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1.
Cell ; 171(3): 655-667.e17, 2017 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-29053971

RESUMO

The gut microbiota contributes to the development of normal immunity but, when dysregulated, can promote autoimmunity through various non-antigen-specific effects on pathogenic and regulatory lymphocytes. Here, we show that an integrase expressed by several species of the gut microbial genus Bacteroides encodes a low-avidity mimotope of the pancreatic ß cell autoantigen islet-specific glucose-6-phosphatase-catalytic-subunit-related protein (IGRP206-214). Studies in germ-free mice monocolonized with integrase-competent, integrase-deficient, and integrase-transgenic Bacteroides demonstrate that the microbial epitope promotes the recruitment of diabetogenic CD8+ T cells to the gut. There, these effectors suppress colitis by targeting microbial antigen-loaded, antigen-presenting cells in an integrin ß7-, perforin-, and major histocompatibility complex class I-dependent manner. Like their murine counterparts, human peripheral blood T cells also recognize Bacteroides integrase. These data suggest that gut microbial antigen-specific cytotoxic T cells may have therapeutic value in inflammatory bowel disease and unearth molecular mimicry as a novel mechanism by which the gut microbiota can regulate normal immune homeostasis. PAPERCLIP.


Assuntos
Autoantígenos/imunologia , Bacteroides/imunologia , Colite/imunologia , Microbioma Gastrointestinal , Glucose-6-Fosfatase/imunologia , Adulto , Animais , Bacteroides/classificação , Bacteroides/enzimologia , Colite/microbiologia , Feminino , Glucose-6-Fosfatase/genética , Humanos , Tecido Linfoide/imunologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos NOD , Pessoa de Meia-Idade , Mimetismo Molecular , Linfócitos T/imunologia
2.
Mol Cell ; 73(4): 727-737.e3, 2019 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-30709710

RESUMO

CRISPR-Cas immunity requires integration of short, foreign DNA fragments into the host genome at the CRISPR locus, a site consisting of alternating repeat sequences and foreign-derived spacers. In most CRISPR systems, the proteins Cas1 and Cas2 form the integration complex and are both essential for DNA acquisition. Most type V-C and V-D systems lack the cas2 gene and have unusually short CRISPR repeats and spacers. Here, we show that a mini-integrase comprising the type V-C Cas1 protein alone catalyzes DNA integration with a preference for short (17- to 19-base-pair) DNA fragments. The mini-integrase has weak specificity for the CRISPR array. We present evidence that the Cas1 proteins form a tetramer for integration. Our findings support a model of a minimal integrase with an internal ruler mechanism that favors shorter repeats and spacers. This minimal integrase may represent the function of the ancestral Cas1 prior to Cas2 adoption.


Assuntos
Proteínas Associadas a CRISPR/genética , Sistemas CRISPR-Cas , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , DNA Bacteriano/genética , Endodesoxirribonucleases/genética , Endonucleases/genética , Proteínas de Escherichia coli/genética , Escherichia coli/genética , Edição de Genes/métodos , Integrases/genética , Pareamento de Bases , Proteínas Associadas a CRISPR/metabolismo , DNA Bacteriano/metabolismo , Endodesoxirribonucleases/metabolismo , Endonucleases/metabolismo , Escherichia coli/enzimologia , Proteínas de Escherichia coli/metabolismo , Regulação Bacteriana da Expressão Gênica , Integrases/metabolismo , Motivos de Nucleotídeos , Especificidade por Substrato
3.
J Biol Chem ; 300(6): 107374, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38762180

RESUMO

The pre-integration steps of the HIV-1 viral cycle are some of the most valuable targets of recent therapeutic innovations. HIV-1 integrase (IN) displays multiple functions, thanks to its considerable conformational flexibility. Recently, such flexible proteins have been characterized by their ability to form biomolecular condensates as a result of Liquid-Liquid-Phase-Separation (LLPS), allowing them to evolve in a restricted microenvironment within cells called membrane-less organelles (MLO). The LLPS context constitutes a more physiological approach to study the integration of molecular mechanisms performed by intasomes (complexes containing viral DNA, IN, and its cellular cofactor LEDGF/p75). We investigated here if such complexes can form LLPS in vitro and if IN enzymatic activities were affected by this LLPS environment. We observed that the LLPS formed by IN-LEDGF/p75 functional complexes modulate the in vitro IN activities. While the 3'-processing of viral DNA ends was drastically reduced inside LLPS, viral DNA strand transfer was strongly enhanced. These two catalytic IN activities appear thus tightly regulated by the environment encountered by intasomes.


