| Antigens | antibodies |
| It is chemical factors or agent which can induce immune system to produce antibodies. | It is special protein molecules synthesized by immune system of body for fighting with antigens. |
| They can cause disease which may be viral, bacterial etc. | They protect from diseases and pathogens. |
| They stimulate immune system. | They response with antigens. |
| It may be chemical like polysaccharide, living organisms, particles, part of organisms of any factor. | It is always protein having relatively low molecular weight. |
| They are commonly called Immunogens. | They are commonly called immunoglobulins. |
| Each antigen actives for specific antibodies. | It is specific with antigen. |
| Usually they are dangerous for organisms. | Usually they are non- dangerous and protective in nature. |
