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1.
Cell Rep ; 42(3): 112189, 2023 03 28.
Article in English | MEDLINE | ID: covidwho-2240749

ABSTRACT

Cognitive dysfunction is often reported in patients with post-coronavirus disease 2019 (COVID-19) syndrome, but its underlying mechanisms are not completely understood. Evidence suggests that severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Spike protein or its fragments are released from cells during infection, reaching different tissues, including the CNS, irrespective of the presence of the viral RNA. Here, we demonstrate that brain infusion of Spike protein in mice has a late impact on cognitive function, recapitulating post-COVID-19 syndrome. We also show that neuroinflammation and hippocampal microgliosis mediate Spike-induced memory dysfunction via complement-dependent engulfment of synapses. Genetic or pharmacological blockage of Toll-like receptor 4 (TLR4) signaling protects animals against synapse elimination and memory dysfunction induced by Spike brain infusion. Accordingly, in a cohort of 86 patients who recovered from mild COVID-19, the genotype GG TLR4-2604G>A (rs10759931) is associated with poor cognitive outcome. These results identify TLR4 as a key target to investigate the long-term cognitive dysfunction after COVID-19 infection in humans and rodents.


Subject(s)
COVID-19 , Cognitive Dysfunction , Humans , Animals , Mice , COVID-19/complications , Spike Glycoprotein, Coronavirus/genetics , SARS-CoV-2/metabolism , Toll-Like Receptor 4 , Post-Acute COVID-19 Syndrome
2.
J Clin Virol Plus ; 2(4): 100121, 2022 Nov.
Article in English | MEDLINE | ID: covidwho-2210737

ABSTRACT

Background: Vaccination against COVID-19 was implemented very quickly, but the emergence of new variants that can evade the previous acquired immunological protection highlights the importance of understanding the mechanisms involved in the immune response generated after SARS-CoV-2 infection or vaccination. Objectives: Since most of our knowledge on the humoral immunity generated against SARS-CoV-2 has been obtained from studies with infected patients before vaccination, our goal here was to evaluate seroconversion and its correlation with the titers of neutralizing antibodies (NAbs) in individuals who received the complete initial recommended vaccination schedule with three different vaccines. Study design: We analyzed serum IgG, IgA and total NAbs against the trimeric SARS-CoV-2 Spike (S) protein or its receptor binding domain (RBD) in blood samples collected from 118 healthy individuals without known previous infection, before and after receiving the first and the second dose of CoronaVac (n = 18), ChAdOx-1 (n = 68) or BNT162b2 (n = 32) vaccines. Results: We found that although IgG titers were high in all sera collected after the two doses of these vaccines, NAbs amounts varies among the groups. In contrast, serum NAbs concentrations were much more comparable to the IgA levels, indicating that these antibodies would have a major neutralizing capacity against SARS-CoV-2. Conclusions: Altogether our data suggest that quantification of serum anti-S or anti-RBD IgA, rather than IgG, may be a valuable tool to screen NAbs and may be considered for surveillance of vaccine coverage.

3.
Berg, Hannes, Wirtz Martin, Maria A.; Altincekic, Nadide, Islam, Alshamleh, Bains, Jasleen Kaur, Blechar, Julius, Ceylan, Betül, de Jesus, Vanessa, Karthikeyan, Dhamotharan, Fuks, Christin, Gande, Santosh L.; Hargittay, Bruno, Hohmann, Katharina F.; Hutchison, Marie T.; Korn, Sophie Marianne, Krishnathas, Robin, Kutz, Felicitas, Linhard, Verena, Matzel, Tobias, Meiser, Nathalie, Niesteruk, Anna, Pyper, Dennis J.; Schulte, Linda, Trucks, Sven, Azzaoui, Kamal, Blommers, Marcel J. J.; Gadiya, Yojana, Karki, Reagon, Zaliani, Andrea, Gribbon, Philip, Marcius da Silva, Almeida, Cristiane Dinis, Anobom, Bula, Anna L.; Bütikofer, Matthias, Caruso, Ícaro Putinhon, Felli, Isabella Caterina, Da Poian, Andrea T.; Gisele Cardoso de, Amorim, Fourkiotis, Nikolaos K.; Gallo, Angelo, Ghosh, Dhiman, Francisco, Gomes‐Neto, Gorbatyuk, Oksana, Hao, Bing, Kurauskas, Vilius, Lecoq, Lauriane, Li, Yunfeng, Nathane Cunha, Mebus‐Antunes, Mompeán, Miguel, Thais Cristtina, Neves‐Martins, Martí, Ninot‐Pedrosa, Pinheiro, Anderson S.; Pontoriero, Letizia, Pustovalova, Yulia, Riek, Roland, Robertson, Angus J.; Abi Saad, Marie Jose, Treviño, Miguel Á, Tsika, Aikaterini C.; Almeida, Fabio C. L.; Bax, Ad, Katherine, Henzler‐Wildman, Hoch, Jeffrey C.; Jaudzems, Kristaps, Laurents, Douglas V.; Orts, Julien, Pierattelli, Roberta, Spyroulias, Georgios A.; Elke, Duchardt‐Ferner, Ferner, Jan, Fürtig, Boris, Hengesbach, Martin, Löhr, Frank, Qureshi, Nusrat, Richter, Christian, Saxena, Krishna, Schlundt, Andreas, Sreeramulu, Sridhar, Wacker, Anna, Weigand, Julia E.; Julia, Wirmer‐Bartoschek, Wöhnert, Jens, Schwalbe, Harald.
Angewandte Chemie ; 134(46), 2022.
Article in English | ProQuest Central | ID: covidwho-2103465

