Bader, SM;Cooney, JP;Pellegrini, M;Doerflinger, M;
PMID: 35244141 | DOI: 10.1042/BCJ20210602
Two years after the emergence of SARS-CoV-2, our understanding of COVID-19 disease pathogenesis is still incomplete. Despite unprecedented global collaborative scientific efforts and rapid vaccine development, an uneven vaccine roll-out and the emergence of novel variants of concern such as omicron underscore the critical importance of identifying the mechanisms that contribute to this disease. Overt inflammation and cell death have been proposed to be central drivers of severe pathology in COVID-19 patients and their pathways and molecular components therefore present promising targets for host-directed therapeutics. In our review, we summarize the current knowledge on the role and impact of diverse programmed cell death (PCD) pathways on COVID-19 disease. We dissect the complex connection of cell death and inflammatory signaling at the cellular and molecular level and identify a number of critical questions that remain to be addressed. We provide rationale for targeting of cell death as potential COVID-19 treatment and provide an overview of current therapeutics that could potentially enter clinical trials in the near future.
bioRxiv : the preprint server for biology
Dinnon, KH;Leist, SR;Okuda, K;Dang, H;Fritch, EJ;Gully, KL;De la Cruz, G;Evangelista, MD;Asakura, T;Gilmore, RC;Hawkins, P;Nakano, S;West, A;Schäfer, A;Gralinski, LE;Everman, JL;Sajuthi, SP;Zweigart, MR;Dong, S;McBride, J;Cooley, MR;Hines, JB;Love, MK;Groshong, SD;VanSchoiack, A;Phelan, SJ;Liang, Y;Hether, T;Leon, M;Zumwalt, RE;Barton, LM;Duval, EJ;Mukhopadhyay, S;Stroberg, E;Borczuk, A;Thorne, LB;Sakthivel, MK;Lee, YZ;Hagood, JS;Mock, JR;Seibold, MA;O'Neal, WK;Montgomery, SA;Boucher, RC;Baric, RS;
PMID: 35194605 | DOI: 10.1101/2022.02.15.480515
COVID-19 survivors develop post-acute sequelae of SARS-CoV-2 (PASC), but the mechanistic basis of PASC-associated lung abnormalities suffers from a lack of longitudinal samples. Mouse-adapted SARS-CoV-2 MA10 produces an acute respiratory distress syndrome (ARDS) in mice similar to humans. To investigate PASC pathogenesis, studies of MA10-infected mice were extended from acute disease through clinical recovery. At 15-120 days post-virus clearance, histologic evaluation identified subpleural lesions containing collagen, proliferative fibroblasts, and chronic inflammation with tertiary lymphoid structures. Longitudinal spatial transcriptional profiling identified global reparative and fibrotic pathways dysregulated in diseased regions, similar to human COVID-19. Populations of alveolar intermediate cells, coupled with focal upregulation of pro-fibrotic markers, were identified in persistently diseased regions. Early intervention with antiviral EIDD-2801 reduced chronic disease, and early anti-fibrotic agent (nintedanib) intervention modified early disease severity. This murine model provides opportunities to identify pathways associated with persistent SARS-CoV-2 pulmonary disease and test countermeasures to ameliorate PASC.
