Table 2.

Summary of some of the most relevant cytopathic effects affecting tissues and organs in individuals infected by SARS-CoV-2, as well as their corresponding manifestations. It should be noted that not all these alterations occur at the same time in all patients since they depend on several factors, such as the severity of the infection, age, and health status of the individual, among others.

Organelle	Affected Cell Subset(s) or Regions	Cytopathy Manifestation(s)	References
Central nervous system	Cortex, hippocampus, and hypothalamus	Neuronal apoptosis through Caspase-3	[128]
	Ventral brain blood vessels	Structural alterations	[128,129]
	Microglia	Morphological alterations	[128]
	Limbic system	Microstructural changes and volume loss	[130]
Respiratory system	Airway epithelium (ciliated cells, secretory cells, and type II alveolar cells)	Formation of viral plaques, cilia shedding and internalization, detachment of infected cells, cell death, and epithelial barrier damage	[114,131,132,133]
	Multiciliated cells of the upper respiratory epithelium	Dedifferentiation through FOXJ1 downregulation	[134,135]
	Lower respiratory tract	Hyaline membrane or platelet-fibrin thrombus formation, accumulation of protein exudates, pneumocytic desquamation, diffuse alveolar damage, atypical pneumocytic hyperplasia, and syncytia	[122,131,136]
	Type II pneumocytes	Morphological alterations of mitochondria, accumulation of lipid and protein droplets, distended ER cisternae	[122,136]
Circulatory system	Endothelium	Loss of endothelial integrity, cell detachment, endothelial dysfunction, alteration of the RAAS system, increased endothelial permeability, hypercoagulation, hypofibrinolysis, and prothrombotic states, increased mitochondrial ROS production, downregulation of ACE2 and eNOS	[24,137,138,139,140]
	Inhibition of host mRNA export from the nucleus	nsp1 protein	[120]
	Cardiac tissue (especially cardiomyocytes)	Myocardial hypertrophy, cytokine production, acute myocardial infarction, interstitial edema, contractile deficits and sarcomere disassembly, necrosis, and cell death, lymphocytic inflammation, small vessel coronary artery disease	[141,142]
Immune system	T cells	Severe lymphopenia, cytokine release syndrome, decreased IFN-γ-producing CD4+ T cell population, T cell depletion, alterations in Treg cells, T cell exhaustion	[81,143,144,145]
	Lymph nodes and spleen	Necrosis, tissue degeneration, macrophage proliferation, atrophy	[143]
Kidney	Renal cells (in general)	Cell detachment, tubular necrosis, inflammation of the ER, alterations of parietal epithelial cells, arteriosclerosis, protein absorption droplets, syncytia formation	[146]
	Podocytes and proximal tubular cells	Hyperplasia, hypertrophy, tubular necrosis, loss of proteins in Bowman’s capsule, alteration of mitochondria, collapsing glomerulopathy	[146,147]
Digestive system	Intestinal epithelium	Disruption of the epithelium integrity, syncytia formation, digestive tract motility and intestinal permeability, alteration of the intestinal microbiome and of the immune system, impaired function of mature enterocytes, overexpression of enzymes	[24,177,185]
	Liver	Inflammation, hepatomegaly, hepatocytolysis, enzyme release	[148]