Journal: Annals of diagnostic pathology

Article Title: Severe COVID-19: A multifaceted viral vasculopathy syndrome.

doi: 10.1016/j.anndiagpath.2020.151645

Figure Lengend Snippet: Fig. 5. Detection of SARS-CoV-2 RNA and capsid proteins in organs other than the lung and skin. SARS-CoV-2 RNA was analyzed in the liver (panel A), heart (panel B), kidney (panel C) and spleen (not shown) in cases where a very high viral load was present in the lung (panels D and E). Note that either no or very rare (no more than 3+ cells/400× field) viral positive cells were present in these other organs (circles); the infected cells had the morphology of macrophages These same organs were interrogated for the ACE2 receptor on endothelial cells and either none were evident (panel F, spleen) or less than 10% of the endothelial cells expressed the viral receptor in these organs. Viral capsid protein was not evident in the spleen microvessels (panel G) and rarely present in the microvessels of other organs (kidney panel H, circle) where they did track with IL6 and caspase 3, data not shown.

Article Snippet: Each of the other antibodies was from ABCAM (Cambridge, Massachusetts, USA) with the exception of ACE2 (cat # 3215) (PROSCI, Poway, California, USA) and optimal pretreatment in each case was 30 min with the Leica EDTA antigen retrieval solution.

Techniques: Infection

Journal: Annals of diagnostic pathology

Article Title: Severe COVID-19: A multifaceted viral vasculopathy syndrome.

doi: 10.1016/j.anndiagpath.2020.151645

Figure Lengend Snippet: Fig. 4. Detection of SARS-CoV-2 RNA and capsid proteins in the lungs of people who died of COVID-19. The lung in fatal COVID-19 shows marked heterogeneity. Panel A shows a histologically unremarkable area of lung. In the serial section, viral RNA was evident in rare cells (circles) that had the morphology of macrophages (panel B) and did co-express with CD68 (data not shown). In adjacent areas the septal capillaries were markedly expanded (panel C). This was associated with a very high viral load where the viral genomes localized to the macrophages (circles) and septal capillaries (arrows). Although the viral RNA in the septal capillaries often showed a thin, linear pattern, at times the zone containing viral RNA was much expanded and associated with degenerated virus (panel E, rectangle). The areas of high viral load and septal capillary injury were associated with strong expression of TLR7 (panel F; signal red) and caspase 3 (panel G, signal red); however, IL6 was much less evident (panel H, signal red). Co-expression of C4d and the envelope protein of SARS-CoV2 in the areas of septal damage were analyzed by the Nuance system. The C4d is seen as fluorescent green (panel I), the envelope protein as fluorescent red (panel J) and the merged image shows the cells in the septal capillaries that contain both proteins as fluorescent yellow (panel K). Panel L shows co-expression of ACE2 (green) and spike protein (red); note that the spike protein strongly co-localizes with ACE2 on the endothelial (yellow). (For interpretation of the references to color in this figure legend, the reader is referred to the web version of this article.)

Article Snippet: Each of the other antibodies was from ABCAM (Cambridge, Massachusetts, USA) with the exception of ACE2 (cat # 3215) (PROSCI, Poway, California, USA) and optimal pretreatment in each case was 30 min with the Leica EDTA antigen retrieval solution.

Techniques: Virus, Expressing

Journal: Annals of diagnostic pathology

Article Title: Severe COVID-19: A multifaceted viral vasculopathy syndrome.

doi: 10.1016/j.anndiagpath.2020.151645

Figure Lengend Snippet: Fig. 6. Detection of SARS-CoV-2 RNA and capsid proteins in the skin and subcutaneous fat. Serial section analyses demonstrated that the same microvessels of the skin in people who died of COVID-19 showed endothelial localization of the viral membrane protein (panel A), activated caspase 3 (panel B), p38 (panel C, signal red), TNF α (panel D) and the viral spike protein (panel E, signal red). However, viral RNA was not detected by in situ hybridization (panel F); consistent with this finding was the lack of TLF7 expression (panel G); compare to TLR7 expression in lung in areas with infectious virus (Fig. 1, panel F). Neither viral capsid proteins (panel H) nor caspase 3/IL6/TNF alpha (not shown) were evident in the skin microvessels in people with mild SARS-CoV-2 infection. Panel I (signal red) shows the strong expression of ACE2 in the microvessels of the subcutaneous fat in people who died of COVID-19. Co-expression experiments showed strong co-localization of C4b and the viral spike protein in the endothelial cells of these microvessels (panel J), of the complement cascade activator MASP2 and viral spike protein (panel K) and of the viral envelope protein and TNF α (panel L) as well as the endothelial cell marker CD31 (data not shown). (For interpretation of the references to color in this figure legend, the reader is referred to the web version of this article.)

Article Snippet: Each of the other antibodies was from ABCAM (Cambridge, Massachusetts, USA) with the exception of ACE2 (cat # 3215) (PROSCI, Poway, California, USA) and optimal pretreatment in each case was 30 min with the Leica EDTA antigen retrieval solution.

Techniques: Membrane, In Situ Hybridization, Expressing, Virus, Infection, Marker

Journal: Annals of diagnostic pathology

Article Title: Severe COVID-19: A multifaceted viral vasculopathy syndrome.

doi: 10.1016/j.anndiagpath.2020.151645

Figure Lengend Snippet: Fig. 7. Molecular correlates of COVID-19 in the brain. Panels A and B show representative histologic changes in the microvessels in the gray matter of the brain from people who died of COVID-19. Note the microthrombus (panel A) and the degenerated microvessel in which the endothelial nuclei are not evident (panel B). Panels C/D show that ACE2 receptor is expressed robustly in the endothelia of microvessels but not of the larger arterioles. Serial section analysis shows that the endothelial cells of the microvessels also the viral spike protein (panel E), IL6 (panel F) and TNF α (panel G). Note that the latter co-localizes with Cd4 (panels G-I) as does IL6 and the spike protein (panel J), C4d and the spike protein (panel K) and the viral membrane protein with caspase 3 (panel L); all co-localization is evident as fluorescent yellow. (For interpretation of the references to color in this figure legend, the reader is referred to the web version of this article.)

Article Snippet: Each of the other antibodies was from ABCAM (Cambridge, Massachusetts, USA) with the exception of ACE2 (cat # 3215) (PROSCI, Poway, California, USA) and optimal pretreatment in each case was 30 min with the Leica EDTA antigen retrieval solution.

Techniques: Membrane