Treatment outcomes amongst older people with HIV infection receiving antiretroviral therapy.

OBJECTIVES: There is conflicting data regarding the response of older people with HIV (PWH) to antiretroviral therapy (ART). The objective of this study was to evaluate the long-term immunological and virological responses, changes in regimen, and adverse drug reactions (ADRs) in older participants (50+ years) compared with younger (18-34 years) and middle-aged (35-49 years) PWH. METHODS: A retrospective review of medical records was conducted on 1622 participants who received ART in Yunnan Province, China, from 2010 to 2019. The study compared CD4+ T-cell counts, CD4+/CD8+ ratio, and relative numbers between different groups using the Kruskal-Wallis test. Cox proportional hazards regression models were used to identify variables associated with the occurrence of immune reconstitution insufficiency. The rates of immune reconstitution, incidence of ADRs, and rates of treatment change were analyzed using the chi-squared test or Fisher's exact test. RESULTS: Over 95% achieved viral load 200 copies/ml or less, with no age-related difference. However, older participants exhibited significantly lower CD4+ T-cell counts and CD4+/CD8+ recovery post-ART (P < 0.001), with only 32.21% achieving immune reconstitution (compared with young: 52.16%, middle-aged: 39.29%, P < 0.001) at the end of follow-up. Middle-aged and elderly participants changed ART regimens more because of ADRs, especially bone marrow suppression and renal dysfunction. CONCLUSION: Although the virological response was consistent across age groups, older individuals showed poorer immune responses and higher susceptibility to side effects. This underscores the need for tailored interventions and comprehensive management for older patients with HIV.

A Review on The Pathogenesis of Cardiovascular Disease of Flaviviridea Viruses Infection.

Members of the Flaviviridae family, encompassing the Flavivirus and Hepacivirus genera, are implicated in a spectrum of severe human pathologies. These diseases span a diverse spectrum, including hepatitis, vascular shock syndrome, encephalitis, acute flaccid paralysis, and adverse fetal outcomes, such as congenital heart defects and increased mortality rates. Notably, infections by Flaviviridae viruses have been associated with substantial cardiovascular compromise, yet the exploration into the attendant cardiovascular sequelae and underlying mechanisms remains relatively underexplored. This review aims to explore the epidemiology of Flaviviridae virus infections and synthesize their cardiovascular morbidities. Leveraging current research trajectories and our investigative contributions, we aspire to construct a cogent theoretical framework elucidating the pathogenesis of Flaviviridae-induced cardiovascular injury and illuminate prospective therapeutic avenues.

gp120-derived amyloidogenic peptides form amyloid fibrils that increase HIV-1 infectivity.

Apart from mediating viral entry, the function of the free HIV-1 envelope protein (gp120) has yet to be elucidated. Our group previously showed that EP2 derived from one ß-strand in gp120 can form amyloid fibrils that increase HIV-1 infectivity. Importantly, gp120 contains ~30 ß-strands. We examined whether gp120 might serve as a precursor protein for the proteolytic release of amyloidogenic fragments that form amyloid fibrils, thereby promoting viral infection. Peptide array scanning, enzyme degradation assays, and viral infection experiments in vitro confirmed that many ß-stranded peptides derived from gp120 can indeed form amyloid fibrils that increase HIV-1 infectivity. These gp120-derived amyloidogenic peptides, or GAPs, which were confirmed to form amyloid fibrils, were termed gp120-derived enhancers of viral infection (GEVIs). GEVIs specifically capture HIV-1 virions and promote their attachment to target cells, thereby increasing HIV-1 infectivity. Different GAPs can cross-interact to form heterogeneous fibrils that retain the ability to increase HIV-1 infectivity. GEVIs even suppressed the antiviral activity of a panel of antiretroviral agents. Notably, endogenous GAPs and GEVIs were found in the lymphatic fluid, lymph nodes, and cerebrospinal fluid (CSF) of AIDS patients in vivo. Overall, gp120-derived amyloid fibrils might play a crucial role in the process of HIV-1 infectivity and thus represent novel targets for anti-HIV therapeutics.