Assuntos
Integrase de HIV , HIV-1 , Integração Viral , Integrase de HIV/metabolismo , Integrase de HIV/química , Integrase de HIV/genética , HIV-1/metabolismo , HIV-1/fisiologia , Humanos , DNA Viral/metabolismo , DNA Viral/genética , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/química
4.
Mol Microbiol ; 121(6): 1200-1216, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38705589

RESUMO

Through their involvement in the integration and excision of a large number of mobile genetic elements, such as phages and integrative and conjugative elements (ICEs), site-specific recombination systems based on heterobivalent tyrosine recombinases play a major role in genome dynamics and evolution. However, despite hundreds of these systems having been identified in genome databases, very few have been described in detail, with none from phages that infect Bacillota (formerly Firmicutes). In this study, we reanalyzed the recombination module of Lactobacillus delbrueckii subsp. bulgaricus phage mv4, previously considered atypical compared with classical systems. Our results reveal that mv4 integrase is a 369 aa protein with all the structural hallmarks of recombinases from the Tn916 family and that it cooperatively interacts with its recombination sites. Using randomized DNA libraries, NGS sequencing, and other molecular approaches, we show that the 21-bp core-attP and attB sites have structural similarities to classical systems only if considering the nucleotide degeneracy, with two 7-bp inverted regions corresponding to mv4Int core-binding sites surrounding a 7-bp strand-exchange region. We also examined the different compositional constraints in the core-binding regions, which define the sequence space of permissible recombination sites.


Assuntos
Sítios de Ligação Microbiológicos , Bacteriófagos , Integrases , Recombinação Genética , Bacteriófagos/genética , Integrases/metabolismo , Integrases/genética , Sítios de Ligação Microbiológicos/genética , Lactobacillus delbrueckii/virologia , Lactobacillus delbrueckii/genética , Recombinases/metabolismo , Recombinases/genética , Sítios de Ligação
5.
Development ; 149(16)2022 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-35980363

RESUMO

Visualizing cell shapes and interactions of differentiating cells is instrumental for understanding organ development and repair. Across species, strategies for stochastic multicolour labelling have greatly facilitated in vivo cell tracking and mapping neuronal connectivity. Yet integrating multi-fluorophore information into the context of developing zebrafish tissues is challenging given their cytoplasmic localization and spectral incompatibility with common fluorescent markers. Inspired by Drosophila Raeppli, we developed FRaeppli (Fish-Raeppli) by expressing bright membrane- or nuclear-targeted fluorescent proteins for efficient cell shape analysis and tracking. High spatiotemporal activation flexibility is provided by the Gal4/UAS system together with Cre/lox and/or PhiC31 integrase. The distinct spectra of the FRaeppli fluorescent proteins allow simultaneous imaging with GFP and infrared subcellular reporters or tissue landmarks. We demonstrate the suitability of FRaeppli for live imaging of complex internal organs, such as the liver, and have tailored hyperspectral protocols for time-efficient acquisition. Combining FRaeppli with polarity markers revealed previously unknown canalicular topologies between differentiating hepatocytes, reminiscent of the mammalian liver, suggesting common developmental mechanisms. The multispectral FRaeppli toolbox thus enables the comprehensive analysis of intricate cellular morphologies, topologies and lineages at single-cell resolution in zebrafish.


Assuntos
Integrases , Peixe-Zebra , Animais , Animais Geneticamente Modificados , Proteínas de Fluorescência Verde/metabolismo , Integrases/metabolismo , Mamíferos/metabolismo , Neurônios/metabolismo , Peixe-Zebra/metabolismo
6.
J Biol Chem ; 299(6): 104730, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37084813

RESUMO

Integration of retroviral DNA into the host genome involves the formation of integrase (IN)-DNA complexes termed intasomes. Further characterization of these complexes is needed to understand their assembly process. Here, we report the single-particle cryo-EM structure of the Rous sarcoma virus (RSV) strand transfer complex (STC) intasome produced with IN and a preassembled viral/target DNA substrate at 3.36 Å resolution. The conserved intasome core region consisting of IN subunits contributing active sites interacting with viral/target DNA has a resolution of 3 Å. Our structure demonstrated the flexibility of the distal IN subunits relative to the IN subunits in the conserved intasome core, similar to results previously shown with the RSV octameric cleaved synaptic complex intasome produced with IN and viral DNA only. An extensive analysis of higher resolution STC structure helped in the identification of nucleoprotein interactions important for intasome assembly. Using structure-function studies, we determined the mechanisms of several IN-DNA interactions critical for assembly of both RSV intasomes. We determined the role of IN residues R244, Y246, and S124 in cleaved synaptic complex and STC intasome assemblies and their catalytic activities, demonstrating differential effects. Taken together, these studies advance our understanding of different RSV intasome structures and molecular determinants involved in their assembly.


