Strategies to Improve Electrical Conductivity in Metal-Organic Frameworks: A Comparative Study.

Metal-organic frameworks (MOFs), formed by the combination of both inorganic and organic components, have attracted special attention for their tunable porous structures, chemical and functional diversities, and enormous applications in gas storage, catalysis, sensing, etc. Recently, electronic applications of MOFs like electrocatalysis, supercapacitors, batteries, electrochemical sensing, etc., have become a major research topic in MOF chemistry. However, the low electrical conductivity of most MOFs represents a major handicap in the development of these emerging applications. To overcome these limitations, different strategies have been developed to enhance electrical conductivity of MOFs for their implementation in electronic devices. In this review, we outline all these strategies employed to increase the electronic conduction in both intrinsically (framework-modulated) and extrinsically (guests-modulated) conducting MOFs.

Assessing Longitudinal Treatment Efficacies and Alterations in Molecular Markers Associated with Glutamatergic Signaling and Immune Checkpoint Inhibitors in a Spontaneous Melanoma Mouse Model.

Previous work done by our laboratory described the use of an immunocompetent spontaneous melanoma-prone mouse model, TGS (TG-3/SKH-1), to evaluate treatment outcomes using inhibitors of glutamatergic signaling and immune checkpoint for 18 weeks. We showed a significant therapeutic efficacy with a notable sex-biased response in male mice. In this follow-up 18-week study, the dose of the glutamatergic signaling inhibitor was increased (from 1.7 mg/kg to 25 mg/kg), which resulted in improved responses in female mice but not male mice. The greatest reduction in tumor progression was observed in male mice treated with single-agent troriluzole and anti-PD-1. Furthermore, a randomly selected group of mice was removed from treatment after 18 weeks and maintained for up to an additional 48 weeks demonstrating the utility of the TGS mouse model to perform a ≥1-year preclinical therapeutic study in a physiologically relevant tumor-host environment. Digital spatial imaging analyses were performed in tumors and tumor microenvironments across treatment modalities using antibody panels for immune cell types and immune cell activation. The results suggest that immune cell populations and cytotoxic activities of T cells play critical roles in treatment responses in these mice. Examination of a group of molecular protein markers based on the proposed mechanisms of action of inhibitors of glutamatergic signaling and immune checkpoint showed that alterations in expression levels of xCT, γ-H2AX, EAAT2, PD-L1, and PD-1 are likely associated with the loss of treatment responses. These results suggest the importance of tracking changes in molecular markers associated with the mechanism of action of therapeutics over the course of a longitudinal preclinical therapeutic study in spatial and temporal manners.

Seasonal influenza vaccines differentially activate and modulate toll-like receptor expression within the tumor microenvironment.

Toll-like receptors (TLRs) are well-known for their role in cancer development as well as in directing anti-tumor immunity. Because TLRs have also been implicated in the innate recognition of the influenza virus, it was of great interest to investigate the potential TLRs' contribution to the reduction in tumor growth following intratumoral injection of an unadjuvanted influenza vaccine and the lack of antitumor response from an adjuvanted vaccine. In our previous publication, we showed that the unadjuvanted flu vaccine modulates TLR7 expression leading to anti-tumor response in a murine model of melanoma. Here, we show that the unadjuvanted and adjuvanted flu vaccines robustly stimulate different sets of TLRs, TLR3 and TLR7, and TLR4 and TLR9, respectively. In addition, the reduction in tumor growth and improved survival from intratumoral administration of the unadjuvanted vaccine was found to be diminished in TLR7-deficient mice. Finally, we observed that both vaccines have the capacity to modulate TLR expression on both innate and adaptive immune cells. Our findings add to the mechanistic understanding of the parameters that influence tumor outcomes in unadjuvanted and adjuvanted influenza vaccines.

Redefining bioactive small molecules from microbial metabolites as revolutionary anticancer agents.