ABSTRACT

SARS‐CoV‐2 (SCoV2) and its variants of concern pose serious challenges to the public health. The variants increased challenges to vaccines, thus necessitating for development of new intervention strategies including anti‐virals. Within the international Covid19‐NMR consortium, we have identified binders targeting the RNA genome of SCoV2. We established protocols for the production and NMR characterization of more than 80 % of all SCoV2 proteins. Here, we performed an NMR screening using a fragment library for binding to 25 SCoV2 proteins and identified hits also against previously unexplored SCoV2 proteins. Computational mapping was used to predict binding sites and identify functional moieties (chemotypes) of the ligands occupying these pockets. Striking consensus was observed between NMR‐detected binding sites of the main protease and the computational procedure. Our investigation provides novel structural and chemical space for structure‐based drug design against the SCoV2 proteome.

4.
Angew Chem Int Ed Engl ; 61(46): e202205858, 2022 Nov 14.
Article in English | MEDLINE | ID: covidwho-2034712

ABSTRACT

SARS-CoV-2 (SCoV2) and its variants of concern pose serious challenges to the public health. The variants increased challenges to vaccines, thus necessitating for development of new intervention strategies including anti-virals. Within the international Covid19-NMR consortium, we have identified binders targeting the RNA genome of SCoV2. We established protocols for the production and NMR characterization of more than 80 % of all SCoV2 proteins. Here, we performed an NMR screening using a fragment library for binding to 25 SCoV2 proteins and identified hits also against previously unexplored SCoV2 proteins. Computational mapping was used to predict binding sites and identify functional moieties (chemotypes) of the ligands occupying these pockets. Striking consensus was observed between NMR-detected binding sites of the main protease and the computational procedure. Our investigation provides novel structural and chemical space for structure-based drug design against the SCoV2 proteome.


Subject(s)
COVID-19 Drug Treatment , SARS-CoV-2 , Humans , Proteome , Ligands , Drug Design
5.
Sci Rep ; 12(1): 10366, 2022 06 20.
Article in English | MEDLINE | ID: covidwho-1900657

ABSTRACT

The Covid-19 pandemic, caused by SARS-CoV-2, has resulted in over 6 million reported deaths worldwide being one of the biggest challenges the world faces today. Here we present optimizations of all steps of an enzyme-linked immunosorbent assay (ELISA)-based test to detect IgG, IgA and IgM against the trimeric spike (S) protein, receptor binding domain (RBD), and N terminal domain of the nucleocapsid (N-NTD) protein of SARS-CoV-2. We discuss how to determine specific thresholds for antibody positivity and its limitations according to the antigen used. We applied the assay to a cohort of 126 individuals from Rio de Janeiro, Brazil, consisting of 23 PCR-positive individuals and 103 individuals without a confirmed diagnosis for SARS-CoV-2 infection. To illustrate the differences in serological responses to vaccinal immunization, we applied the test in 18 individuals from our cohort before and after receiving ChAdOx-1 nCoV-19 or CoronaVac vaccines. Taken together, our results show that the test can be customized at different stages depending on its application, enabling the user to analyze different cohorts, saving time, reagents, or samples. It is also a valuable tool for elucidating the immunological consequences of new viral strains and monitoring vaccination coverage and duration of response to different immunization regimens.


