The main difference between antigen and pathogen is that antigen is a molecule that can trigger an immune response while a pathogen is a microorganism that causes diseases. Pathogens can be bacteria, viruses, or other microorganisms. An antigen can be a protein, polysaccharide, or lipid on the surface of a pathogen. Antigens present on pathogens are called exogenous antigens.
What is an antigen?
An antigen refers to any substance that the body recognizes as foreign and triggers an immune response. Antigens can be proteins, polysaccharides, lipids, or nucleic acids. An epitope or antigen determinant is the part of an antigen that is bound by an antibody.
An antibody is a glycoprotein molecule produced in response to a specific antigen. Antibodies are produced by plasma cells in the blood after identifying a foreign substance in the body. The four main types of antigens are exogenous antigens, endogenous antigens, autoantigens, and neoantigens.
What is a pathogen?
A pathogen refers to an agent that causes disease or illness in the host. Pathogens can be microorganisms such as bacteria, viruses, fungi, protozoa, algae, and parasites. Normally, microorganisms can be found in or on the human body. These microorganisms do not usually cause any disease. They are called natural flora.
The natural flora lives on the skin, in the mouth, in the intestine, or in the vagina. However, there is another type of microorganisms that can cause diseases and illnesses to the host. They are called pathogens.
In general, pathogens are recognized by the host’s immune system through the identification of various antigens on the surface of the pathogens. Recognition of a foreign antigen triggers an immune response that destroys the pathogen.
Antibodies are produced in response to a specific pathogen in the body, and these antibodies bind to specific antigens to neutralize it. Antibody binding to the pathogen can immobilize the pathogen or lyse the pathogen by allowing phagocytic cells to recognize it in the immune system.
Pathogens can also be destroyed by complement reactions by binding complement proteins to the pathogen.
Similarities Between Pathogen and Antigen
- Both the antigen and the pathogen trigger an immune response in the host.
- Both the antigen and the pathogen can be considered immunogenic.
- Both antigen and pathogen can cause diseases in the host.
Difference Between Antigen and Pathogen
An antigen is a molecule capable of inducing an immune response in the host organism while A pathogen is an agent that can cause disease or illness in the host.
Antigens can be a molecule on the surface of the pathogen, triggering an immune response while The pathogen can cause disease.
Antigens can be proteins, polysaccharides, lipids, or nucleic acids while Pathogens are organisms.
Antigens can be exogenous antigens, endogenous antigens, autoantigens, or neoantigens while the Pathogens can be bacteria, viruses, fungi, protozoa, or parasites.
Conclusion: Antigen Vs Pathogen
Antigen & pathogen are two types of immunogens that can trigger an immune response in host organisms. An antigen refers to a substance that triggers an immune response in a host. The antigens can be proteins, polysaccharides, or lipids. They are sometimes present on the surface of pathogens invading the host. A pathogen is a disease-causing agent for the host. Pathogens are organisms, while antigens are molecules. Therefore, the main difference between antigen and pathogen is the level of organization of each immunogen.
Read more:
- Antigen and its Types
- Pathogen and its types