Assuntos
Integrases , Vírus do Sarcoma de Rous , Integração Viral , DNA Viral/química , DNA Viral/ultraestrutura , Integrases/química , Integrases/ultraestrutura , Vírus do Sarcoma de Rous/genética , Vírus do Sarcoma de Rous/química , Microscopia Crioeletrônica
7.
Clin Infect Dis ; 2024 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-39324701

RESUMO

BACKGROUND: Sex-specific, long-term, body weight change in persons with HIV (PWH) following switch to regimens containing integrase strand-transfer inhibitors (INSTIs) is unknown. METHODS: We compared PWH enrolled in the MACS/WIHS Combined Cohort Study (2007-2020) who switched/added an INSTI to their antiretroviral therapy (ART) to those remaining on non-INSTI ART and to people without HIV (PWOH), by sex. Follow-up time was time since switch visit (or comparable visit in controls). Linear regression mixed effect models assessed the effects of sex, group (INSTI, non-INSTI, PWOH), and time upon weight and anthropometric measurements (waist, hip, thigh). RESULTS: Of 3464 participants included, women (411 INSTI, 709 Non-INSTI, 818 PWOH) compared to men (223 INSTI, 412 Non-INSTI, 891 PWOH) were younger (47.2 years vs 54.5), majority non-Hispanic Black (65 vs 23%), and had higher mean BMI (31.5 kg/m2 vs 26.9), respectively. Women switching to INSTIs experienced greater absolute and % weight gain compared to men at 5 years: +3.0 kg (95% CI 2.1-3.9) vs +1.8 kg (0.7-2.9) and +4.6% (3.5-5.7) vs +2.3% (1.0-3.6), respectively, [sex*time*study group interaction, p<0.01]. Compared to men, women switching to INSTIs experienced greater hip and thigh circumference gain at 5 years: +2.6 cm (95% CI 1.6-3.6) vs +1.2 cm (0.3-2.1) and +1.5 cm (0.7-2.2) vs -0.2 cm (-0.9, 0.5), respectively, but there were no significant sex differences in waist circumference or waist-hip ratio. CONCLUSIONS: Weight change among PWH over 5 years after switch to INSTI was 2-fold higher in women than men. The cardio-metabolic implications of this difference in weight gain remain unknown.

8.
Clin Infect Dis ; 79(1): 169-176, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-38236137

RESUMO

BACKGROUND: Most international treatment guidelines recommend rapid initiation of antiretroviral therapy (ART) for people newly diagnosed with human immunodeficiency virus (HIV)-1 infection, but experiences with rapid ART initiation remain limited in China. We aimed to evaluate the efficacy and safety of efavirenz (400 mg) plus lamivudine and tenofovir disoproxil fumarate (EFV + 3TC + TDF) versus coformulated bictegravir, emtricitabine, and tenofovir alafenamide (BIC/FTC/TAF) in rapid ART initiation among men who have sex with men (MSM) who have been diagnosed with HIV. METHODS: This multicenter, open-label, randomized clinical trial enrolled MSM aged ≥18 years to start ART within 14 days of confirmed HIV diagnosis. The participants were randomly assigned in a 1:1 ratio to receive EFV (400 mg) + 3TC + TDF or BIC/FTC/TAF. The primary end point was viral suppression (<50 copies/mL) at 48 weeks per US Food and Drug Administration Snapshot analysis. RESULTS: Between March 2021 and July 2022, 300 participants were enrolled; 154 were assigned to receive EFV + 3TC + TDF (EFV group) and 146 BIC/FTC/TAF (BIC group). At week 48, 118 (79.2%) and 140 (95.9%) participants in the EFV and BIC group, respectively, were retained in care with viral suppression, and 24 (16.1%) and 1 (0.7%) participant in the EFV and BIC group (P < .001), respectively, discontinued treatment because of adverse effects, death, or lost to follow-up. The median increase of CD4 count was 181 and 223 cells/µL (P = .020), respectively, for the EFV and BIC group, at week 48. The overall incidence of adverse effects was significantly higher for the EFV group (65.8% vs 37.7%, P < .001). CONCLUSIONS: BIC/FTC/TAF was more efficacious and safer than EFV (400 mg) + 3TC + TDF for rapid ART initiation among HIV-positive MSM in China.


