ABSTRACT
The stability of the Great Wall is mainly affected by traffic vibrations and natural hazards, such as strong winds, heavy rainfall, and thunderstorms, which are extremely harmful to the safety of the Great Wall. To determine the impact of the above factors on the Great Wall, a comparative analysis based on MEMS (micro-electro-mechanical system) accelerometer data was conducted between the non-impacts and the impacts of the above factors. An analysis of the relationship between vibration acceleration and each potential hazard based on a visual time series chart was presented using the data of accelerometers, traffic video, meteorology, rainfall, and wind. According to the results, traffic vibration is one of the primary dangerous factors affecting the stability of the Great Wall, Moreover, the intensity of the vibrations increases with the traffic flow. Thunderstorms also influence the stability of the Great Wall, with enhanced thunderstorm excitation resulting in increased vibration displacement. Furthermore, wind load is an influencing factor, with average wind speeds greater than 9 m/s significantly affecting the stability of the Great Wall. Rainfall has no impact on the stability of the Great Wall in the short term. This research can provide important guidance for risk assessment and protection of the Great Wall.
ABSTRACT
PURPOSE OF REVIEW: Deep tissue HIV reservoirs, especially within the central nervous system (CNS), are understudied due to the challenges of sampling brain, spinal cord, and other tissues. Understanding the cellular characteristics and viral dynamics in CNS reservoirs is critical so that HIV cure trials can address them and monitor the direct and indirect effects of interventions. The Last Gift program was developed to address these needs by enrolling altruistic people with HIV (PWH) at the end of life who agree to rapid research autopsy. RECENT FINDINGS: Recent findings from the Last Gift emphasize significant heterogeneity across CNS reservoirs, CNS compartmentalization including differential sensitivity to broadly neutralizing antibodies, and bidirectional migration of HIV across the blood-brain barrier. Our findings add support for the potential of CNS reservoirs to be a source of rebounding viruses and reseeding of systemic sites if they are not targeted by cure strategies. This review highlights important scientific, practical, and ethical lessons learned from the Last Gift program in the context of recent advances in understanding the CNS reservoirs and key knowledge gaps in current research.
Subject(s)
HIV Infections , HIV-1 , Humans , HIV-1/physiology , Central Nervous System , Brain , Blood-Brain BarrierABSTRACT
Glutaraldehyde (GLUT) crosslinked bioprosthetic heart valves (BHVs) might fail due to progressive degradation and calcification. GLUT cannot stabilize glycosaminoglycans (GAGs), which are important for BHVs' life time. In this current study we developed a new BHVs preparation strategy using exogenous hyaluronic acid (HA)/chondroitin sulfate (CS) supplement and sodium trimetaphosphate (STP) crosslinking method. Exogenous HA and CS provide additional GAGs for pericardiums. STP could link two GAGs by reacting with hydroxyl groups in GAGs' repeating polysaccharides units. The feeding ratios of HA/CS were optimized. The GAGs content and long-term stability in vitro, biocompatibility, the in vivo GAGs stability and anti-calcification potential of GLUT/HA/CS and STP treated pericardiums were characterized. We demonstrated that GLUT/HA/CS and STP treated pericardiums had sufficiently increased GAGs' amount and stability and decreased calcification. This new exogenous hyaluronic acid/chondroitin sulfate supplement and sodium trimetaphosphate crosslinking strategy would be a promising method to make BHVs with better structural stability and anti-calcification properties.
