No new information in Greencastle woman's disappearance. No new information in Greencastle woman's disappearanceThere was still no word Tuesday night on the whereabouts of Julie McCutcheon, the Greencastle woman who went missing a week ago while house-sitting for a friend in Gettysburg.
Medical Definition of ANTIGEN. : any substance (as an immunogen or a hapten) foreign to the body that evokes an immune response either alone or after forming a complex with a larger molecule (as a protein) and that is capable of binding with a product (as an antibody or T cell) of the immune response.â anÂ·tiÂ·genÂ·ic \Ëan-ti-Ëje-nik\ adjective.edical Definition of ANTIGEN. : any substance (as an immunogen or a hapten) foreign to the body that evokes an immune response either alone or after forming a complex with a larger molecule (as a protein) and that is capable of binding with a product (as an antibody or T cell) of the immune response.
Any substance capable of generating such a response is called an antigen, or immunogen. Antigens are not the foreign microorganisms and tissues themselves; they are substances --- such as toxins or enzymes --- in the microorganisms or tissues that the immune system considers foreign.