Assuntos
Alcinos , Fármacos Anti-HIV , Benzoxazinas , Ciclopropanos , Emtricitabina , Infecções por HIV , Homossexualidade Masculina , Lamivudina , Tenofovir , Humanos , Masculino , Infecções por HIV/tratamento farmacológico , Adulto , Tenofovir/uso terapêutico , Tenofovir/análogos & derivados , China , Emtricitabina/uso terapêutico , Emtricitabina/administração & dosagem , Ciclopropanos/uso terapêutico , Fármacos Anti-HIV/uso terapêutico , Fármacos Anti-HIV/efeitos adversos , Fármacos Anti-HIV/administração & dosagem , Alcinos/uso terapêutico , Lamivudina/uso terapêutico , Lamivudina/administração & dosagem , Lamivudina/efeitos adversos , Benzoxazinas/uso terapêutico , Alanina/uso terapêutico , Pessoa de Meia-Idade , Compostos Heterocíclicos de 4 ou mais Anéis/uso terapêutico , Compostos Heterocíclicos de 4 ou mais Anéis/efeitos adversos , Compostos Heterocíclicos de 4 ou mais Anéis/administração & dosagem , Contagem de Linfócito CD4 , Dioxolanos/uso terapêutico , Dioxolanos/administração & dosagem , Compostos Heterocíclicos com 3 Anéis/uso terapêutico , Compostos Heterocíclicos com 3 Anéis/efeitos adversos , Compostos Heterocíclicos com 3 Anéis/administração & dosagem , Piperazinas/uso terapêutico , Terapia Antirretroviral de Alta Atividade/métodos , Carga Viral , Adulto Jovem , Combinação de Medicamentos , HIV-1/efeitos dos fármacos , Amidas , Piridonas
9.
BMC Genomics ; 25(1): 568, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38840068

RESUMO

BACKGROUND: Transgenic (Tg) mice are widely used in biomedical research, and they are typically generated by injecting transgenic DNA cassettes into pronuclei of one-cell stage zygotes. Such animals often show unreliable expression of the transgenic DNA, one of the major reasons for which is random insertion of the transgenes. We previously developed a method called "pronuclear injection-based targeted transgenesis" (PITT), in which DNA constructs are directed to insert at pre-designated genomic loci. PITT was achieved by pre-installing so called landing pad sequences (such as heterotypic LoxP sites or attP sites) to create seed mice and then injecting Cre recombinase or PhiC31 integrase mRNAs along with a compatible donor plasmid into zygotes derived from the seed mice. PITT and its subsequent version, improved PITT (i-PITT), overcome disadvantages of conventional Tg mice such as lack of consistent and reliable expression of the cassettes among different Tg mouse lines, and the PITT approach is superior in terms of cost and labor. One of the limitations of PITT, particularly using Cre-mRNA, is that the approach cannot be used for insertion of conditional expression cassettes using Cre-LoxP site-specific recombination. This is because the LoxP sites in the donor plasmids intended for achieving conditional expression of the transgene will interfere with the PITT recombination reaction with LoxP sites in the landing pad. RESULTS: To enable the i-PITT method to insert a conditional expression cassette, we modified the approach by simultaneously using PhiC31o and FLPo mRNAs. We demonstrate the strategy by creating a model containing a conditional expression cassette at the Rosa26 locus with an efficiency of 13.7%. We also demonstrate that inclusion of FLPo mRNA excludes the insertion of vector backbones in the founder mice. CONCLUSIONS: Simultaneous use of PhiC31 and FLP in i-PITT approach allows insertion of donor plasmids containing Cre-loxP-based conditional expression cassettes.


Assuntos
Genoma , Integrases , Camundongos Transgênicos , Animais , Camundongos , Integrases/genética , Integrases/metabolismo , Transgenes , Marcação de Genes/métodos , Técnicas de Transferência de Genes , Plasmídeos/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Mutagênese Insercional
10.
EMBO J ; 39(17): e104337, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32677087

RESUMO

Integration of transposable elements into the genome is mutagenic. Mechanisms targeting integrations into relatively safe locations, hence minimizing deleterious consequences for cell fitness, have emerged during evolution. In budding yeast, integration of the Ty1 LTR retrotransposon upstream of RNA polymerase III (Pol III)-transcribed genes requires interaction between Ty1 integrase (IN1) and AC40, a subunit common to Pol I and Pol III. Here, we identify the Ty1 targeting domain of IN1 that ensures (i) IN1 binding to Pol I and Pol III through AC40, (ii) IN1 genome-wide recruitment to Pol I- and Pol III-transcribed genes, and (iii) Ty1 integration only at Pol III-transcribed genes, while IN1 recruitment by AC40 is insufficient to target Ty1 integration into Pol I-transcribed genes. Swapping the targeting domains between Ty5 and Ty1 integrases causes Ty5 integration at Pol III-transcribed genes, indicating that the targeting domain of IN1 alone confers Ty1 integration site specificity.


