Biology

Virology

Proteases

Biochemistry

Fibrinolysis

Furin

Coronavirus disease 2019 (COVID-19)

Immunology

Plasmin

Enzyme

Infectious disease (medical specialty)

Internal medicine

Infectivity

Medicine

Virus

Hyperfibrinolysis

Disease

Physiological Reviews

Patients with hypertension, diabetes, coronary heart disease, cerebrovascular illness, chronic obstructive pulmonary disease, and kidney dysfunction have worse clinical outcomes when infected with SARS-CoV-2, for unknown reasons. The purpose of this review is to summarize the evidence for the existence of elevated plasmin(ogen) in COVID-19 patients with these comorbid conditions. Plasmin, and other proteases, may cleave a newly inserted furin site in the S protein of SARS-CoV-2, extracellularly, which increases its infectivity and virulence. Hyperfibrinolysis associated with plasmin leads to elevated D-dimer in severe patients. The plasmin(ogen) system may prove a promising therapeutic target for combating COVID-19.

Elevated Plasmin(ogen) as a Common Risk Factor for COVID-19 Susceptibility