Thread by @vipintukur

#Retinal involvement in #Covid19 and possibly also in Long-Covid

There is more to #SARS2 than meets the eye:

1-Coronavirus not only infects the human retina, but can also replicate in it!

2-The so-called ‘long-Covid’ symptoms may include degenerative retinal disease. 1/

Which cells in the retinal organoids are affected?

The researchers analyzed the organoids under a fluorescence microscope. 2/

With the help of different immune markers for the different cell types of the retina & with a #fluorescent antibody against the #nucleoprotein (N-protein) of #SARS2, it was shown that mainly two cell layers of the retinal organoids were infected. 3/

They found many of the N-protein-stained cells were in the outer nuclear layer of the organoids. This is the layer that contains the cell bodies of the photoreceptors - the cones and rods that convert incoming light into nerve impulses. 4/

Some of these cells with the N-protein actually had the typical appearance of the light-sensitive cells. 5/

However, the cell type in which they most frequently detected the N-protein of #SARS2 is retinal #ganglion cells. These cells are located in the most inner cell layer of the retina and transmit all signals from the retina to the brain via the optic nerve. 6/

This current retina-organoid study shows that infection with #SARS2 can have direct pathological consequences for retinal ganglion cells, even though visual impairment is not common in patients with Covid-19. 7/

mpg.de/18453648/0322-…