Subject(s)
Bioprosthesis , Chondroitin Sulfates/chemistry , Cross-Linking Reagents/chemistry , Glycosaminoglycans/chemistry , Heart Valve Prosthesis , Hyaluronic Acid/chemistry , Animals , Aortic Valve/surgery , Biocompatible Materials , Blood Coagulation , Glutaral/chemistry , Male , Pericardium/pathology , Platelet Adhesiveness , Polyphosphates/chemistry , Rats , Rats, Sprague-Dawley , Spectrophotometry, Infrared , Sulfates , SwineABSTRACT
Although anti-retroviral therapy (ART) is highly effective in suppressing HIV replication, it fails to eradicate the virus from HIV-infected individuals. Stable latent HIV reservoirs are rapidly established early after HIV infection. Therefore, effective strategies for eradication of the HIV reservoirs are urgently needed. We report that ingenol-3-angelate (PEP005), the only active component in a previously FDA approved drug (PICATO) for the topical treatment of precancerous actinic keratosis, can effectively reactivate latent HIV in vitro and ex vivo with relatively low cellular toxicity. Biochemical analysis showed that PEP005 reactivated latent HIV through the induction of the pS643/S676-PKCδ/θ-IκBα/ε-NF-κB signaling pathway. Importantly, PEP005 alone was sufficient to induce expression of fully elongated and processed HIV RNAs in primary CD4+ T cells from HIV infected individuals receiving suppressive ART. Furthermore, PEP005 and the P-TEFb agonist, JQ1, exhibited synergism in reactivation of latent HIV with a combined effect that is 7.5-fold higher than the effect of PEP005 alone. Conversely, PEP005 suppressed HIV infection of primary CD4+ T cells through down-modulation of cell surface expression of HIV co-receptors. This anti-cancer compound is a potential candidate for advancing HIV eradication strategies.
Subject(s)
Azepines/pharmacology , Diterpenes/pharmacology , HIV Infections/drug therapy , NF-kappa B/metabolism , Signal Transduction/drug effects , Triazoles/pharmacology , Virus Latency/drug effects , Azepines/administration & dosage , Diterpenes/administration & dosage , HIV-1/drug effects , Humans , I-kappa B Proteins/pharmacology , NF-KappaB Inhibitor alpha , Positive Transcriptional Elongation Factor B/metabolism , T-Lymphocytes/drug effects , T-Lymphocytes/metabolism , Triazoles/administration & dosage , Virus Activation/drug effectsABSTRACT
Understanding human immunodeficiency virus type 1 (HIV-1) transmission is central to developing effective prevention strategies, including a vaccine. We compared phenotypic and genetic variation in HIV-1 env genes from subjects in acute/early infection and subjects with chronic infections in the context of subtype C heterosexual transmission. We found that the transmitted viruses all used CCR5 and required high levels of CD4 to infect target cells, suggesting selection for replication in T cells and not macrophages after transmission. In addition, the transmitted viruses were more likely to use a maraviroc-sensitive conformation of CCR5, perhaps identifying a feature of the target T cell. We confirmed an earlier observation that the transmitted viruses were, on average, modestly underglycosylated relative to the viruses from chronically infected subjects. This difference was most pronounced in comparing the viruses in acutely infected men to those in chronically infected women. These features of the transmitted virus point to selective pressures during the transmission event. We did not observe a consistent difference either in heterologous neutralization sensitivity or in sensitivity to soluble CD4 between the two groups, suggesting similar conformations between viruses from acute and chronic infection. However, the presence or absence of glycosylation sites had differential effects on neutralization sensitivity for different antibodies. We suggest that the occasional absence of glycosylation sites encoded in the conserved regions of env, further reduced in transmitted viruses, could expose specific surface structures on the protein as antibody targets.
