Journal of clinical pathology
Humphries, MP;Bingham, V;Abdullah Sidi, F;Craig, S;Lara, B;El-Daly, H;O'Doherty, N;Maxwell, P;Lewis, C;McQuaid, S;Lyness, J;James, J;Snead, DRJ;Salto-Tellez, M;
PMID: 36717223 | DOI: 10.1136/jcp-2022-208525
Interrogation of immune response in autopsy material from patients with SARS-CoV-2 is potentially significant. We aim to describe a validated protocol for the exploration of the molecular physiopathology of SARS-CoV-2 pulmonary disease using multiplex immunofluorescence (mIF).The application of validated assays for the detection of SARS-CoV-2 in tissues, originally developed in our laboratory in the context of oncology, was used to map the topography and complexity of the adaptive immune response at protein and mRNA levels.SARS-CoV-2 is detectable in situ by protein or mRNA, with a sensitivity that could be in part related to disease stage. In formalin-fixed, paraffin-embedded pneumonia material, multiplex immunofluorescent panels are robust, reliable and quantifiable and can detect topographic variations in inflammation related to pathological processes.Clinical autopsies have relevance in understanding diseases of unknown/complex pathophysiology. In particular, autopsy materials are suitable for the detection of SARS-CoV-2 and for the topographic description of the complex tissue-based immune response using mIF.
The American journal of pathology
Ting, C;Aspal, M;Vaishampayan, N;Huang, SK;Riemondy, KA;Wang, F;Farver, C;Zemans, RL;
PMID: 34973949 | DOI: 10.1016/j.ajpath.2021.11.014
ARDS due to COVID-19 and other etiologies results from injury to the alveolar epithelial cell (AEC) barrier resulting in noncardiogenic pulmonary edema, which causes acute respiratory failure; clinical recovery requires epithelial regeneration. During physiologic regeneration in mice, AEC2s proliferate, exit the cell cycle, and transiently assume a transitional state before differentiating into AEC1s; persistence of the transitional state is associated with pulmonary fibrosis in humans. It is unknown whether transitional cells emerge and differentiate into AEC1s without fibrosis in human ARDS and why transitional cells differentiate into AEC1s during physiologic regeneration but persist in fibrosis. We hypothesized that incomplete but ongoing AEC1 differentiation from transitional cells without fibrosis may underlie persistent barrier permeability and fatal acute respiratory failure in ARDS. Immunostaining of postmortem ARDS lungs revealed abundant transitional cells in organized monolayers on alveolar septa without fibrosis. They were typically cuboidal or partially spread, sometimes flat, and occasionally expressed AEC1 markers. Immunostaining and/or interrogation of scRNAseq datasets revealed that transitional cells in mouse models of physiologic regeneration, ARDS, and fibrosis express markers of cell cycle exit but only in fibrosis express a specific senescence marker. Thus, in severe, fatal early ARDS, AEC1 differentiation from transitional cells is incomplete, underlying persistent barrier permeability and respiratory failure, but ongoing without fibrosis; senescence of transitional cells may be associated with pulmonary fibrosis.
