Final answer:
Antibodies eradicate infections through neutralization, which blocks pathogens from infecting host cells; opsonization, which tags them for destruction by phagocytes; and complement activation, which destroys the pathogen's cell membrane.
Step-by-step explanation:
Three Mechanisms of Antibody Action to Eradicate Infection
Antibodies play a vital role in the immune system by identifying and neutralizing pathogens. They utilize various mechanisms to protect the body from infection. Here are three distinct mechanisms by which antibodies can eradicate infections:
- Neutralization: Antibodies neutralize pathogens by binding to crucial sites that are necessary for the pathogen to infect host cells, such as surface receptors. This action prevents the pathogen from docking on host cells, effectively stopping the infection before it can start.
- Opsonization: In this process, antibodies tag pathogens for destruction. When antibodies coat a pathogen, they signal to phagocytic cells, like macrophages and neutrophils, to engulf and destroy the tagged microbe.
- Complement Activation: Antibodies can activate the complement system, which is a series of proteins that work in concert to lyse pathogens. This can lead to the destruction of the pathogen's cell membrane, ultimately resulting in its elimination.
These mechanisms ensure that extracellular pathogens are effectively managed by the immune system, which either directly impedes their ability to infect or labels them for destruction by other immune cells. The spleen then filters these neutralized pathogens from the body, and they are eliminated through urine or feces.