The immunology of COVID-19: is immune modulation an option for treatment?

Abstract

In December, 2019, an outbreak of COVID-19 emerged in Wuhan, China and quickly spread globally. As of May 7, 2020, there were 3 672 238 confirmed infections and 254 045 deaths attributed to COVID-19. Evidence has shown that there are asymptomatic carriers of COVID-19 who can transmit the disease to others. The virus incubation time shows a wide range (0-24 days) and the virus displays a high infectivity. It is therefore urgent to develop an effective therapy to treat patients with COVID-19 and to control the spread of the causative agent, severe respiratory syndrome coronavirus 2. Repurposing of approved drugs is widely adopted to fight newly emerged diseases such as COVID-19, as these drugs have known pharmacokinetic and safety profiles. As pathological examination has confirmed the involvement of immune hyperactivation and acute respiratory distress syndrome in fatal cases of COVID-19, several disease-modifying anti-rheumatic drugs (DMARDS), such as hydroxychloroquine and tocilizumab, have been proposed as potential therapies for the treatment of COVID-19. In this Review, we discuss the immunological aspects of COVID-19 and the potential implication of DMARDs in treating this disease.

Figure

Potential mechanisms of action for DMARDs in COVID-19 DMARDs could target different stages of the virus infection and immune activation. AT2=alveolar type 2. DMARDs=disease modifying anti-rheumatic drugs. GM-CSF= granulocyte-macrophage colony stimulating factor. IFNγ= interferon gamma. IL=interleukin. IP-10=interferon gamma-induced protein 10. MCP-1=monocyte chemoattractant protein-1. SARS-CoV-2=severe respiratory syndrome coronavirus 2. TNFα=tumor necrosis factor alpha.