Pereira B, Amaral AL, Dias A, Mendes N, Muncan V, Silva AR, Thibert C, Radu AG, David L, M�ximo V, van den Brink GR, Billaud M, Almeida R
PMID: 32052574 | DOI: 10.15252/embr.201948938
Intestinal stem cells (ISCs) fuel the lifelong self-renewal of the intestinal tract and are paramount for epithelial repair. In this context, the Wnt pathway component LGR5 is the most consensual ISC marker to date. Still, the effort to better understand ISC identity and regulation remains a challenge. We have generated a Mex3a knockout mouse model and show that this RNA-binding protein is crucial for the maintenance of the Lgr5+ ISC pool, as its absence disrupts epithelial turnover during postnatal development and stereotypical organoid maturation ex vivo. Transcriptomic profiling of intestinal crypts reveals that Mex3a deletion induces the peroxisome proliferator-activated receptor (PPAR) pathway, along with a decrease in Wnt signalling and loss of the Lgr5+ stem cell signature. Furthermore, we identify PPAR? activity as a molecular intermediate of MEX3A-mediated regulation. We also show that high PPAR? signalling impairs Lgr5+ ISC function, thus uncovering a new layer of post-transcriptional regulation that critically contributes to intestinal homeostasis
Mucker, EM;Brocato, RL;Principe, LM;Kim, RK;Zeng, X;Smith, JM;Kwilas, SA;Kim, S;Horton, H;Caproni, L;Hooper, JW;
PMID: 35891268 | DOI: 10.3390/vaccines10071104
To combat the COVID-19 pandemic, an assortment of vaccines has been developed. Nucleic acid vaccines have the advantage of rapid production, as they only require a viral antigen sequence and can readily be modified to detected viral mutations. Doggybone DNA vaccines targeting the spike protein of SARS-CoV-2 have been generated and compared with a traditionally manufactured, bacterially derived plasmid DNA vaccine that utilizes the same spike sequence. Administered to Syrian hamsters by jet injection at two dose levels, the immunogenicity of both DNA vaccines was compared following two vaccinations. Immunized hamsters were then immunosuppressed and exposed to SARS-CoV-2. Significant differences in body weight were observed during acute infection, and lungs collected at the time of euthanasia had significantly reduced viral RNA, infectious virus, and pathology compared with irrelevant DNA-vaccinated controls. Moreover, immune serum from vaccinated animals was capable of neutralizing SARS-CoV-2 variants of interest and importance in vitro. These data demonstrate the efficacy of a synthetic DNA vaccine approach to protect hamsters from SARS-CoV-2.
Chen, DY;Turcinovic, J;Feng, S;Kenney, DJ;Chin, CV;Choudhary, MC;Conway, HL;Semaan, M;Close, BJ;Tavares, AH;Seitz, S;Khan, N;Kapell, S;Crossland, NA;Li, JZ;Douam, F;Baker, SC;Connor, JH;Saeed, M;
PMID: 37095858 | DOI: 10.1016/j.isci.2023.106634
A simple and robust cell culture system is essential for generating authentic SARS-CoV-2 stocks for evaluation of viral pathogenicity, screening of antiviral compounds, and preparation of inactivated vaccines. Evidence suggests that Vero E6, a cell line commonly used in the field to grow SARS-CoV-2, does not support efficient propagation of new viral variants and triggers rapid cell culture adaptation of the virus. We generated a panel of 17 human cell lines overexpressing SARS-CoV-2 entry factors and tested their ability to support viral infection. Two cell lines, Caco-2/AT and HuH-6/AT, demonstrated exceptional susceptibility, yielding highly concentrated virus stocks. Notably, these cell lines were more sensitive than Vero E6 cells in recovering SARS-CoV-2 from clinical specimens. Further, Caco-2/AT cells provided a robust platform for producing genetically reliable recombinant SARS-CoV-2 through a reverse genetics system. These cellular models are a valuable tool for the study of SARS-CoV-2 and its continuously emerging variants.
