response. In this approach, the immunogen and cytokine are co-anchored to alum particles via a short phosphoserine (pSer) peptide linker, promoting stable binding to alum and sustained bioavailability following injection. pSer-modified eOD and IL-21 promote enhanced lymphatic drainage and lead to accumulation of the vaccine in B cell follicles in the draining lymph nodes. This in turn promotes enhanced T follicular helper cell priming and robust germinal center responses as well as increased antigen-specific serum IgG titers. This is a general strategy for codelivery of immunostimulatory cytokine with immunogens providing a facile approach to modulate T cell priming and GC reactions toward enhanced protective immunity using the most common clinical vaccine adjuvant.
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Effective antitumor immunity in mice requires activation of the type I interferon (IFN) response pathway. IFNα and IFNß therapies have proven promising in humans, but suffer from limited efficacy and high toxicity. Intratumoral IFN retention ameliorates systemic toxicity, but given the complexity of IFN signaling, it was unclear whether long-term intratumoral retention of type I IFNs would promote or inhibit antitumor responses. To this end, we compared the efficacy of IFNα and IFNß that exhibit either brief or sustained retention after intratumoral injection in syngeneic mouse tumor models. Significant enhancement in tumor retention, mediated by anchoring these IFNs to coinjected aluminum-hydroxide (alum) particles, greatly improved both their tolerability and efficacy. The improved efficacy of alum-anchored IFNs could be attributed to sustained pleiotropic effects on tumor cells, immune cells, and nonhematopoietic cells. Alum-anchored IFNs achieved high cure rates of B16F10 tumors upon combination with either anti-PD-1 antibody or interleukin-2. Interestingly however, these alternative combination immunotherapies yielded disparate T cell phenotypes and differential resistance to tumor rechallenge, highlighting important distinctions in adaptive memory formation for combinations of type I IFNs with other immunotherapies.
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Hidróxido de Alumínio , Imunoterapia , Interferon Tipo I , Compostos de Alúmen/química , Hidróxido de Alumínio/química , Animais , Antineoplásicos/uso terapêutico , Modelos Animais de Doenças , Humanos , Imunoterapia/métodos , Imunoterapia/normas , Interferon Tipo I/química , Interferon Tipo I/uso terapêutico , Interferon-alfa , Interferon beta , Nanopartículas Metálicas/química , Nanopartículas Metálicas/uso terapêutico , CamundongosRESUMO
Gamma-delta (γδ) T cells recognize antigens in a major histocompatibility complex (MHC) independent and have cytotoxic capability. Human immunodeficiency virus (HIV) infection reduces the proportion of the Vδ2 cell subset compared to the Vδ1 cell subset of γδ T cells in the blood in most infected individuals, except for elite controllers. The capacity of Vδ2 T cells to kill HIV-infected targets has been demonstrated in vitro, albeit in vivo confirmatory studies are lacking. Here, we provide the first characterization of γδ T cell-HIV interactions in bone marrow-liver-thymus (BLT) humanized mice and examined the immunotherapeutic potential of Vδ2 T cells in controlling HIV replication in vivo. We demonstrate a reduced proportion of Vδ2 T cells and an increased proportion of Vδ1 T cells in HIV-infected BLT humanized mice, like in HIV-positive individuals. HIV infection in BLT humanized mice also impaired the ex vivo expansion of Vδ2 T cells, like in HIV-positive individuals. Adoptive transfer of activated Vδ2 T cells did not control HIV replication during cell-associated HIV transmission in BLT humanized mice but instead exacerbated viremia, suggesting that Vδ2 T cells may serve as early targets for HIV replication. Our findings demonstrate that BLT humanized mice can model γδ T cell-HIV interactions in vivo.
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Infecções por HIV , Linfócitos Intraepiteliais , Animais , Medula Óssea , Modelos Animais de Doenças , Humanos , Fígado , Camundongos , Receptores de Antígenos de Linfócitos T gama-deltaRESUMO
The immunostimulatory intracellular domains (ICDs) of chimaeric antigen receptors (CARs) are essential for converting antigen recognition into antitumoural function. Although there are many possible combinations of ICDs, almost all current CARs rely on combinations of CD3ð, CD28 and 4-1BB. Here we show that a barcoded library of 700,000 unique CD19-specific CARs with diverse ICDs cloned into lentiviral vectors and transduced into Jurkat T cells can be screened at high throughput via cell sorting and next-generation sequencing to optimize CAR signalling for antitumoural functions. By using this screening approach, we identified CARs with new ICD combinations that, compared with clinically available CARs, endowed human primary T cells with comparable tumour control in mice and with improved proliferation, persistence, exhaustion and cytotoxicity after tumour rechallenge in vitro. The screening strategy can be adapted to other disease models, cell types and selection conditions, and could be used to improve adoptive cell therapies and to expand their utility to new disease indications.
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Neoplasias , Receptores de Antígenos de Linfócitos T/análise , Receptores de Antígenos Quiméricos , Animais , Antígenos CD28/metabolismo , Humanos , Imunoterapia Adotiva , Camundongos , Neoplasias/metabolismo , Receptores de Antígenos Quiméricos/genética , Receptores de Antígenos Quiméricos/metabolismo , Linfócitos TRESUMO
Anti-tumour inflammatory cytokines are highly toxic when administered systemically. Here, in multiple syngeneic mouse models, we show that the intratumoural injection of recombinantly expressed cytokines bound tightly to the common vaccine adjuvant aluminium hydroxide (alum) (via ligand exchange between hydroxyls on the surface of alum and phosphoserine residues tagged to the cytokine by an alum-binding peptide) leads to weeks-long retention of the cytokines in the tumours, with minimal side effects. Specifically, a single dose of alum-tethered interleukin-12 induced substantial interferon-γ-mediated T-cell and natural-killer-cell activities in murine melanoma tumours, increased tumour antigen accumulation in draining lymph nodes and elicited robust tumour-specific T-cell priming. Moreover, intratumoural injection of alum-anchored cytokines enhanced responses to checkpoint blockade, promoting cures in distinct poorly immunogenic syngeneic tumour models and eliciting control over metastases and distant untreated lesions. Intratumoural treatment with alum-anchored cytokines represents a safer and tumour-agnostic strategy to improving local and systemic anticancer immunity.