Cancer treatment remains a significant challenge due to issues such as acquired resistance to conventional therapies and the occurrence of adverse treatment-related toxicities. In recent years, researchers have turned their attention to the microbial world in search of novel and effective drugs to combat this devastating disease. Microbial derived secondary metabolites have proven to be a valuable source of biologically active compounds, which exhibit diverse functions and have demonstrated potential as treatments for various human diseases. The exploration of these compounds has provided valuable insights into their mechanisms of action against cancer cells. In-depth studies have been conducted on clinically established microbial metabolites, unraveling their anticancer properties, and shedding light on their therapeutic potential. This review aims to comprehensively examine the anticancer mechanisms of these established microbial metabolites. Additionally, it highlights the emerging therapies derived from these metabolites, offering a glimpse into the immense potential they hold for anticancer drug discovery. Furthermore, this review delves into approved treatments and major drug candidates currently undergoing clinical trials, focusing on specific molecular targets. It also addresses the challenges and issues encountered in the field of anticancer drug research and development. It also presents a comprehensive exposition of the contemporary panorama concerning microbial metabolites serving as a reservoir for anticancer agents, thereby illuminating their auspicious prospects and the prospect of forthcoming strides in the domain of cancer therapeutics.

Microbial Etiologies of Otitis Media with Resistance Pattern in a Tertiary Care Hospital in North India.

Aim: The study aimed to evaluate the bacterial and fungal profiles in Otitis Media (OM), Acute Otitis Media (AOM), and Chronic Otitis Media (COM) and the sensitivity patterns to antibiotics available in our hospital settings. Materials and Methods: A total of 150 clinically diagnosed cases of OM (AOM or COM) with ear discharge were enrolled. Swabs were cultured for microbial flora. Drug susceptibility testing was conducted using the Kirby-Bauer disc diffusion method. Results: The most common bacteria isolated in AOM was Streptococcus spp., and in COM it was Staphylococcus aureus. Among fungal isolates, Candida albicans dominate. The antimicrobial profile of the organisms revealed maximum sensitivity to Fluoroquinolones. Conclusions: Correct diagnosis and precise antibiotic prescription reduce the load of antibiotic resistance.

Attenuated Dengue virus PV001-DV induces oncolytic tumor cell death and potent immune responses.

BACKGROUND: Viral therapies developed for cancer treatment have classically prioritized direct oncolytic effects over their immune activating properties. However, recent clinical insights have challenged this longstanding prioritization and have shifted the focus to more immune-based mechanisms. Through the potential utilization of novel, inherently immune-stimulating, oncotropic viruses there is a therapeutic opportunity to improve anti-tumor outcomes through virus-mediated immune activation. PV001-DV is an attenuated strain of Dengue virus (DEN-1 #45AZ5) with a favorable clinical safety profile that also maintains the potent immune stimulatory properties characterstic of Dengue virus infection. METHODS: In this study, we utilized in vitro tumor killing and immune multiplex assays to examine the anti-tumor effects of PV001-DV as a potential novel cancer immunotherapy. RESULTS: In vitro assays demonstrated that PV001-DV possesses the ability to directly kill human melanoma cells lines as well as patient melanoma tissue ex vivo. Importantly, further work demonstrated that, when patient peripheral blood mononuclear cells (PBMCs) were exposed to PV001-DV, a substantial induction in the production of apoptotic factors and immunostimulatory cytokines was detected. When tumor cells were cultured with the resulting soluble mediators from these PBMCs, rapid cell death of melanoma and breast cancer cell lines was observed. These soluble mediators also increased dengue virus binding ligands and immune checkpoint receptor, PD-L1 expression. CONCLUSIONS: The direct in vitro tumor-killing and immune-mediated tumor cytotoxicity facilitated by PV001-DV contributes support of its upcoming clinical evaluation in patients with advanced melanoma who have failed prior therapy.

Biological Insight and Recent Advancement in the Treatment of Neuroblastoma.

One of the most frequent solid tumors in children is neuroblastoma, which has a variety of clinical behaviors that are mostly influenced by the biology of the tumor. Unique characteristics of neuroblastoma includes its early age of onset, its propensity for spontaneous tumor regression in newborns, and its high prevalence of metastatic disease at diagnosis in individuals older than 1 year of age. Immunotherapeutic techniques have been added to the previously enlisted chemotherapeutic treatments as therapeutic choices. A groundbreaking new treatment for hematological malignancies is adoptive cell therapy, specifically chimeric antigen receptor (CAR) T cell therapy. However, due to the immunosuppressive nature of the tumor microenvironment (TME) of neuroblastoma tumor, this treatment approach faces difficulties. Numerous tumor-associated genes and antigens, including the MYCN proto-oncogene (MYCN) and disialoganglioside (GD2) surface antigen, have been found by the molecular analysis of neuroblastoma cells. The MYCN gene and GD2 are two of the most useful immunotherapy findings for neuroblastoma. The tumor cells devise numerous methods to evade immune identification or modify the activity of immune cells. In addition to addressing the difficulties and potential advancements of immunotherapies for neuroblastoma, this review attempts to identify important immunological actors and biological pathways involved in the dynamic interaction between the TME and immune system.

