Carry-over effects of resource polymorphisms

An individual’s early-life environment or phenotype frequently influence its adult traits. Recently, scientists have begun to examine carry-over effects, how factors at one life stage can impact an individual’s performance in the following stages, to better understand how factors during development impact adult phenotypes. Carry-over effects are especially important to study in organisms with complex life cycles since these often undergo dramatic tissue reorganization that have the possibility of uncoupling and resetting early life experiences. Here I examine carry-over effects on a resource polymorphic species to better understand how early life phenotype and environment carry over across life stages. Using spadefoot toads as the model system, I examine in Chapter II whether environment- or phenotype-dependent ‘carry-over effects’, respectively, are associated with alternative, environmentally induced, phenotypes. I ask whether carry-over effects are evident in terms of size and timing to metamorphosis, size and timing to sexual maturity and survival differences. I find that pond environment is the larger predictor of carry-over effects. Larval morphotype has important impacts in terms of timing to metamorphosis and sexual maturity. In Chapter III, I evaluate whether there are behavioral differences carried over post-metamorphosis. I evaluate foraging behavior in particular since, post-metamorphosis, spadefoot toads converge on diet, so I would not expect toads to differ when trying to capture the same food items. Interestingly, I found that toads who were previously the carnivorous morphotype were more efficient foragers and consumed more prey items. Finally, in Chapter IV, I examine whether resource polymorphisms at the larval stage are accompanied by anatomical differences, and if these persist to adulthood. Any anatomical differences could be indicative of physiological differences in how resources are used and stored. I found that carnivore and omnivores differ in liver sizes and these differences are still present at the juvenile stage and in wild caught populations. Together my research shows that there are carry-over effects of early life experiences in spadefoot toads.Doctor of Philosoph

Dextran sulfate from Leuconostoc mesenteroides B512F exerts potent antiviral activity against SARS-CoV-2 in vitro and in vivo

SARS–CoV–2; Dextran sulfate; NebulizationSARS–CoV–2; Sulfato de dextrano; NebulizaciónSARS–CoV–2; Sulfat de dextrano; NebulitzacióThe emergent human coronavirus SARS-CoV-2 and its resistance to current drugs makes the need for new potent treatments for COVID-19 patients strongly necessary. Dextran sulfate (DS) polysaccharides have long demonstrated antiviral activity against different enveloped viruses in vitro. However, their poor bioavailability has led to their abandonment as antiviral candidates. Here, we report for the first time the broad-spectrum antiviral activity of a DS-based extrapolymeric substance produced by the lactic acid bacterium Leuconostoc mesenteroides B512F. Time of addition assays with SARS-CoV-2 pseudoviruses in in vitro models confirm the inhibitory activity of DSs in the early stages of viral infection (viral entry). In addition, this exopolysaccharide substance also reports broad-spectrum antiviral activity against several enveloped viruses such as SARS-CoV-2, HCoV229E, HSV-1, in in vitro models and in human lung tissue. The toxicity and antiviral capacity of DS from L. mesenteroides was tested in vivo in mouse models which are susceptible to SARS-CoV-2 infection. The described DS, administered by inhalation, a new route of administration for these types of polymers, shows strong inhibition of SARS-CoV-2 infection in vivo, significantly reducing animal mortality and morbidity at non-toxic doses. Therefore, we suggest that it may be considered as a potential candidate for antiviral therapy against SARS-CoV-2.Financial support for the study was provided by the REACT-EU 2021 grant from Comunidad de Madrid to the Project COVTRAVI-19-CM, Plataformas y modelos preclínicos para el abordaje multidisciplinar en COVID-19 y en respuesta a futuras pandemias

Mitochondrial dysfunction, lipids metabolism, and amino acid biosynthesis are key pathways for COVID-19 recovery