Subject(s)
Genetic Variation , HIV Infections/metabolism , HIV-1/metabolism , Receptors, CCR5/metabolism , T-Lymphocytes/virology , Viral Envelope Proteins/metabolism , Base Sequence , Cloning, Molecular , Cluster Analysis , Cohort Studies , Female , Glycosylation , HIV Infections/prevention & control , HIV Infections/transmission , Humans , Malawi , Male , Molecular Sequence Data , Neutralization Tests , Phylogeny , Protein Conformation , Receptors, CCR5/chemistry , Sequence Alignment , Sequence Analysis, DNA , Sex Factors , South Africa , T-Lymphocytes/immunology , Viral Envelope Proteins/genetics , Virus Replication/physiologyABSTRACT
RATIONALE: Hyalinizing clear cell carcinoma (HCCC) of the salivary glands is a rare low-grade malignant tumor. This type of tumor is particularly uncommon in the sublingual glands. PATIENT CONCERNS: A 57-year-old female with a mass on the left side of the floor of the mouth that had been present for 2 months. The computed tomography scan of the neck revealed a nodular abnormal density shadow in the left sublingual area, measuring approximately 2.6 cmâ ×â 1.9 cm. DIAGNOSES: Primary HCCC of the sublingual gland. INTERVENTIONS: The patient underwent surgical treatment and reconstruction using a left anterolateral femoral free flap, which showed immunohistochemical positivity for CK 5/6, CK 7, CK (AE1/AE3), and Ki-67 (<5%), but negative for SMA and S-100. OUTCOMES: No recurrence was observed during the 12-month postoperative follow-up period. LESSONS: The absence of characteristic clinical manifestations makes HCCC highly susceptible to misdiagnoses. This case presents a rare instance of HCCC in the sublingual gland, providing a reference for the clinical diagnosis and treatment of the disease.
Subject(s)
Adenocarcinoma, Clear Cell , Sublingual Gland Neoplasms , Humans , Female , Middle Aged , Sublingual Gland Neoplasms/pathology , Sublingual Gland Neoplasms/surgery , Sublingual Gland Neoplasms/diagnosis , Adenocarcinoma, Clear Cell/surgery , Adenocarcinoma, Clear Cell/pathology , Adenocarcinoma, Clear Cell/diagnosis , Tomography, X-Ray Computed , Sublingual Gland/pathology , Sublingual Gland/surgery , Sublingual Gland/diagnostic imagingABSTRACT
BACKGROUND: Oxidative stress plays an important role in the skin aging process. Rapamycin has been shown to have anti-aging effects, but its role in oxidative senescence of skin cells remains unclear. The aim of this study was to explore the effect of rapamycin on oxidative stress-induced skin cell senescence and to illustrate the mechanism. METHODS: Primary human skin fibroblasts (HSFs) were extracted and a model of H2O2-induced oxidative senescence was constructed, and the effects of rapamycin on their value-added and migratory capacities were detected by CCK-8 and scratch assays. SA-ß-gal was utilized to detect senescence, oxidatively closely related factors were also assessed. Gene and protein expressions of senescence, oxidative, and autophagy were detected by western blotting and quantitative-PCR. The data were analyzed by one-way analysis of variance. RESULTS: Rapamycin (0.1 nmol/L for 48 h) promoted the proliferative and migration of H2O2-treated HSFs (p < 0.05), decreased senescent phenotypes SA-ß-gal staining and the expression of P53, and MMP-1 proteins, and increased the expression level of COL1A-1 (p < 0.001). Rapamycin also enhanced the activities of SOD and HO-1, and effectively removed intracellular ROS, MDA levels (p < 0.05), in addition, autophagy-related proteins and genes were significantly elevated after rapamycin pretreatment (p < 0.001). Rapamycin upregulated the autophagy pathway to exert its protective effects. CONCLUSION: Our findings indicate that rapamycin shields HSFs from H2O2-induced oxidative damage, the mechanism is related to the reduction of intracellular peroxidation and upregulation of autophagy pathway. Therefore, rapamycin has the potential to be useful in the investigation and prevention of signs of aging and oxidative stress.
ABSTRACT
Human immunodeficiency virus-1 (HIV) infection is a chronic disease under antiretroviral therapy (ART), during which active HIV replication is effectively suppressed. Stable viral reservoirs are established early in infection and cannot be eradicated in people with HIV (PWH) by ART alone, which features residual immune inflammation with disease-associated secondary comorbidities. Mammalian cells are equipped with integrated stress response (ISR) machinery to detect intrinsic and extrinsic stresses such as heme deficiency, nutrient fluctuation, the accumulation of unfolded proteins, and viral infection. ISR is the part of the innate immunity that defends against pathogen infection or environmental alteration, thereby maintaining homeostasis to avoid diseases. Here, we describe how this machinery responds to the off-target effects of ART and persistent HIV infection in both the peripheral compartments and the brain. The latter may be important for us to better understand the mechanisms of stable HIV reservoirs and HIV-associated neurocognitive disorders.
