What is the ultimate goal for all three complement pathways?

The ultimate goal of all three complement pathways—classical, lectin, and alternative—is to enhance the immune response by leading to the destruction of pathogens. This is primarily achieved through the formation of the Membrane Attack Complex (MAC), which directly lyses the target pathogens' membranes.

The formation of the MAC is a critical endpoint in the complement cascade, as it creates pores in the membranes of pathogens, causing cell lysis and death. While the complement system also promotes inflammation and assists in opsonization (marking pathogens for phagocytosis), the direct destruction of pathogens via the MAC represents a crucial mechanism of action for the complement system.

In contrast, while activation of immune cells and production of antibodies are important aspects of the immune response, they are not the direct endpoint of the complement pathways themselves. Instead, these processes are more about enhancing the immune response broadly rather than achieving a specific goal of pathogen destruction through the MAC.