Berry, N;Ferguson, D;Kempster, S;Hall, J;Ham, C;Jenkins, A;Rannow, V;Giles, E;Leahy, R;Goulding, S;Fernandez, A;Adedeji, Y;Vessillier, S;Rajagopal, D;Prior, S;Le Duff, Y;Hurley, M;Gilbert, S;Fritzsche, M;Mate, R;Rose, N;Francis, RJ;MacLellan-Gibson, K;Suarez-Bonnet, A;Priestnall, S;Almond, N;
PMID: 36333445 | DOI: 10.1038/s41598-022-23339-x
SARS-CoV-2 exhibits a diverse host species range with variable outcomes, enabling differential host susceptibility studies to assess suitability for pre-clinical countermeasure and pathogenesis studies. Baseline virological, molecular and pathological outcomes were determined among multiple species-one Old World non-human primate (NHP) species (cynomolgus macaques), two New World NHP species (red-bellied tamarins; common marmosets) and Syrian hamsters-following single-dose, atraumatic intranasal administration of SARS-CoV-2/Victoria-01. After serial sacrifice 2, 10 and 28-days post-infection (dpi), hamsters and cynomolgus macaques displayed differential virus biodistribution across respiratory, gastrointestinal and cardiovascular systems. Uniquely, New World tamarins, unlike marmosets, exhibited high levels of acute upper airway infection, infectious virus recovery associated with mild lung pathology representing a host previously unrecognized as susceptible to SARS-CoV-2. Across all species, lung pathology was identified post-clearance of virus shedding (antigen/RNA), with an association of virus particles within replication organelles in lung sections analysed by electron microscopy. Disrupted cell ultrastructure and lung architecture, including abnormal morphology of mitochondria 10-28 dpi, represented on-going pathophysiological consequences of SARS-CoV-2 in predominantly asymptomatic hosts. Infection kinetics and host pathology comparators using standardized methodologies enables model selection to bridge differential outcomes within upper and lower respiratory tracts and elucidate longer-term consequences of asymptomatic SARS-CoV-2 infection.
Kaufmann, E;Khan, N;Tran, KA;Ulndreaj, A;Pernet, E;Fontes, G;Lupien, A;Desmeules, P;McIntosh, F;Abow, A;Moorlag, SJCFM;Debisarun, P;Mossman, K;Banerjee, A;Karo-Atar, D;Sadeghi, M;Mubareka, S;Vinh, DC;King, IL;Robbins, CS;Behr, MA;Netea, MG;Joubert, P;Divangahi, M;
PMID: 35235831 | DOI: 10.1016/j.celrep.2022.110502
Since the vast majority of species solely rely on innate immunity for host defense, it stands to reason that a critical evolutionary trait like immunological memory evolved in this primitive branch of our immune system. There is ample evidence that vaccines such as bacillus Calmette-Guérin (BCG) induce protective innate immune memory responses (trained immunity) against heterologous pathogens. Here we show that while BCG vaccination significantly reduces morbidity and mortality against influenza A virus (IAV), it fails to provide protection against severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). In contrast to IAV, SARS-CoV-2 infection leads to unique pulmonary vasculature damage facilitating viral dissemination to other organs, including the bone marrow (BM), a central site for BCG-mediated trained immunity. Finally, monocytes from BCG-vaccinated individuals mount an efficient cytokine response to IAV infection, while this response is minimal following SARS-CoV-2. Collectively, our data suggest that the protective capacity of BCG vaccination is contingent on viral pathogenesis and tissue tropism.
Society on NeuroImmune Pharmacology COVID-19 Virtual Workshop
Journal of neuroimmune pharmacology : the official journal of the Society on NeuroImmune Pharmacology
Kumar, S;Pendyala, G;Yelamanchili, SV;Seth, P;Maggirwar, S;Bidlack, JM;Chang, SL;
PMID: 34181181 | DOI: 10.1007/s11481-021-10001-y
This brief report collects the program and abstracts of the Society on NeuroImmune Pharmacology (SNIP) COVID-19 Virtual Workshop held on April 9, 2021. The workshop consisted of four symposia: Symposium 1: Molecular approaches to COVID-19 pathogenesis and underlying mechanisms; Symposium 2: Therapeutic and vaccine approaches to COVID-19; Symposium 3: Early Career Investigator talks; and Symposium 4: Diversity and Inclusion SNIP Committee (DISC) program: Well-being and reflections. The workshop also featured four special talks on COVID-19 and funding opportunities from the National Institute on Alcohol Abuse and Alcoholism (NIAAA); COVID-19 and funding opportunities from the National Institute on Drug Abuse (NIDA); opportunities from NIH for early career investigator (ECI) fellows; and neurologic and psychiatric complications of SARS-CoV-2 infection. Presenters included NIH officials, SNIP members, and non-member scientists whose abstracts were submitted and accepted for inclusion in the virtual event hosted by the University of Nebraska Medical Center via Zoom webinar. A special theme issue of SNIP's official journal, the Journal of Neuroimmune Pharmacology (JNIP), will collect select papers from the workshop along with other related manuscripts in a special theme issue titled "Neuroimmune Pharmacology of SARS-CoV-2."
