Antigen
an·ti·gen/ˈantijən/Noun:A toxin or other foreign substance that induces an immune response in the body, esp. the production of antibodies.antigens
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 pathogen is an organism or substance that invades the body and causes damage to cells or tissues, leading to illness or infection. Examples of pathogens include bacteria, viruses, fungi, and parasites.
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.
Antigen
Prions are the proteins which invades organisms.. they are usually proteinaceous material devoid of nucleic acid but yet capable of producing diseases in humans and other animals..examples are scrapie, kuru, etc..
pathogen
antigen- any substance the body regards as foreign
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.
A heterologous protein; however, any abnormal substance (bacteria, viruses, cancer cells) in the body is called an antigen
A foreign substance is any material that is not naturally present in a certain environment or body. It can come from outside sources and may cause harm, contamination, or interference with normal processes.
If it can be harmful, it can be referred to as pathogen.