Kidney allograft biopsy findings after COVID-19
American journal of transplantation : official journal of the American Society of Transplantation and the American Society of Transplant Surgeons
Daniel, E;Sekulic, M;Kudose, S;Kubin, C;Ye, X;Shayan, K;Patel, A;Cohen, DJ;Ratner, L;Santoriello, D;Stokes, MB;Markowitz, GS;Pereira, MR;D'Agati, VD;Batal, I;
PMID: 34403563 | DOI: 10.1111/ajt.16804
COVID-19 has been associated with acute kidney injury and published reports of native kidney biopsies have reported diverse pathologies. Case series directed specifically to kidney allograft biopsy findings in the setting of COVID-19 are lacking. We evaluated 18 kidney transplant recipients who were infected with SARS-CoV-2 and underwent allograft biopsy. Patients had a median age of 55 years, six were female, and five were Black. Fifteen patients developed COVID-19 pneumonia, of which five required mechanical ventilation. Notably, five of eleven (45%) biopsies obtained within one month of positive SARS-CoV-2 PCR showed acute rejection (four with arteritis, three of which were not associated with reduced immunosuppression). The remaining six biopsies revealed podocytopathy (n=2, collapsing glomerulopathy and lupus podocytopathy), acute tubular injury (n=2), infarction (n=1), and transplant glomerulopathy (n=1). Biopsies performed >1 month after positive SARS-CoV-2 PCR revealed collapsing glomerulopathy (n=1), acute tubular injury (n=1), and non-specific histologic findings (n=5). No direct viral infection of the kidney allograft was detected by immunohistochemistry, in situ hybridization, or electron microscopy. On follow-up, two patients died and most patients showed persistent allograft dysfunction. In conclusion, we demonstrate diverse causes of kidney allograft dysfunction after COVID-19, the most common being acute rejection with arteritis.This article is protected by
Biopreservation and biobanking
Higgs, EF;Flood, BA;Pyzer, AR;Rouhani, SJ;Trujillo, JA;Gajewski, TF;
PMID: 35771982 | DOI: 10.1089/bio.2021.0169
Biobanking during the COVID-19 pandemic presented unique challenges regarding patient enrollment, sample collection, and experimental analysis. This report details the ways in which we rapidly overcame those challenges to create a robust database of clinical information and patient samples while maintaining clinician and researcher safety. We developed a pipeline using REDCap (Research Electronic Data Capture) to coordinate electronic informed consent, sample collection, immunological assay execution, and data analysis for biobanking samples from patients with COVID-19. We then integrated immunological assay data with clinical data extracted from the electronic health record to link study parameters with clinical readouts. Of the 193 inpatients who participated in this study, 138 consented electronically and 56 provided paper consent. We collected and banked blood samples to measure circulating cytokines and chemokines, peripheral immune cell composition and activation status, anti-COVID-19 antibodies, and germline gene polymorphisms. In addition, we collected DNA and RNA from nasopharyngeal swabs to assess viral titer and microbiome composition by 16S sequencing. The rapid spread and contagious nature of COVID-19 required special considerations and innovative solutions to biobank samples quickly while protecting researchers and clinicians. Overall, this workflow and computational pipeline allowed for comprehensive immune profiling of 193 inpatients infected with COVID-19, as well as 89 outpatients, 157 patients receiving curbside COVID-19 testing, and 86 healthy controls. We describe a novel electronic framework for biobanking and analyzing patient samples during COVID-19, and present insights and strategies that can be applied more broadly to other biobank studies.
Ward, JD;Cornaby, C;Kato, T;Gilmore, RC;Bunch, D;Miller, MB;Boucher, RC;Schmitz, JL;Askin, FA;Scanga, LR;
PMID: 35512490 | DOI: 10.1016/j.placenta.2022.04.006
The effect of SARS-CoV-2 severity or the trimester of infection in pregnant mothers, placentas, and infants is not fully understood.A retrospective, observational cohort study in Chapel Hill, NC of 115 mothers with SARS-CoV-2 and singleton pregnancies from December 1, 2019 to May 31, 2021 via chart review to document the infants' weight, length, head circumference, survival, congenital abnormalities, hearing loss, maternal complications, and placental pathology classified by the Amsterdam criteria.Of the 115 mothers, 85.2% were asymptomatic (n = 37) or had mild (n = 61) symptoms, 13.0% had moderate (n = 9) or severe (n = 6) COVID-19, and 1.74% (n = 2) did not have symptoms recorded. Moderate and severe maternal infections were associated with increased C-section, premature delivery, infant NICU admission, and were more likely to occur in Type 1 (p = 0.0055) and Type 2 (p = 0.0285) diabetic mothers. Only one infant (0.870%) became infected with SARS-CoV-2, which was not via the placenta. Most placentas (n = 63, 54.8%) did not show specific histologic findings; however, a subset showed mild maternal vascular malperfusion (n = 26, 22.6%) and/or mild microscopic ascending intrauterine infection (n = 28, 24.3%). The infants had no identifiable congenital abnormalities, and all infants and mothers survived.Most mothers and their infants had a routine clinical course; however, moderate and severe COVID-19 maternal infections were associated with pregnancy complications and premature delivery. Mothers with pre-existing, non-gestational diabetes were at greatest risk of developing moderate or severe COVID-19. The placental injury patterns of maternal vascular malperfusion and/or microscopic ascending intrauterine infection were not associated with maternal COVID-19 severity.