Gray-Rodriguez, S;Jensen, MP;Otero-Jimenez, M;Hanley, B;Swann, OC;Ward, PA;Salguero, FJ;Querido, N;Farkas, I;Velentza-Almpani, E;Weir, J;Barclay, WS;Carroll, MW;Jaunmuktane, Z;Brandner, S;Pohl, U;Allinson, K;Thom, M;Troakes, C;Al-Sarraj, S;Sastre, M;Gveric, D;Gentleman, S;Roufosse, C;Osborn, M;Alegre-Abarrategui, J;
PMID: 35107828 | DOI: 10.1002/path.5878
SARS-CoV-2, the causative agent of COVID-19, typically manifests as a respiratory illness although extrapulmonary involvement, such as in the gastrointestinal tract and nervous system, as well as frequent thrombotic events, are increasingly recognised. How this maps onto SARS-CoV-2 organ tropism at the histological level, however, remains unclear. Here, we perform a comprehensive validation of a monoclonal antibody against the SARS-CoV-2 nucleocapsid protein (NP) followed by systematic multisystem organ immunohistochemistry analysis of the viral cellular tropism in tissue from 36 patients, 16 post-mortem cases and 16 biopsies with polymerase chain reaction (PCR)-confirmed SARS-CoV-2 status from the peaks of the pandemic in 2020 and four pre-COVID post-mortem controls. SARS-CoV-2 anti-NP staining in the post-mortem cases revealed broad multiorgan involvement of the respiratory, digestive, haematopoietic, genitourinary and nervous systems, with a typical pattern of staining characterised by punctate paranuclear and apical cytoplasmic labelling. The average time from symptom onset to time of death was shorter in positively versus negatively stained post-mortem cases (mean = 10.3 days versus mean = 20.3 days, p = 0.0416, with no cases showing definitive staining if the interval exceeded 15 days). One striking finding was the widespread presence of SARS-CoV-2 NP in neurons of the myenteric plexus, a site of high ACE-2 expression, the entry receptor for SARS-CoV-2, and one of the earliest affected cells in Parkinson's disease. In the bone marrow, we observed viral SARS-CoV-2 NP within megakaryocytes, key cells in platelet production and thrombus formation. In 15 tracheal biopsies performed in patients requiring ventilation, there was a near complete concordance between immunohistochemistry and PCR swab results. Going forward, our findings have relevance to correlating clinical symptoms to the organ tropism of SARS-CoV-2 in contemporary cases as well as providing insights into potential long-term complications of COVID-19. This article is protected by
Melero, I;Villalba-Esparza, M;Recalde-Zamacona, B;Jiménez-Sánchez, D;Teijeira, Á;Argueta, A;García-Tobar, L;Álvarez-Gigli, L;Sainz, C;Garcia-Ros, D;Toledo, E;Abengozar-Muela, M;Fernández-Alonso, M;Rodríguez-Mateos, M;Reina, G;Carmona-Torre, F;Quiroga, JA;Del Pozo, JL;Cross, A;López-Janeiro, Á;Hardisson, D;Echeveste, JI;Lozano, MD;Ho, LP;Klenerman, P;Issa, F;Landecho, MF;de Andrea, CE;
PMID: 35714708 | DOI: 10.1016/j.chest.2022.06.007
Excessive inflammation is pathogenic in the pneumonitis associated with severe COVID-19. Neutrophils are among the most abundantly present leukocytes in the inflammatory infiltrates and may form neutrophil extracellular traps (NETs) under the local influence of cytokines. NETs constitute a defense mechanism against bacteria but have also been shown to mediate tissue damage in a number of diseases.Could NETs and their tissue-damaging properties inherent to neutrophil-associated functions play a role in the respiratory failure seen in severe COVID-19 patients and how does this relate to the SARS-CoV-2 viral loads, IL-8 (CXCL8) chemokine expression, and cytotoxic T-lymphocytes infiltrates?Sixteen immediate post-mortem lung biopsies were methodically analyzed as exploratory and validation cohorts. NETs were quantitatively analyzed by multiplexed immunofluorescence and correlated with local levels of IL-8 mRNA and the density of CD8+ T-cell infiltration. SARS-CoV-2 presence in tissue was quantified by RT-PCR and immunohistochemistry.NETs were found in the lung interstitium and surrounding the bronchiolar epithelium with interindividual and spatial heterogeneity. NET density did not correlate with SARS-CoV-2 tissue viral load. NETs were associated with local IL-8 mRNA levels. NETs were also detected in pulmonary thrombi and in only one out of eight liver tissues. NET focal presence negatively correlated with CD8+ T-cell infiltration in the lungs.Abundant neutrophils undergoing NETosis are found in the lungs of patients with fatal COVID-19, but no correlation is found with viral loads. The strong association between NETs and IL-8 points to this chemokine as a potentially causative factor. The function of cytotoxic T-lymphocytes in the immune responses against SARS-CoV-2 may be interfered with the presence of NETs.
