| Antibodies structure | - Proteins synthesised by B cells
- Heavy and light chains
- Variable + constant regions
- Made up of 4 polypeptide chains |
| Variable region | - The binding site is different on different antibodies |
| Constant region | - The rest of the antibody |
| Antigen-Antibody Complex | - Formed when antigens bind to a specific site on antibody |
| Complementary Shape | - Antigens have a specific shape that fits/binds into specific site |
| Function of antibody | - Do not destroy antigen
- Prepares antigen for destruction |
| How antibody leads to the destruction of antigen e.g. bacteria | - Agglutination, clumps bacteria cells
- Making it easier for phagocytes to locate them
- They serve as markers that stimulate phagocytes to engulf bacterial cells to which they are attached |
| Agglutination | - Clumping pathogens together |
| Antitoxins | - Neutralises toxins |
| Lysis | - Digests the membrane, killing pathogen |
| Opsonisation | - Coating pathogen in protein to identify them as foreign |
| Monoclonal Antibodies | - Isolation and cloning of a single type of antibody
- Formed by the fusion of a B cell with a tumour cell |
| Targeting medication to specific cell types by attaching therapeutic drug to antibody | - Monoclonal antibodies specific to antigen cancer cells
- Antibodies are given to a patient
- Attach to surface of cancer cells
- Blocks the chemical signals that stimulate their uncontrollable growth |
| Medical diagnosis | - Monoclonal antibodies used for diagnosis of influenza, hepatitis and chlamydia
- Certain cancers like prostate cancer |
| Pregnancy testing | - Placenta produces a hormone called hCG
- Found in mothers urine
- Monoclonal antibodies present on test strip
- hCG binds to antibodies
- hCG-antibody-complex moves along strip
- Until trapped by different type of antibody creating coloured line |
| Ethical use of monoclonal antibodies | - Involves inducing cancer in mice
- Some deaths associated with use
- Testing for safety of new drugs is dangerous e.g. organ failure |
