Are red blood cells considered part of the immune system?

Red blood cells, also known as erythrocytes, primarily function to transport oxygen from the lungs to the body's tissues and carry carbon dioxide back to the lungs for exhalation. They do not play a direct role in the immune response, which is primarily facilitated by white blood cells, lymphocytes, macrophages, and other components of the immune system.

While red blood cells can have some indirect interactions with the immune system (for example, by influencing the environment in which immune cells operate), they lack the specific functions associated with immune cells, such as identifying, attacking, or remembering pathogens. This distinction is crucial for understanding the roles of different cell types in the body and emphasizes the specialized nature of immune response mechanisms. Therefore, categorizing red blood cells as part of the immune system is not accurate.