Functional characterization of hypothetical proteins from Monkeypox virus.

BACKGROUND: Monkeypox virus is a small, double-stranded DNA virus that causes a zoonotic disease called Monkeypox. The disease has spread from Central and West Africa to Europe and North America and created havoc in some countries all around the world. The complete genome of the Monkeypox virus Zaire-96-I-16 has been sequenced. The viral strain contains 191 protein-coding genes with 30 hypothetical proteins whose structure and function are still unknown. Hence, it is imperative to functionally and structurally annotate the hypothetical proteins to get a clear understanding of novel drug and vaccine targets. The purpose of the study was to characterize the 30 hypothetical proteins through the determination of physicochemical properties, subcellular characterization, function prediction, functional domain prediction, structure prediction, structure validation, structural analysis, and ligand binding sites using Bioinformatics tools. RESULTS: The structural and functional analysis of 30 hypothetical proteins was carried out in this research. Out of these, 3 hypothetical functions (Q8V547, Q8V4S4, Q8V4Q4) could be assigned a structure and function confidently. Q8V547 protein in Monkeypox virus Zaire-96-I-16 is predicted as an apoptosis regulator which promotes viral replication in the infected host cell. Q8V4S4 is predicted as a nuclease responsible for viral evasion in the host. The function of Q8V4Q4 is to prevent host NF-kappa-B activation in response to pro-inflammatory cytokines like TNF alpha or interleukin 1 beta. CONCLUSIONS: Out of the 30 hypothetical proteins of Monkeypox virus Zaire-96-I-16, 3 were annotated using various bioinformatics tools. These proteins function as apoptosis regulators, nuclease, and inhibitors of NF-Kappa-B activator. The functional and structural annotation of the proteins can be used to perform a docking with potential leads to discover novel drugs and vaccines against the Monkeypox. In vivo research can be carried out to identify the complete potential of the annotated proteins.

A Spontaneous Melanoma Mouse Model Applicable for a Longitudinal Chemotherapy and Immunotherapy Study.

Mouse models that reflect human disorders provide invaluable tools for the translation of basic science discoveries to clinical therapies. However, many of these in vivo therapeutic studies are short term and do not accurately mimic patient conditions. In this study, we used a fully immunocompetent, transgenic mouse model, TGS, in which the spontaneous development of metastatic melanoma is driven by the ectopic expression of a normal neuronal receptor, mGluR1, as a model to assess longitudinal treatment response (up to 8 months) with an inhibitor of glutamatergic signaling, troriluzole, which is a prodrug of riluzole, plus an antibody against PD-1, an immune checkpoint inhibitor. Our results reveal a sex-biased treatment response that led to improved survival in troriluzole and/or anti-PD-1-treated male mice that correlated with differential CD8+ T cells and CD11b+ myeloid cell populations in the tumor-stromal interface, supporting the notion that this model is a responsive and tractable system for evaluating therapeutic regimens for melanoma in an immunocompetent setting.

Occupational Stress- Addressing Woes of the Nurses in a Burn Unit.

Occupational stress can leave the nurses drained while caring for patients in the burn unit. This existential-phenomenological study aimed to explore burn unit nurses' lived experiences of occupational stressors and organizational support. Twenty-two nurses working in the burn unit were interviewed. Data were analyzed utilizing Colaizzi's 7-step method. Three themes were generated: stressful work environment; feelings of helplessness; need for organizational support. Nurses reported that organizational support should be available for dealing with the work-related stressors in the burn unit.

Intratumoral Influenza Vaccine Administration Attenuates Breast Cancer Growth and Restructures the Tumor Microenvironment through Sialic Acid Binding of Vaccine Hemagglutinin.