Molecular Analysis of the Kidney From a Patient With COVID-19-Associated Collapsing Glomerulopathy
Meliambro, K;Li, X;Salem, F;Yi, Z;Sun, Z;Chan, L;Chung, M;Chancay, J;Vy, HMT;Nadkarni, G;Wong, JS;Fu, J;Lee, K;Zhang, W;He, JC;Campbell, KN;
PMID: 33942030 | DOI: 10.1016/j.xkme.2021.02.012
Recent Case reports suggest COVID-19 is associated with collapsing glomerulopathy in African Americans with APOL1 risk alleles, however, it is unclear if disease pathogenesis is similar to HIVAN. Here RNA sequencing analysis of a kidney biopsy specimen from a patient with COVID-19-associated collapsing glomerulopathy and APOL1 risk alleles (G1/G1) revealed similar levels of APOL1 and ACE2 mRNA transcripts as compared to 12 control kidney samples downloaded from the GTEx Portal. Whole genome sequencing of the COVID-19-associated collapsing glomerulopathy kidney sample identified four indel gene variants, three of which are of unknown significance with respect to chronic kidney disease and/or FSGS. Molecular profiling of the kidney demonstrated activation of COVID-19-associated cell injury pathways such as inflammation and coagulation. Evidence for direct SARS-CoV-2 infection of kidney cells was lacking, which is consistent with the findings of several recent studies. Interestingly, immunostaining of kidney biopsy sections revealed increased expression of phospho-STAT3 in both COVID-19-associated collapsing glomerulopathy and HIVAN as compared to control kidney tissue. Importantly, IL-6-induced activation of STAT3 may be a targetable mechanism driving COVID-19-associated acute kidney injury.
Distinct uptake, amplification, and release of SARS-CoV-2 by M1 and M2 alveolar macrophages
Lv, J;Wang, Z;Qu, Y;Zhu, H;Zhu, Q;Tong, W;Bao, L;Lv, Q;Cong, J;Li, D;Deng, W;Yu, P;Song, J;Tong, WM;Liu, J;Liu, Y;Qin, C;Huang, B;
PMID: 33850112 | DOI: 10.1038/s41421-021-00258-1
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) invades the alveoli, where abundant alveolar macrophages (AMs) reside. How AMs respond to SARS-CoV-2 invasion remains elusive. Here, we show that classically activated M1 AMs facilitate viral spread; however, alternatively activated M2 AMs limit the spread. M1 AMs utilize cellular softness to efficiently take up SARS-CoV-2. Subsequently, the invaded viruses take over the endo-lysosomal system to escape. M1 AMs have a lower endosomal pH, favoring membrane fusion and allowing the entry of viral RNA from the endosomes into the cytoplasm, where the virus achieves replication and is packaged to be released. In contrast, M2 AMs have a higher endosomal pH but a lower lysosomal pH, thus delivering the virus to lysosomes for degradation. In hACE2 transgenic mouse model, M1 AMs are found to facilitate SARS-CoV-2 infection of the lungs. These findings provide insights into the complex roles of AMs during SARS-CoV-2 infection, along with potential therapeutic targets.
