Zusammenfassung der Ressource
Pack 6 Cell recognition
and the immune system
Part 2
- Monoclonal antibodies
- Antibodies that are produced
by a single clone of B cells
- Method:
- 1. Mice are injected by non-self
material against which an antibody
is required
- 2. B cells in the mouse produce a mixture of
antibodies, these B cells are extracted from the
spleen of the mouse
- 3. B cells are fused with cells that last a long time (a bone cancer cell is used)
- 4. Fused cells (hybridomas) are grown individually in tissue cultures
- 5. Any clone producing the correct antibody is grown on a large scale
- Uses:
- Targeting medication
- Direct monoclonal antibody therapy
- A monoclonal antibody is produced that is specific to an antigen
- Antibodies are given to the patient and attach to the receptors on (for example) a cancer cell
- The attachment blocks chemical signals that stimulate uncontrolled growth
- Indirect monoclonal antibody therapy
- Same as direct but adds a
radioactive or cytotoxic drug
to kill the cell
- Medical diagnosis
- ELISA:
- 1. Test sample antigens are attached to a well in a test dish
- 2. Unattached antigens are washed off
- This will stop antibodies
attaching to any unattached
antigens
- 3. Antibody to the antigen to be detected is added
- 4. Excess antibody is washed off
- If they aren't bound but
still in the sample you will
get a false positive result
- 5. A second antibody that only binds with the first and has an enzyme attached is added
- 6. Excess antibody is washed off
- 7. Colourless substrate to the enzyme is added
- 8. the enzyme will act on the substrate to form a coloured product if present
- HIV
- HIV directly attacks cells such
as T helper cells that have a
protein called CD4 on their
surface
- HIV infected cells die after released the
replicated virus which then infect other T
helper cells
- This means B cells won't be stimulated to
produce antibodies