In this study, the authors performed a comprehensive histological and spatial transcriptomic assessment of a patient with MS who had died of COVID-19-associated respiratory failure and compared findings with a non-MS patient with COVID-19 to address: (1) whether an impaired BBB in MS facilitates viral entry to the CNS and (2) whether COVID-19-associated immune dysregulation leads to MS lesion (re)activation. The study involved a single case of a COVID-19-affected patient with a long-standing history of progressive MS. They found viral transcripts in the choroid plexus but not in brain parenchyma either within demyelinated lesions or normal-appearing tissue. The authors claimed that their findings provide no evidence for MS disease exacerbation or lesion (re)activation. These results are in line with recent clinical studies on stable disease in patients with COVID-19 with other autoimmune diseases. Importantly, this study further highlights the significance of CNS barriers, such as the choroid plexus (CP), as a critical entry point for SARS-CoV-2 and calls for further studies to provide more insight into the underlying mechanisms.
DOI: 10.1212/NXI.0000000000000957