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.
Immune System
When the body detects a foreign substance, such as a pathogen or allergen, the immune system is activated. This typically involves the production of antibodies to target and neutralize the invader, as well as the recruitment of immune cells to help eliminate the threat. Inflammatory responses like swelling, redness, and fever may also occur as the body works to fight off the foreign substance.
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.