The body usually forms antibodies in response to invasion by a foreign material.
An antibody is a substance formed by the body in response to a perceived foreign substance. Antibodies are produced by the immune system to help identify and neutralize potentially harmful invaders, such as bacteria and viruses.
If it can be harmful, it can be referred to as pathogen.
An antigen is a substance that produces an immune response in the body, typically by binding to specific antibodies or activating immune cells. This immune response is essential for recognizing and eliminating foreign substances such as pathogens.
Depending on the exact response, the substance is generally called a pathogen, yet more specifically depending on the nature of the response and origin of the substance, could be an antigen, allergen, carcinogen, etc.
pathogen
Immune System
A response of the body to an invasion of foreign substances is inflammation. The immune system will also produce more white blood cells and send them to the site of the infection.
Antigenan·ti·gen/ˈantijən/Noun:A toxin or other foreign substance that induces an immune response in the body, esp. the production of antibodies.
An antibody is a substance formed by the body in response to a perceived foreign substance. Antibodies are produced by the immune system to help identify and neutralize potentially harmful invaders, such as bacteria and viruses.
Antigen
An antigen is a substance that triggers an immune response in the body, by stimulating the production of antibodies. This response helps the body to recognize and destroy harmful pathogens such as bacteria, viruses, or foreign substances.
If it can be harmful, it can be referred to as pathogen.
A foreign substance is a substance that doesn't belong somewhere. A piece of glass or splinter is a foreign substance that people get in their body.
a toxin or other foreign substance that induces an immune response in the body, especially the production of antibodies.
Antigen
A foreign molecule is a substance that is not naturally produced or recognized by the body. When foreign molecules enter the body, the immune system may identify them as threats and initiate an immune response to protect the body from potential harm.
A foreign substance is a substance that doesn't belong somewhere. A piece of glass or splinter is a foreign substance that people get in their body.