ABSTRACT
HIV reservoirs are extremely stable and pose a tremendous challenge to clear HIV infection. Here, we demonstrate that activation of ISR/ATF4 signaling reverses HIV latency, which also selectively eliminates HIV+ cells in primary CD4+T cell model of latency without effect on HIV-negative CD4+T cells. The reduction of HIV+ cells is associated with apoptosis enhancement, but surprisingly is largely seen in HIV-infected cells in which gag-pol RNA transcripts are detected in HIV RNA-induced ATF4/IFIT signaling. In resting CD4+ (rCD4+) T cells isolated from people living with HIV on antiretroviral therapy, induction of ISR/ATF4 signaling reduced HIV reservoirs by depletion of replication-competent HIV without global reduction in the rCD4+ T cell population. These findings suggest that compromised ISR/ATF4 signaling maintains stable and quiescent HIV reservoirs whereas activation of ISR/ATF4 signaling results in the disruption of latent HIV and clearance of persistently infected CD4+T cells.
ABSTRACT
Brain microglia (MG) may serve as a human immunodeficiency virus 1 (HIV) reservoir and ignite rebound viremia following cessation of antiretroviral therapy (ART), but they have yet to be proven to harbor replication-competent HIV. Here, we isolated brain myeloid cells (BrMCs) from nonhuman primates and rapid autopsy of people with HIV (PWH) on ART and sought evidence of persistent viral infection. BrMCs predominantly displayed microglial markers, in which up to 99.9% of the BrMCs were TMEM119+ MG. Total and integrated SIV or HIV DNA was detectable in the MG, with low levels of cell-associated viral RNA. Provirus in MG was highly sensitive to epigenetic inhibition. Outgrowth virus from parietal cortex MG in an individual with HIV productively infected both MG and PBMCs. This inducible, replication-competent virus and virus from basal ganglia proviral DNA were closely related but highly divergent from variants in peripheral compartments. Phenotyping studies characterized brain-derived virus as macrophage tropic based on the ability of the virus to infect cells expressing low levels of CD4. The lack of genetic diversity in virus from the brain suggests that this macrophage-tropic lineage quickly colonized brain regions. These data demonstrate that MG harbor replication-competent HIV and serve as a persistent reservoir in the brain.
Subject(s)
HIV Infections , HIV-1 , Animals , Humans , Microglia , Brain , Macrophages , Proviruses/genetics , HIV Infections/drug therapyABSTRACT
HIV-1 is present in anatomical compartments and bodily fluids. Most transmissions occur through sexual acts, making virus in semen the proximal source in male donors. We find three distinct relationships in comparing viral RNA populations between blood and semen in men with chronic HIV-1 infection, and we propose that the viral populations in semen arise by multiple mechanisms including: direct import of virus, oligoclonal amplification within the seminal tract, or compartmentalization. In addition, we find significant enrichment of six out of nineteen cytokines and chemokines in semen of both HIV-infected and uninfected men, and another seven further enriched in infected individuals. The enrichment of cytokines involved in innate immunity in the seminal tract, complemented with chemokines in infected men, creates an environment conducive to T cell activation and viral replication. These studies define different relationships between virus in blood and semen that can significantly alter the composition of the viral population at the source that is most proximal to the transmitted virus.