Biological sciences; Human metabolismCiències biològiques; Metabolisme humàCiencias biológicas; Metabolismo humanoThe metabolic alterations caused by SARS-CoV-2 infection reflect disease progression. To analyze molecules involved in these metabolic changes, a multiomics study was performed using plasma from 103 patients with different degrees of COVID-19 severity during the evolution of the infection. With the increased severity of COVID-19, changes in circulating proteomic, metabolomic, and lipidomic profiles increased. Notably, the group of severe and critical patients with high HRG and ChoE (20:3) and low alpha-ketoglutaric acid levels had a high chance of unfavorable disease evolution (AUC = 0.925). Consequently, patients with the worst prognosis presented alterations in the TCA cycle (mitochondrial dysfunction), lipid metabolism, amino acid biosynthesis, and coagulation. Our findings increase knowledge regarding how SARS-CoV-2 infection affects different metabolic pathways and help in understanding the future consequences of COVID-19 to identify potential therapeutic targets.This work has been developed in the framework of the COVIDOMICS’ project supported by Direcció General de Recerca i Innovació en Salut (DGRIS), Departament de Salut, Generalitat de Catalunya (PoC-6-17 and PoC1-5). The research was also supported by the Programa de Suport als Grups de Recerca AGAUR (2021SGR01404), the SPANISH AIDS Research Network [RD16/0025/0006]-ISCIII-FEDER (Spain) and the CIBER -Consorcio Centro de Investigación Biomédica en Red- (CB21/13/00020 and CB07/08/0012), Instituto de Salud Carlos III, Ministerio de Ciencia e Innovación and Unión Europea – NextGenerationEU. FV is supported by grants from the Programa de Intensificación de Investigadores (INT20/00031)-ISCIII and by “Premi a la Trajectòria Investigadora dels Hospitals de l’ICS 2018”. AR is supported by a grant from IISPV through the project “2019/IISPV/05” (Boosting Young Talent), by GeSIDA through the “III Premio para Jóvenes Investigadores 2019” and by the Instituto de Salud Carlos III (ISCIII) under grant agreement “CP19/00146” through the Miguel Servet Program. Finally, this study would not have been possible without the generous collaboration of all the patients and their families and medical and nursing staff who have taken part in the project. We particularly acknowledge the collaboration of the Departments of Preventive Medicine and Epidemiology, Internal Medicine, Critical Care, Emergency, Occupational Health, Laboratory Medicine and Molecular Biology, and BioBank-IISPV (B.0000853 + B.0000854) integrated into the Spanish National Biobanks Platform (PT20/00197), CERCA Program (Generalitat de Catalunya) and IISPV, for their collaboration

Schlafen 12 restricts HIV-1 latency reversal by a codon-usage dependent post-transcriptional block in CD4+ T cells

HIV infections; Restriction factorsInfecciones por VIH; Factores de restricciónInfeccions pel VIH; Factors de restriccióLatency is a major barrier towards virus elimination in HIV-1-infected individuals. Yet, the mechanisms that contribute to the maintenance of HIV-1 latency are incompletely understood. Here we describe the Schlafen 12 protein (SLFN12) as an HIV-1 restriction factor that establishes a post-transcriptional block in HIV-1-infected cells and thereby inhibits HIV-1 replication and virus reactivation from latently infected cells. The inhibitory activity is dependent on the HIV-1 codon usage and on the SLFN12 RNase active sites. Within HIV-1-infected individuals, SLFN12 expression in PBMCs correlated with HIV-1 plasma viral loads and proviral loads suggesting a link with the general activation of the immune system. Using an RNA FISH-Flow HIV-1 reactivation assay, we demonstrate that SLFN12 expression is enriched in infected cells positive for HIV-1 transcripts but negative for HIV-1 proteins. Thus, codon-usage dependent translation inhibition of HIV-1 proteins participates in HIV-1 latency and can restrict the amount of virus release after latency reversal.This work was supported by following grants: M.K.I., JSPS Oversea Research Fellowship and Takeda Science Foundation; A.E.C., PT17/0009/0019 (ISCIII/MINECO and FEDER); M.J.B., RTI2018-101082-B-I00 and PID2021-123321OB-I00 [MINECO/FEDER]), and the Miguel Servet program by ISCIII (CP17/00179 and CPII22/00005); C.B., M.R.R., C.D.C., European Union’s Horizon 2020 research and innovation program under grant agreement 681137-EAVI2020 and NIH grant P01-AI131568; J.D., the Spanish Ministry of Science and Innovation (PID2019106959RB-I00/AEI/10.13039/501100011033); A.M., the Spanish Ministry of Science and Innovation (PID2019-106323RB-I00 AEI//10.13039/501100011033) and the institutional “María de Maeztu” Programme for Units of Excellence in R&D (CEX2018-000792-M)