Nonnegligible Contribution of Nonlymphoid Tissue to Viral Reservoir During the Short-Term Early cART in SIVmac239-Infected Chinese Rhesus Macaques.

HIV/AIDS cannot be cured because of the persistence of the viral reservoir. Because of the complexity of the cellular composition and structure of the human organs, HIV reservoirs of anatomical site are also complex. Recently, although a variety of molecules have been reported to be involved in the establishment and maintenance of the viral reservoirs, or as marker of latent cells, the research mainly focuses on blood and lymph nodes. Now, the characteristics of the viral reservoir in tissue are not yet fully understood. In this study, various tissues were collected from SIVmac239-infected monkeys, and the level of total SIV DNA, SIV 2-LTR DNA, and cell-associated virus RNA in them were compared with character of the anatomical viral reservoir under early treatment. The results showed that short-term combination antiretroviral therapy (cART) starting from 3 days after infection could significantly inhibit viremia and reduce the size of the anatomical viral reservoir, but it could not eradicate de novo infections and ongoing replication of virus. Moreover, the effects of early cART on the level of total SIV DNA, SIV 2-LTR DNA, and cell-associated virus RNA in different tissues were different, which changed the size distribution of viral reservoir in anatomical site. Finally, the contribution of nonlymphoid tissues, especially liver and lung, to the viral reservoir increased after treatment, while the contribution of intestinal lymphoid to the viral reservoir significantly reduced. These results suggested that early treatment effectively decreased the size of viral reservoir, and that the effects of cART on the tissue viral reservoir varied greatly by tissue type. The results implied that persistent existence of virus in nonlymphoid tissues after short-term treatment suggested that the role of nonlymphoid tissues cannot be ignored in development strategies for AIDS therapy.

Mast cell degranulation-triggered by SARS-CoV-2 induces tracheal-bronchial epithelial inflammation and injury.

SARS-CoV-2 infection-induced hyper-inflammation is a key pathogenic factor of COVID-19. Our research, along with others', has demonstrated that mast cells (MCs) play a vital role in the initiation of hyper-inflammation caused by SARS-CoV-2. In previous study, we observed that SARS-CoV-2 infection induced the accumulation of MCs in the peri-bronchus and bronchioalveolar-duct junction in humanized mice. Additionally, we found that MC degranulation triggered by the spike protein resulted in inflammation in alveolar epithelial cells and capillary endothelial cells, leading to subsequent lung injury. The trachea and bronchus are the routes for SARS-CoV-2 transmission after virus inhalation, and inflammation in these regions could promote viral spread. MCs are widely distributed throughout the respiratory tract. Thus, in this study, we investigated the role of MCs and their degranulation in the development of inflammation in tracheal-bronchial epithelium. Histological analyses showed the accumulation and degranulation of MCs in the peri-trachea of humanized mice infected with SARS-CoV-2. MC degranulation caused lesions in trachea, and the formation of papillary hyperplasia was observed. Through transcriptome analysis in bronchial epithelial cells, we found that MC degranulation significantly altered multiple cellular signaling, particularly, leading to upregulated immune responses and inflammation. The administration of ebastine or loratadine effectively suppressed the induction of inflammatory factors in bronchial epithelial cells and alleviated tracheal injury in mice. Taken together, our findings confirm the essential role of MC degranulation in SARS-CoV-2-induced hyper-inflammation and the subsequent tissue lesions. Furthermore, our results support the use of ebastine or loratadine to inhibit SARS-CoV-2-triggered degranulation, thereby preventing tissue damage caused by hyper-inflammation.

Identification of novel mammalian viruses in tree shrews ( Tupaia belangeri chinensis).