Subject(s)
COVID-19 , Seroconversion , Antibodies, Viral/analysis , Brazil , COVID-19/diagnosis , COVID-19/prevention & control , COVID-19 Vaccines/administration & dosage , ChAdOx1 nCoV-19/administration & dosage , Coronavirus Nucleocapsid Proteins/immunology , Humans , Immunoglobulin A , Immunoglobulin G , Immunoglobulin M , Pandemics , Phosphoproteins/immunology , SARS-CoV-2 , Spike Glycoprotein, Coronavirus/immunology , Vaccination , Vaccines, Inactivated/administration & dosage
6.
Pharmaceutics ; 14(4)2022 Mar 29.
Article in English | MEDLINE | ID: covidwho-1798886

ABSTRACT

Viral disease outbreaks affect hundreds of millions of people worldwide and remain a serious threat to global health. The current SARS-CoV-2 pandemic and other recent geographically- confined viral outbreaks (severe acute respiratory syndrome (SARS), Ebola, dengue, zika and ever-recurring seasonal influenza), also with devastating tolls at sanitary and socio-economic levels, are sobering reminders in this respect. Among the respective pathogenic agents, Zika virus (ZIKV), transmitted by Aedes mosquito vectors and causing the eponymous fever, is particularly insidious in that infection during pregnancy results in complications such as foetal loss, preterm birth or irreversible brain abnormalities, including microcephaly. So far, there is no effective remedy for ZIKV infection, mainly due to the limited ability of antiviral drugs to cross blood-placental and/or blood-brain barriers (BPB and BBB, respectively). Despite its restricted permeability, the BBB is penetrable by a variety of molecules, mainly peptide-based, and named BBB peptide shuttles (BBBpS), able to ferry various payloads (e.g., drugs, antibodies, etc.) into the brain. Recently, we have described peptide-porphyrin conjugates (PPCs) as successful BBBpS-associated drug leads for HIV, an enveloped virus in which group ZIKV also belongs. Herein, we report on several brain-directed, low-toxicity PPCs capable of targeting ZIKV. One of the conjugates, PP-P1, crossing both BPB and BBB, has shown to be effective against ZIKV (IC50 1.08 µM) and has high serum stability (t1/2 ca. 22 h) without altering cell viability at all tested concentrations. Peptide-porphyrin conjugation stands out as a promising strategy to fill the ZIKV treatment gap.

7.
Pharmaceutics ; 14(4):738, 2022.
Article in English | MDPI | ID: covidwho-1762681

ABSTRACT

Viral disease outbreaks affect hundreds of millions of people worldwide and remain a serious threat to global health. The current SARS-CoV-2 pandemic and other recent geographically- confined viral outbreaks (severe acute respiratory syndrome (SARS), Ebola, dengue, zika and ever-recurring seasonal influenza), also with devastating tolls at sanitary and socio-economic levels, are sobering reminders in this respect. Among the respective pathogenic agents, Zika virus (ZIKV), transmitted by Aedes mosquito vectors and causing the eponymous fever, is particularly insidious in that infection during pregnancy results in complications such as foetal loss, preterm birth or irreversible brain abnormalities, including microcephaly. So far, there is no effective remedy for ZIKV infection, mainly due to the limited ability of antiviral drugs to cross blood–placental and/or blood–brain barriers (BPB and BBB, respectively). Despite its restricted permeability, the BBB is penetrable by a variety of molecules, mainly peptide-based, and named BBB peptide shuttles (BBBpS), able to ferry various payloads (e.g., drugs, antibodies, etc.) into the brain. Recently, we have described peptide–porphyrin conjugates (PPCs) as successful BBBpS-associated drug leads for HIV, an enveloped virus in which group ZIKV also belongs. Herein, we report on several brain-directed, low-toxicity PPCs capable of targeting ZIKV. One of the conjugates, PP-P1, crossing both BPB and BBB, has shown to be effective against ZIKV (IC50 1.08 µM) and has high serum stability (t1/2 ca. 22 h) without altering cell viability at all tested concentrations. Peptide–porphyrin conjugation stands out as a promising strategy to fill the ZIKV treatment gap.

8.
Int J Biol Macromol ; 203: 466-480, 2022 Apr 01.
Article in English | MEDLINE | ID: covidwho-1630871

ABSTRACT

The SARS-CoV-2 nucleocapsid protein (N) is a multifunctional promiscuous nucleic acid-binding protein, which plays a major role in nucleocapsid assembly and discontinuous RNA transcription, facilitating the template switch of transcriptional regulatory sequences (TRS). Here, we dissect the structural features of the N protein N-terminal domain (N-NTD) and N-NTD plus the SR-rich motif (N-NTD-SR) upon binding to single and double-stranded TRS DNA, as well as their activities for dsTRS melting and TRS-induced liquid-liquid phase separation (LLPS). Our study gives insights on the specificity for N-NTD(-SR) interaction with TRS. We observed an approximation of the triple-thymidine (TTT) motif of the TRS to ß-sheet II, giving rise to an orientation difference of ~25° between dsTRS and non-specific sequence (dsNS). It led to a local unfavorable energetic contribution that might trigger the melting activity. The thermodynamic parameters of binding of ssTRSs and dsTRS suggested that the duplex dissociation of the dsTRS in the binding cleft is entropically favorable. We showed a preference for TRS in the formation of liquid condensates when compared to NS. Moreover, our results on DNA binding may serve as a starting point for the design of inhibitors, including aptamers, against N, a possible therapeutic target essential for the virus infectivity.