Kambayashi, Y;Kishi, D;Ueno, T;Ohta, M;Bannai, H;Tsujimura, K;Kinoshita, Y;Nemoto, M;
PMID: 35639190 | DOI: 10.1007/s00705-022-05488-6
Equine coronavirus (ECoV) causes pyrexia, anorexia, lethargy, and sometimes diarrhoea. Infected horses excrete the virus in their faeces, and ECoV is also detected in nasal samples from febrile horses. However, details about ECoV infection sites in the intestinal and respiratory tracts are lacking. To identify the ECoV infection sites in the intestinal and respiratory tracts, we performed an experimental infection study and analysed intestinal and respiratory samples collected from four infected horses at 3, 5, 7, and 14 days post-inoculation (dpi) by real-time reverse transcription polymerase chain reaction (real-time RT-PCR) and in situ hybridization (ISH). Two horses became febrile, but the other two did not. None of the horses had diarrhoea or respiratory signs, and severe cases were not observed in this study. None of the horses showed obvious abnormalities in their intestinal or respiratory tracts. Real-time RT-PCR and ISH showed that ECoV RNA was present throughout the intestinal tract, and ECoV-positive cells were mainly detected on the surface of the intestine. In one horse showing viremia at 3 dpi, ECoV RNA was detected in the lung by real-time RT-PCR, but not by ISH. This suggests that the lung cells themselves were not infected with ECoV and that real-time RT-PCR detected viremia in the lung. The other three horses were positive for ECoV RNA in nasal swabs but were negative in the trachea and lung by real-time RT-PCR and ISH. This study suggests that ECoV broadly infects the intestinal tract and is less likely to infect the respiratory tract.
Choudhary, S;Kanevsky, I;Yildiz, S;Sellers, RS;Swanson, KA;Franks, T;Rathnasinghe, R;Munoz-Moreno, R;Jangra, S;Gonzalez, O;Meade, P;Coskran, T;Qian, J;Lanz, TA;Johnson, JG;Tierney, CA;Smith, JD;Tompkins, K;Illenberger, A;Corts, P;Ciolino, T;Dormitzer, PR;Dick, EJ;Shivanna, V;Hall-Ursone, S;Cole, J;Kaushal, D;Fontenot, JA;Martinez-Romero, C;McMahon, M;Krammer, F;Schotsaert, M;García-Sastre, A;
PMID: 35128980 | DOI: 10.1177/01926233211072767
Coronavirus disease 2019 (COVID-19) in humans has a wide range of presentations, ranging from asymptomatic or mild symptoms to severe illness. Suitable animal models mimicking varying degrees of clinical disease manifestations could expedite development of therapeutics and vaccines for COVID-19. Here we demonstrate that severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection resulted in subclinical disease in rhesus macaques with mild pneumonia and clinical disease in Syrian hamsters with severe pneumonia. SARS-CoV-2 infection was confirmed by formalin-fixed, paraffin-embedded (FFPE) polymerase chain reaction (PCR), immunohistochemistry, or in situ hybridization. Replicating virus in the lungs was identified using in situ hybridization or virus plaque forming assays. Viral encephalitis, reported in some COVID-19 patients, was identified in one macaque and was confirmed with immunohistochemistry. There was no evidence of encephalitis in hamsters. Severity and distribution of lung inflammation were substantially more in hamsters compared with macaques and exhibited vascular changes and virus-induced cytopathic changes as seen in COVID-19 patients. Neither the hamster nor macaque models demonstrated evidence for multisystemic inflammatory syndrome (MIS). Data presented here demonstrate that macaques may be appropriate for mechanistic studies of mild asymptomatic COVID-19 pneumonia and COVID-19-associated encephalitis, whereas Syrian hamsters may be more suited to study severe COVID-19 pneumonia.