The Chinese tree shrew ( Tupaia belangeri chinensis), a member of the mammalian order Scandentia, exhibits considerable similarities with primates, including humans, in aspects of its nervous, immune, and metabolic systems. These similarities have established the tree shrew as a promising experimental model for biomedical research on cancer, infectious diseases, metabolic disorders, and mental health conditions. Herein, we used meta-transcriptomic sequencing to analyze plasma, as well as oral and anal swab samples, from 105 healthy asymptomatic tree shrews to identify the presence of potential zoonotic viruses. In total, eight mammalian viruses with complete genomes were identified, belonging to six viral families, including Flaviviridae, Hepeviridae, Parvovirinae, Picornaviridae, Sedoreoviridae, and Spinareoviridae. Notably, the presence of rotavirus was recorded in tree shrews for the first time. Three viruses - hepacivirus 1, parvovirus, and picornavirus - exhibited low genetic similarity (<70%) with previously reported viruses at the whole-genome scale, indicating novelty. Conversely, three other viruses - hepacivirus 2, hepatovirus A and hepevirus - exhibited high similarity (>94%) to known viral strains. Phylogenetic analyses also revealed that the rotavirus and mammalian orthoreovirus identified in this study may be novel reassortants. These findings provide insights into the diverse viral spectrum present in captive Chinese tree shrews, highlighting the necessity for further research into their potential for cross-species transmission.

Transcriptional regulation of SARS-CoV-2 receptor ACE2 by SP1.

Angiotensin-converting enzyme 2 (ACE2) is a major cell entry receptor for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The induction of ACE2 expression may serve as a strategy by SARS-CoV-2 to facilitate its propagation. However, the regulatory mechanisms of ACE2 expression after viral infection remain largely unknown. Using 45 different luciferase reporters, the transcription factors SP1 and HNF4α were found to positively and negatively regulate ACE2 expression, respectively, at the transcriptional level in human lung epithelial cells (HPAEpiCs). SARS-CoV-2 infection increased the transcriptional activity of SP1 while inhibiting that of HNF4α. The PI3K/AKT signaling pathway, activated by SARS-CoV-2 infection, served as a crucial regulatory node, inducing ACE2 expression by enhancing SP1 phosphorylation-a marker of its activity-and reducing the nuclear localization of HNF4α. However, colchicine treatment inhibited the PI3K/AKT signaling pathway, thereby suppressing ACE2 expression. In Syrian hamsters (Mesocricetus auratus) infected with SARS-CoV-2, inhibition of SP1 by either mithramycin A or colchicine resulted in reduced viral replication and tissue injury. In summary, our study uncovers a novel function of SP1 in the regulation of ACE2 expression and identifies SP1 as a potential target to reduce SARS-CoV-2 infection.

Semisynthesis of homogeneous spike RBD glycoforms from SARS-CoV-2 for profiling the correlations between glycan composition and function.

Vaccines have been the primary remedy in the global fight against coronavirus disease 2019 (COVID-19). The receptor-binding domain (RBD) of the spike protein, a critical viral immunogen, is affected by the heterogeneity of its glycan structures and relatively low immunogenicity. Here, we describe a scalable synthetic platform that enables the precise synthesis of homogeneously glycosylated RBD, facilitating the elucidation of carbohydrate structure-function relationships. Five homogeneously glycosylated RBDs bearing biantennary glycans were prepared, three of which were conjugated to T-helper epitope (Tpep) from tetanus toxoid to improve their weak immune response. Relative to natural HEK293-derived RBD, synthetic RBDs with biantennary N-glycan elicited a higher level of neutralising antibodies against SARS-CoV-2 in mice. Furthermore, RBDs containing Tpep elicited significant immune responses in transgenic mice expressing human angiotensin-converting enzyme 2. Our collective data suggest that trimming the N-glycans and Tpep conjugation of RBD could potentially serve as an effective strategy for developing subunit vaccines providing efficient protection.

Increased cAMP-PKA signaling pathway activation is involved in up-regulation of CTLA-4 expression in CD4+ T cells in acute SIVmac239-infected Chinese rhesus macaques.

