Biology subjects

Genesca, M.

Publications and source records attributed to Genesca, M..

10 recordsLinked to original sources

bioRxiv2026

Site-Specific Entry Factors Define Cellular Susceptibility to SARS-CoV-2 in Human Tissues

SARS-CoV-2 primarily infects the respiratory epithelium through entry factors ACE2 and TMPRSS2. However, alternative viral entry receptors and/or modulators of viral entry factors expression may contribute to infection in respiratory as well as non-respiratory tissues, including the kidneys and colon. Using single-cell analyses, we identified novel candidates for spike-mediated viral entry in epithelial cells from diverse fresh human tissues exposed to a labeled spike-pseudotyped virus. Systematic viral tracking revealed tissue-specific membrane receptors that contribute to viral entry, functionally validated in human tissues and partially predicted by molecular modeling. We found ADAM17 and IL1R1, together with canonical molecules, to significantly facilitate viral entry in the lung parenchyma, while entry into the renal cortex was less dependable on canonical factors, but strongly modulated by JAK1/2 engagement. These findings uncover distinct viral entry mechanisms across tissues and suggest novel organ-specific therapeutic targets for patients at risk.

microbiology↗

bioRxiv2025

Differential CD8+ T/NK cell-mediated reduction of HIV-1 replication after combination of ART with TIGIT or KLRG1 blockade in humanized mice

Expression of TIGIT and KLRG1 has been associated to an exhausted, dysfunctional state in natural killer (NK) and CD8+ T cells from people with HIV-1 (PWH), limiting the efficacy of immunotherapies aiming at achieving a functional cure of the infection. Antiretroviral therapy (ART) does not completely reverse this immune exhaustion, and its combination with blockade of immune checkpoint receptors such as TIGIT and KLRG1 could be a promising strategy to promote control of viral replication in PWH. However, the impact of targeting these two immune checkpoint receptors has not been evaluated in vivo. In this study, we used a humanized Bone Marrow, Liver and Thymus (hBLT) mouse model of HIV-1 infection to study the impact of ART in combination with aTIGIT or aKLRG1 or a bispecific aTIGIT/aKLRG1 mAbs. Our results indicated that combination of ART with either aTIGIT or aKLRG1 mAbs led to faster reduction of HIV-1 pVL. Furthermore, viral rebound after ART interruption (ATI) was delayed in mice treated with aTIGIT and aKLRG1 mAbs. Histological detection of HIV-1 p24 in the spleen was restricted to the white pulp in the aKLRG1 mAb-treated group, which correlated with higher infiltration of IFN{gamma}+ CD8+ T cells in these histological regions and with increased cytotoxic CD107a+ Granzyme B+ CD8+ T cells in the spleen. In contrast, control of HIV-1 replication induced by the aTIGIT mAb was associated with an increased splenic CD107a+ IFN{gamma}+ NKG2C+ CD57-adaptive NK cells. In contrast, combination of ART with a bispecific aTIGIT/aKLRG1 mAb was unable to efficiently suppress viral replication or delay viral rebound after ATI, potentially by inducing apoptosis of adaptive NKG2C+ NK. Together, these results suggest that combination of ART with individual TIGIT or KLRG1 blockade may be a promising immunotherapy strategy against HIV-1 by eliciting differential immune control mechanisms.

immunology↗

bioRxiv2025

Induction of Resident Memory CD8+T cell Phenotypes to Eliminate the HIV reservoir

During analytical treatment interruption (ATI), failure to contain tissue HIV reservoirs remains a major barrier to remission. We conditioned peripheral blood mononuclear cells with cues that promote tissue-resident memory differentiation, aiming to reprogram HIV-specific CD8+T cells for these tissue microenvironments. Sequential IL-15/TGF-{beta}1-stimulation expanded proliferative CD103+CD39+ effector populations and restored polyfunctional HIV-specific CD8+T cell responses, irrespective of CD39 or PD-1 expression. Cytokine-stimulated CD8+T cells enhanced ex vivo elimination of the HIV reservoir, and within the induced effector pool, only CD69+ subsets expressing CD103+ or CD39+ eliminated intact HIV-1 genomes. Single-cell transcriptomics showed that IL-15/TGF-{beta}1 stimulation increased clonotypic diversity and expanded resident-like effector clusters with reduced immune-checkpoint receptor expression and augmented mitochondrial function, findings confirmed by flow cytometry. Engrafted recipients from a humanized mouse ATI model more effectively eliminated HIV+-reactivated cells after adoptive transfer of sequentially-treated CD8+T cells. Thus, IL-15/TGF-{beta}1-mediated CD8+T cell reprogramming represents a promising immunotherapy to enable immune control after ATI.

