-
Viruses May 2024The HIV-1 nucleocapsid protein (NC) is a multifunctional viral protein necessary for HIV-1 replication. Recent studies have demonstrated that reverse transcription (RT)...
The HIV-1 nucleocapsid protein (NC) is a multifunctional viral protein necessary for HIV-1 replication. Recent studies have demonstrated that reverse transcription (RT) completes in the intact viral capsid, and the timing of RT and uncoating are correlated. How the small viral core stably contains the ~10 kbp double stranded (ds) DNA product of RT, and the role of NC in this process, are not well understood. We showed previously that NC binds and saturates dsDNA in a non-specific electrostatic binding mode that triggers uniform DNA self-attraction, condensing dsDNA into a tight globule against extending forces up to 10 pN. In this study, we use optical tweezers and atomic force microscopy to characterize the role of NC's basic residues in dsDNA condensation. Basic residue mutations of NC lead to defective interaction with the dsDNA substrate, with the constant force plateau condensation observed with wild-type (WT) NC missing or diminished. These results suggest that NC's high positive charge is essential to its dsDNA condensing activity, and electrostatic interactions involving NC's basic residues are responsible in large part for the conformation, size, and stability of the dsDNA-protein complex inside the viral core. We observe DNA re-solubilization and charge reversal in the presence of excess NC, consistent with the electrostatic nature of NC-induced DNA condensation. Previous studies of HIV-1 replication in the presence of the same cationic residue mutations in NC showed significant defects in both single- and multiple-round viral infectivity. Although NC participates in many stages of viral replication, our results are consistent with the hypothesis that cationic residue mutations inhibit genomic DNA condensation, resulting in increased premature capsid uncoating and contributing to viral replication defects.
Topics: HIV-1; Reverse Transcription; DNA, Viral; gag Gene Products, Human Immunodeficiency Virus; Humans; Cations; Virus Replication; Microscopy, Atomic Force; Virion; Mutation
PubMed: 38932164
DOI: 10.3390/v16060872 -
Viruses May 2024HIV-1 protease inhibitors are an essential component of antiretroviral therapy. However, drug resistance is a pervasive issue motivating a persistent search for novel...
HIV-1 protease inhibitors are an essential component of antiretroviral therapy. However, drug resistance is a pervasive issue motivating a persistent search for novel therapies. Recent reports found that when protease activates within the host cell's cytosol, it facilitates the pyroptotic killing of infected cells. This has led to speculation that promoting protease activation, rather than inhibiting it, could help to eradicate infected cells and potentially cure HIV-1 infection. Here, we used a nanoscale flow cytometry-based assay to characterize protease resistance mutations and polymorphisms. We quantified protease activity, viral concentration, and premature protease activation and confirmed previous findings that major resistance mutations generally destabilize the protease structure. Intriguingly, we found evidence that common polymorphisms in the hinge domain of protease can influence its susceptibility to premature activation. This suggests that viral heterogeneity could pose a considerable challenge for therapeutic strategies aimed at inducing premature protease activation in the future.
Topics: HIV Protease; HIV-1; Humans; Drug Resistance, Viral; Polymorphism, Genetic; HIV Infections; HIV Protease Inhibitors; Mutation
PubMed: 38932142
DOI: 10.3390/v16060849 -
Viruses May 2024A gene delivery system utilizing lentiviral vectors (LVs) requires high transduction efficiency for successful application in human gene therapy. Pseudotyping allows...
