U4 AOS1 Topic 8: Immunotherapy
Immunotherapy
is the treatment of a disease done by modifying the immune system.
Immunotherapy can be categorized as:
1. Activation immunotherapy
which enhances the immune response.
2. Suppression immunotherapy
which reduces the immune response.
Examples
of Immunotherapy
Following
are the examples of immunotherapy:
1. Dendritic
cell therapy involves the tumor-associated antigens to be presented by antigen
presenting cells known as dendritic cells so that all cancer cells in the body
can be targeted.
2. CAR-T
therapy involves the formation of chimeric antigen receptor T cells. This is
done by introducing the gene coding for antigen receptor into the DNA of T
cells to modify these cells. This gene will be expressed in T cells and antigen
receptor proteins are displayed on cell membrane to bind to specific antigen
and recognize the cancer cells.
3. Antibody
therapy involves the formation of antibodies such as monoclonal antibodies
which help in treatment of diseases.
4. Cytokine
therapy involves the use of cytokines which are signaling molecules in immune
systems. These signaling molecules help to modify the immune response.
Monoclonal antibodies
Monoclonal
antibodies are prepared in laboratories and can bind to only one specific
antigen. Due to this specificity, monoclonal antibodies are used to treat specific
diseases such as cancer.
Production
of monoclonal antibodies
Monoclonal
antibodies can be produced by following these steps:
1. Identification
of disease-causing cells and isolation of antigens present on these cells.
2. Vaccinating
these antigens into an animal such as mice to induce an immune response. This
immune response results in the formation of B lymphocytes which are specific to
these antigens.
3. Extraction
of B lymphocytes from the spleen of mice.
4. Fusion
of extracted B lymphocytes with myeloma cells (which are cancerous human plasma
cells) to produce hybridoma cells.
5. Screening
of hybridoma cells for the selection of cells with specific antibodies. Hybridoma
cells are cloned to produce a large number of antibodies.
6. Collection
and purification of antibodies.