immunology↗

bioRxiv2025

Early resident NK cell response to local HIV infection in lymphoid tissue

Natural killer (NK) cells are critical mediators of antiviral immunity, yet their role in lymphoid tissues--key reservoirs of HIV persistence--remains poorly defined. Here, we uncover a distinct cytotoxic signature of tonsil-resident NK cells essential for targeting HIV-infected CD4 T cells. Using a human tonsillar model of HIV infection and extracellular matrix-based functional assays, we identify a subset of NK cells co-expressing CD69, CD49a, CD103, and the adaptive marker NKG2C as potent effectors against autologous HIV-infected tissue CD4 T cells. Both CD16 and CD16- NK subsets exhibited cytotoxic antiviral activity. However, HIV infection induced profound functional alterations in these NK cells, including dysregulated expression of CD9, TRAF2, ITGA1, suggesting disrupted activation, signaling, and tissue residency. Functional assays corroborated a significant impairment in the cytotoxic capacity, indicating HIV-driven NK cell dysfunction. Intriguingly, a subset of immature CD16-CD69 NK cells underwent functional reprogramming, transitioning into a migration-competent, and metabolically primed state, driven by the upregulation of NUMAI, LCP1, SLC38A1, MT-ND2, NUMA1, MYH9, and CD44. Functional assays confirmed this transition, revealing changes in the expression of immune checkpoint receptors and a gain of cytotoxic function in these reprogrammed cells. These findings advance our understanding of NK cell biology in HIV infection and highlight novel avenues for NK-cell-based therapeutic strategies.

immunology↗

bioRxiv2024

Combined Dendritic Cell And Anti-TIGIT Immunotherapy Potentiate Trail+ Memory NK Cells Against HIV-1 Infected Cells

Natural Killer (NK) cells are promising tools for the development of immunotherapies targeting persistently infected CD4+ T cells to potentially achieve remission in people with HIV-1 (PWH). However, the chronicity of HIV-1 infection limits the functional properties of NK cells, and additional approaches are needed to potentiate their cytotoxic activity against HIV-1-infected cells. In the present study, we analyzed the reinvigoration of functional NK cells from PWH after priming with autologous dendritic cells (DC) stimulated with nanoparticles containing Poly I:C (Nano-PIC). We show that improved natural cytotoxic function in NK cell from PWH associates with increased proportions of NKG2C+CD57- precursors of memory NK, which eliminate HIV-1 infected CD4+ T cells mainly through the TRAIL receptor. In addition, expression of TIGIT but not TIM3 limited increase in NKG2C+ memory NK cell precursors and associated with persistent dysfunctionality of NK cells after stimulation with Nano PIC-DC. Blockade of TIGIT restored functional capacities of NK cell from PWH eliminating HIV-1 infected cells in vitro. Moreover, combining of NK cell and Nano-PIC-DC with anti-TIGIT mAbs immunotherapy limited the expansion of HIV-1 infected cells in humanized immunodeficient NSG mice transplanted with CD4+ T cells from PWH in vivo. Such viral control was associated with preserved NKG2C memory NK cell precursors, increased expression of granzyme B and TRAIL on NK in tissue from transplanted NSG mice. Together, combination of Nano-PIC DC and anti-TIGIT antibodies may be a promising strategy to increase the efficacy of immunotherapies aimed at HIV-1 cure. One sentence summaryStimulation of memory NK with a combination of DC and anti-TIGIT antibodies increase their ability to eliminate HIV-1 infected CD4+ T cells in vitro and in vivo.

immunology↗

bioRxiv2022

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.

immunology↗

bioRxiv2022

Zinc pyrithione is a potent inhibitor of PLPro and cathepsin L enzymes with ex vivo inhibition of SARS-CoV-2 entry and replication

As SARS-CoV-2 triggered a global health crisis, there is an urgent need to provide patients with safe, effective, accessible, and preferably oral therapeutics for COVID-19 that complement mRNA vaccines. Zinc compounds are widely known for their antiviral properties. Therefore, we have prepared a library of zinc complexes with pyrithione (1-hydroxy-2(1H)-pyridinethione) and its analogues, all of which showed promising in vitro inhibition of cathepsin L, an enzyme involved in SARS-CoV-2 entry, and PLPro, an enzyme involved in SARS-CoV-2 replication both in (sub)micromolar range. Zinc pyrithione 1a is a well-established, commercially available antimicrobial agent and was therefore selected for further evaluation of its SARS-CoV-2 entry and replication inhibition in an ex vivo system derived from primary human lung tissue. Our results suggest that zinc pyrithione complex 1a provides a multitarget approach to combat SARS-CoV-2 and should be considered for repurposing as a potential therapeutic against the insidious COVID-19 disease. Featured imageIn our study, we show that zinc pyrithione holds immense potential for the development of a possible out-patient treatment for SARS-CoV-2 due to its inhibition of viral entry and replication. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=167 SRC="FIGDIR/small/482819v1_ufig1.gif" ALT="Figure 1"> View larger version (111K): org.highwire.dtl.DTLVardef@2da94corg.highwire.dtl.DTLVardef@1c5da6borg.highwire.dtl.DTLVardef@86acd6org.highwire.dtl.DTLVardef@1bd4c3d_HPS_FORMAT_FIGEXP M_FIG C_FIG

biochemistry↗

bioRxiv2022

Identification of HIV-Reservoir Cells with Reduced Susceptibility to Antibody-Dependent Immune Response