A gene delivery system utilizing lentiviral vectors (LVs) requires high transduction efficiency for successful application in human gene therapy. Pseudotyping allows viral tropism to be expanded, widening the usage of LVs. While vesicular stomatitis virus G (VSV-G) single-pseudotyped LVs are commonly used, dual-pseudotyping is less frequently employed because of its increased complexity. In this study, we examined the potential of phenotypically mixed heterologous dual-pseudotyped LVs with VSV-G and Sendai virus hemagglutinin-neuraminidase (SeV-HN) glycoproteins, termed V/HN-LV. Our findings demonstrated the significantly improved transduction efficiency of V/HN-LV in various cell lines of mice, cynomolgus monkeys, and humans compared with LV pseudotyped with VSV-G alone. Notably, V/HN-LV showed higher transduction efficiency in human cells, including hematopoietic stem cells. The efficient incorporation of wild-type SeV-HN into V/HN-LV depended on VSV-G. SeV-HN removed sialic acid from VSV-G, and the desialylation of VSV-G increased V/HN-LV infectivity. Furthermore, V/HN-LV acquired the ability to recognize sialic acid, particularly N-acetylneuraminic acid on the host cell, enhancing LV infectivity. Overall, VSV-G and SeV-HN synergistically improve LV transduction efficiency and broaden its tropism, indicating their potential use in gene delivery.
Topics: Animals; Humans; Genetic Vectors; Lentivirus; Sendai virus; Viral Envelope Proteins; Mice; Transduction, Genetic; HN Protein; Cell Line; Macaca fascicularis; Membrane Glycoproteins; Viral Tropism; HEK293 Cells; Gene Transfer Techniques; Genetic Therapy
PubMed: 38932120
DOI: 10.3390/v16060827 -
Medicina (Kaunas, Lithuania) May 2024: Adult T-cell leukemia/lymphoma (ATLL) is a highly aggressive T-cell lymphoproliferative disease associated with the human T-cell lymphotropic virus type I (HTLV-1).... (Observational Study)
Observational Study
: Adult T-cell leukemia/lymphoma (ATLL) is a highly aggressive T-cell lymphoproliferative disease associated with the human T-cell lymphotropic virus type I (HTLV-1). ATLL is a rare disease, found more frequently in HTLV-1-endemic areas, Romania being one of them. Despite treatment advances, the prognosis remains dismal. We aimed to describe the clinical, biological, and survival outcome features of Romanian patients with aggressive-type ATLL. We report the data of a prospective, observational, and unicentric study of all 20 patients diagnosed with lymphoma and acute types of ATLL at our center over the past 12 years. Data were collected from the patients' medical records. : Lymphoma-type ATLL (60%) was more common than acute-type ATLL (40%). Median age at diagnosis was 40.5 years, and most patients were female. Laboratory data revealed significant differences between acute and lymphoma-type ATLL, namely, higher leukocyte ( = 0.02) and lymphocyte counts ( = 0.02) and higher levels of corrected calcium ( = 0.001) in acute-type ATLL. All patients received chemotherapy, and only two underwent allogeneic stem cell transplantation. Only six patients obtained a complete or partial response to chemotherapy, mostly the lymphoma-type ones. The median survival for all patients was 6.37 months, with higher survival in the lymphoma-type ATLL (8.16 months) than in the acute-type (3.60 months). Normal calcium levels ( = 0.011), uric acid ( = 0.005), BUN score ( = 0.000), JCOG-PI moderate risk ( = 0.038), and obtaining complete or partial response ( = 0.037) were associated with higher survival. : Aggressive-type ATLL among Romanian patients presents distinct characteristics, including younger age at diagnosis, female predominance, and higher incidence of lymphoma-type ATLL compared to currently reported data. Survival remains very low, with all subtypes experiencing a median survival of less than one year.
Topics: Humans; Female; Leukemia-Lymphoma, Adult T-Cell; Male; Adult; Middle Aged; Romania; Prospective Studies; Human T-lymphotropic virus 1; HTLV-I Infections; Aged; Survival Analysis; Endemic Diseases; Prognosis
PubMed: 38929489
DOI: 10.3390/medicina60060872 -
International Journal of Molecular... Jun 2024The maturation of HIV-1 virions is a crucial process in viral replication. Although T-cells are a primary source of virus production, much of our understanding of virion...
