Figure - PMC

Skip to main content

An official website of the United States government

Here's how you know

Here's how you know

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you've safely connected to the .gov website. Share sensitive information only on official, secure websites.

View full-text article in PMC

. 2020 Oct 31;65:101205. doi: 10.1016/j.arr.2020.101205

Search in PMC
Search in PubMed
View in NLM Catalog
Add to search

© 2020 Elsevier B.V. All rights reserved.

Since January 2020 Elsevier has created a COVID-19 resource centre with free information in English and Mandarin on the novel coronavirus COVID-19. The COVID-19 resource centre is hosted on Elsevier Connect, the company's public news and information website. Elsevier hereby grants permission to make all its COVID-19-related research that is available on the COVID-19 resource centre - including this research content - immediately available in PubMed Central and other publicly funded repositories, such as the WHO COVID database with rights for unrestricted research re-use and analyses in any form or by any means with acknowledgement of the original source. These permissions are granted for free by Elsevier for as long as the COVID-19 resource centre remains active.

PMC Copyright notice

Fig. 5 — The immune hypothesis. This hypothesis encompasses age-related impairment of immune response and protection against SARS-CoV-2 and immunopathology. Immune response includes humoral immunity (i.e., antibody response) and cell-mediated immunity (CMI) (right). While age-related immunosenescence is believed to weaken immune protection, vaccination enhances it. Inflammaging and cytokine storm may lead to Immunopathology (left). Not all immune responses are protective as antibody-dependent enhancement (ADE) in humoral immunity may promote SARS-CoV-2 infection while T_h17 response in CMI may contribute to cytokine storm. Anti-IL-6 therapy with monoclonal antibodies against either IL-6 or IL-6 receptor currently in clinical trials can block cytokine storm and its downstream event and/or suppress T_h17 response. Age-related decrease of physiological reserve in respiratory and other organ systems may also contribute to vulnerability. Together, they lead to disproportionately severe COVID-19 and high mortality in older adults.