Immunosuppressive therapy cyclosporine

Nonspecific immunosuppressive therapy in an adult patient is usually through cyclosporin (35), started intravenously at the time of transplantation, and given orally once feeding is tolerated. Typically, methylprednisone is started also at the time of transplantation, then reduced to a maintenance dose. A athioprine (31) may also be used in conjunction with the prednisone to achieve adequate immunosuppression. Whereas the objective of immunosuppression is to protect the transplant, general or excessive immunosuppression may lead to undesirable compHcations, eg, opportunistic infections and potential malignancies. These adverse effects could be avoided if selective immunosuppression could be achieved. Suspected rejection episodes are treated with intravenous corticosteroids. Steroid-resistant rejection may be treated with monoclonal antibodies (78,79) such as Muromonab-CD3, specific for the T3-receptor on human T-ceUs. Alternatively, antithymocyte globulin (ATG) may be used against both B- and T-ceUs. 

Azathioprine was originally approved by the FDA in 1968 as an adjunct immunosuppressant for use in renal transplant recipients. It is available in oral and IV dosage forms.11 Prior to the advent of cyclosporine, the combination of azathioprine and corticosteroids was the mainstay of immunosuppressive therapy. Over the past 10 years, the use of azathioprine has declined markedly due in large part to the success of the MPA derivatives, which are more specific inhibitors of T cell proliferation. 

Sirolimus is currently the only FDA-approved ToR inhibitor. One of its derivatives, everolimus, is in phase III clinical trials and has been approved for use in some European countries.30 Sirolimus is a macrolide antibiotic that has no effect on cal-cineurin phosphatase.11,31,32 Sirolimus inhibits T cell activation and proliferation by binding to and inhibiting the activation of the mammalian ToR, which suppresses cellular response to IL-2 and other cytokines (i.e., IL-4 and IL-15J.11,31 Studies have shown that sirolimus may be used safely and effectively with either cyclosporine or tacrolimus as a replacement for either azathioprine or mycophenolate mofetil.33 However, when using both sirolimus and cyclosporine as part of a patient s immunosuppressant therapy, because of a drug interaction between the two resulting in a marked increase in sirolimus concentrations, it is recommended to separate the sirolimus and cyclosporine doses by at least 4 hours. Sirolimus also can be used as an alternative agent for patients who do not tolerate calcineurin inhibitors due to nephrotoxicity or other adverse events.34... 

Antibodies have and likely will find additional use in transplantation-related medicine. In general, cell-mediated immunological mechanisms are responsible for mediating rejection of transplanted organs. In many instances, transplant patients must be maintained on immunosuppressive drugs (e.g. some steroids and, often, the fungal metabolite cyclosporine). However, complications may arise if a rejection episode is encountered that proves unresponsive to standard immunosuppressive therapy. Orthoclone OKT-3 was the first monoclonal antibody-based product to find application in this regard. 

Only physicians experienced in the management of systemic immunosuppressive therapy for the indicated disease should prescribe cyclosporine. Patients receiving the drug should be managed in facilities equipped and staffed with adequate laboratory and supportive medical resources. The physician responsible for maintenance therapy should have complete information requisite for the follow-up of the patient. 

Carcinogenesis The risk of malignancies in cyclosporine recipients is higher than in the healthy population but similar to that in patients receiving other immunosuppressive therapies. 

Echinacea (Echinacea purpurea) Uses immune system stimulant prevention/Rx of colds, flu as supportive th apy for colds chronic infxns of the resp tract lower urinary tract Action Stimulates phagocytosis cytokine production T resp cellular activity topically exerts anesthetic, antimicrobial, anti-inflammatory effects Efficacy Not established may X severity duration of URI Available forms Caps w/ powdered herb equivalent to 300-500 mg, PO, tid pressed juice 6-9 mL, PO, once/d tine 2-4 mL, PO, tid (1 5 dilution) tea 2 tsp (4 g) of powdered herb in 1 cup of boiling water Noles/SE Fever, taste p -version, urticaria, angioedema Contra w/ autoimmune Dz, collagen Dz, progressive systemic Dz (TB, MS, collagen-vascular disorders), HIV, leukemia, may interfere w/ immunosuppressive therapy Interactions t Risk of disulfiram-like reaction W/ disulfiram, metronidazole T risk of exacerbation of HIV or AIDS W/ chinacea amprenavir, other protease inhibitors X effects OF azathioprine, basiliximab, corticosteroids, cyclosporine, daclizumab, econazole vag cream, muromonab-CD3, mycophenolate, prednisone, tacrolimus EMS Possible immunosuppression... 

The principal advantage of MMF over alternative systemic immunosuppressive agents (e.g., methotrexate, cyclosporine) is its relative lack of hepatotoxicity and nephrotoxicity. Adverse effects produced by MMF most commonly include nausea, abdominal cramps, diarrhea, and possibly an increased incidence of viral and bacterial infections. Whether MMF may be associated with an increased long-term risk of lymphoma or other malignancies is controversial however, any such risk is likely to be lower in patients treated for skin disease with MMF monotherapy than in transplant patients treated with combination immunosuppressive therapy. 

Azathioprine also has applications in certain disorders with autoimmune components, most commonly rheumatoid arthritis. It is as effective as cyclophosphamide in the treatment of Wegener s granulomatosis. It has largely been replaced by cyclosporine in immunosuppressive therapy. Relative to other cytotoxic agents, the better oral absorption of azathioprine is the reason for its more widespread clinical use. 

The introduction of cyclosporin, a peptide derived from a fungus, revolutionised immunosuppressive therapy, and was one of the major influences in the improvement of early graft survival in transplant surgery when introduced in the 1980s. The main action is a relatively selective inhibition of IL-2 production and consequently a decreased proliferation of T cells. A major advantage of cyclosporin is that it does not cause myelosuppression in therapeutic doses. The major side effect is nephrotoxicity, which occurs in about 20% of patients, and about 50% of patients develop moderate hypertension. The other major side effect is hepatotoxicity with cholestasis and hyperbilirubinaemia. 

Immunosuppressive therapy is utilized in chronic severe asthma, where cyclosporine is often effective and sirolimus is another alternative. Omalizumab (anti-IgE antibody) has recently been approved for the treatment of severe asthma (see previous section). Tacrolimus is currently under clinical investigation for the management of autoimmune chronic active hepatitis and of multiple sclerosis, where IFN-3 has a definitive role. 

The antithymocyte globulin (ATG) Fresenius S, produced in rabbits, is an example of a polyclonal antibody mixture used in immunosuppressive therapy in combination with other immunosuppressive agents (e.g., cyclosporine, prednisone) after organ transplantation. 

Haberal M, Emrroglu R, Dalgic A, Karakayli H, Moray G, Bilgin N (2004) The impact of cyclosporine on the development of immunosuppressive therapy. Transplant Proc 36 143S-147S. 

Bennett WM, DeMattos A, Meyer MM, Andoh T, Barry JM. Chronic cyclosporine nephropathy the Achilles heel of immunosuppressive therapy. Kidney Int 1996 50(4) 1089-100. 

Lewis RM,Van Buren CT, Radovancevic B, Frazier OFi, Janney RP, Powers PL, Golden DL, Giannakis JG, MacrisMP, Kerman RH, et al. impact of long-term cyclosporine immunosuppressive therapy on native kidneys versus renal allografts serial renal function in heart and kidney transplant recipients. J Fleart Lung Transplant 1991 10 63-70. 

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