HIV-1 persistence in CD4+ T cells with stem cell-like properties

Cellular HIV-1 reservoirs that persist despite antiretroviral treatment are incompletely defined. We show that during suppressive antiretroviral therapy, CD4+ T memory stem cells (TSCM) harbor high per-cell levels of HIV-1 DNA, and make increasing contributions to the total viral CD4+ T cell reservoir over time. Moreover, phylogenetic studies suggested long-term persistence of viral quasispecies in CD4+ TSCM cells. Thus, HIV-1 may exploit stem cell characteristics of cellular immune memory to promote long-term viral persistence

CD32 is expressed on cells with transcriptionally active HIV but does not enrich for HIV DNA in resting T cells

The persistence of HIV reservoirs, including latently infected, resting CD4+ T cells, is the major obstacle to cure HIV infection. CD32a expression was recently reported to mark CD4+ T cells harboring a replication-competent HIV reservoir during antiretroviral therapy (ART) suppression. We aimed to determine whether CD32 expression marks HIV latently or transcriptionally active infected CD4+ T cells. Using peripheral blood and lymphoid tissue of ART-treated HIV+ or SIV+ subjects, we found that most of the circulating memory CD32+ CD4+ T cells expressed markers of activation, including CD69, HLA-DR, CD25, CD38, and Ki67, and bore a TH2 phenotype as defined by CXCR3, CCR4, and CCR6. CD32 expression did not selectively enrich for HIV- or SIV-infected CD4+ T cells in peripheral blood or lymphoid tissue; isolated CD32+ resting CD4+ T cells accounted for less than 3% of the total HIV DNA in CD4+ T cells. Cell-associated HIV DNA and RNA loads in CD4+ T cells positively correlated with the frequency of CD32+ CD69+ CD4+ T cells but not with CD32 expression on resting CD4+ T cells. Using RNA fluorescence in situ hybridization, CD32 coexpression with HIV RNA or p24 was detected after in vitro HIV infection (peripheral blood mononuclear cell and tissue) and in vivo within lymph node tissue from HIV-infected individuals. Together, these results indicate that CD32 is not a marker of resting CD4+ T cells or of enriched HIV DNA–positive cells after ART; rather, CD32 is predominately expressed on a subset of activated CD4+ T cells enriched for transcriptionally active HIV after long-term ART

Impact of very early antiretroviral therapy during acute HIV infection on long-term immunovirological outcomes

