Antibodies serve as an important component of the immune system, using diverse mechanisms to destroy pathogens. Antibodies secreted by plasma cells play a crucial role in combating extracellular pathogens and toxins. They do not always kill pathogens directly but neutralise, block, tag, or help destroy them through several mechanisms.
Mechanisms by Which Antibodies Destroy Pathogens
Given below are the steps by which antibodies destroy pathogens:
Steps by Which Antibodies Destroy Pathogens | Description |
|---|---|
1. Neutralisation | Antibodies bind to the surface proteins of pathogens or toxins and block other attachment sites of pathogens. |
2. Opsonisation | Antibodies attach to the pathogen and tag it, and this makes it easier for like macrophages and neutrophils to recognise and engulf it. |
3. Agglutination | Antibodies have two antigen-binding sites, and they bind to multiple pathogens at once and causing pathogens to clump together. |
4. Complement Activation | Some antibodies activate the complement system, and this forms a structure called MAC (Membrane Attack Complex). MAC creates holes in the pathogen's membrane, and the pathogen bursts and dies. |
5. Antibody-Dependent Cell-Mediated Cytotoxicity (ADCC) | Natural Killer (NK) cells recognise these antibodies, and NK cells release toxic chemicals to destroy the abnormal cell. |