Investigative Ophthalmology & Visual Science
Zhu, X;Xu, M;Grachtchouk, M;
RESULTS : Short-term lineage tracing data showed that _Lrig1_, _Lgr6_ and _Axin2_ label basal cells in MG ducts and acini. Long-term lineage tracing results showed that clones of labeled cells persist through multiple rounds of ductal and acinar renewal and give rise to differentiated progeny, identifying _Lrig1_+, _Lgr6_+ and _Axin2+_ ductal and acinar basal cells as self-renewing SCs. Forced expression of GLI2ΔN enhanced basal proliferation, caused expansion of _Lrig1_+ SCs, and lead to replacement of lipid-filled meibocytes by proliferative and poorly differentiated acinar cells. Transcriptional profiling of GLI2ΔN-expressing and control MGs revealed that forced GLI2ΔN expression caused greatly increased expression of _Lrig1_ and _Lgr6_ and suppressed expression of meibocyte differentiation genes.
Yang, Y;Wei, Z;Xiong, C;Qian, H;
PMID: 35752810 | DOI: 10.1186/s12985-022-01833-y
Myocardial injury induced by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is reportedly related to disease severity and mortality, attracting attention to exploring relevant pathogenic mechanisms. Limited by insufficient evidence, myocardial injury caused by direct viral invasion of cardiomyocytes (CMs) is not fully understood. Based on recent studies, endosomal dependence can compensate for S protein priming to mediate SARS-CoV-2 infection of CMs, damage the contractile function of CMs, trigger electrical dysfunction, and tip the balance of the renin-angiotensin-aldosterone system to exert a myocardial injury effect. In this review, we shed light on the direct injury caused by SARS-CoV-2 to provide a comprehensive understanding of the cardiac manifestations of coronavirus disease 2019 (COVID-19).
Turco MY, Gardner L, Hughes J, Cindrova-Davies T, Gomez MJ, Farrell L, Hollinshead M, Marsh SG, Brosens JJ, Critchley HO, Simons BD, Hemberger M, Koo BK, Moffett A, Burton GJ.
PMID: 28394884 | DOI: 10.1038/ncb3516
In humans, the endometrium, the uterine mucosal lining, undergoes dynamic changes throughout the menstrual cycle and pregnancy. Despite the importance of the endometrium as the site of implantation and nutritional support for the conceptus, there are no long-term culture systems that recapitulate endometrial function in vitro. We adapted conditions used to establish human adult stem-cell-derived organoid cultures to generate three-dimensional cultures of normal and decidualized human endometrium. These organoids expand long-term, are genetically stable and differentiate following treatment with reproductive hormones. Single cells from both endometrium and decidua can generate a fully functional organoid. Transcript analysis confirmed great similarity between organoids and the primary tissue of origin. On exposure to pregnancy signals, endometrial organoids develop characteristics of early pregnancy. We also derived organoids from malignant endometrium, and so provide a foundation to study common diseases, such as endometriosis and endometrial cancer, as well as the physiology of early gestation.
Wu, CT;Lidsky, PV;Xiao, Y;Cheng, R;Lee, IT;Nakayama, T;Jiang, S;He, W;Demeter, J;Knight, MG;Turn, RE;Rojas-Hernandez, LS;Ye, C;Chiem, K;Shon, J;Martinez-Sobrido, L;Bertozzi, CR;Nolan, GP;Nayak, JV;Milla, C;Andino, R;Jackson, PK;
PMID: 36580912 | DOI: 10.1016/j.cell.2022.11.030
How SARS-CoV-2 penetrates the airway barrier of mucus and periciliary mucins to infect nasal epithelium remains unclear. Using primary nasal epithelial organoid cultures, we found that the virus attaches to motile cilia via the ACE2 receptor. SARS-CoV-2 traverses the mucus layer, using motile cilia as tracks to access the cell body. Depleting cilia blocks infection for SARS-CoV-2 and other respiratory viruses. SARS-CoV-2 progeny attach to airway microvilli 24 h post-infection and trigger formation of apically extended and highly branched microvilli that organize viral egress from the microvilli back into the mucus layer, supporting a model of virus dispersion throughout airway tissue via mucociliary transport. Phosphoproteomics and kinase inhibition reveal that microvillar remodeling is regulated by p21-activated kinases (PAK). Importantly, Omicron variants bind with higher affinity to motile cilia and show accelerated viral entry. Our work suggests that motile cilia, microvilli, and mucociliary-dependent mucus flow are critical for efficient virus replication in nasal epithelia.
