How do Macrophages Work

Macrophages are a cell in your immune system which work to protect the body. This covers the objective “ Describe the various WBC and their function” from unit 10. Macrophages are derived from monocytes, meaning that the monocytes mature into macrophages only when leaving the circulation and going into the tissue (Lendeckel et al., 2022). Although macrophages are very important to keeping the body free from pathogens, they only make up 2-8% of WBCs (Lendeckel et al., 2022). There are many kinds of WBC in the immune system, a  nd this cell is phagocytic, meaning that it engulfs pathogens and other antigens that would cause the body harm, and has a system to kill the pathogen (Pidwill et al., 2020). It is also part of the innate immune system, meaning that it is the first line of defense against pathogens when they enter the body (Lendeckel et al., 2022). To kill the pathogen, the macrophage must first engulf the pathogen. To accomplish that, the outside of the macrophage cell binds to a pathogen, and creates an endosome (sack) around the pathogen to then bring it inside the macrophage (Lendeckel et al., 2022). Inside the macrophage, there are sacks of membrane-bound organelles called lysosomes which are “abundant in hydrolytic enzymes such as proteases, sulfatases, nucleases, lipases, phosphatases, glycosidases and nucleases, all of which degrade complex macromolecules” (Trivedi et al., 2020) which enable it to break down pretty much any pathogen down to just its components. To get to the pathogen to break it down, the lysosome fuses with the pathogen-containing-endosome and spills all its hydrolytic-enzyme contents into the endosome (Lendeckel et al., 2022). With all kinds of the digestive hydrolytic-enzymes around the pathogen, it makes quick work of tearing it apart and making it unable to harm the body. This whole process is called phagocytosis After it destroys the pathogen, it is able to get other cells to recognize the pathogen by presenting the antigens of the phagocytosed pathogen (Pidwill et al., 2020) so that other immune cells know what to look for to destroy. 

For the art piece of the STEAM project, I choose to make a comic strip. The comic strip goes over phagocytosis so that it is easy to visualize how it works. It starts out with the“sheriff” of the body, because macrophages are one of the first lines of defense against “bad guys” in the body. The macrophage spots a pathogen and questions it for a second (such as trying to see if a receptor fits the pathogen) and determines that the pathogen is indeed a pathogen. It then goes after the pathogen and scoops it into its cell body by forming an endosome around the pathogen. Inside the cell, a lysosome, filled with bad-guy killing stuff (hydrolytic-digestive enzymes) fuse with the endosome and kills the pathogen. The comic strip ends with the macrophage being proud of its work, creating “another safe day in the body”. I used colors to make it easy for the reader to visualize what is going on and to visually understand the whole process of phagocytosis. 

Works Cited

Lendeckel, U., Venz, S., & Wolke, C. (2022, March 10). Macrophages: Shapes and functions. Chemtexts.

Pidwill, G. R., Gibson, J. F., Cole, J., Renshaw, S. A., & Foster, S. J. (2020, December 2). The role of macrophages in Staphylococcus aureus infection. Frontiers.

Trivedi, P. C., Bartlett, J. J., & Pulinilkunnil, T. (2020, May 4). Lysosomal Biology and function: Modern view of cellular debris bin. Cells. 

One Comment

  1. Akela’s project explains how macrophages, a type of immune cell, protect the body from harmful pathogens through a process called phagocytosis. When a pathogen enters the body, macrophages engulf it, forming a protective sac called an endosome. Inside the macrophage, sacs filled with enzymes break down the pathogen into harmless parts. The macrophage then presents these parts to other immune cells as a warning signal, helping the immune system recognize and destroy the pathogen.

    To help people understand this process better, the writer created a comic strip for a project. The comic strip depicts macrophages as “sheriffs” of the body; spotting, swallowing, and breaking down pathogens. It shows how the pathogen is fused with an endosome and then broken down by a lysosome. The use of colors in the comic strip helps make the process of phagocytosis very visually pleasing and easy to understand.

    “The layout is put together extremely well and it is super informative without putting too many words in the strip. Great Job!” – Sean

    Sean Thies

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