The maturation of HIV-1 virions is a crucial process in viral replication. Although T-cells are a primary source of virus production, much of our understanding of virion maturation comes from studies using the HEK293T human embryonic kidney cell line. Notably, there is a lack of comparative analyses between T-cells and HEK293T cells in terms of virion maturation efficiency in existing literature. We previously developed an advanced virion visualization system based on the FRET principle, enabling the effective distinction between immature and mature virions via fluorescence microscopy. In this study, we utilized pseudotyped, single-round infectious viruses tagged with FRET labels (HIV-1 Gag-iFRET∆Env) derived from Jurkat (a human T-lymphocyte cell line) and HEK293T cells to evaluate their virion maturation rates. HEK293T-derived virions demonstrated a maturity rate of 81.79%, consistent with other studies and our previous findings. However, virions originating from Jurkat cells demonstrated a significantly reduced maturation rate of 68.67% ( < 0.0001). Correspondingly, viruses produced from Jurkat cells exhibited significantly reduced infectivity compared to those derived from HEK293T cells, with the relative infectivity measured at 65.3%. This finding is consistent with the observed relative maturation rate of viruses produced by Jurkat cells. These findings suggest that initiation of virion maturation directly correlates with viral infectivity. Our observation highlights the dynamic nature of virus-host interactions and their implications for virion production and infectivity.
Topics: Humans; HIV-1; HEK293 Cells; Virion; Jurkat Cells; Fluorescence Resonance Energy Transfer; Virus Replication; Virus Assembly; HIV Infections
PubMed: 38928103
DOI: 10.3390/ijms25126396 -
Genes Jun 2024Human endogenous retroviruses (HERVs) are DNA transposable elements that have integrated into the human genome via an ancestral germline infection. The potential... (Review)
Review
Human endogenous retroviruses (HERVs) are DNA transposable elements that have integrated into the human genome via an ancestral germline infection. The potential importance of HERVs is underscored by the fact that they comprise approximately 8% of the human genome. HERVs have been implicated in the pathogenesis of neurodegenerative diseases, a group of CNS diseases characterized by a progressive loss of structure and function of neurons, resulting in cell death and multiple physiological dysfunctions. Much evidence indicates that HERVs are initiators or drivers of neurodegenerative processes in multiple sclerosis and amyotrophic lateral sclerosis, and clinical trials have been designed to target HERVs. In recent years, the role of HERVs has been explored in other major neurodegenerative diseases, including frontotemporal dementia, Alzheimer's disease and Parkinson's disease, with some interesting discoveries. This review summarizes and evaluates the past and current research on HERVs in neurodegenerative diseases. It discusses the potential role of HERVs in disease manifestation and neurodegeneration. It critically reviews antiretroviral strategies used in the therapeutic intervention of neurodegenerative diseases.
Topics: Humans; Endogenous Retroviruses; Neurodegenerative Diseases; Amyotrophic Lateral Sclerosis; Animals
PubMed: 38927681
DOI: 10.3390/genes15060745 -
Genes May 2024Human T-cell leukemia virus type 1 (HTLV-1) is the causative agent of adult T-cell leukemia/lymphoma. The oncogene product Tax of HTLV-I is thought to play crucial roles...
Human T-cell leukemia virus type 1 (HTLV-1) is the causative agent of adult T-cell leukemia/lymphoma. The oncogene product Tax of HTLV-I is thought to play crucial roles in leukemogenesis by promoting proliferation of the virus-infected cells through activation of growth-promoting genes. These genes code for growth factors and their receptors, cytokines, cell adhesion molecules, growth signal transducers, transcription factors and cell cycle regulators. We show here that Tax activates the gene coding for coactivator-associated arginine methyltransferase 1 (CARM1), which epigenetically enhances gene expression through methylation of histones. Tax activated the gene and increased protein expression, not only in human T-cell lines but also in normal peripheral blood lymphocytes (PHA-PBLs). Tax increased R17-methylated histone H3 on the target gene , concomitant with increased expression of CARM1. Short hairpin RNA (shRNA)-mediated knockdown of CARM1 decreased Tax-mediated induction of and gene expression, reduced E2F activation and inhibited cell cycle progression. Tax acted via response elements in intron 1 of the gene, through the NF-κB pathway. These results suggest that Tax-mediated activation of the gene contributes to leukemogenic target-gene expression and cell cycle progression, identifying the first epigenetic target gene for Tax-mediated trans-activation in cell growth promotion.