Human immunodeficiency virus-1 (HIV-1) infection can cause chronic activation, exhaustion, and anergy of the immune system. Cytotoxic T lymphocyte-associated antigen-4 (CTLA-4) is an immune checkpoint molecule, which plays an important role in immune homeostasis and disease. CTLA-4 expression is elevated in HIV-1-infected patients and is associated with disease progression. However, the mechanism controlling expression of CTLA-4 in HIV-1 infection is poorly characterized. In this study, we used a SIV-infected Chinese rhesus macaque (ChRM) model to explore CTLA-4 expression in SIV infection. Results showed that SIV infection significantly increased CTLA-4 expression in all T cell subsets, especially central memory T cells. CTLA-4+CD4+ T cell frequency was significantly associated with disease progression markers. Activation of the cyclic adenosine monophosphate (cAMP)-protein kinase A (PKA) signaling pathway regulated CTLA-4 expression in CD4+T cells, as confirmed by stimulation with dibutyryl cyclic adenosine monophosphate, forskolin, and 3-isobutyl-1-methylxanthine, and inhibition with H-89 ex vivo. Simultaneously, cAMP concentration in PBMCs and PKA activity in both PBMCs and CD4+ T cells were increased in acute SIV-infected ChRMs, accompanied by an increase in adenylate cyclase 6 expression and a decrease in cAMP-phosphodiesterase 3A (PDE3A), PDE4B, and PDE5A expression in PBMCs. In addition, selective inhibition of PDE4B and PDE5A activity enhanced CTLA-4 expression in CD4+ T cells. These results suggest that SIV infection alters cAMP metabolism and increases cAMP-PKA signaling pathway activation, which up-regulates the expression of CTLA-4 in acute SIVmac239-infected ChRMs. Thus, regulation of the cAMP-PKA signaling pathway may be a potential strategy for the restoration of T cell function and therapy for AIDS.

Novel Triazolopyridine-Based BRD4 Inhibitors as Potent HIV-1 Latency Reversing Agents.

Bromodomain-containing protein 4 (BRD4) inhibitors have been proven to be a promising option for anti-HIV-1 latency therapeutics. We herein describe the design, synthesis, and anti-HIV-1 latency bioevaluation of triazolopyridine derivatives as BRD4 inhibitors. Among them, compound 13d displayed favorable HIV-1 reactivation and prominent safety profile without triggering abnormal immune activation. It exerted strong synergism when combined with the PKC activator prostratin and has the same BRD4-targeting latency mechanism as observed with JQ1, by stimulating Tat-dependent HIV-1 elongation. Besides, it neither affected the antiviral efficacies of antiviral drugs nor caused secondary infections to uninfected cells and the latency reversing potency of 13d, in turn, was not affected by different classes of antiviral drugs.

SARS-CoV-2 NSP12 utilizes various host splicing factors for replication and splicing regulation.

The RNA-dependent RNA polymerase (RdRp) is a crucial element in the replication and transcription of RNA viruses. Although the RdRps of lethal human coronaviruses severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), SARS-CoV, and Middle East respiratory syndrome coronavirus (MERS-CoV) have been extensively studied, the molecular mechanism of the catalytic subunit NSP12, which is involved in pathogenesis, remains unclear. In this study, the biochemical and cell biological results demonstrate the interactions between SARS-CoV-2 NSP12 and seven host proteins, including three splicing factors (SLU7, PPIL3, and AKAP8). The entry efficacy of SARS-CoV-2 considerably decreased when SLU7 or PPIL3 was knocked out, indicating that abnormal splicing of the host genome was responsible for this occurrence. Furthermore, the polymerase activity and stability of SARS-CoV-2 RdRp were affected by the three splicing factors to varying degrees. In addition, NSP12 and its homologues from SARS-CoV and MERS-CoV suppressed the alternative splicing of cellular genes, which were influenced by the three splicing factors. Overall, our research illustrates that SARS-CoV-2 NSP12 can engage with various splicing factors, thereby impacting virus entry, replication, and gene splicing. This not only improves our understanding of how viruses cause diseases but also lays the foundation for the development of antiviral therapies.

The hydroxamic acid derivative YPX-C-05 alleviates hypertension and vascular dysfunction through the PI3K/Akt/eNOS pathway.