Assuntos
Integrases/metabolismo , RNA Polimerase III/metabolismo , RNA Polimerase I/metabolismo , RNA de Transferência/genética , Retroelementos , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Integrases/genética , RNA Polimerase I/genética , RNA Polimerase III/genética , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética
11.
BMC Biotechnol ; 24(1): 44, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38926833

RESUMO

BACKGROUND: Mammalian display is an appealing technology for therapeutic antibody development. Despite the advantages of mammalian display, such as full-length IgG display with mammalian glycosylation and its inherent ability to select antibodies with good biophysical properties, the restricted library size and large culture volumes remain challenges. Bxb1 serine integrase is commonly used for the stable genomic integration of antibody genes into mammalian cells, but presently lacks the efficiency required for the display of large mammalian display libraries. To increase the Bxb1 integrase-mediated stable integration efficiency, our study investigates factors that potentially affect the nuclear localization of Bxb1 integrase. METHODS: In an attempt to enhance Bxb1 serine integrase-mediated integration efficiency, we fused various nuclear localization signals (NLS) to the N- and C-termini of the integrase. Concurrently, we co-expressed multiple proteins associated with nuclear transport to assess their impact on the stable integration efficiency of green fluorescent protein (GFP)-encoding DNA and an antibody display cassette into the genome of Chinese hamster ovary (CHO) cells containing a landing pad for Bxb1 integrase-mediated integration. RESULTS: The nucleoplasmin NLS from Xenopus laevis, when fused to the C-terminus of Bxb1 integrase, demonstrated the highest enhancement in stable integration efficiency among the tested NLS fusions, exhibiting over a 6-fold improvement compared to Bxb1 integrase lacking an NLS fusion. Subsequent additions of extra NLS fusions to the Bxb1 integrase revealed an additional 131% enhancement in stable integration efficiency with the inclusion of two copies of C-terminal nucleoplasmin NLS fusions. Further improvement was achieved by co-expressing the Ran GTPase-activating protein (RanGAP). Finally, to validate the applicability of these findings to more complex proteins, the DNA encoding the membrane-bound clinical antibody abrilumab was stably integrated into the genome of CHO cells using Bxb1 integrase with two copies of C-terminal nucleoplasmin NLS fusions and co-expression of RanGAP. This approach demonstrated over 14-fold increase in integration efficiency compared to Bxb1 integrase lacking an NLS fusion. CONCLUSIONS: This study demonstrates that optimizing the NLS sequence fusion for Bxb1 integrase significantly enhances the stable genomic integration efficiency. These findings provide a practical approach for constructing larger libraries in mammalian cells through the stable integration of genes into a genomic landing pad.


Assuntos
Cricetulus , Integrases , Sinais de Localização Nuclear , Animais , Células CHO , Integrases/metabolismo , Integrases/genética , Sinais de Localização Nuclear/metabolismo , Sinais de Localização Nuclear/genética , Núcleo Celular/metabolismo , Núcleo Celular/genética , Serina/metabolismo , Proteínas de Fluorescência Verde/metabolismo , Proteínas de Fluorescência Verde/genética , Cricetinae , Xenopus laevis/metabolismo
12.
Brief Bioinform ; 23(6)2022 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-36215051

RESUMO

Antiretroviral peptides are a kind of bioactive peptides that present inhibitory activity against retroviruses through various mechanisms. Among them, viral integrase inhibitory peptides (VINIPs) are a class of antiretroviral peptides that have the ability to block the action of integrase proteins, which is essential for retroviral replication. As the number of experimentally verified bioactive peptides has increased significantly, the lack of in silico machine learning approaches can effectively predict the peptides with the integrase inhibitory activity. Here, we have developed the first prediction model for identifying the novel VINIPs using the sequence characteristics, and the hybrid feature set was considered to improve the predictive ability. The performance was evaluated by 5-fold cross-validation based on the training dataset, and the result indicates the proposed model is capable of predicting the VINIPs, with a sensitivity of 85.82%, a specificity of 88.81%, an accuracy of 88.37%, a balanced accuracy of 87.32% and a Matthews correlation coefficient value of 0.64. Most importantly, the model also consistently provides effective performance in independent testing. To sum up, we propose the first computational approach for identifying and characterizing the VINIPs, which can be considered novel antiretroviral therapy agents. Ultimately, to facilitate further research and development, iDVIP, an automatic computational tool that predicts the VINIPs has been developed, which is now freely available at http://mer.hc.mmh.org.tw/iDVIP/.


