Changes in ABCB1 mRNA Expression in Peripheral Blood Cells before and after Renal Transplantation.

Cyclosporine (CSA), which is one of the substrates of ATP binding cassette subfamily B member 1 (ABCB1), is widely used as an immunosuppressant in patients undergoing transplantation. The expression level of P-glycoprotein on lymphocytes that is encoded by ABCB1 gene is considered to be one of the major causes of differences in intracellular CSA concentration. The clinical relevance of ABCB1 mRNA expression in peripheral blood was analyzed.

Clinical relevance of post-transplant pharmacodynamic analysis of cyclosporine in renal transplantation.

Although therapeutic drug monitoring based on blood concentration has been widely implemented in transplant recipients treated with immunosuppressive agents, clinical adverse events such as rejection, infection or drug-induced toxicity caused by inappropriate dosage cannot be completely controlled. Development of an effective assay for optimized immunosuppression would be desirable, which can potentially lead to personalized medicine in renal transplantation. Cyclosporine (CSA) pharmacodynamic analysis using carboxyfluorescein diacetate succinimidyl ester (CFSE)-based T cell proliferation assay was examined in 66 kidney transplant recipients before and after transplantation.

Comparative analysis of drug action on B-cell proliferation and differentiation for mycophenolic acid, everolimus, and prednisolone.

Background: Although more attention has been paid recently to B-cell immunity, assay for B-cell analysis has yet to be clinically applicable because, unlike T cell, a B-cell culture system has not been well established.

Methods: We attempted to develop an in vitro culture system for the proliferation and differentiation of peripheral B cells into plasma cells, and to analyze the action of everolimus (EVR), mycophenolic acid (MPA), and prednisolone (PRD).

Results: Using a three-step culture system, peripheral CD19 B cells could differentiate into plasma cells and produce IgG antibody.

AMP-activated protein kinase as a promoting factor, but complement and thrombin as limiting factors for acquisition of cytoprotection: implications for induction of accommodation.

Accommodation has been termed as a condition without graft rejection even in the presence of antidonor antibody. We previously reported an in vitro accommodation model, which demonstrated that preincubation of A/B antigen-expressing endothelial cells with anti-A/B antibody resulted in ERK inactivation followed by resistance to complement-mediated cytotoxicity through the induction of complement regulatory genes. However, under the in vivo condition, the effects of complement and coagulation system cannot be ignored.

Production of cloned pigs expressing human thrombomodulin in endothelial cells.

For long-term xenograft survival, coagulation control is one of the remaining critical issues. Our attention has been directed toward human thrombomodulin (hTM), because it is expected to exhibit the following beneficial effects on coagulation control and cytoprotection: (i) to solve the problem of molecular incompatibility in protein C activation; (ii) to exert a role as a physiological regulator, only when thrombin is formed; (iii) to suppress direct prothrombinase activity; and (iv) to have anti-inflammatory properties. hTM gene was transfected into pig (Landrace/Yorkshire) fibroblasts using pCAGGS expression vector and pPGK-puro vector.

Comparative study on signal transduction in endothelial cells after anti-a/b and human leukocyte antigen antibody reaction: implication of accommodation.

Background: Recent development of immunosuppressive therapy has provided a platform for clinical human leukocyte antigen (HLA)- and ABO-incompatible kidney transplantation. However, the prognosis seems to be different between the two. Accommodation, the condition of no injury even in the presence of antidonor antibody, is one of the key factors for successful transplantation with antidonor antibody.

Clinical significance of regulatory T-cell-related gene expression in peripheral blood after renal transplantation.

Background: Regulatory T cells (Tregs) have been suggested to be deeply associated with immune tolerance and long-term graft survival in transplantation. Some recipients with stable graft function (ST) could possibly minimize immunosuppression during the maintenance period. However, effective assays for assessing the suitability of patients have yet to be established.

Successful cross-breeding of cloned pigs expressing endo-beta-galactosidase C and human decay accelerating factor.

Background: For successful organ xenotransplantation, genetically engineered pigs have been actively produced. Our attention has focused on (i) reduction of alphaGal expression by its digestion enzyme, endo-beta-galactosidase C (EndoGalC), and (ii) inhibition of complement activation by human decay accelerating factor (hDAF). Cell sorting and nuclear transfer enabled the effective production of cloned pigs expressing transgene at high levels.

Evaluation of interleukin-2 mRNA in whole blood as a parameter for monitoring cyclosporine pharmacodynamics.

