antibodies in medecine

• what is a monoclonal antibody?

  antibodies produced by a single clone of cells
• monoclonal antibodies uses:

  • target medication to specific cell types by attaching a therapeutic drug to an antibody (radioimmunotherapy)
  • pregnancy testing
  • medical diagnosis by identifying proteins or antigen presence using the ELISA test
• radioimmunotherapy links radioactive atoms to monoclonal antibodies that deliver the radioactivity by seeking out and latching onto proteins found on the cancer cells
• Pregnancy tests:

  • antibodies complimentary to hCG protein are bound to a coloured bead
  • hCG in urine binds to antibodies
  • urine moves up to the strip carrying beads
  • immoblised antibodies which bind to hCG create first blue line
  • immobilised antibodies which bind to coloured beads create second blue line if hCG is present
• An ELISA test can be used to test for the presence of any antigen or antibody
• direct ELISA test involves just one antibody binding to an antigen ( testing for a specific antigen)
• indirect ELISA test uses multiple antibodies to detect specific antibodies in a serum sample
• indirect ELISAs can be more sensitive than direct detection methods, but are more time consuming and there is a chance of cross-reactivity with the antigen
• antibiotics are ineffective against viruses because they inhibit bacterial metabolic functions like:

  • cell wall synthesis
  • DNA replication
  • protein synthesis
  • viruses don't have these functions
• • B lymphocytes don't divide but make specific antibodies so they combine with tumour cells that don't make antibodies but divide ( hybridoma cells)
  • hybridoma cells are cloned
  • hybridoma cells produce the monoclonal antibodies which are then separated, purified and then used
• a retrovirus contains RNA and reverse transcriptase which enables the virus to produce DNA from RNA