Gastroenterology Clinics of North America
Meringer, H;Wang, A;Mehandru, S;
| DOI: 10.1016/j.gtc.2022.12.001
The gastrointestinal tract (GI) is targeted by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). The present review examines GI involvement in patients with long COVID and discusses the underlying pathophysiological mechanisms that include viral persistence, mucosal and systemic immune dysregulation, microbial dysbiosis, insulin resistance and metabolic abnormalities. Due to the complex and potentially multifactorial nature of this syndrome, rigorous clinical definitions and pathophysiology-based therapeutic approaches are warranted
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.
Reactivation of the Hedgehog pathway in esophageal progenitors turns on an embryonic-like program to initiate columnar metaplasia
Vercauteren Drubbel, A;Pirard, S;Kin, S;Dassy, B;Lefort, A;Libert, F;Nomura, S;Beck, B;
PMID: 33882290 | DOI: 10.1016/j.stem.2021.03.019
Columnar metaplasia of the esophagus is the main risk factor for esophageal adenocarcinoma. There is a lack of evidence to demonstrate that esophageal progenitors can be the source of columnar metaplasia. In this study, using transgenic mouse models, lineage tracing, single-cell RNA sequencing, and transcriptomic and epigenetic profiling, we found that the activation of the Hedgehog pathway in esophageal cells modifies their differentiation status in vivo. This process involves an initial step of dedifferentiation into embryonic-like esophageal progenitors. Moreover, a subset of these cells undergoes full squamous-to-columnar conversion and expresses selected intestinal markers. These modifications of cell fate are associated with remodeling of the chromatin and the appearance of Sox9. Using a conditional knockout mouse, we show that Sox9 is required for columnar conversion but not for the step of dedifferentiation. These results provide insight into the mechanisms by which esophageal cells might initiate columnar metaplasia.
Hoeck JD, Biehs B, Kurtova AV, Kljavin NM, de Sousa E Melo F, Alicke B, Koeppen H, Modrusan Z, Piskol R, de Sauvage FJ.
PMID: 28553937 | DOI: 10.1038/ncb3535
Under injury conditions, dedicated stem cell populations govern tissue regeneration. However, the molecular mechanisms that induce stem cell regeneration and enable plasticity are poorly understood. Here, we investigate stem cell recovery in the context of the hair follicle to understand how two molecularly distinct stem cell populations are integrated. Utilizing diphtheria-toxin-mediated cell ablation of Lgr5+(leucine-rich repeat-containing G-protein-coupled receptor 5) stem cells, we show that killing of Lgr5+ cells in mice abrogates hair regeneration but this is reversible. During recovery, CD34+ (CD34 antigen) stem cells activate inflammatory response programs and start dividing. Pharmacological attenuation of inflammation inhibits CD34+ cell proliferation. Subsequently, the Wnt pathway controls the recovery of Lgr5+ cells and inhibition of Wnt signalling prevents Lgr5+ cell and hair germ recovery. Thus, our study uncovers a compensatory relationship between two stem cell populations and the underlying molecular mechanisms that enable hair follicle regeneration.
Maglic D, Schlegelmilch K, Dost AF, Panero R, Dill M, Calogero RA, Camargo FD.
PMID: 30037824 | DOI: 10.15252/embj.201798642
The mammalian Hippo signaling pathway, through its effectors YAP and TAZ, coerces epithelial progenitor cell expansion for appropriate tissue development or regeneration upon damage. Its ability to drive rapid tissue growth explains why many oncogenic events frequently exploit this pathway to promote cancer phenotypes. Indeed, several tumor types including basal cell carcinoma (BCC) show genetic aberrations in the Hippo (or YAP/TAZ) regulators. Here, we uncover that while YAP is dispensable for homeostatic epidermal regeneration, it is required for BCC development. Our clonal analyses further demonstrate that the few emerging Yap-null dysplasia have lower fitness and thus are diminished as they progress to invasive BCC Mechanistically, YAP depletion in BCC tumors leads to effective impairment of the JNK-JUN signaling, a well-established tumor-driving cascade. Importantly, in this context, YAP does not influence canonical Wnt or Hedgehog signaling. Overall, we reveal Hippo signaling as an independent promoter of BCC pathogenesis and thereby a viable target for drug-resistant BCC.
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.
