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POLYCLONAL
ANTIBODIES
Polyclonal Antibody
| Representative Examples: | Antithymocyte globulin-equine (Atgam®), Antithymocyte globulin-rabbit (RATG, Thymoglobulin®) |
| Clinical Use: | Early rejection prophylaxis, treatment of rejection. |
| General Mechanism: | Polyclonal antibodies are directed against lymphocyte antigens but instead of the single-specificity of the monoclonal antibodies, these anitlymphocyte antibodies are directed against multiple epitopes. The agents are used in induction therapy and can be given to avoid the nephrotoxic effects of calcineurin inhibitors and to postpone or avert refection of the allograft. |
Antithymocyte globulin-equine and Antithymocyte globulin-rabbit
| Pharmacological Mechanism: | Antithymocyte globulin is a polyclonal antibody derived from either horses (Atgam®) or rabbits (Thymoglobulin®). The agents contain antibodies specific for many common T cell antigens including CD2, CD3, CD4, CD8, CD11a, CD18. The antithymocyte globulin binds lymphocytes that display the surface antigens previously listed. This effectively depletes T-cell concentration in the body through complement-dependent cytolysis and cell mediated opsonization (define in rejection portion or glossary) following with T cell clearance from the circulation by the reticuloendothelial system (RES). |
| Side Effects: |
Side effects observed with Antithymocyte globulin use include:
|
| Representative Dose/Route: | Antitthymocyte globulin can be a part of the induction therapy or acute rejection treatment. The recommended dose of Atgam® is 10-20 mg/kg/day administered daily through and IV for up to 14 days. The recommended dose of Thymoglobulin® is 1.5mg/kg adiminstered daily through an IV for 7-14 days. |
| Drawbacks: | Drawbacks from using these polyclonal antibodies include unpredictability, variable efficacy and adverse reactions (increased risk of infections, lympho-proliferative disease due to over-immunosupression - this is not specific) |
Corticosteriods Calcineurine Inhibitors Antiproliferative Agents Monoclonal Antibodies Polyclonal Antibodies
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Side Effects Drug Efficacy