Breast cancer continues to have a high disease burden worldwide and presents an urgent need for novel therapeutic strategies to improve outcomes. The influenza vaccine offers a unique approach to enhance the anti-tumor immune response in patients with breast cancer. Our study explores the intratumoral use of the influenza vaccine in a triple-negative 4T1 mouse model of breast cancer. We show that the influenza vaccine attenuated tumor growth using a three-dose intratumoral regimen. More importantly, prior vaccination did not alter this improved anti-tumor response. Furthermore, we characterized the effect that the influenza vaccine has on the tumor microenvironment and the underlying mechanisms of action. We established that the vaccine facilitated favorable shifts in restructuring the tumor microenvironment. Additionally, we show that the vaccine's ability to bind sialic acid residues, which have been implicated in having oncogenic functions, emerged as a key mechanism of action. Influenza hemagglutinin demonstrated binding ability to breast cancer cells through sialic acid expression. When administered intratumorally, the influenza vaccine offers a promising therapeutic strategy for breast cancer patients by reshaping the tumor microenvironment and modestly suppressing tumor growth. Its interaction with sialic acids has implications for effective therapeutic application and future research.

Systematic review and meta-analysis of human genetic variants contributing to COVID-19 susceptibility and severity.

The COVID-19 pandemic has spawned global health crisis of unprecedented magnitude, claiming millions of lives and pushing healthcare systems in many countries to the brink. Among several factors that contribute to an increased risk of COVID-19 and progression to exacerbated manifestations, host genetic landscape is increasingly being recognized as a critical determinant of susceptibility/resistance to infection and a prognosticator of clinical outcomes in infected individuals. Recently, several case-control association studies investigated the influence of human gene variants on COVID-19 susceptibility and severity to identify the culpable mutations. However, a comprehensive synthesis of the recent advances in COVID-19 host genetics research was lacking, and the inconsistent findings of the association studies required reliable evaluation of the strength of association with greater statistical power. In this study, we embarked on a systematic search of all possible reports of genetic association with COVID-19 till April 07, 2022, and performed meta-analyses of all the genetic polymorphisms that were examined in at least three studies. After identifying a total of 84 studies that investigated the association of 130 polymorphisms in 61 genes, we performed meta-analyses of all the eligible studies. Seven genetic polymorphisms involving 15,550 cases and 444,007 controls were explored for association with COVID-19 susceptibility, of which, ACE1 I/D rs4646994/rs1799752, APOE rs429358, CCR5 rs333, and IFITM3 rs12252 showed increased risk of infection. Meta-analyses of 11 gene variants involving 6702 patients with severe COVID-19 and 8640 infected individuals with non-severe manifestations revealed statistically significant association of ACE2 rs2285666, ACE2 rs2106809, ACE2 rs2074192, AGTR1 rs5186, and TNFA rs1800629 with COVID-19 severity. Overall, our study presents a synthesis of evidence on all the genetic determinants implicated in COVID-19 to date, and provides evidence of correlation between the above polymorphisms with COVID-19 susceptibility and severity.

Perceptions and Perceived Barriers regarding Proning among Nurses of a Tertiary Care Center in India.

Current study was conducted to assess the perception and barriers regarding proning among nurses. 385 nurses were conveniently surveyed using pre-tested tools. 3.9% of nurses "felt like running away" while providing care to the patients in prone position. 93.5% believed that prone position for COVID-19 patients is beneficial in reducing morbidity and that teamwork is required to be effective (96.6%). 93% nurses believed that inadequate staff-patient ratio is a significant barrier for prone positioning. Other barriers were fear of dislodgement of tubings (91.5%), difficulty in providing routine care (87.3%) and inadequate institutional protocol (83.9%). 12.5% were trained regarding proning.

Microbial-Derived Toll-like Receptor Agonism in Cancer Treatment and Progression.

Toll-like receptors (TLRs) are typical transmembrane proteins, which are essential pattern recognition receptors in mediating the effects of innate immunity. TLRs recognize structurally conserved molecules derived from microbes and damage-associated molecular pattern molecules that play an important role in inflammation. Since the first discovery of the Toll receptor by the team of J. Hoffmann in 1996, in Drosophila melanogaster, numerous TLRs have been identified across a wide range of invertebrate and vertebrate species. TLR stimulation leads to NF-κB activation and the subsequent production of pro-inflammatory cytokines and chemokines, growth factors and anti-apoptotic proteins. The expression of TLRs has also been observed in many tumors, and their stimulation results in tumor progression or regression, depending on the TLR and tumor type. The anti-tumoral effects can result from the activation of anti-tumoral immune responses and/or the direct induction of tumor cell death. The pro-tumoral effects may be due to inducing tumor cell survival and proliferation or by acting on suppressive or inflammatory immune cells in the tumor microenvironment. The aim of this review is to draw attention to the effects of TLR stimulation in cancer, the activation of various TLRs by microbes in different types of tumors, and, finally, the role of TLRs in anti-cancer immunity and tumor rejection.

