Emphasize that we are talking about the "Acquired Immune
Response" antigen -- any agent (molecule) that binds to
components of the immune response -- lymphocytes and their
receptors -- antibodies and the immunogen -- any agent capable
of inducing an immune response. This distinction is probably
most clear when discussing the situation of a hapten and its
carrier. hapten -- is antigenic but not immunogenic unless it is
attached to a carrier molecule of some sort which supplies the
immunogenicity. Requirements for Immunogenicity: Foreignness --
note the example of the rabbit immunized with its own serum
albumin vs. the rabbit immunized with guinea pig serum albumin.
How do you prove that the rabbit unable to respond to its own
albumin is still immunocompetent? Note also that it is possible
for self "antigens" to be immunogenic. Thus the foreignness
requirement can be overcome. When this happens it results in
autoimmunity. High Molecular Weight -- note that these are
general categories and that there are some ex