Subject(s)
COVID-19/virology , Nucleic Acids/metabolism , Nucleocapsid Proteins/metabolism , Protein Interaction Domains and Motifs , SARS-CoV-2/physiology , Binding Sites , DNA/chemistry , DNA/metabolism , Gene Expression Regulation, Viral , Host-Pathogen Interactions , Humans , Hydrogen Bonding , Models, Molecular , Nucleic Acids/chemistry , Nucleocapsid Proteins/chemistry , Protein Binding , RNA/chemistry , RNA/metabolism , Spectrum Analysis , Structure-Activity Relationship
9.
Biophys J ; 120(14): 2814-2827, 2021 07 20.
Article in English | MEDLINE | ID: covidwho-1604124

ABSTRACT

The nucleocapsid (N) protein of betacoronaviruses is responsible for nucleocapsid assembly and other essential regulatory functions. The N protein N-terminal domain (N-NTD) interacts and melts the double-stranded transcriptional regulatory sequences (dsTRSs), regulating the discontinuous subgenome transcription process. Here, we used molecular dynamics (MD) simulations to study the binding of the severe acute respiratory syndrome coronavirus 2 N-NTD to nonspecific (NS) and TRS dsRNAs. We probed dsRNAs' Watson-Crick basepairing over 25 replicas of 100 ns MD simulations, showing that only one N-NTD of dimeric N is enough to destabilize dsRNAs, triggering melting initiation. dsRNA destabilization driven by N-NTD was more efficient for dsTRSs than dsNS. N-NTD dynamics, especially a tweezer-like motion of ß2-ß3 and Δ2-ß5 loops, seems to play a key role in Watson-Crick basepairing destabilization. Based on experimental information available in the literature, we constructed kinetics models for N-NTD-mediated dsRNA melting. Our results support a 1:1 stoichiometry (N-NTD/dsRNA), matching MD simulations and raising different possibilities for N-NTD action: 1) two N-NTD arms of dimeric N would bind to two different RNA sites, either closely or spatially spaced in the viral genome, in a cooperative manner; and 2) monomeric N-NTD would be active, opening up the possibility of a regulatory dissociation event.


Subject(s)
COVID-19 , SARS-CoV-2 , Humans , Nucleocapsid Proteins/genetics , Nucleoproteins , RNA
10.
Neuropharmacology ; 201: 108841, 2021 12 15.
Article in English | MEDLINE | ID: covidwho-1466809

ABSTRACT

A strong association between perinatal viral infections and neurodevelopmental disorders has been established. Both the direct contact of the virus with the developing brain and the strong maternal immune response originated by viral infections can impair proper neurodevelopment. Coronavirus disease 2019 (COVID-19), caused by the highly-infectious severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is currently responsible for a large global outbreak and is a major public health issue. While initial studies focused on the viral impact on the respiratory system, increasing evidence suggest that SARS-CoV-2 infects other organs and tissues including the mature brain. While studies continue to determine the neuropathology associated to COVID-19, the consequences of SARS-CoV-2 infection to the developing brain remain largely unexplored. The present review discusses evidence suggesting that SARS-CoV-2 infection may have persistent effects on the course of pregnancy and on brain development. Studies have shown that several proinflammatory mediators which are increased in the SARS-CoV-2-associated cytokine storm, are also modified in other viral infections known to increase the risk of neurodevelopmental disorders. In this sense, further studies should assess the genuine effects of SARS-CoV-2 infection during pregnancy and delivery along with an extended follow-up of the offspring, including neurocognitive, neuroimaging, and electrophysiological examination. It also remains to be determined whether and by which mechanisms SARS-CoV-2 intrauterine and early life infection could lead to an increased risk of developing neuropsychiatric disorders, such as autism (ASD) and schizophrenia (SZ), in the offspring.


Subject(s)
Autism Spectrum Disorder/epidemiology , COVID-19/epidemiology , Cytokine Release Syndrome/epidemiology , Neurodevelopmental Disorders/epidemiology , Pregnancy Complications, Infectious/epidemiology , Prenatal Exposure Delayed Effects/epidemiology , Schizophrenia/epidemiology , Autism Spectrum Disorder/immunology , Brain/embryology , Brain/immunology , COVID-19/immunology , Cytokine Release Syndrome/immunology , Female , Humans , Infectious Disease Transmission, Vertical , Neurodevelopmental Disorders/immunology , Pregnancy , Pregnancy Complications, Infectious/immunology , Prenatal Exposure Delayed Effects/immunology , Risk Factors , SARS-CoV-2 , Schizophrenia/immunology
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