monoclonal antibodies

antibodies

proteins produced by a type of white blood cell called lymphocytes

how do lymphocytes produce antibodies

pathogens have proteins on they surface called antigens

when a pathogen infects the body, lymphocytes recognise these antigens as foreign

so they attack them by producing antibodies

monoclonal antibodies

antibodies from a single clone of cells

what are antibodies specific to

one binding site on one protein antigen and so are able to target a specific chemical or specific cell in the body

where are monoclonal antibodies made

laboratory

how do we produce monoclonal antibodies

• inject a mouse with the antigen we want our antibody to bind to

• this stimulates lymphocytes in mouse that make antibodies specific to antigen

• spleen cells that produce lymphocytes are removed

• can take spleen cell and combine with tumour cell to create hyrbidoma

• hybridoma divides and produces millions of monoclonal antibodies specific to original antigen

how do we speed up division of lymphocyte clones

combine with fast dividing tumour cells to create hybridoma

hybridoma

divides rapidly

produces lots of identical cells that all produce same antibodies

where do we leave hybridoma to replicate

Petri dish

large amount of identical antibodies can be collected and purified

uses of monoclonal antibodies

• pregnancy tests

• measure levels of chemicals in blood

• treat diseases like cancer

• to locate specific molecules

what can we attach to the bottom of monoclonal antibodies

drugs

fluorescent proteins

radioactive material

monoclonal antibodies use in pregnancy tests

-bind with hormone HCG found in urine of pregnant women

-monoclonal antibodies re attached to end of stick where urine goes

-if HCG present, it will bind to change colour of test

how are monoclonal antibodies used to treat cancer

• if we had monoclonal antibodies that were specific to antigens on cancer cells

• we could locate and destroy cancer by attaching drugs or radioactive material to Monoclonal antibody and then injecting into patient

• as they would locate cancer cells and destroy them

benefits of monoclonal antibodies

-can treat conditions, test for hormones, test for diseases

-can be produced quickly

limitations to monoclonal antibodies

result in unwanted side effects so they are not as widely used by doctors as orginaly have thought

ethical issues with monoclonal antibodies

injecting mouse-disagreement on use of animals