HIV establishes a persistent infection in heterogeneous cell reservoirs, which can be maintained by different mechanisms including cellular proliferation, and represent the main obstacle to curing the infection. The expression of the Fc{gamma} receptor CD32 has been identified as a marker of the active cell reservoirs in people on antiretroviral therapy, but if its expression has any role in conferring advantage for viral persistence is unknown. Here, we report that HIV-infected cells expressing CD32 have reduced susceptibility to natural killer (NK) antibody-dependent cell cytotoxicity (ADCC) by a mechanism compatible with the suboptimal binding of HIV-specific antibodies. Infected CD32 cells have increased proliferative capacity in the presence of immune complexes, and are more resistant to strategies directed to potentiate NK function. Remarkably, reactivation of the latent reservoir from antiretroviral-treated people living with HIV increases the pool of infected CD32 cells, which are largely resistant to the ADCC immune mechanism. Thus, we report the existence of reservoir cells that evade part of the NK immune response through the expression of CD32. Graphical Abstract O_FIG_DISPLAY_L [Figure 1] M_FIG_DISPLAY C_FIG_DISPLAY

immunology↗

bioRxiv2021

Entrectinib - a SARS-CoV-2 inhibitor in Human Lung Tissue (HLT) cells

Since the start of the COVID-19 outbreak, pharmaceutical companies and research groups have focused on the development of vaccines and antiviral drugs against SARS-CoV-2. Here, we apply a drug repurposing strategy to identify potential drug candidates that are able to block the entrance of the virus into human cells. By combining virtual screening with in vitro pseudovirus assays and antiviral assays in Human Lung Tissue (HLT) cells, we identify entrectinib as a promising antiviral drug. We found that part of the antiviral action of entrectinib is mediated by a non-specific mechanism, likely occurring at the viral membrane level. Such a profile could provide entrectinib with protection against the development of drug resistance by emerging SARS-CoV-2 variants.

cell biology↗

bioRxiv2021

Novel Human Lung Tissue Model for the Study of SARS-CoV-2 Entry, Inflammation and New Therapeutics

The development of physiological models that reproduce SARS-CoV-2 infection in primary human cells will be instrumental to identify host-pathogen interactions and potential therapeutics. Here, using cell suspensions directly from primary human lung tissues (HLT), we have developed a rapid platform for the identification of viral targets and the expression of viral entry factors, as well as for the screening of viral entry inhibitors and anti-inflammatory compounds. The direct use of HLT cells, without long-term cell culture and in vitro differentiation approaches, preserves main immune and structural cell populations, including the most susceptible cell targets for SARS-CoV-2; alveolar type II (AT-II) cells, while maintaining the expression of proteins involved in viral infection, such as ACE2, TMPRSS2, CD147 and AXL. Further, antiviral testing of 39 drug candidates reveals a highly reproducible method, suitable for different SARS-CoV-2 variants, and provides the identification of new compounds missed by conventional systems, such as VeroE6. Using this method, we also show that interferons do not modulate ACE2 expression, and that stimulation of local inflammatory responses can be modulated by different compounds with antiviral activity. Overall, we present a relevant and rapid method for the study of SARS-CoV-2. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=193 SRC="FIGDIR/small/440731v2_ufig1.gif" ALT="Figure 1"> View larger version (48K): org.highwire.dtl.DTLVardef@96abf6org.highwire.dtl.DTLVardef@1f3cfe3org.highwire.dtl.DTLVardef@1d55fdborg.highwire.dtl.DTLVardef@1884cd6_HPS_FORMAT_FIGEXP M_FIG C_FIG HighlightsEx vivo physiological systems for the study of SARS-CoV-2-host interactions are scarce. Here, we establish a method using primary human lung tissue (HLT) cells for the rapid analysis of cell tropism and identification of therapeutics. O_LIHLT cells preserve main cell subpopulations, including alveolar type-2 cells, and expression of SARS-CoV-2 entry factors ACE2, CD147, TMPRSS2 and AXL. C_LIO_LIHLT cells are readily susceptible to SARS-CoV-2 infection without the need of cell isolation or further cell differentiation. C_LIO_LIAntiviral testing in HLT cells allows the rapid identification of new drug candidates against SARS-CoV-2 variants, missed by conventional systems. C_LIO_LILocal inflammation is supported in HLT cells and offers the identification of relevant anti-inflammatory compounds for SARS-CoV-2 infection. C_LI

microbiology↗