BACKGROUND: Hypertension is a prevalent cardiovascular disease characterized by elevated blood pressure and increased vascular resistance. HDAC inhibitors have emerged as potential therapeutic agents due to their ability to modulate gene expression and cellular processes. YPX-C-05, a novel hydroxamic acid-based HDAC inhibitor, shows promise in its vasodilatory effects and potential targets for hypertension treatment. In this study, we aimed to elucidate the mechanisms underlying YPX-C-05's vasodilatory effects and explore its therapeutic potential in hypertension. METHODS: To determine the ex vivo vasodilatory effects of YPX-C-05, isolated aortic rings precontracted with phenylephrine were used. We assessed YPX-C-05's inhibitory effects on HDACs and its impact on histone H4 deacetylation levels in endothelial cells. Network pharmacology analysis was employed to predict putative targets of YPX-C-05 for hypertension treatment. To investigate the involvement of the PI3K/Akt/eNOS pathway, we employed enzyme-linked immunosorbent assay and to assess the levels of NO, ET-1, BH2, and BH4 in human umbilical vein endothelial cells. And we also analyzed the mRNA expression of eNOS and ET-1. Furthermore, Western blotting was conducted to quantify the phosphorylated and total Akt and eNOS levels in human umbilical vein endothelial cell lysates following treatment with YPX-C-05. In order to elucidate the vasodilatory mechanism of YPX-C-05, we employed pharmacological inhibitors for evaluation purposes. Furthermore, we evaluated the chronic antihypertensive effects of YPX-C-05 on N-omega-nitro-L-arginine-induced hypertensive mice in an in vivo model. Vascular remodeling was assessed through histological analysis. RESULTS: Our findings demonstrated that YPX-C-05 exerts significant vasodilatory effects in isolated aortic rings precontracted with phenylephrine. Furthermore, YPX-C-05 exhibited inhibitory effects on HDACs and increased histone H4 acetylation in endothelial cells. Network pharmacology analysis predicted YPX-C-05 might activate endothelial eNOS via PI3K/Akt signaling pathway. Inhibition of the PI3K/Akt/eNOS pathway attenuated the vasodilatory effects of YPX-C-05, as evidenced by reduced levels of phosphorylated Akt and eNOS in human umbilical vein endothelial cell lysates. The chronic administration of YPX-C-05 in N-omega-nitro-L-arginine-induced hypertensive mice resulted in significant antihypertensive effects. Histological analysis demonstrated a reduction in vascular remodeling, further supporting the therapeutic potential of YPX-C-05 in hypertension. CONCLUSION: This study demonstrates for the first time that the novel hydroxamic acid-based HDAC inhibitor YPX-C-05 produces significant antihypertensive and vasodilatory effects through the PI3K/Akt/eNOS pathway. Our findings support the developing prospect of YPX-C-05 as a novel antihypertensive drug.

Severe fever with thrombocytopenia syndrome virus induces platelet activation and apoptosis via a reactive oxygen species-dependent pathway.

Severe fever with thrombocytopenia syndrome (SFTS) is an emerging tick-borne infectious disease caused by the SFTS virus (SFTSV) and with a high fatality rate. Thrombocytopenia is a major clinical manifestation observed in SFTS patients, but the underlying mechanism remains largely unclear. Here, we explored the effects of SFTSV infection on platelet function in vivo in severely infected SFTSV IFNar-/- mice and on mouse and human platelet function in vitro. Results showed that SFTSV-induced platelet clearance acceleration may be the main reason for thrombocytopenia. SFTSV-potentiated platelet activation and apoptosis were also observed in infected mice. Further investigation showed that SFTSV infection induced platelet reactive oxygen species (ROS) production and mitochondrial dysfunction. In vitro experiments revealed that administration of SFTSV or SFTSV glycoprotein (Gn) increased activation, apoptosis, ROS production, and mitochondrial dysfunction in separated mouse platelets, which could be effectively ameliorated by the application of antioxidants (NAC (N-acetyl-l-cysteine), SKQ1 (10-(6'-plastoquinonyl) decyltriphenylphosphonium) and resveratrol). In vivo experiments showed that the antioxidants partially rescued SFTSV infection-induced thrombocytopenia by improving excessive ROS production and mitochondrial dysfunction and down-regulating platelet apoptosis and activation. Furthermore, while SFTSV and Gn directly potentiated human platelet activation, it was completely abolished by antioxidants. This study revealed that SFTSV and Gn can directly trigger platelet activation and apoptosis in an ROS-MAPK-dependent manner, which may contribute to thrombocytopenia and hemorrhage during infection, but can be abolished by antioxidants.

