BackgroundImmunosuppressive agents are still inefficient in preventing biopsy-proven acute rejection (BPAR) after expanded criteria donor (ECD) kidney transplantation. The aim of this study was to investigate the relationships between early immunosuppressive exposure and the development of BPAR.

MethodsWe performed a retrospective study of 58 recipients of ECD kidney transplantation treated with enteric-coated-mycophenolate sodium, tacrolimus (Tac), and prednisone. The levels of mycophenolic acid-area under the curve (MPA-AUC) and Tac Cwere measured at the 1 week and the 1 month posttransplant, respectively. The correlation was assessed by multivariate logistic regression.

ResultsThe occurrence rates of BPAR and antibody-mediated rejection were 24.1% and 10.3%, respectively. A low level of MPA-AUC at the 1 week posttransplant was found in BPAR recipients (38.42 ± 8.37 vs. 50.64 ± 13.22, P < 0.01). In addition, the incidence of BPAR was significantly high (P < 0.05) when the MPA-AUClevel was <30 mg·h·L at the 1 week (15.0% vs. 44.4%) or the Tac Cwas <4 ng/ml at the 1 month posttransplant (33.3% vs. 21.6%). Multivariable logistic regression analysis showed that the MPA-AUC at the 1 week (OR: 0.842, 95% CI: 0.784-0.903) and the Tac Cat the 1 month (OR: 0.904, 95% CI: 0.822-0.986) had significant inverse correlation with BPAR (P < 0.05).

ConclusionsLow-level exposure of MPA and Tac Cin the early weeks posttransplant reflects an increased acute rejection risk, which suggested that MPA-AUC <30 mg·h·L and Tac C <4 ng/ml should be avoided in the first few weeks after transplantation.

Adult ; Female ; Graft Rejection ; immunology ; prevention & control ; Humans ; Immunosuppressive Agents ; chemistry ; therapeutic use ; Kidney Transplantation ; adverse effects ; methods ; Male ; Middle Aged ; Mycophenolic Acid ; chemistry ; therapeutic use ; Retrospective Studies ; Tacrolimus ; chemistry ; therapeutic use ; Time Factors

No abstract available.
Adult ; Female ; Graft Rejection/immunology/*prevention & control ; Graft Survival ; *Hematopoietic Stem Cell Transplantation ; Humans ; *Immune Tolerance ; Immunosuppressive Agents/therapeutic use ; Kidney Failure, Chronic/diagnosis/*surgery ; *Kidney Transplantation ; Living Donors ; Siblings ; Time Factors ; *Transplantation Chimera ; Treatment Outcome

OBJECTIVETo review the current status and progress on pig islet xenotransplantation.

DATA SOURCESData used in this review were mainly from English literature of Pubmed database. The search terms were "pig islet" and "xenotransplantation".

STUDY SELECTIONThe original articles and critical reviews selected were relevant to this review's theme.

RESULTSPigs are suggested to be an ideal candidate for obtaining available islet cells for transplantation. However, the potential clinical application of pig islet is still facing challenges including inadequate yield of high-quality functional islets and xenorejection of the transplants. The former can be overcome mainly by selection of a suitable pathogen-free source herd and the development of isolation and purification technology. While the feasibility of successful preclinical pig islet xenotranplantation provides insights in the possible mechanisms of xenogeneic immune recognition and rejection to overwhelm the latter. In addition, the achievement of long-term insulin independence in diabetic models by means of distinct islet products and novel immunotherapeutic strategies is promising.

CONCLUSIONSPig islet xenotransplantation is one of the prospective treatments to bridge the gap between the needs of transplantation in patients with diabetes and available islet cells. Nonetheless, further studies and efforts are needed to translate obtained findings into tangible applications.

Animals ; Graft Rejection ; immunology ; prevention & control ; Islets of Langerhans Transplantation ; immunology ; methods ; Swine ; Transplantation, Heterologous ; methods

BACKGROUNDOX40/OX40 ligand (OX40/OX40L) and programmed death-1/programmed death ligand-1 (PD-1/PD-L1) costimulatory signals play important roles in T cell-induced immune responses. The aim of this study was to investigate the roles of OX40/OX40L and PD-1/PD-L1 costimulatory pathways in mouse islet allograft rejection.

METHODSLentiviral vectors containing OX40L siRNA sequences and an adenovirus vector containing the PD-L1 gene were constructed. The streptozotocin-induced model of diabetes was established in C57BL/6 (H-2(b)) mice. Diabetic C57BL/6 mice were randomly allocated into five groups: group 1, untreated control; group 2, Ad-EGFP treatment; group 3, Ad-PD-L1 treatment; group 4, OX40L-RNAi-LV treatment; group 5, OX40L-RNAi-LV combined with Ad-PD-L1 treatment. Lentiviral vector and the adenovirus vector were injected, singly or combined, into the caudal vein one day before islet transplantation. The islets of DBA/2 (H-2(d)) mice were transplanted into the renal subcapsular space of the diabetic recipients. Recipient blood glucose and the survival time of the allografts were monitored. Antigen-specific mixed lymphocyte reaction was also evaluated.

