Introduction
A novel coronavirus, named the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) by the WHO, was first reported in Wuhan, China in December 2019. SARS-CoV-2 causes Corona Virus Disease 2019 (COVID-19), and typical COVID-19 symptoms include dry cough, fever and fatigue. [1,2] Since its emergence, SARS-CoV-2 has spread rapidly all over the world, arousing widespread concern. To date, the viral nucleic acid test remains the main diagnostic tool used to detect COVID-19, whereas serum immunoglobulin G (IgG) and immunoglobulin M (IgM) antibodies can be used to detect the SARS-CoV-2 infection.[3] Laboratory examination plays a vital role in the diagnosis and treatment of COVID-19, wherein relevant test indicators may provide evidence-based support for clinicians. This article attempts to show a possible connection between matrix metalloproteinase 3 (MMP3) and COVID-19.
MMP3 is an important member of a large family of matrix metalloproteinases (MMPs) containing zinc-dependent endopeptidases. Matrix degradation and remodeling have been recognized as the main function of MMPs. However, subsequent studies reveal that MMPs may participate in diverse pathophysiological processes, such as the regulation of inflammatory and immune responses as well as cell-cell communication, among others. Reportedly, in addition to the above functions, MMP3 also activates other matrix metalloproteinases in the family. [4,5] In particular, it participates in many physiological and pathological processes that are associated with the inflammatory process. For example, studies have confirmed that MMP3 levels may be used to monitor the activity of rheumatoid arthritis and to predict its severity.[6,7] Recent studies have investigated the effects of MMP3 on respiratory disorders, including acute lung injury (ALI), acute respiratory distress syndrome (ARDS), pulmonary fibrosis, and lung cancer.[4,8]Therefore, this study makes a major contribution to research on COVID-19 by demonstrating the significance of MMP3 and providing ideas for future scientific research.