Subject(s)
HIV Infections/virology , HIV-1/genetics , Semen/virology , Cytokines/biosynthesis , Cytokines/immunology , Genes, env/genetics , HIV Infections/transmission , HIV-1/immunology , Humans , Male , Phylogeny , RNA, Viral/analysis , RNA, Viral/geneticsABSTRACT
Iodinated disinfection by-products (I-DBPs) have attracted extensive interests because of their higher cytotoxicity and genotoxicity than their chlorinated and brominated analogues. Our recent studies have firstly demonstrated that cooking with seaweed salt could enhance the formation of I-DBPs with several tens of µg/L level. Here, I-DBP formation and mitigation from the reaction of disinfectant with Laminaria japonica (Haidai), an edible seaweed with highest iodine content, upon simulated household cooking process was systematically investigated. The total iodine content in Haidai ranged from 4.6 mg-I/g-Haidai to 10.0 mg-I/g-Haidai, and more than 90% of iodine is soluble iodide. During simulated cooking, the presence of disinfectant simultaneously decreased iodide by 15.0-32.8% to 2.7-5.8 mg/L and increased total organic iodine by 1.3-10.9 times to 0.5-1.8 mg/L in Haidai soup, proving I-DBP formation. The concentrations of iodinated trihalomethanes and haloacetic acids were at the levels of several hundreds of µg/L and several µg/L, respectively, which are 2-3 orders and 1-2 orders of magnitude more than those in drinking water. Effects of key factors including disinfectant specie, disinfectant dose, temperature and time on I-DBP formation were also ascertained, and temperature and disinfectant specie played a decisive role in the formation and speciation of I-DBPs. In order to avoid the potential health risk from the exposure of I-DBPs in Haidai soup, it is prerequisite to soak and wash dry Haidai sample over 30.0 min before cooking, which could effectively remove major soluble iodide. In general, this study provided the new insight into I-DBP formation from daily household cooking with Haidai and the corresponding enlightenment for inhabitants to eat Haidai in daily life.
Subject(s)
Disinfectants , Drinking Water , Iodine , Laminaria , Water Pollutants, Chemical , Water Purification , Disinfection , Drinking Water/analysis , Iodides , Halogenation , Water Pollutants, Chemical/analysis , Trihalomethanes/analysis , Disinfectants/analysis , CookingABSTRACT
Human Immunodeficiency Virus-1 (HIV) remains a global health challenge due to the latent HIV reservoirs in people living with HIV (PLWH). Dormant yet replication competent HIV harbored in the resting CD4+ T cells cannot be purged by antiretroviral therapy (ART) alone. One approach of HIV cure is the "Kick and Kill" strategy where latency reversal agents (LRAs) have been implemented to disrupt latent HIV, expecting to eradicate HIV reservoirs by viral cytopathic effect or immune-mediated clearance. Protein Kinase C agonists (PKCa), a family of LRAs, have demonstrated the ability to disrupt latent HIV to an extent. However, the toxicity of PKCa remains a concern in vivo. Early growth response protein 1 (EGR1) is a downstream target of PKCa during latency reversal. Here, we show that PKCa induces EGR1 which directly drives Tat-dependent HIV transcription. Resveratrol, a natural phytoalexin found in grapes and various plants, induces Egr1 expression and disrupts latent HIV in several HIV latency models in vitro and in CD4+ T cells isolated from ART-suppressed PLWH ex vivo. In the primary CD4+ T cells, resveratrol does not induce immune activation at the dosage that it reverses latency, indicating that targeting EGR1 may be able to reverse latency and bypass PKCa-induced immune activation.
ABSTRACT
Adeno-associated virus (AAV)-mediated genetic targeting of microglia remains a challenge. Overcoming this hurdle is essential for gene editing in the central nervous system (CNS). Here, we characterized the minimal/native promoter of the HEXB gene, which is known to be specifically and stably expressed in the microglia during homeostatic and pathological conditions. Dual reporter and serial deletion assays identified the critical role of the natural 5' untranslated region (-97 bp related to the first ATG) in driving transcriptional activity of the mouse Hexb gene. The native promoter region of mouse, human, and monkey HEXB are located at -135, -134, and -170 bp to the first ATG, respectively. These promoters were highly active and specific in microglia with strong cross-species transcriptional activities, but did not exhibit activity in primary astrocytes. In addition, we identified a 135 bp promoter of CD68 gene that was highly active in microglia but not in astrocytes. Considering that HEXB is specifically expressed in microglia, these data suggest that the newly characterized microglia-specific HEXB minimal/native promoter can be an ideal candidate for microglia-targeting AAV gene therapy in the CNS.