RESULTSThe recombinant lentiviral RNA interference vector OX40L-RNAi-LV reduced OX40L protein expression by 70%. The recombinant adenovirus vector Ad-PD-L1 increased PD-L1 protein expression in vivo in C57BL/6 recipient mice. Combined OX40L-RNAi-LV/Ad-PD-L1 treatment induced a synergistic protective effect in pancreatic islet allografts. Allograft survival time in the combined treatment group was (92.27±9.65) days, not only longer than that of the control ((6.51±0.27) days) and Ad-EGFP groups ((7.09±0.13) days) (P < 0.01), but also significantly longer than that of Ad-PD-L1 and OX40L-RNAi-LV single treatment groups ((40.64±3.95) days and (55.14±5.48) days respectively, P < 0.01). The blood glucose concentration of recipient mice in the combined treatment group was also stable and kept within the normal range. Flow cytometry analysis showed that combined OX40L-RNAi-LV/Ad-PD-L1 treatment significantly decreased proliferation in an antigen-specific mixed lymphocyte reaction. After donor DBA/2 lymphocyte stimulation, 89.71% of lymphocytes from recipient combination treatment C57BL/6 mice were not split and proliferated. In contrast, after stimulation with third party Lewis rat lymphocytes, only 45.84% lymphocytes of C57BL/6 mice were not split and proliferated.

CONCLUSIONSThis study demonstrates the successful construction of the recombinant lentivirus vector OX40L-RNAi-LV and adenovirus vector Ad-PD-L1 for the blockade of OX40/OX40L and activation of PD-1/PD-L1 costimulatory pathways simultaneously in pancreatic islet allografts in diabetic mice. Combination therapy with these two vectors resulted in inhibition of T cell activation, synergistically prolonging the survival time of pancreatic islet allografts.

Animals ; B7-H1 Antigen ; genetics ; metabolism ; Graft Rejection ; genetics ; prevention & control ; Islets of Langerhans Transplantation ; immunology ; Male ; Mice ; Mice, Inbred C57BL ; OX40 Ligand ; genetics ; metabolism ; Receptors, OX40 ; genetics ; metabolism ; Transplantation, Homologous

This study aimed to investigate the effect of bortezomib in the desensitization and treatment of acute antibody mediated rejection (AAMR) in kidney transplantation. Nine patients who received bortezomib therapy for desensitization (DSZ group, n = 3) or treatment of AAMR (AAMR group, n = 6) were included in this study. In the DSZ group, 2 patients required DSZ owing to positive cross match and 1 owing to ABO mismatch with high baseline anti-ABO antibody titer (1:1,024). Bortezomib was used at 1, 3, 8, and 11 days from the start of the treatment. In the AAMR group, 3 patients showed full recovery of allograft function after bortezomib use and decrease in donor specific anti-HLA antibody (HLA-DSA). However, 3 patients did not respond to bortezomib and experienced allograft failure. In the DSZ group, negative conversion of T-CDC (complement-dependent cytotoxicity) was achieved, and HLA-DSA was decreased to lower than a weak level (median fluorescence intensity [MFI] < 5,000) in 2 patients. In the case of ABO mismatch kidney transplantation, the anti-A/B antibody titer decreased to below the target (< or = 1:16) after bortezomib therapy. Therefore, bortezomib could be an alternative therapeutic option for desensitization and treatment of AAMR that is unresponsive to conventional therapies.
Adult ; Boronic Acids/*therapeutic use ; Desensitization, Immunologic/*methods ; Female ; Graft Rejection/*drug therapy/*prevention & control ; HLA Antigens/immunology ; Humans ; Kidney/surgery ; Kidney Transplantation/*methods ; Male ; Middle Aged ; Pyrazines/*therapeutic use ; Treatment Outcome