Assuntos
Infecções por HIV , Integrases , Humanos , Sequência de Aminoácidos , Peptídeos/farmacologia , Peptídeos/química , Proteínas/química
13.
Appl Environ Microbiol ; 90(4): e0236323, 2024 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-38551351

RESUMO

Microbial biosensors that convert environmental information into real-time visual outputs are limited in their sensing abilities in complex environments, such as soil and wastewater, due to optical inaccessibility. Biosensors that could record transient exposure to analytes within a large time window for later retrieval represent a promising approach to solve the accessibility problem. Here, we test the performance of recombinase-memory biosensors that sense a sugar (arabinose) and a microbial communication molecule (3-oxo-C12-L-homoserine lactone) over 8 days (~70 generations) following analyte exposure. These biosensors sense the analyte and trigger the expression of a recombinase enzyme which flips a segment of DNA, creating a genetic memory, and initiates fluorescent protein expression. The initial designs failed over time due to unintended DNA flipping in the absence of the analyte and loss of the flipped state after exposure to the analyte. Biosensor performance was improved by decreasing recombinase expression, removing the fluorescent protein output, and using quantitative PCR to read out stored information. Application of memory biosensors in wastewater isolates achieved memory of analyte exposure in an uncharacterized Pseudomonas isolate. By returning these engineered isolates to their native environments, recombinase-memory systems are expected to enable longer duration and in situ investigation of microbial signaling, cross-feeding, community shifts, and gene transfer beyond the reach of traditional environmental biosensors.IMPORTANCEMicrobes mediate ecological processes over timescales that can far exceed the half-lives of transient metabolites and signals that drive their collective behaviors. We investigated strategies for engineering microbes to stably record their transient exposure to a chemical over many generations through DNA rearrangements. We identify genetic architectures that improve memory biosensor performance and characterize these in wastewater isolates. Memory biosensors are expected to be useful for monitoring cell-cell signals in biofilms, detecting transient exposure to chemical pollutants, and observing microbial cross-feeding through short-lived metabolites within cryptic methane, nitrogen, and sulfur cycling processes. They will also enable in situ studies of microbial responses to ephemeral environmental changes, or other ecological processes that are currently challenging to monitor non-destructively using real-time biosensors and analytical instruments.


Assuntos
Técnicas Biossensoriais , Águas Residuárias , Recombinases , DNA , Pseudomonas , Corantes
14.
HIV Med ; 2024 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-39197859

RESUMO

INTRODUCTION: Prevention of cardiovascular disease is a major issue in the current management of people living with HIV. Concern is growing about the metabolic impact of integrase strand transfer inhibitors (INSTIs), which could lead to an increased risk of diabetes, but the data are conflicting. This is an updated version of our previous analysis, with longer follow-up and new molecules. METHODS: We retrospectively evaluated the incidence of new-onset diabetes in people living with HIV starting combined antiretroviral therapy with an INSTI compared with non-nucleoside reverse transcriptase inhibitors and protease inhibitors. Data were collected from the Dat'AIDS cohort study, a collaboration of 30 HIV treatment centres in France. We used a propensity score-based inverse probability of treatment weighting approach to adjust for baseline characteristics between the two groups (INSTI and non-INSTI). RESULTS: Between 2009 and 2021, a total of 12 150 people living with HIV were included. The incidence of diabetes was higher in the INSTI group than in the non-INSTI group (hazard ratio 1.38; 95% confidence interval 1.07-1.77; p = 0.012). Regardless of the third drug, but to a greater extent for INSTIs, we observed a peak of new-onset diabetes in the year following initiation of combined antiretroviral therapy. CONCLUSIONS: The incidence of diabetes was higher in people treated with integrase inhibitors than in those receiving other third agents. This increased risk occurred both during the first year of treatment and in the longer term.