ABSTRACT
The eradication of HIV infection is difficult to achieve because of stable viral reservoirs. Here, we show that crotonylation enhances AZD5582-induced noncanonical NF-κB (ncNF-κB) signaling, further augmenting HIV latency reversal in Jurkat and U1 cell line models of latency, HIV latently infected primary CD4+ T cells and resting CD4+ T cells isolated from people living with HIV. Crotonylation upregulated the levels of the active p52 subunit of NF-κB following AZD5582. Biochemical analyses suggest that the ubiquitin E3 ligase TRIM27 is involved in enhanced p100 cleavage to p52. When TRIM27 was depleted, AZD5582-induced HIV latency reversal was reduced. TRIM27 small interfering RNA (siRNA) knockdown reduced both p100 and p52 levels without inhibiting p100 transcription, indicating that TRIM27 not only acts on p100 cleavage but also may impact p100/p52 stability. These observations reveal the complexity of HIV transcriptional machinery, particularly of NF-κB.
ABSTRACT
Human immunodeficiency virus type 1 (HIV-1) relies on cholesterol-laden lipid raft membrane microdomains for entry into and egress out of susceptible cells. In the present study, we examine the need for intracellular cholesterol trafficking pathways with respect to HIV-1 biogenesis using Niemann-Pick type C-1 (NPC1)-deficient (NPCD) cells, wherein these pathways are severely compromised, causing massive accumulation of cholesterol in late endosomal/lysosomal (LE/L) compartments. We have found that induction of an NPC disease-like phenotype through treatment of various cell types with the commonly used hydrophobic amine drug U18666A resulted in profound suppression of HIV-1 release. Further, NPCD Epstein-Barr virus-transformed B lymphocytes and fibroblasts from patients with NPC disease infected with a CD4-independent strain of HIV-1 or transfected with an HIV-1 proviral clone, respectively, replicated HIV-1 poorly compared to normal cells. Infection of the NPCD fibroblasts with a vesicular stomatitis virus G-pseudotyped strain of HIV-1 produced similar results, suggesting a postentry block to HIV-1 replication in these cells. Examination of these cells using confocal microscopy showed an accumulation and stabilization of Gag in LE/L compartments. Additionally, normal HIV-1 production could be restored in NPCD cells upon expression of a functional NPC1 protein, and overexpression of NPC1 increased HIV-1 release. Taken together, our findings demonstrate that intact intracellular cholesterol trafficking pathways mediated by NPC1 are needed for efficient HIV-1 production.
Subject(s)
Endosomes/metabolism , HIV Infections/metabolism , HIV-1/physiology , Lysosomes/metabolism , Membrane Glycoproteins/deficiency , Niemann-Pick Diseases/metabolism , gag Gene Products, Human Immunodeficiency Virus/metabolism , Carrier Proteins/genetics , Cell Line , Cells, Cultured , Cholesterol/metabolism , Endosomes/genetics , Fibroblasts/metabolism , HIV Infections/complications , HIV Infections/virology , HIV-1/genetics , Humans , Intracellular Signaling Peptides and Proteins , Lysosomes/genetics , Membrane Glycoproteins/genetics , Niemann-Pick C1 Protein , Niemann-Pick Diseases/complications , Niemann-Pick Diseases/virology , gag Gene Products, Human Immunodeficiency Virus/geneticsABSTRACT
Radical cure of HIV-1 (HIV) is hampered by the establishment of HIV reservoirs and persistent infection in deep tissues despite suppressive antiretroviral therapy (ART). Here, we show that among HIV-positive women receiving suppressive ART, cells from placental tissues including trophoblasts contain HIV RNA and DNA. These viruses can be reactivated by latency reversal agents. We find that syncytin, the envelope glycoprotein of human endogenous retrovirus family W1 expressed on placental trophoblasts, triggers cell fusion with HIV-infected T cells. This results in cell-to-cell spread of HIV to placental trophoblasts. Such cell-to-cell spread of HIV is less sensitive to ART than free virus. Replication in syncytin-expressing cells can also produce syncytin-pseudotyped HIV, further expanding its ability to infect non-CD4 cells. These previously unrecognized mechanisms of HIV entry enable the virus to bypass receptor restriction to infect host barrier cells, thereby facilitating viral transmission and persistent infection in deep tissues.