Acute HIV infection; Antiretroviral treatment; Immune recoveryInfección aguda por VIH; Tratamiento antirretroviral; Recuperación inmunitariaInfecció aguda per VIH; Tractament antiretroviral; Recuperació immunitàriaObjectives We aimed to determine if starting antiretroviral therapy (ART) in the first 30 days after acquiring HIV infection has an impact on immunovirological response. Methods Observational, ambispective study including 147 patients with confirmed acute HIV infection (January/1995-August/2022). ART was defined as very early (≤30 days after the estimated date of infection), early (31-180 days), and late (>180 days). We compared time to viral suppression (viral load [VL] <50 copies/ml) and immune recovery (IR) (CD4+/CD8+ ratio ≥1) according to the timing and type of ART using survival analysis. Results ART was started in 140 (95.2%) patients. ART was very early in 24 (17.1%), early in 77 (55.0%), and late in 39 (27.9%) cases. Integrase strand transfer inhibitor (INSTI)-based regimens were the most used in both the overall population (65%) and the very early ART group (23/24, 95.8%). Median HIV VL and CD4+/CD8+ ratio pre-ART were higher in the very early ART group (P <0.05). Patients in the very early and early ART groups and treated with INSTI-based regimens achieved IR earlier (P <0.05). Factors associated with faster IR were the CD4+/CD8+ ratio pre-ART (hazard ratio: 9.3, 95% CI: 3.1-27.8, P <0.001) and INSTI-based regimens (hazard ratio: 2.4, 95% CI: 1.3-4.2, P = 0.003). Conclusions The strongest predictors of IR in patients who start ART during AHI are the CD4+/CD8+ ratio pre-ART and INSTI-based ART regimens.This work was founded by Instituto de Salud Carlos III (Acción Estratégica en Salud) and Fondo Europeo de Desarrollo Regional (FEDER) through grant PI20/00823. The study was also supported by the Spanish Network for AIDS Research (RIS) through the Instituto de Salud Carlos III – Red Temática de Investigación Cooperativa en Sida (RD06/006, RD12/0017/0018 and RD16/0002/0006) as part of the Plan Nacional R+D+I and by ISCIII Subdirección General de Evaluación and Fondo Europeo de Desarrollo Regional (FEDER). For this project, PS has received a grant from the Catalan Society of Infectious Diseases and Clinical Microbiology (SCMIMC) funded by ViiV Healthcare. MJB is supported by the Miguel Servet program funded by the Spanish Health Institute Carlos III (CPII22/00005). The funders had no role in the study design, data collection, and interpretation, or the decision to submit the work for publication

KLRG1 expression on natural killer cells is associated with HIV persistence, and its targeting promotes the reduction of the viral reservoir

HIV infection; HIV reservoir; ImmunotherapyInfección por VIH; Reservorio de VIH; InmunoterapiaInfecció per VIH; Reservori de VIH; ImmunoteràpiaHuman immunodeficiency virus (HIV) infection induces immunological dysfunction, which limits the elimination of HIV-infected cells during treated infection. Identifying and targeting dysfunctional immune cells might help accelerate the purging of the persistent viral reservoir. Here, we show that chronic HIV infection increases natural killer (NK) cell populations expressing the negative immune regulator KLRG1, both in peripheral blood and lymph nodes. Antiretroviral treatment (ART) does not reestablish these functionally impaired NK populations, and the expression of KLRG1 correlates with active HIV transcription. Targeting KLRG1 with specific antibodies significantly restores the capacity of NK cells to kill HIV-infected cells, reactivates latent HIV present in CD4+ T cells co-expressing KLRG1, and reduces the intact HIV genomes in samples from ART-treated individuals. Our data support the potential use of immunotherapy against the KLRG1 receptor to impact the viral reservoir during HIV persistence.The project leading to these results has received funding from “la Caixa” Banking Foundation under the project code LCF/PR/HR20-00218. This study was also supported by the Agencia Estatal de Investigación project PID2021-123321OB-I00 funded by MCIN/AEI/10.13039/501100011033/FEDER, UE; The Spanish “Ministerio de Economia y Competitividad, Instituto de Salud Carlos III” (ISCIII, PI20/00160); and the Gilead fellowships GLD19/00084, GLD18/00008, GLD21-00049, and GLD22/00152. Part of the methodology was developed with the support of the grant 202104-30-31 from Fundació la Marató de TV3. M.B. is supported by the Miguel Servet program funded by the Spanish Health Institute Carlos III (CPII22/00005). A.A.-G. was supported by the Spanish Secretariat of Science and Innovation Ph.D. fellowship (BES-2016-076382). D.P. was supported by the VHIR Ph.D programme 2020. Spanish Secretariat of Science and Innovation Ph.D. fellowship. E.M.G. was supported by the Ramón y Cajal Program (RYC2018-024374-I) funded by the Spanish Secretariat of Science and Innovation, by the Comunidad de Madrid Talento Program (2017-T1/BMD-5396), and by the project PID2021-127899OB-I00 funded by MCIN /AEI /10.13039/501100011033/ FEDER, UE. We thank Dr. Joan Puñet from the flow cytometry core at the Vall d’Hebron Research Institute for his technical and scientific expertise. The funders had no role in study design, data collection, and analysis, the decision to publish, or preparation of the manuscript

