| Antigen | Antibody | |
| Overview | Substance that can induce an immune response | Proteins that recognize and bind to antigens |
| Molecule type | Usually proteins, may also be polysaccharides, lipids or nucleic acids | Proteins |
| Origin | Within the body or externally | Within the body |
| Image |  |  |
The Role of Antigens & Antibodies in Vaccinations
Vaccines contain antigens which stimulate the B lymphocytes of the immune system to respond by producing plasma cells which secrete disease specific antibodies (Primary response). Some of the B cells become memory B cells, which will recognise future exposure to the disease. This results in a faster and more intense production of antibodies, which effectively work to eliminate the disease by binding to the antigens (Secondary response).
BPCS Notes brings Prelims and Mains programs for BPCS Prelims and BPCS Mains Exam preparation. Various Programs initiated by BPCS Notes are as follows:-