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

SARS-CoV-2; Inhibition; ZincSARS-CoV-2; Inhibició; ZincSARS-CoV-2; Inhibición; ZincZinc pyrithione (1a), together with its analogues 1b–h and ruthenium pyrithione complex 2a, were synthesised and evaluated for the stability in biologically relevant media and anti-SARS-CoV-2 activity. Zinc pyrithione revealed potent in vitro inhibition of cathepsin L (IC50=1.88 ± 0.49 µM) and PLPro (IC50=0.50 ± 0.07 µM), enzymes involved in SARS-CoV-2 entry and replication, respectively, as well as antiviral entry and replication properties in an ex vivo system derived from primary human lung tissue. Zinc complexes 1b–h expressed comparable in vitro inhibition. On the contrary, ruthenium complex 2a and the ligand pyrithione a itself expressed poor inhibition in mentioned assays, indicating the importance of the selection of metal core and structure of metal complex for antiviral activity. Safe, effective, and preferably oral at-home therapeutics for COVID-19 are needed and as such zinc pyrithione, which is also commercially available, could be considered as a potential therapeutic agent against SARS-CoV-2.The authors acknowledge the financial support from the Slovenian Research Agency ARRS [Research Core Funding No. P1-0175 together with an increase in research programme funding related to the COVID-19 pandemic], and the grant from the Health Department of the Government of Catalonia [DGRIS 1_5] and the Fundació La Marató TV3 [Grants 202104FMTV3 and 202112FMTV3] to M.G. and MJ.B. MJ.B is supported by the Miguel Servet Program funded by the Spanish Health Institute Carlos III [CP17/00179]

Entrectinib—A SARS-CoV-2 Inhibitor in Human Lung Tissue (HLT) Cells

COVID-19; Drug repurposing; Viral cell entry assaysCOVID-19; Reutilización de medicamentos; Ensayos de entrada de células viralesCOVID-19; Reutilització de medicaments; Assajos d'entrada de cèl·lules viralsSince 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 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 potential antiviral drug.This research was funded by the Spanish Ministry of Science, Innovation, and Universities (FPU16/01209 to M.T.-F.); the Health department of the Government of Catalonia (DGRIS 3_9 to A.P.G. and J.S. and DGRIS 1_5 to M.J.B. and M.G.)

Dendritic Cells From the Cervical Mucosa Capture and Transfer HIV-1 via Siglec-1

HIV-1; Siglec-1; CervixVIH-1; Siglec-1; CèrvixVIH-1; Siglec-1; CérvixAntigen presenting cells from the cervical mucosa are thought to amplify incoming HIV-1 and spread infection systemically without being productively infected. Yet, the molecular mechanism at the cervical mucosa underlying this viral transmission pathway remains unknown. Here we identified a subset of HLA-DR+ CD14+ CD11c+ cervical DCs at the lamina propria of the ectocervix and the endocervix that expressed the type-I interferon inducible lectin Siglec-1 (CD169), which promoted viral uptake. In the cervical biopsy of a viremic HIV-1+ patient, Siglec-1+ cells harbored HIV-1-containing compartments, demonstrating that in vivo, these cells trap viruses. Ex vivo, a type-I interferon antiviral environment enhanced viral capture and trans-infection via Siglec-1. Nonetheless, HIV-1 transfer via cervical DCs was effectively prevented with antibodies against Siglec-1. Our findings contribute to decipher how cervical DCs may boost HIV-1 replication and promote systemic viral spread from the cervical mucosa, and highlight the importance of including inhibitors against Siglec-1 in microbicidal strategies

Latency reversal agents affect differently the latent reservoir present in distinct CD4+ T subpopulations