Savage, A;Risquez, C;Gomi, K;Schreiner, R;Borczuk, AC;Worgall, S;Silver, RB;
PMID: 36910476 | DOI: 10.3389/fmed.2023.1139397
In addition to the traditional activation of resident receptors by release of local mediators, new evidence favors the existence of exosomes in cell-to-cell communication that mediates delivery of specific cargo to modulate recipient cell function. We report that mast cell exosomes are an additional source of pro-fibrotic substances and constitute a unique pathway for the generation of excess collagen.We use primary human lung fibroblasts (HLFs) to demonstrate the uptake of labeled exosomes isolated from the human mast cell line HMC-1 (MC-EXOs), previously shown to contain protein cargo in common with human mast cell exosomes.The MC-EXO uptake by HLF is to the cytosol and increases both proline hydroxylation in HLF lysate and secreted collagen, within 24 h, which is sustained over 72 h, the same time required for transforming growth factor-β (TGF-β) to activate collagen synthesis in the HLFs. Unlike TGF-β, MC-EXO uptake does not induce fibrillar gene activation or invoke the Smad-nuclear transcription pathway. We show that MC-EXO uptake and TGF-β have an additive effect on collagen synthesis in HLF and postulate that MC-EXO uptake by HLFs is a contributing factor to excess collagen synthesis and represents a unique paradigm for understanding fibrosis.It is known that, in the lungs, mast cells are more activated and increase in number with inflammation, injury and viral infection associated with fibrosis. With the reported increased incidence of post-COVID-pulmonary fibrosis (PCPF), data from patients with severe COVID-19 are presented that show an increase in the mast cell number in lung parenchyma, the site of PCPF. Our findings provide a rationale for targeting multiple fibrogenic pathways in the management of lung fibrosis and the use of mast cell exosomes as a biomarker for the prognostic and diagnostic management of evolving fibrotic lung disease.
Diffuse trophoblast damage is the hallmark of SARS-CoV-2-associated fetal demise
Modern pathology : an official journal of the United States and Canadian Academy of Pathology, Inc
Garrido-Pontnou, M;Navarro, A;Camacho, J;Crispi, F;Alguacil-Guillén, M;Moreno-Baró, A;Hernandez-Losa, J;Sesé, M;Ramón Y Cajal, S;Garcia Ruíz, I;Serrano, B;Garcia-Aguilar, P;Suy, A;Ferreres, JC;Nadal, A;
PMID: 34006935 | DOI: 10.1038/s41379-021-00827-5
Placental pathology in SARS-CoV-2-infected pregnancies seems rather unspecific. However, the identification of the placental lesions due to SARS-CoV-2 infection would be a significant advance in order to improve the management of these pregnancies and to identify the mechanisms involved in a possible vertical transmission. The pathological findings in placentas delivered from 198 SARS-CoV-2-positive pregnant women were investigated for the presence of lesions associated with placental SARS-CoV-2 infection. SARS-CoV-2 infection was investigated in placental tissues through immunohistochemistry, and positive cases were further confirmed by in situ hybridization. SARS-CoV-2 infection was also investigated by RT-PCR in 33 cases, including all the immunohistochemically positive cases. Nine cases were SARS-CoV-2-positive by immunohistochemistry, in situ hybridization, and RT-PCR. These placentas showed lesions characterized by villous trophoblast necrosis with intervillous space collapse and variable amounts of mixed intervillous inflammatory infiltrate and perivillous fibrinoid deposition. Such lesions ranged from focal to massively widespread in five cases, resulting in intrauterine fetal death. Two of the stillborn fetuses showed some evidence of SARS-CoV-2 positivity. The remaining 189 placentas did not show similar lesions. The strong association between trophoblastic damage and placenta SARS-CoV-2 infection suggests that this lesion is a specific marker of SARS-CoV-2 infection in placenta. Diffuse trophoblastic damage, massively affecting chorionic villous tissue, can result in fetal death associated with COVID-19 disease.
