- Immunosuppressive agents are those that suppress immune response.
- They are used in transplantation surgery and in situations that require suppression of host immunity.
The agents are as follows:
- Radiometric drugs
- Antilymphocyte serum
- Sublethal dose of irradiation is toxic to replicating cells and is used to suppress antibody formation.
- Antibody production ceases after 24 hours of receiving irradiation.
- These include alkylating agents (such as cyclophosphamide, nitrogen mustard, etc.), which suppress antibody production.
- Cyclophosphamide, given for 3 days, completely suppresses the antibody response.
- It selectively prevents replication of B cells.
- Corticosteroids are anti-inflammatory drugs that diminish the responsiveness of both B and T cells.
- They alter maturation of activated cells by suppressing the production of interleukins.
- They suppress delayed hypersensitivity, but in therapeutic doses for a short period, they have little effect on the production of antibodies.
- These include folic acid antagonists (such as methotrexate); analogs of purine (6-mercaptopurine and azathioprine); and analogs of cytosine (cytosine arabinose); and uracil (5-fluorouracil).
- These substances inhibit DNA and RNA synthesis, thereby inhibiting the cell division and differentiation, which is essential for cellular and humoral immune responses.
- These are usually used for prevention of graft rejection.
- Antilymphocyte serum (ALS) is a heterogeneous antiserum raised against T lymphocytes.
- The ALS acts mainly against circulating lymphocytes but not against lymphocytes in lymphoid organs.
- It is mainly used to prevent graft rejection in transplantation surgery.