CD4+ T cell; HIV-1; Latent reservoirCélula T CD4 +; VIH-1; Reservorio latenteCèl·lula T CD4 +; VIH-1; Reservori latentLatency reversal agents (LRAs) have proven to induce HIV-1 transcription in vivo but are ineffective at decreasing the size of the latent reservoir in antiretroviral treated patients. The capacity of the LRAs to perturb the viral reservoir present in distinct subpopulations of cells is currently unknown. Here, using a new RNA FISH/flow ex vivo viral reactivation assay, we performed a comprehensive assessment of the viral reactivation capacity of different families of LRAs, and their combinations, in different CD4+ T cell subsets. We observed that a median of 16.28% of the whole HIV-reservoir induced HIV-1 transcripts after viral reactivation, but only 10.10% of these HIV-1 RNA+ cells produced the viral protein p24. Moreover, none of the LRAs were powerful enough to reactivate HIV-1 transcription in all CD4+ T cell subpopulations. For instance, the combination of Romidepsin and Ingenol was identified as the best combination of drugs at increasing the proportion of HIV-1 RNA+ cells, in most, but not all, CD4+ T cell subsets. Importantly, memory stem cells were identified as highly resistant to HIV-1 reactivation, and only the combination of Panobinostat and Bryostatin-1 significantly increased the number of cells transcribing HIV within this subset. Overall, our results validate the use of the RNA FISH/flow technique to assess the potency of LRAs among different CD4+ T cell subsets, manifest the intrinsic differences between cells that encompass the latent HIV reservoir, and highlight the difficulty to significantly impact the latent infection with the currently available drugs. Thus, our results have important implications for the rational design of therapies aimed at reversing HIV latency from diverse cellular reservoirs.This study was supported by the American National Institutes of Health (grant R21AI118411 to MJB), the Spanish Secretariat of Science and Innovation and FEDER funds (grant SAF2015-67334-R [MINECO/FEDER]), a unrestricted research grant from Bristol-Myers Squibb S.A.U (PfC-2015 AI424-564) to MJB, the Spanish "Ministerio de Economia y Competitividad, Instituto de Salud Carlos III"(ISCIII, PI17/01470) to M.G, a research grant from Gilead Sciences (GLD17-00204) to M. B, GeSIDA and the Spanish AIDS network "Red Tematica Cooperativa de Investigacion en SIDA" (RD16/0025/0007) to ER. The Miguel Servet program funded by the Spanish Health Institute Carlos III (CP17/00179) to MJB. The "Pla estrategic de recerca i innovacioen salut" (PERIS), from the Catalan Government to MG

Expression of CD20 after viral reactivation renders HIV-reservoir cells susceptible to Rituximab

Rituximab; Viral reactivation; CD20Rituximab; Reactivació viral; CD20Rituximab; Reactivación viral; CD20The identification of exclusive markers to target HIV-reservoir cells will represent a significant advance in the search for therapies to cure HIV. Here, we identify the B lymphocyte antigen CD20 as a marker for HIV-infected cells in vitro and in vivo. The CD20 molecule is dimly expressed in a subpopulation of CD4-positive (CD4+) T lymphocytes from blood, with high levels of cell activation and heterogeneous memory phenotypes. In lymph node samples from infected patients, CD20 is present in productively HIV-infected cells, and ex vivo viral infection selectively upregulates the expression of CD20 during early infection. In samples from patients on antiretroviral therapy (ART) this subpopulation is significantly enriched in HIV transcripts, and the anti-CD20 monoclonal antibody Rituximab induces cell killing, which reduces the pool of HIV-expressing cells when combined with latency reversal agents. We provide a tool for targeting this active HIV-reservoir after viral reactivation in patients while on ART.This study was supported by the American National Institutes of Health (grant R21AI118411 to M.B.), the Spanish Secretariat of Science and Innovation and FEDER funds (grant SAF2015-67334-R [MINECO/FEDER]), the Spanish "Ministerio de Economia y Competitividad, Instituto de Salud Carlos III" (ISCIII, PI17/01470), GeSIDA and the Spanish AIDS network Red Tematica Cooperativa de Investigacion en SIDA (RD16/0025/0007). M.B. is supported by the Miguel Servet program funded by the Spanish Health Institute Carlos III (CP17/00179). M.G. is supported by the "Pla estrategic de recerca i innovacio en salut" (PERIS), from the Catalan Government