Figure 6.

a) Schematic overview of registration of decentrally archived COVID-19 autopsy tissue samples. Samples are categorized into central nervous system, thorax, intraperitoneal space and retroperitoneal space. b) Available tissues from registered COVID-19 autopsies for different fixation methods (minimum N=18674 tissues from 1129 COVID-19 autopsies, numbers represent different organs/tissues, not total amount of samples). Decentrally archived samples from COVID-19 autopsy tissue comprise mainly formalin-fixed, paraffin-embedded samples, followed by formalin-fixed, cryopreserved and otherwise preserved biomaterials e.g., in gutaraldehyde for electron microscopy, or in RNA preserving fixation medium for RNA studies). CNS samples appear overrepresented in comparison to non-CNS samples due to numerous sampling localizations, compared to less detailed sampling localizations for non-CNS samples.

CN = cranial nerve; CNS = central nervous system; FFPE = formalin-fixed, paraffin embedded; LC = locus coeruleus; MO = medulla oblongata; SN = substantia nigra; VPM = nucleus ventralis posteromedialis