CrkII/Abl phosphorylation cascade is critical for NLRC4 inflammasome activity and is blocked by Pseudomonas aeruginosa ExoT.

Type 3 Secretion System (T3SS) is a highly conserved virulence structure that plays an essential role in the pathogenesis of many Gram-negative pathogenic bacteria, including Pseudomonas aeruginosa. Exotoxin T (ExoT) is the only T3SS effector protein that is expressed in all T3SS-expressing P. aeruginosa strains. Here we show that T3SS recognition leads to a rapid phosphorylation cascade involving Abl / PKCδ / NLRC4, which results in NLRC4 inflammasome activation, culminating in inflammatory responses that limit P. aeruginosa infection in wounds. We further show that ExoT functions as the main anti-inflammatory agent for P. aeruginosa in that it blocks the phosphorylation cascade through Abl / PKCδ / NLRC4 by targeting CrkII, which we further demonstrate to be important for Abl transactivation and NLRC4 inflammasome activation in response to T3SS and P. aeruginosa infection.

Presence of Natural Killer B Cells in Simian Immunodeficiency Virus-Infected Colon That Have Properties and Functions Similar to Those of Natural Killer Cells and B Cells but Are a Distinct Cell Population.

Here, we report the appearance of natural killer B (NKB) cells within the colon during simian immunodeficiency virus (SIV) infection of susceptible monkeys. Using RNA sequencing (RNAseq) and flow cytometry, we show that NKB cells are unique cells with features and functions of both NK and B cells. NKB cells express receptors and ligands found on B cells that are important for (i) antigen presentation; (ii) activities associated with class switching, affinity maturation, and B-cell memory formation in secondary lymphoid follicles; and (iii) antigen recognition. The predominant immunoglobulins (Igs) expressed on NKB cells are IgA, although NKB cells can express surface IgM and IgG. There is dominant lambda expression over the kappa light chain characteristic of mucosal B cells. In addition to B-cell aspects, NKB cells express NK cell activation receptors and Fas ligand. We show in this study that NKB cells express perforin and granzymes and lyse cells in a lytic assay. In addition to NK cell cytolytic function, NKB cells also produce the inflammatory cytokines interferon gamma, tumor necrosis factor alpha, and interleukin-18 (IL-18). Finally, we noted the increased capacity of NKB cells to proliferate compared to NK cells and CD8+ T cells from the SIV-infected colon. The increased proliferation and inflammatory cytokine production may be related to the relatively high expression levels of IL-15 receptor beta, IL-7 receptor, IL-18 receptor, and 41BB relative to the same receptors on CD8 and NK cells. The properties of NKB cells may point to their role in the enhanced inflammation observed in the SIV-infected gut. IMPORTANCE There is low-level but significant mucosal inflammation in the gastrointestinal tract secondary to human immunodeficiency virus (HIV) infection that has long-term consequences for the infected host. This inflammation most likely originates from the immune response that appears as a consequence of HIV. Here, we show in an animal model of HIV that the chronically SIV-infected gut contains cytotoxic natural killer B cells that produce inflammatory cytokines and proliferate during infection.

Exploring Drug Metabolism by the Gut Microbiota: Modes of Metabolism and Experimental Approaches.

Increasing evidence uncovers the involvement of gut microbiota in the metabolism of numerous pharmaceutical drugs. The human gut microbiome harbors 10-100 trillion symbiotic gut microbial bacteria that use drugs as substrates for enzymatic processes to alter host metabolism. Thus, microbiota-mediated drug metabolism can change the conventional drug action course and cause inter-individual differences in efficacy and toxicity, making it vital for drug discovery and development. This review focuses on drug biotransformation pathways and discusses different models for evaluating the role of gut microbiota in drug metabolism. SIGNIFICANCE STATEMENT: This review emphasizes the importance of gut microbiota and different modes of drug metabolism mediated by them. It provides information on in vivo, in vitro, ex vivo, in silico and multi-omics approaches for identifying the role of gut microbiota in metabolism. Further, it highlights the significance of gut microbiota-mediated metabolism in the process of new drug discovery and development as a rationale for safe and efficacious drug therapy.