15.
HIV Med ; 25(2): 188-200, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37776199

RESUMO

INTRODUCTION: The impact of specific policies on HIV care has been scarcely investigated. In this study we aimed to analyze the impact of the Treatment For All policy (TFA-2013) and the adoption of integrase strand transfer inhibitors (INSTIs-2017) as first-line therapy on clinical indicators of people living with HIV (PLHIV) in Brazil. METHODS: We assessed the public database of Brazil's Ministry of Health and extracted data from 2009 to 2019. We investigated the impact of TFA and INSTIs with a time-series analysis of four health indicators in PLHIV: antiretroviral treatment (ART) initiation with a CD4+ count >500/mm3 ; ART initiation <1 month after the first CD4+ measurement; viral load suppression (VLS); and treatment adherence. We explored trends over time by gender, age, macroregion of residency and municipal-level social vulnerability index. RESULTS: We included 753 316 PLHIV in 2019. Most were males (64.81%) in the 30-49 years age category (50.86%). We observed an overall improvement in all HIV clinical indicators, with notable impact of TFA on timely ART initiation and VLS, and mild impact of INSTIs on treatment adherence. Such improvements were heterogeneous, with remarkable gaps in gender, age and socioeconomic groups that have persisted over time. Indicators point to inferior outcomes among children, older adults, women and people living in socially vulnerable locations. CONCLUSIONS: Recent Brazilian public policies have had positive impacts on key HIV clinical indicators. However, our results highlight the need for specific policies to improve HIV care for children, older adults, women and socially vulnerable groups.


Assuntos
Síndrome da Imunodeficiência Adquirida , Fármacos Anti-HIV , Infecções por HIV , Masculino , Criança , Humanos , Feminino , Idoso , Síndrome da Imunodeficiência Adquirida/tratamento farmacológico , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Brasil/epidemiologia , Fatores Sociodemográficos , Antirretrovirais/uso terapêutico , Política Pública , Carga Viral , Política de Saúde , Fármacos Anti-HIV/uso terapêutico
16.
HIV Med ; 25(3): 361-369, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37990782

RESUMO

BACKGROUND: People living with HIV (PLWH) and receiving antiretroviral therapy (ART) have a goal of achieving and maintaining viral suppression; however, the existence of PLWH that show events of low-level viremia (LLV) between 50 and 1000 copies/mL and with different virological consequences have been observed. Moreover, some reports indicate that LLV status can lead to residual immune activation and inflammation, leading to a higher occurrence of non-AIDS-defining events (nADEs) and other adverse clinical outcomes. Until now, however, published data have shown controversial results that hinder understanding of this phenomenon's actual cause(s) and origin(s). Integrase strand transfer inhibitors (INSTIs)-based therapies could lead to lower LLV over time and, therefore, more effective virological control. OBJECTIVES: This review aims to assess recent findings to provide a view of the clinical significance and management of low-level HIV viremia in the era of INSTIs.


Assuntos
Fármacos Anti-HIV , Infecções por HIV , Inibidores de Integrase de HIV , Humanos , Fármacos Anti-HIV/uso terapêutico , Infecções por HIV/tratamento farmacológico , Viremia/tratamento farmacológico , Relevância Clínica , Carga Viral , Integrases/uso terapêutico , Inibidores de Integrase de HIV/uso terapêutico
17.
HIV Med ; 2024 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-39135323

RESUMO

INTRODUCTION: The issue of whether integrase inhibitors (INSTIs) may confer a higher risk of paradoxical tuberculosis-related immune reconstitution inflammatory syndrome (TB-IRIS) compared with other classes of antiretroviral in people with HIV with a profound level of immunosuppression remains insufficiently explored. We aimed to assess whether such a higher risk exists by examining a cohort of patients with TB-HIV initiating antiretroviral therapy (ART) in Hong Kong. METHODS: This was a retrospective review of 133 patients registered in the TB-HIV Registry of the Department of Health during the period 2014-2021. RESULTS: Sixteen of 70 patients (22.9%; 95% confidence interval [CI] 13.0-32.7) and 14 of 63 patients (22.2%; 95% CI 12.0-32.5) from the INSTI and non-INSTI groups experienced TB-IRIS (p = 0.920). The median intervals between ART initiation and IRIS among patients from the two groups were similar (3 weeks [interquartile range IQR 2.0-7.8] vs. 4 weeks [IQR 2.0-5.1], p = 0.620). The proportion of patients requiring steroid therapy were similar, as were the hospitalization rates. There was no IRIS-related death in either group. The risk of TB-IRIS with INSTI versus non-INSTI was also similar in a stratified analysis in a subgroup of patients with a baseline CD4 count of <50 µL (10/33 [30.3%; 95% CI 14.6-46.0] vs. 10/22 [45.5%; 95% CI 24.7-66.3], p = 0.252) and another subgroup of patients with ART initiated within 4 weeks of anti-TB treatment (10/26 [38.5%; 95% CI 19.8-57.2] vs. 10/23 [43.5%; 95% CI 23.2-63.7], p = 0.721). CONCLUSION: Our cohort study did not offer support for an increased risk of TB-IRIS with INSTIs compared with non-INSTIs, even in severely immunocompromised people with HIV.