Subject(s)
Disease Reservoirs/virology , Endogenous Retroviruses/metabolism , Gene Products, env/metabolism , Placenta/virology , Pregnancy Proteins/metabolism , Viral Envelope Proteins/metabolism , Adult , Antiretroviral Therapy, Highly Active , CD4-Positive T-Lymphocytes/virology , Cell Fusion , DNA, Viral/genetics , Female , HIV Infections/drug therapy , HIV Infections/immunology , HIV Infections/virology , HIV-1/genetics , HeLa Cells , Host-Pathogen Interactions , Humans , Pregnancy , Proviruses/metabolism , RNA, Viral/metabolism , Tissue Donors , Trophoblasts/pathology , Trophoblasts/virology , Tropism , Viral LoadABSTRACT
Latent HIV reservoir is the main obstacle that prevents a cure for HIV-1 (HIV). While antiretroviral therapy is effective in controlling viral replication, it cannot eliminate latent HIV reservoirs in patients. Several strategies have been proposed to combat HIV latency, including bone marrow transplantation to replace blood cells with CCR5-mutated stem cells, gene editing to disrupt the HIV genome, and "Shock and Kill" to reactivate latent HIV followed by an immune clearance. However, high risks and limitations to scale-up in clinics, off-target effects in human genomes or failure to reduce reservoir sizes in patients hampered our current efforts to achieve an HIV cure. This necessitates alternative strategies to control the latent HIV reservoirs. This review will discuss an emerging strategy aimed to deeply silence HIV reservoirs, the development of this concept, its potential and caveats for HIV remission/cure, and prospective directions for silencing the latent HIV, thereby preventing viruses from rebound.
Subject(s)
Disease Reservoirs/virology , HIV Infections/genetics , HIV-1/genetics , Virus Latency/genetics , CD4-Positive T-Lymphocytes/virology , HIV Infections/epidemiology , HIV Infections/transmission , HIV Infections/virology , HIV-1/pathogenicity , Humans , Receptors, CCR5/genetics , Virus Activation/genetics , Virus Replication/geneticsABSTRACT
Bioprosthetic heart valves (BHVs) used in the clinic are mostly fixed by glutaraldehyde and the lack of endothelialization is a major problem for glutaraldehyde-fixed pericardia. Hyaluronic acid is a major glycosaminoglycan that exists in native heart valves. Coupled with its inherent biocompatibility, it may enhance endothelial adhesion and proliferation when associated with vascular endothelial growth factor (VEGF). In this study, an optimized system is developed to improve the endothelialization of glutaraldehyde-fixed pericardium. A hybrid pericardium with VEGF-loaded hyaluronic acid hydrogel coating is developed by the crosslinking of 1,4-butanediol diglycidyl ether. The adhesion and growth potential of human umbilical vein endothelial cells (HUVECs) on pericardia, platelet adhesion, and calcification by an in vivo rat subdermal implantation model are investigated. The results show improved HUVEC adhesion and proliferation, less platelet adhesion, and less calcification for hybrid pericardium by introducing the coating of VEGF-loaded hyaluronic acid hydrogel. Thus, the coating of VEGF-loaded hyaluronic acid hydrogel on pericardium is a promising approach to obtain bioprosthetic valves for clinical applications with increased endothelialization and antithrombotic and anticalcification properties.