Table 2.

Experimental and clinical studies in Alfa and Beta coronavirus with potential invasion to the nervous system.

Viruses	Receptor	Human tissue expression	Studies suggesting neurotropism	Associated neurological diseases
Alphacoronaviruses
HCV-229E	APN	Glial cells, Neural cells, Pericytes, Astrocytes, Lung fibroblasts, Proximal renal tubule, Enterocytes, Granulocytes, Monocytes [64]	Lachane et al, 1998 * [64]	MS [25]
HCV-NL63	ACE2	Lung epithelium, Gut epithelium, Brain, Heart Kidney [15]	None	None
Betacoronaviruses
HCV-OC43	9-O-acetylated sialic acid (9-O-Ac-Sia)		Junwei Niu et al, 2020 **. [65] Anna Nilson et al, 2020 *. [66] Mathieu Dubé et al 2018 **. [67] Jacomy H et al, 2006 ** [48]. N Arbour et al, 2000 *. [25]	Encephalitis [66] MS [25]
SARS-CoV	ACE2	Lung epithelium, Gut epithelium, Brain, Heart Kidney [15]	Netland et al, 2008 **. [8] Xu et al, 2005 *. [68] Gu et al, 2005 *. [69] Tsai et al, 2005*. [37] Ding et al, 2004 *. [9]	Polyneuropathy [37,61] Myopathy [38] Stroke [52]
MERS-CoV	DPP4	Pneumocytes, Renal tubular epithelial cells, Endothelial cells, T-cells, Placenta, Liver, Skeletal muscle, Heart, Brain, Pancreas [70]	Li Kai et al., 2016 **[10] Y. M. Arabi et al, 2015 *. [35] Algahatani et al, 2016 *15	Polyneuropathy [36] Encephalitis [63] Stroke [35]
SARS-CoV-2	ACE2	Lung epithelium, Gut epithelium, Brain, Heart Kidney [15]	Ling Mao et al., 2020 *. [6]	Polyneuropathy [6,39,41,42,43,44,45,46,47] Stroke [6,54,59]

^*Observational study/case report.

^**Experimental studies.