Bacterial-Based Cancer Therapy (BBCT): Recent Advances, Current Challenges, and Future Prospects for Cancer Immunotherapy.

Currently approximately 10 million people die each year due to cancer, and cancer is the cause of every sixth death worldwide. Tremendous efforts and progress have been made towards finding a cure for cancer. However, numerous challenges have been faced due to adverse effects of chemotherapy, radiotherapy, and alternative cancer therapies, including toxicity to non-cancerous cells, the inability of drugs to reach deep tumor tissue, and the persistent problem of increasing drug resistance in tumor cells. These challenges have increased the demand for the development of alternative approaches with greater selectivity and effectiveness against tumor cells. Cancer immunotherapy has made significant advancements towards eliminating cancer. Our understanding of cancer-directed immune responses and the mechanisms through which immune cells invade tumors have extensively helped us in the development of new therapies. Among immunotherapies, the application of bacteria and bacterial-based products has promising potential to be used as treatments that combat cancer. Bacterial targeting of tumors has been developed as a unique therapeutic option that meets the ongoing challenges of cancer treatment. In comparison with other cancer therapeutics, bacterial-based therapies have capabilities for suppressing cancer. Bacteria are known to accumulate and proliferate in the tumor microenvironment and initiate antitumor immune responses. We are currently well-informed regarding various methods by which bacteria can be manipulated by simple genetic engineering or synthetic bioengineering to induce the production of anti-cancer drugs. Further, bacterial-based cancer therapy (BBCT) can be either used as a monotherapy or in combination with other anticancer therapies for better clinical outcomes. Here, we review recent advances, current challenges, and prospects of bacteria and bacterial products in the development of BBCTs.

Effect of IFN-Y +874 T/A polymorphism on clinical manifestations of dengue: a meta-analysis.

Dengue virus (DENV) is a mosquito-borne RNA virus, which infects nearly 3.97 billion people every year in the tropical and subtropical regions of the world. DENV infections can range from unrecognizable illnesses to a spectrum of clinical manifestations such as dengue fever (DF), and more severe and potentially lethal dengue hemorrhagic fever (DHF). The variability of clinical manifestations induced by DENV can be attributed to a variety of extrinsic and intrinsic factors including virulence of the DENV strains and host genetic factors influencing the immune response. Interferon gamma (IFN-Y) is one of the critical immunomodulators implicated in DENV infection, and recent case-control association studies examined the role of +874 T/A polymorphism (rs2430561) of the IFN-Y gene in dengue clinical outcomes. Since the results of the association studies on DENV infection and IFN-Y +874 T/A polymorphism were inconsistent, we performed a meta-analysis to derive a more precise estimate of the association. Searching the databases until 15 March 2020, we identified five studies with a total of 1412 subjects (582 cases and 830 controls), which were included in this meta-analysis. The pooled odds ratio (ORs) with corresponding 95% confidence intervals (CIs) were calculated to evaluate the strength of the association. Pooled data indicated significant association of the TT genotype with DENV infection (DI), DF, and DHF in the recessive model TT vs AT+AA: OR (DI) = 1.47, 95% CI (1.10-1.97), P = 0.01; OR (DF) = 1.40, 95% CI (1.00-1.94), P = 0.04, OR (DHF) = 1.73, 95% CI (1.05-2.86), P = 0.03, and the genotype contrast TT vs AT: OR (DI) = 1.70, 95% CI (1.18-2.47); P = 0.005, OR (DF) = 1.72, 95% CI (1.12-2.66), P = 0.014, OR (DHF) = 1.76, 95% CI (1.01-3.06), P = 0.046. The genotype contrast AA vs AT showed significant association with the milder form of dengue (DF), OR (DF) = 1.60, 95% CI (1.07-2.41), P = 0.023, but not with the severe form (DHF). Taken together, this meta-analysis indicated that both the homozygous genotypes conferred risk to dengue, albeit with varied clinical outcomes, and revealed a protective role of the heterozygous genotype against DENV infection.