How does cytolysis occur via the complement pathway?

• A. Formation of the membrane attack complex (MAC) that creates pores in the target cell membrane
• B. Activation of phagocytes to engulf and digest pathogens
• C. Stimulation of B cells to produce more immunoglobulins
• D. Release of antibodies that neutralize toxins

Answer: (A)

Verified step by step guidance

1. Understand that the complement pathway is part of the innate immune system and involves a series of proteins that enhance the ability to clear pathogens.
2. Recognize that cytolysis refers to the destruction of a target cell by disrupting its membrane integrity.
3. Identify that the complement pathway leads to the formation of the Membrane Attack Complex (MAC), which is a structure composed of complement proteins that assemble on the surface of the target cell membrane.
4. Know that the MAC creates pores or channels in the target cell membrane, causing an influx of water and ions, which ultimately leads to cell swelling and bursting (cytolysis).
5. Distinguish this mechanism from other complement functions such as activation of phagocytes, stimulation of B cells, or antibody release, which do not directly cause cytolysis.