Recent data suggest that activation of aryl hydrocarbon receptor (AhR) by its high-affinity ligand 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) results in expansion of regulatory T (Treg) cells and suppresses the development of autoimmune and allergic diseases in several models. Treg cells have been increasingly documented to suppress allograft rejection and even to establish stable long-term graft acceptance. However, the involvement of TCDD in the regulation of solid organ transplantation rejection is largely unknown. Here, we examined whether activation of AhR with TCDD altered cardiac allograft rejection in an allogeneic heart transplant model. Recipient C57BL/6 (H-2b) mice were administrated with a single intraperitoneal injection of TCDD, and the murine cardiac transplant models from BALB/c (H-2d) to C57BL/6 (H-2b) were built 24 h later. The complete cessation of cardiac contractility was defined as the observation endpoint. The effect of TCDD on T-cell proliferation was assessed by mixed lymphocyte reaction (MLR). Histological and immunohistochemical analyses were performed to estimate the severity of rejection. The phenotype and cytokine profile of lymphocytes were analyzed by flow cytometry and enzyme-linked immunosorbent assay (ELISA). Activation of AhR remarkably prolonged the survival of cardiac allografts to more than 20 days. In vitro, TCDD ugregulated the frequency of CD4+CD25+Foxp3+ Treg cells and suppressed the proliferation of T lymphocytes. In vivo, the prolonged survival time was associated with increased number of Treg cells in allografts and spleens. Furthermore, the secretion of interferon-γ (IFN-γ) and interleukin-17 (IL-17) was reduced to less than 50% of that of the PBS treatment control group by TCDD treatment, whereas IL-10 was elevated to 10-fold of that of the PBS treatment control group. Collectively, our data indicate that activation of AhR with a single dose of TCDD significantly prolonged the survival of fully allogeneic cardiac grafts, and the mechanism underlying this effect might be involved in the induction of Treg cells.
Animals ; Graft Rejection ; immunology ; pathology ; prevention & control ; Graft Survival ; drug effects ; immunology ; Heart Transplantation ; adverse effects ; methods ; Male ; Mice ; Mice, Inbred BALB C ; Mice, Inbred C57BL ; Polychlorinated Dibenzodioxins ; pharmacology ; Receptors, Aryl Hydrocarbon ; immunology ; T-Lymphocytes ; immunology ; pathology ; T-Lymphocytes, Regulatory ; immunology ; pathology

No abstract available.
Animals ; Antigen-Presenting Cells/immunology ; Graft Rejection/immunology/*prevention & control ; Graft Survival ; *Histocompatibility ; Humans ; Immunosuppression/*methods ; Intercellular Adhesion Molecule-1/immunology ; Isoantigens/*immunology ; Organ Transplantation/*adverse effects ; *Transplantation Tolerance

OBJECTIVETo explore the effect of CD40 blockade in suppressing acute rejection of renal graft in rats.

METHODSWith Wistar rats as the donor and male SD rats as the recipients, rat models of acute renal graft rejection was established. The rat models were divided into therapy group and control group, and in the former group, CD40 ligand (CD40L) monoclonal antibody was injected daily for 4 consecutive days starting on the next day following kidney transplantation. On day 5 after the transplantation, the renal graft was harvested for histological examination, and graft rejection was evaluated semiquantitatively.

RESULTSThe mean semiquantitative score of the renal graft was 0.63∓0.52 in the therapy group, significantly lower than that of the control group (3.72∓1.48, P<0.05).

CONCLUSIONCD40L monoclonal antibody can inhibit acute renal graft in rats.

Animals ; Antibodies, Monoclonal ; pharmacology ; therapeutic use ; CD40 Antigens ; antagonists & inhibitors ; immunology ; CD40 Ligand ; immunology ; Female ; Graft Rejection ; drug therapy ; prevention & control ; Graft Survival ; drug effects ; Kidney Transplantation ; adverse effects ; Male ; Rats ; Rats, Sprague-Dawley ; Rats, Wistar

OBJECTIVETo review this efficacy and safety of bortezomib, a proteasome inhibitor, in the setting of the sensitized transplant candidate.

DATA SOURCESThe data used in this review were from articles published (PubMed) between 2000 to 2010. Additionally abstracts from medical meetings related to transplant were also used.

STUDY SELECTIONArticles were selected if they were trial results or case studies for the use of bortezomib in the sensitized patient population.

RESULTSThe early data using bortezomib as a part of desensitization regimens has shown success. Although one cycle (4 doses) of bortezomib seems to have affect on many patients, it also seems likely that to provide complete desensitization multiple cycles will be required. Regarding safety, bortezomib has been shown to have minimal side effects. The most common side effects reported are those of thrombocytopenia and anemia. These side effects are dose related and self limiting upon discontinuation of the treatment.

CONCLUSIONSBortezomib with plasmapheresis is a promising new alternative to desensitization protocols that use either high dose intravenous immune globulin (IVIG) or low dose IVIG and plasmapheresis. The efficacy on antibody reduction looks to be batter that that of the IVIG based regimens without significant addition toxicity. The results of ongoing prospective trials are positive and their complete results are greatly anticipated.

Boronic Acids ; therapeutic use ; Bortezomib ; Graft Rejection ; immunology ; prevention & control ; Humans ; Protease Inhibitors ; therapeutic use ; Proteasome Endopeptidase Complex ; metabolism ; Pyrazines ; therapeutic use ; Transplants ; adverse effects

Antibodies ; immunology ; Graft Rejection ; drug therapy ; immunology ; prevention & control ; Graft Survival ; immunology ; Humans