Potent Cell-Intrinsic Immune Responses in Dendritic Cells Facilitate HIV-1-Specific T Cell Immunity in HIV-1 Elite Controllers

The majority of HIV-1 elite controllers (EC) restrict HIV-1 replication through highly functional HIV-1-specific T cell responses, but mechanisms supporting the evolution of effective HIV-1-specific T cell immunity in these patients remain undefined. Cytosolic immune recognition of HIV-1 in conventional dendritic cells (cDC) can facilitate priming and expansion of HIV-1-specific T cells; however, HIV-1 seems to be able to avoid intracellular immune recognition in cDCs in most infected individuals. Here, we show that exposure of cDCs from EC to HIV-1 leads to a rapid and sustained production of type I interferons and upregulation of several interferon-stimulated effector genes. Emergence of these cell-intrinsic immune responses was associated with a reduced induction of SAMHD1 and LEDGF/p75, and an accumulation of viral reverse transcripts, but inhibited by pharmacological blockade of viral reverse transcription or siRNA-mediated silencing of the cytosolic DNA sensor cGAS. Importantly, improved cell-intrinsic immune recognition of HIV-1 in cDCs from elite controllers translated into stronger abilities to stimulate and expand HIV-1-specific CD8 T cell responses. These data suggest an important role of cell-intrinsic type I interferon secretion in dendritic cells for the induction of effective HIV-1-specific CD8 T cells, and may be helpful for eliciting functional T cell immunity against HIV-1 for preventative or therapeutic clinical purposes

Schlafen 12 restricts HIV-1 latency reversal by a codon-usage dependent post-transcriptional block in CD4+ T cells

Latency is a major barrier towards virus elimination in HIV-1-infected individuals. Yet, the mechanisms that contribute to the maintenance of HIV-1 latency are incompletely understood. Here we describe the Schlafen 12 protein (SLFN12) as an HIV-1 restriction factor that establishes a post-transcriptional block in HIV-1-infected cells and thereby inhibits HIV-1 replication and virus reactivation from latently infected cells. The inhibitory activity is dependent on the HIV-1 codon usage and on the SLFN12 RNase active sites. Within HIV-1-infected individuals, SLFN12 expression in PBMCs correlated with HIV-1 plasma viral loads and proviral loads suggesting a link with the general activation of the immune system. Using an RNA FISH-Flow HIV-1 reactivation assay, we demonstrate that SLFN12 expression is enriched in infected cells positive for HIV-1 transcripts but negative for HIV-1 proteins. Thus, codon-usage dependent translation inhibition of HIV-1 proteins participates in HIV-1 latency and can restrict the amount of virus release after latency reversal.We thank Drs Yingying Li, Feng Gao and Beatrice H. Hahn for providing codon-optimized HIV-1 Gag expression vector, Drs James Hoxie and Susan Zolla-Pazner for supplying anti-Nef and -p24 antibodies, respectively through the NIH AIDS reagent program. We also thank Dr Song Gao for providing SLFN13-tRNA structure information, and Dr Maria-Eugenia Gas Lopez and Dr Ester Gea-Mallorquí for advise. This work was supported by following grants: M.K.I., JSPS Oversea Research Fellowship and Takeda Science Foundation; A.E.C., PT17/0009/0019 (ISCIII/MINECO and FEDER); M.J.B., RTI2018-101082-B-I00 and PID2021-123321OB-I00 [MINECO/FEDER]), and the Miguel Servet program by ISCIII (CP17/00179 and CPII22/00005); C.B., M.R.R., C.D.C., European Union’s Horizon 2020 research and innovation program under grant agreement 681137-EAVI2020 and NIH grant P01-AI131568; J.D., the Spanish Ministry of Science and Innovation (PID2019106959RB-I00/AEI/10.13039/501100011033); A.M., the Spanish Ministry of Science and Innovation (PID2019-106323RB-I00 AEI//10.13039/501100011033) and the institutional “María de Maeztu” Programme for Units of Excellence in R&D (CEX2018-000792-M).info:eu-repo/semantics/publishedVersio