18.
Transgenic Res ; 2024 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-39158822

RESUMO

The application of rapidly growing CRISPR toolboxes and methods has great potential to transform biomedical research. Here, we provide a snapshot of up-to-date CRISPR toolboxes, then critically discuss the promises and hurdles associated with CRISPR-based nuclear genome editing, epigenome editing, and mitochondrial editing. The technical challenges and key solutions to realize epigenome editing in vivo, in vivo base editing and prime editing, mitochondrial editing in complex tissues and animals, and CRISPR-associated transposases and integrases in targeted genomic integration of very large DNA payloads are discussed. Lastly, we discuss the latest situation of the CRISPR/Cas9 clinical trials and provide perspectives on CRISPR-based gene therapy. Apart from technical shortcomings, ethical and societal considerations for CRISPR applications in human therapeutics and research are extensively highlighted.

19.
Br J Clin Pharmacol ; 90(1): 264-273, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37602480

RESUMO

AIMS: Dolutegravir (DTG) and rilpivirine (RPV) dual therapy is now recommended as a switch option in virologically suppressed HIV patients. Literature suggests that virological failure with dual therapy could possibly relate to subtherapeutic drug concentrations. In this study, we aimed at describing the DTG and RPV trough plasma concentrations (Cmin) and plasma HIV-1 RNA viral load (VL) during maintenance dual therapy. METHODS: We performed a retrospective analysis of DTG and RPV therapeutic drug monitoring in people living with HIV/AIDS (PLWHA) with dual therapy in 9 French centres. DTG and RPV trough plasma concentrations were estimated using a Bayesian approach to predict Cmin. The relationship between the pharmacokinetics of DTG and RPV and VL > 50 copies (cp)/mL was explored using joint nonlinear mixed models. The frequency of subtherapeutic threshold (DTG Cmin below 640 ng/mL and RPV Cmin below 50 ng/mL) were compared between PLWHA presenting VL > 50 cp/mL or not during the study. RESULTS: At baseline, 209 PLWHA were enrolled in the study. At week 48, 19 people living with HIV/AIDS (9.1%) discontinued their treatment and 15 PLWHA (7.1%) exhibited VL > 50 cp/mL. Six PLWHA out of 15 (40.0%) with VL > 50 cp/mL during the follow-up had at least 1 Cmin below the respective thresholds while only 26/194 patients (13.4%) without virological replication had at least 1 concentration below the threshold (P = .015). CONCLUSION: A majority of PLWHA receiving DTG/RPV maintenance dual therapy demonstrated VL < 50 cp/mL but virological replication was more frequent in people living with HIV/AIDS with subtherapeutic Cmin.


Assuntos
Síndrome da Imunodeficiência Adquirida , Fármacos Anti-HIV , Infecções por HIV , HIV-1 , Humanos , Fármacos Anti-HIV/uso terapêutico , Estudos Retrospectivos , Síndrome da Imunodeficiência Adquirida/tratamento farmacológico , Teorema de Bayes , Monitoramento de Medicamentos , Rilpivirina/uso terapêutico , Oxazinas , Piridonas/uso terapêutico , Compostos Heterocíclicos com 3 Anéis/efeitos adversos , Carga Viral
20.
Bioorg Med Chem Lett ; 111: 129902, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39059564

RESUMO

Integrase strand transfer inhibitors (INSTIs) are the most prescribed anchor drug in antiretroviral therapy. Today, there is an increasing need for long-acting treatment of HIV-1 infection. Improving drug pharmacokinetics and anti-HIV-1 activity are key to developing more robust inhibitors suitable for long-acting formulations, but 2nd-generation INSTIs have chiral centers, making it difficult to conduct further exploration. In this study, we designed aza-tricyclic and aza-bicyclic carbamoyl pyridone scaffolds which are devoid of the problematic hemiaminal stereocenter present in dolutegravir (DTG). This scaffold hopping made it easy to introduce several substituents, and evolving structure-activity studies using these scaffolds resulted in several leads with promising properties.


Assuntos
Desenho de Fármacos , Inibidores de Integrase de HIV , Integrase de HIV , HIV-1 , Piridonas , Humanos , Compostos Aza/química , Compostos Aza/farmacologia , Compostos Aza/síntese química , Relação Dose-Resposta a Droga , Integrase de HIV/metabolismo , Inibidores de Integrase de HIV/farmacologia , Inibidores de Integrase de HIV/química , Inibidores de Integrase de HIV/síntese química , HIV-1/efeitos dos fármacos , Estrutura Molecular , Piridonas/química , Piridonas/farmacologia , Piridonas/síntese química , Relação Estrutura-Atividade , Integrases/química , Integrases/metabolismo , Integrases/farmacocinética
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