Dendritic cells in COVID-19 immunopathogenesis: insights for a possible role in determining disease outcome

Abstract

SARS-CoV-2 is the causative agent of the COVID-19 pandemic. This novel coronavirus emerged in China, quickly spreading to more than 200 countries worldwide. Although most patients are only mildly ill or even asymptomatic, some develop severe pneumonia and become critically ill. One of the biggest unanswered questions is why some develop severe disease, whilst others do not. Insight on the interaction between SARS-CoV-2 and the immune system and the contribution of dysfunctional immune responses to disease progression will be instrumental to the understanding of COVID-19 pathogenesis, risk factors for worst outcome, and rational design of effective therapies and vaccines. In this review we have gathered the knowledge available thus far on the epidemiology of SARS-COV-2 infection, focusing on the susceptibility of older individuals, SARS-CoV-2-host cell interaction during infection and the immune response directed at SARS-CoV-2. Dendritic cells act as crucial messengers linking innate and adaptative immunity against viral infections. Thus, this review also brings a focused discussion on the role of dendritic cells and their immune functions during SARS-CoV-2 infection and how immune evasion strategies of SARS-CoV-2 and advancing age mediate dendritic cell dysfunctions that contribute to COVID-19 pathogenesis and increased susceptibility to worst outcomes. This review brings to light the hypothesis that concomitant occurrence of dendritic cell dysfunction/cytopathic effects induced by SARS-CoV-2 and/or aging may influence disease outcome in the elderly. Lastly, a detailed discussion on the effects and mechanisms of action of drugs currently being tested for COVID-19 on the function of dendritic cells is also provided.

Keywords:

• Aging
• COVID-19
• dendritic cells
• immunosenescence
• SARS-CoV-2

Disclosure statement

The authors report no conflicts of interests.

ORCID

Sergio Marques Borghi http://orcid.org/000-0002-6978-7505

Additional information

Notes on contributors

Sergio Marques Borghi

RCB, MSH, and SMB conceived the idea of the article, did the search in bibliographical databases and the literature review. MSH and SMB developed the final draft of the manuscript. All authors contributed to the content, critical review, and approved the final version of the manuscript.