| T56 |
0-1792 |
Sentence |
denotes |
The SARS-CoV 3a protein contains oligosaccharides with direct evidence that sialic acids play a critical role in human coronavirus infection.15 It has been just shown that the attachment of coronaviruses to the surface of respiratory cells is mediated by the spike (S) viral protein, which binds not only to the angiotensin-converting enzyme 2 (ACE-2) receptor for entry16 but also to sialic acid–containing glycoproteins and gangliosides on cell surfaces.15 Such a dual receptor/attachment is proposed to be a reason for the increased transmissibility of COVID-19 compared with SARS-CoV that binds only to ACE-2 receptor.15,16 Of relevance to GBS is that various gangliosides, most commonly those containing either a disialosyl moiety, such as GD1b, GQ1b, and GT1b, or 2 gangliosides that share epitopes with GM2, or a combination of GM2 and GM1, GM1 and GD1b, can serve as antigens in patients with neuropathies.17 When IgM recognizes the Gal (pl-3) GalNAc moiety of GM1, which is found on the surface of motor neurons, there is clinically a motor neuropathy, but if recognizes epitopes containing disialosyl groups of GDlb, which is present on the dorsal root ganglionic neurons, there is sensory ataxic neuropathy.17 Immunization of rabbits with GDlb also causes sensory ataxic neuropathy mimicking the human disease.18 Of interest, the first described patient with sensory ataxic neuropathy and GDlb antibodies had also ophthalmoplegia,19 as seen in MFS and the present series.10 As COVID-19 spike interacts with the GalNAc residue of GM1 and ganglioside dimers for anchoring to cell surface gangliosides,15 cross-reactivity between epitopes within the COVID-19 spike-bearing gangliosides and signature sugar residues of surface peripheral nerve glycolipids is a very likely possibility. |