Topics: Humans; Protein-Arginine N-Methyltransferases; Gene Products, tax; Human T-lymphotropic virus 1; Cyclin D2; Transcriptional Activation; Interleukin-2 Receptor alpha Subunit; NF-kappa B; Histones; Epigenesis, Genetic; Jurkat Cells
PubMed: 38927636
DOI: 10.3390/genes15060698 -
PloS One 2024The introduction of antiretroviral therapy (ART) has successfully changed the clinical course of people with HIV, leading to a significant decline in the incidence of...
The introduction of antiretroviral therapy (ART) has successfully changed the clinical course of people with HIV, leading to a significant decline in the incidence of HIV-related neurocognitive disorders. Integrase strand transferase inhibitors (INSTI) are recommended and preferred first-line ART for the treatment of HIV-1 infection in ART-naïve subjects. This type of therapy regimen is expected to have higher CNS penetration, which may bring more cognitive stability or even make significant cognitive improvement in people with HIV. The study aimed to follow up on neurocognitive performance in HIV subjects on two types of INSTI therapy regimens at two-time points, one year apart. The study sample consisted of 61 ART naïve male participants, of which 32 were prescribed raltegravir (RAL) and 29 dolutegravir (DTG). There was no significant difference between subsamples according to the main sociodemographic (age, education level) and clinical characteristics (duration of therapy, nadir CD4 cells level, CD4 cells count, CD8 cells, CD4/CD8 ratio). For neurocognitive assessment, six measures were used: general cognitive ability (MoCA test), verbal fluency (total sum score for phonemic and category fluency), verbal working memory (digit span forward), cognitive capacity (digit span backwards), sustained attention (Color Trail Test 1), and divided attention (Color Trail Test 2). In both therapy groups (RAL and DTG), there was no significant decrease in neurocognitive achievement on all used measures over a one-year follow-up in both therapy groups. A statistically significant interactive effect of time and type of therapy was found on the measure of divided attention-DTG group showed slight improvement, whereas RAL group showed slight decrease in performance. During the one-year follow-up of persons on INSTI-based regimen, no significant changes in cognitive achievement were recorded, which suggests that the existing therapy can have a potentially positive effect on the maintenance of neurocognitive achievement.
Topics: Humans; Male; HIV Infections; Adult; Follow-Up Studies; Cognition; Raltegravir Potassium; HIV Integrase Inhibitors; Middle Aged; Pyridones; Piperazines; Heterocyclic Compounds, 3-Ring; Oxazines; Neuropsychological Tests; HIV-1
PubMed: 38923982
DOI: 10.1371/journal.pone.0306278 -
PloS One 2024In 2019, WHO recommended dolutegravir (DTG) as a backbone for first- and second-line antiretroviral therapy (ART) regimens for people living with HIV (PLHIV). According...
BACKGROUND
In 2019, WHO recommended dolutegravir (DTG) as a backbone for first- and second-line antiretroviral therapy (ART) regimens for people living with HIV (PLHIV). According to the 2018 Uganda's HIV treatment guidelines, patients with viral non-suppression (≥1,000 copies/mL) should receive intensive adherence counseling (IAC) with repeat viral load (VL) within 6 months. This analysis focused on the prevalence and factors associated with viral suppression following IAC among PLHIV on DTG-based regimens (DBRs) with an initial episode of viral non-suppression (VNS) in Uganda.