Inhibition of cytokine production is the main immunosuppressive effect of cyclosporine (CsA), which is widely used in organ transplantation. Pharmacodynamic (PD) assay for evaluating the inhibition of interleukin-2 (IL-2) production for each patient could provide a more appropriate dosing regimen. We measured the suppression of IL-2 mRNA expression in whole blood following the addition of a range of CsA concentrations by a real-time reverse transcription-polymerase chain reaction (RT-PCR) method.

Removal of blood group A/B antigen in organs by ex vivo and in vivo administration of endo-beta-galactosidase (ABase) for ABO-incompatible transplantation.

Background: ABO incompatibility in organ transplantation is still a high risk factor for antibody-mediated rejection, despite the progress in effective treatments. We have explored the possibility of using the enzyme to remove the blood type A/B antigen in organs.

Methods: Recombinant endo-beta-galactosidase (ABase), which releases A/B antigen, was produced in E.

Carvedilol increases ciclosporin bioavailability by inhibiting P-glycoprotein-mediated transport.

Carvedilol is often used to treat hypertension and for prophylaxis in vascular sclerosis in renal transplant recipients, who require concomitant treatment with ciclosporin. However, there are few reports regarding the pharmacokinetic interactions between carvedilol and ciclosporin. We have investigated the potential effects of carvedilol on the pharmacokinetics of ciclosporin, and examined the inhibitory effects of carvedilol on P-glycoprotein-mediated transcellular transport using Caco2 cells.

Prophylactic treatment of antibody-mediated rejection with high-dose mizoribine and pharmacokinetic study.

Although mizoribine (MZ), which inhibits inosine monophosphate dehydrogenase in the same way as mycophenolate mofetil, recently proved more effective when higher doses were administered than previously approved, neither the optimal dosage nor blood concentration has yet been clarified. We aimed at investigating the effect of high-doses of MZ on prevention of anti-donor antibody (Ab) production and acute Ab-mediated rejection (AMR) on the basis of the pharmacokinetic profile in a pig kidney transplantation model. Group 1 (n = 5) received cyclosporin microemulsion (6 mg/kg) and prednisolone (0.

Sequence effect of docetaxel and carboplatin on toxicity, tumor response and pharmacokinetics in non-small-cell lung cancer patients: a phase I study of two sequences.

Purpose: To investigate sequence effects on toxicity, tumor response and pharmacokinetics of docetaxel and carboplatin, together with a determination of the maximum-tolerated dose (MTD) and recommended dose for each schedule.

Patients And Methods: A total of 46 chemotherapy-naive patients with advanced non-small-cell lung cancer were randomized to receive docetaxel before (schedule A) or after (schedule B) carboplatin. The dose levels studied were [docetaxel (mg/m(2))/carboplatin (mg x min/ml)] 50/5, 60/5, 60/6, 60/7, and 70/6.

Potential value of high-dose mizoribine as rescue therapy for ongoing acute humoral rejection.

Mizoribine (MZ) inhibits the proliferation of lymphocytes selectively via inhibition of inosine monophosphate dehydrogenase, like mycophenolate mofetil (MMF). The clinical dosage of MZ (2-5 mg/kg) is much lower than that of MMF (20-60 mg/kg). The purpose of this study was to examine whether high-dose MZ would be effective for treatment of acute humoral rejection.

Amlodipine, but not MDR1 polymorphisms, alters the pharmacokinetics of cyclosporine A in Japanese kidney transplant recipients.

Background: Cyclosporine A (CsA) is a critical immunosuppressive drug with a narrow therapeutic range and wide interindividual variation in its pharmacokinetics. Many factors, including P-glycoprotein (PGP), influence the oral bioavailability and interpatient variability of CsA. A number of polymorphisms have been identified in the human MDR1 gene, and some of them have been found to be associated with an altered expression of PGP.

Valproic acid increases biliary copper excretion in the rat.

The effect of valproic acid (VPA) on the copper absorption and disposition in rat small intestine was investigated using an in situ recirculating perfusion method. Following addition of VPA (20 mg) to the perfusion of 30 ml of 0.9% sodium chloride solution (2 microg/ml copper as CuSO(4)) there were no significant differences in copper decline during the perfusion.

Interference of hematocrit in the tacrolimus II microparticle enzyme immunoassay.

The authors studied the effect of hematocrit, bilirubin, and alkaline phosphatase on microparticle enzyme immunoassay for tacrolimus II (MEIA II) using specimens of whole blood obtained from 33 patients undergoing cyclosporine treatment. Tacrolimus was added to these samples at a final concentration of 7.5 microg/L and 15 microg/L.