Comparative genomics reveals the hybrid origin of a macaque group.

Although species can arise through hybridization, compelling evidence for hybrid speciation has been reported only rarely in animals. Here, we present phylogenomic analyses on genomes from 12 macaque species and show that the fascicularis group originated from an ancient hybridization between the sinica and silenus groups ~3.45 to 3.56 million years ago. The X chromosomes and low-recombination regions exhibited equal contributions from each parental lineage, suggesting that they were less affected by subsequent backcrossing and hence could have played an important role in maintaining hybrid integrity. We identified many reproduction-associated genes that could have contributed to the development of the mixed sexual phenotypes characteristic of the fascicularis group. The phylogeny within the silenus group was also resolved, and functional experimentation confirmed that all extant Western silenus species are susceptible to HIV-1 infection. Our study provides novel insights into macaque evolution and reveals a hybrid speciation event that has occurred only very rarely in primates.

Temporal trends and projections of gynecological cancers in China, 2007-2030.

BACKGROUND: Gynecological cancer will become a more important public health problem in future years but limited evidence on gynecological cancer burden in China. METHODS: We extracted age-specific rate of cancer cases and deaths during 2007-2016 from the Chinese Cancer Registry Annual Report, and estimated age-specific population size using the data released by National Bureau of Statistics of China. Cancer burden were calculated by multiplying the rates with the population size. Temporal trends of the cancer cases, incidence, deaths, and mortality during 2007-2016 were calculated by JoinPoint Regression Program, and from 2017 to 2030 were projected by grey prediction model GM (1,1). RESULTS: In China, total gynecological cancer cases increased from 177,839 to 241,800, with the average annual percentage change of 3.5% (95% CI: 2.7-4.3%) during 2007-2016. Cervical, uterine, ovarian, vulva, and other gynecological cancer cases increased by 4.1% (95% CI: 3.3-4.9%), 3.3% (95% CI: 2.6-4.1%), 2.4% (95% CI: 1.4-3.5%), 4.4% (95% CI: 2.5-6.4%), and 3.6% (95% CI: 1.4-5.9%) respectively. From 2017 to 2030, projected gynecological cancer cases are changing from 246,581 to 408,314. Cervical, vulva and vaginal cancers showed evident upward trend, while uterine and ovarian cancer cases are slightly increasing. The increases for age-standardized incidence rates were similar with that of cancer cases. Temporal trends of cancer deaths and mortality were similar with that of cancer cases and incidence during 2007-2030, except that uterine cancer deaths and mortality were declined. CONCLUSIONS: With the aging of population and other increased risk factors, the burden of gynecological cancers in China is likely to be grew rapidly in the future, comprehensive gynecological cancer control should be concerned.

Immune resilience despite inflammatory stress promotes longevity and favorable health outcomes including resistance to infection.

Some people remain healthier throughout life than others but the underlying reasons are poorly understood. Here we hypothesize this advantage is attributable in part to optimal immune resilience (IR), defined as the capacity to preserve and/or rapidly restore immune functions that promote disease resistance (immunocompetence) and control inflammation in infectious diseases as well as other causes of inflammatory stress. We gauge IR levels with two distinct peripheral blood metrics that quantify the balance between (i) CD8+ and CD4+ T-cell levels and (ii) gene expression signatures tracking longevity-associated immunocompetence and mortality-associated inflammation. Profiles of IR metrics in ~48,500 individuals collectively indicate that some persons resist degradation of IR both during aging and when challenged with varied inflammatory stressors. With this resistance, preservation of optimal IR tracked (i) a lower risk of HIV acquisition, AIDS development, symptomatic influenza infection, and recurrent skin cancer; (ii) survival during COVID-19 and sepsis; and (iii) longevity. IR degradation is potentially reversible by decreasing inflammatory stress. Overall, we show that optimal IR is a trait observed across the age spectrum, more common in females, and aligned with a specific immunocompetence-inflammation balance linked to favorable immunity-dependent health outcomes. IR metrics and mechanisms have utility both as biomarkers for measuring immune health and for improving health outcomes.

