Gene Therapy-Mediated CD40L and CD28 Co-stimulatory Signaling Blockade plus Transient Anti-xenograft Antibody Suppression Induces Long-Term Acceptance of Cardiac Xenografts

2区 · 医学

Article

作者: Hashimoto, Taku ; Furukawa, Hiroyouki ; Masunaga, Taro ; Yamashita, Kenichiro ; Hua, Nan ; Todo, Satoru ; Uede, Toshimitsu ; Fujita, Miri

BACKGROUNDThe authors have previously demonstrated that inhibition of CD28 and CD40 ligand (CD40L) co-stimulatory signals by adenovirus-mediated cytotoxic T-lymphocyte-associated (CTL) antigen 4 (A4) immunoglobulin (Ig) and CD40Ig gene therapies induces tolerance or long-term acceptance in rat liver and heart allograft transplantation. In this study, the authors examined whether co-stimulation blockade with a brief course treatment of FK779, a novel leflunomide derivative, would be an ideal strategy for controlling xenograft rejection.METHODSHamster hearts were transplanted into Lewis rats. Adenovirus vector coding (Ad) CD40Ig, CTLA4Ig, or LacZ gene (1 x 10(9) plaque-forming units) was administered intravenously to recipient rats 2 days before or immediately after xenografting. FK779 (10 mg/kg/day) was administered orally to recipients for 7 days beginning on day -1. Graft survival, graft histology, and xenoreactive antibodies were examined.RESULTS: Both untreated and AdLacZ-treated control rats rejected cardiac xenografts, with a median survival time (MST) of 3 days. Co-stimulatory blockade alone by AdCTLA4Ig, AdCD40Ig, or both could not overcome such delayed xenograft rejection (DXR) (MST, 3-4 days). Under a short-course FK779 treatment that suppressed T-cell-independent xenoreactive antibodies, administration of AdCD40Ig (MST, 30.5 days) but not AdCTLA4Ig (MST, 9 days) significantly prolonged xenograft survival as compared with the FK779 monotherapy (MST, 7 days). In contrast, DXR and cellular rejection were controlled successfully and all xenografts were accepted for over 100 days when AdCTLA4Ig and AdCD40Ig were administered under FK779 induction therapy. However, chronic rejection was present in all long-term surviving xenografts.CONCLUSIONS: Gene therapy-based co-stimulation blockade with FK779 induction treatment seems to be an attractive strategy with which to control xenograft rejection.

2003-06-15·Transplantation2区 · 医学

Synergistic effects of malononitrilamides (FK778, FK779) with tacrolimus (FK506) in prevention of acute heart and kidney allograft rejection and reversal of ongoing heart allograft rejection in the rat1

2区 · 医学

Article

作者: Zhu, Shengyun ; Bekersky, Ihor ; Hebert, Marie J. ; Fitzsimmons, William E. ; Ouyang, Jun ; Qi, Shijie ; Xu, Dasheng ; Bilolo, Kupa K. ; Chen, Huifang ; Wang, Xiang ; Jiang, Wenlei

BACKGROUNDThe effects of tacrolimus (FK506) and malononitrilamides (MNA) (FK778 and FK779) monotherapy and combination therapy were examined in prevention of acute heart and kidney allograft rejection and reversal of ongoing acute heart allograft rejection in the rat.METHODSBrown Norway (RT1n)-to-Lewis (RT11) and ACI (RT1a)-to-Lewis (RT11) combinations were used, respectively, for heart and kidney transplantation models. Immunosuppressants were administered orally from day 1 to day 14 for preventing acute rejection and from day 4 to day 34 after transplantation for the reversal of ongoing acute rejection.RESULTSIn the prevention of acute heart rejection model, recipient rats treated with monotherapy of tacrolimus or MNA (FK778, FK779) showed a dose-related prolongation of mean survival time (MST) compared with naive control rats (P<0.01). The mean survival time in combination therapy of tacrolimus (FK506) and FK778 indicated that an additive to synergistic interaction was produced when compared with the respective monotherapies (combination index [CI]=0.631-1.022). These results were reproducible with tacrolimus and FK779 combination therapy (CI=0.572-0.846). Furthermore, similar results were also found in the prevention of acute kidney allograft rejection in the rat (CI=0.137-0.516). In the reversal of ongoing acute heart allograft rejection, combination therapy of tacrolimus and FK778 demonstrated a strong synergistic interaction (CI=0.166-0.970) compared with monotherapy of tacrolimus or FK778.CONCLUSIONSCombination therapy of tacrolimus and MNA (FK778, FK779) produces synergistic effects in prevention of acute heart and kidney rejection and reversal of ongoing heart allograft rejection in the rat.

2002-12-01·Current Drug Target -Cardiovascular & Hematological Disorders

New Immunosuppressants in Clinical Trial

Review

作者: McAlister, Vivian C

Chemical immunosuppression developed at the beginning of clinical transplantation remains the basis of immunosuppressive protocols used today. Clinical trials of new agents focus on the incremental improvement in one of four areas of immunotherapy: induction, basic maintenance, adjuvant and steroid therapy. Induction immunotherapy developments include the use of humanized antibodies, specific targets (basiliximab, daclizumab) and lymphocyte depletion (anti-thymocyte globulin, campath-1H). Promising results from pilot trials allow for subsequent low dose maintenance monotherapy. New inhibitors of calcineurin isoforms (ISATx247) may disassociate the anti-rejection effect from the toxicity of conventional calcineurin inhibitors. Revived investigation of older anti-proliferative or anti-metabolite drugs (rapamycin, mycophenolic acid, leflunomide) show promise in preventing B-cell responses and reducing chronic rejection but development of derivatives (everolimus, mycophenolate mofetil, ERL 080, MNA 279, MNA 715) may have a stronger commercial than experimental basis. Trials of steroid immunotherapy have focused on steroid elimination but trial of newer locally active steroids may be beneficial.

100 项与 FK-779 相关的药物交易

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