Clonal selection theory in immunology is a scientific theory, which states about the functioning of lymphocytes of body immune system in response to foreign antigen. This theory provide illustration about the diversity of antibodies that formed during the immune responses.
The clonal selection theory is presented by doctor frank macfarlane burnet on work of Jerne and Talmadge in 1957. According to this theory, the foreign antigen when invade in body it only activates the specific cells that induced to divide for the formation of antibody.
Earlier work
In 1900, side chain theory is proposed by Paul Ehrlich. According to this theory the cells have different side chains on their surface which are able to react with antigen. When an antigen invade…show more content… But it has no impact on precursors for the anti-BGG response. Because the anti-BGG precursors are different from antiFla antibody-forming cells which is due to their ability to specifically bind the antigen to their surface. It provides key element for Burnet's Clonal Selection Theory.
• 3H-TdR Suicide
In 1966, Mishell and Dutton developed a system in which they could form an in vitro primary antibody response. They incubated normal mouse spleen cells with antigen under controlled conditions and after five days there is presence of large numbers of antibody-forming cells in the culture dish.
Highly radioactive tritium-labeled thymidine (3H-TdR) is used to kill cells that undergoes proliferation. During 24-hour periods it is treated with hot thymidine then precursors of antibody forming cells were proliferating. A 3H-TdR pulse between 24 and 48 hours should eliminate exposure to original SRBC. However, if AFCPs are not pre-exposed, then it does not show response to a second dose of SRBC, and it also have no response to a different antigen given at the same time.
This show that the precursor cells that proliferate in a specific response to antigenic exposures for the closely related antigens SRBC and BRBC are…show more content… These are B-cells which are joined together for synthesis and secretion of an antibody.
• Pool of memory cells which are also B lymphocytes that have receptors of the same specificity that are at the original activated B cell. Immunological Memory and the Secondary Response
The foreign antigen that invade in body cause infection after recovering from an infection the concentration of antibodies against that infectious foreign agent starts to gradually decrease which takes weeks, months and years. Then a time may come when antibodies against that foreign agent can no longer be detected. The individual often is still protected against that disease as person is still immune. When there is a second exposure to the foreign agent usually calls forth a more rapid and larger response to the antigen. This is called the secondary