M1 Phenotype Macrophages, Chronic Inflammation, and SARS-CoV-2
Prolonged proinflammatory state from SARS-CoV-2 particles
A 2022 article by Chau and Sugimara titled “Locked in a proinflammatory state” describes prolonged inflammation triggered by SARS-CoV-2 particles.
What’s notable about this short article is the authors outline the actions of macrophages (part of the innate immune system), and their relationship to cytokine storms in COVID-19. Macrophages migrate to infected or damaged tissue sites in the body to eliminate a pathogen or damaged cells (it’s actually monocytes that circulate and then tranform into macrophages in tissues). Once a macrophage encounters a pathogen (e.g., bacteria, virus) or components of dying cells they release proinflammatory cytokines to help strenghten an overall immune response.
Through the action of macrophages tissue pathogens are neutralized and removed from the site of infection. Once the pathogen has been eliminated macrophages stop producing proinflammatory cytokines and begin secreting anti-inflammatory chemicals to promote healing.
M1 and M2 Macrophages
Macrophages exist in different phenotypes called M1 and M2. The M1 macrophage is proinflammatory and an M2 macrophage anti-inflammatory. Again, once the job of neutralizing a pathogen is complete the M1 changes its phenotype to an M2 to initiate tissue healing.
The authors describe that SARS-CoV-2 and its associated particles (these ‘particles’ are not described in detail) prevent MI macrophages from changing into M2 macrophages. This occurence causes persistent inflammation and potential tissue damage. The main proinflammatory cytokine produced is interleukin-6 (IL-6), but likely others occur too. What’s unique about SARS-CoV-2 in this discussion is another viral species did not acheive the same result with regards to IL-6 elevations. However, viral RNA in general appear to play a significant role in preventing the M1 to M2 transformation.
What was not discussed in this article was mRNA injections. The focus was solely on SARS-CoV-2 infections. As mentioned previously the term ‘particles’ was not defined, but understanding the pathogenic properties of SARS-CoV-2 one may assume the spike protein is one of the ‘particles’ involved in inhibiting M1 macrophages from changing into M2 macrophages.
Conclusion
Cytokine storm can be an indicator of a poor disease prognosis. Certain individuals are more prone to this event and it appears to contribute to long-term problems associated with long-COVID. However, it’s not just a SARS-CoV-2 infection that is causing chronic problems, but the spike protein induced into production from mRNA injections is a major issue too. Although not discussed in this eLife article it is possible the mRNA injection products (i.e., spike) may prevent transformation of M1 to M2 macrophages in suspectible individuals.