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

. 2021 Sep 23;12:652252. doi: 10.3389/fimmu.2021.652252

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

Copyright © 2021 Labarrere and Kassab

This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.

PMC Copyright notice

Alveolus showing IgM response to coronavirus infection. [1] The arrival of coronaviruses into the alveolus generates an immediate IgM response mediated by innate and adaptive IgM antibodies. The IgM response in association with surfactant proteins D and A (SP-D and SP-A) facilitate virus neutralization and virus-infected apoptotic cell removal. [2] Innate and adaptive IgM participate in the macrophage-mediated removal of alveolar apoptotic cells through pattern recognition protein receptors (PRPRs) avoiding inflammation. [3] Virus-infected apoptotic cells are phagocytosed with the help of SP-D and SP-A through PRPRs. Recruitment of B1a cells into the alveolar wall under the stimulation of interleukin (IL)-17A via IL-17 receptor (IL-17R) and nuclear factor (NF) κB activation generate plasma cells that release IgM into the wall that is transported to the alveolus via polymeric immunoglobulin receptors (pIgRs). Viral particles bind IgM and are phagocytosed via Fcα/μ receptors (Fcα/μRs). lysoPC, lysophosphatidylcholine.