Active Immunity
Active immunity develops as a result of the contact of an individual with pathogenic
organisms or their products. They stimulate the body to produce antibodies in response to
the antigens. The immunity thus produced is specific for a particular disease.
Passive Immunity
Passive immunity is produced when antibodies formed in one human being are
transferred to another non-immune individual. Passive immunity is rapidly established
but lasts for a short while.
Natural Immunity
Immunity due to infection:
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Natural active: Occurs during infection. It is active because lymphocytes are activated by
antigens on pathogen's surface.
Natural passive: Mother to child through placenta or milk.
Artificial Immunity
Immunity due to inoculation with vaccine:
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Artificial active: Injecting or taking antigens by mouth. Takes time for T and B cells to be
activated but gives long lasting immunity.
Artificial passive: Used during potentially fatal diseases. Provides an instant response
but only temporary as antibodies are not the body's own so memory cells are not
created. E.g. tetanus - injection of antitoxins given.
"Active and Passive Immunity." TutorVista. 2008. Web. 2 Oct. 2009.
<http://www.tutorvista.com/content/biology/biology-iv/immune-system/activeand-passive-immunity.php>.
Burrell, John. "Topic 11.1 Defense Against Infectious Diseases." Click4Biology. Web. 2
Oct. 2009. <http://www.click4biology.info/c4b/11/hum11.1.htm#2>.
Describe the production of monoclonal antibodies and their use in diagnosis and
treatment.
When an immune response occurs, antibodies specific to the pathogen are produced. We
can make use of this in medicine and biotechnology-by producing large numbers of
antibodies in the laboratory to be used therapeutically or diagnostically.
Whereas an immune response may be polyclonal (a B-cell could respond to multiple
antigens or epitopes), for this purpose we must have a monoculture- monoclonal
antibodies.
1. Immune response is stimulated using the antigen
2. Specific B-cells are harvested
3. B-cell is fused with a myeloma (tumour) cell
4. Hydridoma makes a large number of clones
5. Clones produce antibodies, which are collected
Uses of monoclonal antibodies
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Antibodies are used in diagnostic tests to detect small amounts of drugs, toxins or
hormones. Other diagnostic used to diagnosis of AIDS by ELISA test.
Other is used in te radioimmunodetection and radioimmunotherapy of cancer for
targeting cancerous cells. Example is Rtoxin.
Monoclonal antibodies can be used to identify and to trace specific cellsor
molecules in an organism. It can find out which proteins are responsible for cell
differentiation in the respiratory system
OKT3 is an antibody to T3 Antigen of T cells and is used to alleviate the problem
of organ rejection in patients who have had organ trasplnats.
"Monoclonal Antibodies." Biology @ Davidson. Web. 07 Oct. 2009.
<http://www.bio.davidson.edu/Courses/molbio/MolStudents/01rakarnik/mab.html>.