**4.2 CD47- SIRP**α

CD47 is a protein that can be found on the surface of various cells, including cancer cells. Its primary function is to act as a "do not eat me" signal that prevents phagocytosis, the process by which phagocytic cells destroy other cells. This is achieved by CD47 interacting with its receptor, SIRPα, which inhibits the activation of phagocytic pathways, ultimately blocking phagocytosis. The CD47-SIRPα interaction is a crucial component of immune tolerance, helping to differentiate between self and non-self and prevent the destruction of healthy cells. Despite its role in immune tolerance, researchers are investigating the potential for using the CD47-SIRPα interaction as a strategy for cancer therapy. By blocking this interaction, the phagocytic ability of the immune system can be enhanced, which may lead to increased removal of cancer cells. This can be achieved through the use of


#### **Table 2.**

*Some examples of immune check point inhibitors that induces cellular phagocytosis.*

anti-CD47 monoclonal antibodies or small molecule inhibitors of the CD47-SIRPα interaction, such as Hu5F9-G4 or Sen177. This approach has promising potential as a cancer therapy strategy (**Table 2**) [14, 45, 56, 62–66].

#### **4.3 CD24-SIGLEC10**

CD24 and SIGLEC10 are cell surface markers expressed on immune cells. CD24 is primarily expressed on certain B cells and SIGLEC10 is expressed on immune cells called macrophages and myeloid-derived suppressor cells. Both CD24 and SIGLEC10 have been shown to act as immune checkpoint molecules, meaning they help regulate immune responses and prevent overactive immune responses.

Targeting CD24 and SIGLEC10 with immunotherapies has shown promising results in preclinical studies and is being actively investigated as a potential treatment for cancer [8, 9].