Glycated ACE2 receptor in diabetes: open door for SARS-COV-2 entry in cardiomyocyte
Cardiovascular diabetology
D'Onofrio, N;Scisciola, L;Sardu, C;Trotta, MC;De Feo, M;Maiello, C;Mascolo, P;De Micco, F;Turriziani, F;Municinò, E;Monetti, P;Lombardi, A;Napolitano, MG;Marino, FZ;Ronchi, A;Grimaldi, V;Hermenean, A;Rizzo, MR;Barbieri, M;Franco, R;Campobasso, CP;Napoli, C;Municinò, M;Paolisso, G;Balestrieri, ML;Marfella, R;
PMID: 33962629 | DOI: 10.1186/s12933-021-01286-7
About 50% of hospitalized coronavirus disease 2019 (COVID-19) patients with diabetes mellitus (DM) developed myocardial damage. The mechanisms of direct SARS-CoV-2 cardiomyocyte infection include viral invasion via ACE2-Spike glycoprotein-binding. In DM patients, the impact of glycation of ACE2 on cardiomyocyte invasion by SARS-CoV-2 can be of high importance. To evaluate the presence of SARS-CoV-2 in cardiomyocytes from heart autopsy of DM cases compared to Non-DM; to investigate the role of DM in SARS-COV-2 entry in cardiomyocytes. We evaluated consecutive autopsy cases, deceased for COVID-19, from Italy between Apr 30, 2020 and Jan 18, 2021. We evaluated SARS-CoV-2 in cardiomyocytes, expression of ACE2 (total and glycosylated form), and transmembrane protease serine protease-2 (TMPRSS2) protein. In order to study the role of diabetes on cardiomyocyte alterations, independently of COVID-19, we investigated ACE2, glycosylated ACE2, and TMPRSS2 proteins in cardiomyocytes from DM and Non-DM explanted-hearts. Finally, to investigate the effects of DM on ACE2 protein modification, an in vitro glycation study of recombinant human ACE2 (hACE2) was performed to evaluate the effects on binding to SARS-CoV-2 Spike protein. The authors included cardiac tissue from 97 autopsies. DM was diagnosed in 37 patients (38%). Fourth-seven out of 97 autopsies (48%) had SARS-CoV-2 RNA in cardiomyocytes. Thirty out of 37 DM autopsy cases (81%) and 17 out of 60 Non-DM autopsy cases (28%) had SARS-CoV-2 RNA in cardiomyocytes. Total ACE2, glycosylated ACE2, and TMPRSS2 protein expressions were higher in cardiomyocytes from autopsied and explanted hearts of DM than Non-DM. In vitro exposure of monomeric hACE2 to 120 mM glucose for 12 days led to non-enzymatic glycation of four lysine residues in the neck domain affecting the protein oligomerization. The upregulation of ACE2 expression (total and glycosylated forms) in DM cardiomyocytes, along with non-enzymatic glycation, could increase the susceptibility to COVID-19 infection in DM patients by favouring the cellular entry of SARS-CoV2.