TRIM5α recruits HDAC1 to p50 and Sp1 and promotes H3K9 deacetylation at the HIV-1 LTR.

Tripartite motif-containing protein 5α (TRIM5α) is generally known to block the postentry events of HIV-1. Here, we report an uncharacterized role for TRIM5α in the maintenance of viral latency. Knockdown of TRIM5α potentiates the transcription of HIV-1 in multiple latency models, which is reversed by shRNA-resistant TRIM5α. TRIM5α suppresses TNFα-activated HIV-1 LTR-driven as well as NF-κB- and Sp1-driven gene expression, with the RING and B-box 2 domains being the essential determinants. Mechanistically, TRIM5α binds to and enhances the recruitment of histone deacetylase 1 (HDAC1) to NF-κB p50 and Sp1. ChIP‒qPCR analyses further reveal that the association of TRIM5α with HIV-1 LTR induces HDAC1 recruitment and local H3K9 deacetylation. Conserved suppression effects of TRIM5α orthologs from multiple species on both HIV-1 and endo-retroelement HERV-K LTR activities have also been demonstrated. These findings provide new insights into the molecular mechanisms by which proviral latency is initially established and activatable proviruses are resilenced by histone deacetylase recruitment.

Genomic Evidence for the Nonpathogenic State in HIV-1-Infected Northern Pig-Tailed Macaques.

HIV-1 is a highly host-specific retrovirus that infects humans but not most nonhuman primates. Thus, the lack of a suitable primate model that can be directly infected with HIV-1 hinders HIV-1/AIDS research. In the previous study, we have found that the northern pig-tailed macaques (NPMs) are susceptible to HIV-1 infection but show a nonpathogenic state. In this study, to understand this macaque-HIV-1 interaction, we assembled a de novo genome and longitudinal transcriptome for this species during the course of HIV-1 infection. Using comparative genomic analysis, a positively selected gene, Toll-like receptor 8, was identified with a weak ability to induce an inflammatory response in this macaque. In addition, an interferon-stimulated gene, interferon alpha inducible protein 27, was upregulated in acute HIV-1 infection and acquired an enhanced ability to inhibit HIV-1 replication compared with its human ortholog. These findings coincide with the observation of persistently downregulated immune activation and low viral replication and can partially explain the AIDS-free state in this macaque following HIV-1 infection. This study identified a number of unexplored host genes that may hamper HIV-1 replication and pathogenicity in NPMs and provided new insights into the host defense mechanisms in cross-species infection of HIV-1. This work will facilitate the adoption of NPM as a feasible animal model for HIV-1/AIDS research.

Preventive and therapeutic benefits of nelfinavir in rhesus macaques and human beings infected with SARS-CoV-2.

Effective drugs with broad spectrum safety profile to all people are highly expected to combat COVID-19 caused by SARS-CoV-2. Here we report that nelfinavir, an FDA approved drug for the treatment of HIV infection, is effective against SARS-CoV-2 and COVID-19. Preincubation of nelfinavir could inhibit the activity of the main protease of the SARS-CoV-2 (IC50 = 8.26 µM), while its antiviral activity in Vero E6 cells against a clinical isolate of SARS-CoV-2 was determined to be 2.93 µM (EC50). In comparison with vehicle-treated animals, rhesus macaque prophylactically treated with nelfinavir had significantly lower temperature and significantly reduced virus loads in the nasal and anal swabs of the animals. At necropsy, nelfinavir-treated animals had a significant reduction of the viral replication in the lungs by nearly three orders of magnitude. A prospective clinic study with 37 enrolled treatment-naive patients at Shanghai Public Health Clinical Center, which were randomized (1:1) to nelfinavir and control groups, showed that the nelfinavir treatment could shorten the duration of viral shedding by 5.5 days (9.0 vs. 14.5 days, P = 0.055) and the duration of fever time by 3.8 days (2.8 vs. 6.6 days, P = 0.014) in mild/moderate COVID-19 patients. The antiviral efficiency and clinical benefits in rhesus macaque model and in COVID-19 patients, together with its well-established good safety profile in almost all ages and during pregnancy, indicated that nelfinavir is a highly promising medication with the potential of preventative effect for the treatment of COVID-19.