**5. Conclusions**

COVID-19 is an emergent and ongoing disease with substantial public health and sociological implications. It is clear that inflammation underlies severe COVID-19, and so the biological mechanisms by which this occurs are of substantial interest. Monocytes and macrophages are important innate immune cells that appear to play central roles in COVID-19, as they infiltrate infected tissues and produce pro-inflammatory cytokines during infection. Some current biologic and non-steroidal anti-inflammatory therapies which may be efficacious in treating COVID-19 have known effects on macrophages and monocytes. However, these have primarily been used systemically, so the utility of directly targeting mononuclear phagocytes as a therapeutic for COVID-19 remains in need of investigation. A brief summary of evidence for anti-inflammatory drugs used to treat COVID-19 is presented in **Table 1** below.

Future studies are needed to define the molecular mechanisms by which monocytes and macrophages respond to SARS-CoV-2, either due to direct infection or due to signaling from nearby infected cells. A fuller understanding of how myeloid cells become activated during COVID-19 will allow for more targeted therapies to be developed. These may be more efficacious than the current systemic anti-inflammatory treatments outlined in Section 4 above, as they would represent evidencebased strategies for treating hyperinflammation during severe COVID-19.


#### **Table 1.**

*Targeting COVID-19 with anti-inflammatory drugs.*

*Targeting Mononuclear Phagocytes to Treat COVID-19 DOI: http://dx.doi.org/10.5772/intechopen.98967*