Bräuninger, H;Stoffers, B;Fitzek, ADE;Meißner, K;Aleshcheva, G;Schweizer, M;Weimann, J;Rotter, B;Warnke, S;Edler, C;Braun, F;Roedl, K;Scherschel, K;Escher, F;Kluge, S;Huber, TB;Ondruschka, B;Schultheiss, HP;Kirchhof, P;Blankenberg, S;Püschel, K;Westermann, D;Lindner, D;
PMID: 34647998 | DOI: 10.1093/cvr/cvab322
Cardiac involvement in COVID-19 is associated with adverse outcome. However, it is unclear whether cell specific consequences are associated with cardiac SARS-CoV-2 infection. Therefore, we investigated heart tissue utilizing in situ hybridization, immunohistochemistry and RNA-sequencing in consecutive autopsy cases to quantify virus load and characterize cardiac involvement in COVID-19.In this study, 95 SARS-CoV-2-positive autopsy cases were included. A relevant SARS-CoV-2 virus load in the cardiac tissue was detected in 41/95 deceased (43%). MACE-RNA-sequencing was performed to identify molecular pathomechanisms caused by the infection of the heart. A signature matrix was generated based on the single-cell dataset "Heart Cell Atlas" and used for digital cytometry on the MACE-RNA-sequencing data. Thus, immune cell fractions were estimated and revealed no difference in immune cell numbers in cases with and without cardiac infection. This result was confirmed by quantitative immunohistological diagnosis.MACE-RNA-sequencing revealed 19 differentially expressed genes (DEGs) with a q-value <0.05 (e.g. up: IFI44L, IFT3, TRIM25; down: NPPB, MB, MYPN). The upregulated DEGs were linked to interferon pathways and originate predominantly from endothelial cells. In contrast, the downregulated DEGs originate predominately from cardiomyocytes. Immunofluorescent staining showed viral protein in cells positive for the endothelial marker ICAM1 but rarely in cardiomyocytes. The GO term analysis revealed that downregulated GO terms were linked to cardiomyocyte structure, whereas upregulated GO terms were linked to anti-virus immune response.This study reveals, that cardiac infection induced transcriptomic alterations mainly linked to immune response and destruction of cardiomyocytes. While endothelial cells are primarily targeted by the virus, we suggest cardiomyocyte-destruction by paracrine effects. Increased pro-inflammatory gene expression was detected in SARS-CoV-2-infected cardiac tissue but no increased SARS-CoV-2 associated immune cell infiltration was observed.Cardiac injury can be documented in COVID-19, regardless the direct cardiac virus infection and is known to be associated with outcome. However, the direct virus infection of the myocardium leads to transcriptomic alterations and might therefore additionally contribute to pathophysiological processes in COVID-19. Therefore, consequences of cardiac virus infection need to be investigated in future studies, since they might also contribute to long-term effects in case of survival.
Pathogens (Basel, Switzerland)
Magalhães, AC;Ricardo, S;Moreira, AC;Nunes, M;Tavares, M;Pinto, RJ;Gomes, MS;Pereira, L;
PMID: 35335638 | DOI: 10.3390/pathogens11030313
The recently emerged severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has forced the scientific community to acquire knowledge in real-time, when total lockdowns and the interruption of flights severely limited access to reagents as the global pandemic became established. This unique reality made researchers aware of the importance of designing efficient in vitro set-ups to evaluate infectious kinetics. Here, we propose a histology-based method to evaluate infection kinetics grounded in cell microarray (CMA) construction, immunocytochemistry and in situ hybridization techniques. We demonstrate that the chip-like organization of the InfectionCMA has several advantages, allowing side-by-side comparisons between diverse cell lines, infection time points, and biomarker expression and cytolocalization evaluation in the same slide. In addition, this methodology has the potential to be easily adapted for drug screening.
Stebbings, R;Armour, G;Pettis, V;Goodman, J;
PMID: 34865878 | DOI: 10.1016/j.vaccine.2021.11.028
Biodistribution studies of adenovirus-based vaccines support their clinical development by evaluating their spread and persistence following in vivo administration. AZD1222 (ChAdox1 nCov-19) is a replication-deficient non-human adenovirus-vectored vaccine for coronavirus disease 2019. In this nonclinical study, the biodistribution of AZD1222 was assessed in mice for 29 days following intramuscular injection. Results show that AZD1222 was safe and well tolerated, with a spread that was largely confined to administration sites and the proximal sciatic nerve, with low levels observed in sites that are involved in rapid clearance of particulates by the reticuloendothelial system. Accordingly, levels of AZD1222 decreased from Day 2 to Day 29, indicating clearance. There were no quantifiable levels of AZD1222 in the blood, brain, spinal cord, and reproductive tissue, suggesting a lack of widespread or long-term distribution of AZD1222 vector DNA throughout the body following its administration.