METHODS
We conducted a retrospective analysis for PLHIV on DBRs with an initial episode of VNS (≥1,000 copies/mL) in Uganda during October 2019-September 2020 who had a follow up VL test result during September 2020-July 2021. Data were abstracted from the Central Public Health Laboratory (CPHL) database, including patient demographics and VL results. Viral non-suppression (VNS) was defined as a VL test result of ≥1,000 copies/mL. We characterized PLHIV on DBRs and used logistic regression models to determine factors associated with VL suppression after an initial episode of VNS.
RESULTS
A total of 564 PLHIV on DBRs with an initial episode of VNS were followed up and 43 were excluded due to missing data. Of the 521, 220 (42.2%) were children (<15 years) and 231 (44.3%) were female. Median age was 28 years (interquartile range [IQR]: 12-43 years), and median duration on DBRs was 12 months (IQR: 6-15 months). Overall, 80.8% (421/521) PLHIV had a suppressed viral load at first follow up testing (children = 74.5% [164/220]; adults = 85.4% [257/301]). Children with initial VL results ≥5,000 copies/mL were less likely to achieve viral suppression at follow up testing compared to those with <5,000 copies/mL (AOR: 0.38; 95% CI: 0.20-0.71; p = 0.002).
CONCLUSIONS
In a programmatic setting, most adults and children suppressed following an initial episode of VNS on DBRs. High rates of suppression after VNS suggest adherence challenges, rather than drug resistance. Continuation of DBRs should be considered before regimen switch.
Topics: Humans; Pyridones; Heterocyclic Compounds, 3-Ring; Female; Uganda; Male; HIV Infections; Adult; Oxazines; Viral Load; Piperazines; Retrospective Studies; HIV Integrase Inhibitors; Adolescent; Young Adult; Middle Aged; Anti-HIV Agents; Child; HIV-1
PubMed: 38923981
DOI: 10.1371/journal.pone.0305129 -
PloS One 2024Human Immunodeficiency Virus (HIV) is a significant threat to public health. HIV genotyping and antiretroviral resistance testing may have contributed to improved...
Human Immunodeficiency Virus (HIV) is a significant threat to public health. HIV genotyping and antiretroviral resistance testing may have contributed to improved non-treated management. Immune markers might assist HIV-1 diagnosis and drug-resistant variant identification. HIV-1 immunogenicity and molecular characteristics of antiretroviral drug resistance are evaluated in 56 treatment-naive HIV patients. DNA sequencing and retroviral resistance testing identified HIV-1 genotypes. 55.4% of patients were susceptible to protease inhibitors (PI), nucleoside reverse transcriptase inhibitors (NRTI), and non-nucleoside reverse transcriptase inhibitors (NNRTI) antiretroviral drugs, whereas 44.6% had drug-resistance mutations against at least one antiretroviral drug. 3.6% of cases had PI-resistant mutations, while 30.4% had NRTI-resistant mutations, and 30.4% had NNRTI-resistant mutations. In patients who are susceptible to PI, the mean value of human plasma sCD80 is 2.11 ± 0.65 ng/mL; in patients with mutations, it is 3.93 ± 2.91 ng/mL. Individuals who are susceptible to PI have plasma sCD27 levels of 78.7 ± 63.2 U/mL, whereas individuals who are mutant have levels of 56.5 ± 32.1 U/mL. IP-10's mean value was 363 ± 109.2 pg/mL for the susceptible patients and 429 ± 20.7 pg/mL for the mutated patients. In susceptible patients, the plasma sCD4 level is 0.163 ± 0.229 ng/mL; in mutant patients, it is 0.084 ± 0.012 ng/mL. The data showed a relative relation between immunological parameters such as sCD80, sCD27, sCD4, and IP-10 and mutation for drug resistance.
Topics: Humans; HIV-1; Saudi Arabia; Male; Drug Resistance, Viral; Mutation; HIV Infections; Female; Adult; Middle Aged; Anti-HIV Agents; Genotype; Young Adult
PubMed: 38923958
DOI: 10.1371/journal.pone.0304408