Antibodies and monoclonal antibodies
| English | Chinese | Pinyin |
|---|---|---|
| antibody | 抗体 | kàng tǐ |
| antigen-binding site | 抗原结合位点 | kàng yuán jié hé wèi diǎn |
| variable region | 可变区 | kě biàn qū |
| monoclonal antibody | 单克隆抗体 | dān kè lóng kàng tǐ |
| hybridoma | 杂交瘤 | zá jiāo liú |
Custom-made weapons
- An antibody 抗体 is a Y-shaped protein made by plasma cells.
- Each one fits one antigen exactly — like a lock and key.
- We can even mass-produce a single type for medicine.
Monoclonal antibodies are:
Monoclonal = "one clone" — all identical, so they all bind the same target.
Antibody structure and action
- The two tips of the Y are the antigen-binding sites 抗原结合位点.
- Each site has a variable region 可变区 — a special shape that fits one antigen only.
- Antibodies help by: sticking to antigens, clumping pathogens together, marking them for phagocytes, and blocking toxins.
A Y-shaped antibody with two antigen-binding sites
Inside an antibody
Tap each part. The variable tips bind one specific antigen; the constant stem is the same in every antibody.
The variable region of an antibody:
The two tips of the Y are variable regions — each shaped to bind one specific antigen.
Select all the ways antibodies help destroy pathogens.
Antibodies agglutinate pathogens, mark them for phagocytes and neutralise toxins — they do not build cell walls.
Match each term to its meaning.
The variable tip is specific; the constant stem calls phagocytes; agglutination clumps; monoclonal = all identical.
Monoclonal antibodies
- A monoclonal antibody 单克隆抗体 is a single, identical type of antibody, made by the hybridoma 杂交瘤 method:
- an animal is given an antigen, so it makes B-lymphocytes that produce the wanted antibody.
- those B-lymphocytes are fused with tumour cells (which divide endlessly).
- the fused hybridoma both makes the antibody and divides without stopping.
Making monoclonal antibodies with a hybridoma
A hybridoma is made by:
The B-lymphocyte supplies the wanted antibody; the tumour cell makes it divide endlessly — together a hybridoma.
A B-lymphocyte fused with a tumour cell, so it both makes antibody and divides endlessly, is a ______.
The hybridoma is cloned to mass-produce one (monoclonal) antibody.
What they're used for
- diagnosis — detecting a specific molecule (e.g. a pregnancy test).
- treatment — carrying drugs to specific target cells, such as cancer cells.
Monoclonal antibodies are used in:
They detect specific molecules for diagnosis, and can carry drugs to specific target cells for treatment.
You've got it
- an antibody is Y-shaped; the tips are variable regions that bind one antigen
- antibodies clump, mark, and block toxins so pathogens are dealt with
- monoclonal = one identical antibody, made by a hybridoma (B-lymphocyte + tumour cell)
- used in diagnosis (pregnancy test) and treatment (target drugs to cancer cells)