BACKGROUND: The primary limitation to kidney transplantation is organ shortage. Recent progress in gene editing and immunosuppressive regimens has made xenotransplantation with porcine organs a possibility. However, evidence in pig-to-human xenotransplantation remains scarce, and antibody-mediated rejection (AMR) is a major obstacle to clinical applications of xenotransplantation. METHODS: We conducted a kidney xenotransplantation in a brain-dead human recipient using a porcine kidney with five gene edits (5GE) on March 25, 2024 at Xijing Hospital, China. Clinical-grade immunosuppressive regimens were employed, and the observation period lasted 22 days. We collected and analyzed the xenograft function, ultrasound findings, sequential protocol biopsies, and immune surveillance of the recipient during the observation. RESULTS: The combination of 5GE in the porcine kidney and clinical-grade immunosuppressive regimens prevented hyperacute rejection. The xenograft kidney underwent delayed graft function in the first week, but urine output increased later and the single xenograft kidney maintained electrolyte and pH homeostasis from postoperative day (POD) 12 to 19. We observed AMR at 24 h post-transplantation, due to the presence of pre-existing anti-porcine antibodies and cytotoxicity before transplantation; this AMR persisted throughout the observation period. Plasma exchange and intravenous immunoglobulin treatment mitigated the AMR. We observed activation of latent porcine cytomegalovirus toward the end of the study, which might have contributed to coagulation disorder in the recipient. CONCLUSIONS 5GE and clinical-grade immunosuppressive regimens were sufficient to prevent hyperacute rejection during pig-to-human kidney xenotransplantation. Pre-existing anti-porcine antibodies predisposed the xenograft to AMR. Plasma exchange and intravenous immunoglobulin were safe and effective in the treatment of AMR after kidney xenotransplantation.
Transplantation, Heterologous/methods* ; Kidney Transplantation/methods* ; Heterografts/pathology* ; Immunoglobulins, Intravenous/administration & dosage* ; Graft Survival/immunology* ; Humans ; Animals ; Sus scrofa ; Graft Rejection/prevention & control* ; Kidney/pathology* ; Gene Editing ; Species Specificity ; Immunosuppression Therapy/methods* ; Plasma Exchange ; Brain Death ; Biopsy ; Male ; Aged

OBJECTIVE: To prepare decellularized nerve grafts from alpha-1, 3-galactosyltransferase (GGTA1) gene-edited pigs and explore their biocompatibility for xenotransplantation. METHODS: The sciatic nerves from wild-type pigs and GGTA1 gene-edited pigs were obtained and underwent decellularization. The alpha-galactosidase (α-gal) content in the sciatic nerves of GGTA1 gene-edited pigs was detected by using IB4 fluorescence staining and ELISA method to verify the knockout status of the GGTA1 gene, and using human sciatic nerve as a control. HE staining and scanning electron microscopy observation were used to observe the structure of the nerve samples. Immunofluorescence staining and DNA content determination were used to evaluate the degree of decellularization of the nerve samples. Fourteen nude mice were taken, and subcutaneous capsules were prepared on both sides of the spine. Decellularized nerve samples of wild-type pigs ( n=7) and GGTA1 gene-edited pigs ( n=7) were randomly implanted in the subcutaneous capsules. Blood was drawn at 1, 3, 5, and 7 days after implantation to detect neutrophil counting. RESULTS: IB4 fluorescence staining and ELISA detection showed that GGTA1 gene was successfully knocked out in the nerves of GGTA1 gene-edited pigs. HE staining showed that the structure of the decellularized nerve from GGTA1 gene-edited pigs was well preserved; the nerve basement membrane tube structure was visible under scanning electron microscopy; no cell nuclei was observed, and the extracellular matrix components was retained in the nerve grafts by immunofluorescence staining; and the DNA content was significantly reduced when compared with the normal nerves ( P<0.05). In vivo experiments showed that the number of neutrophils in the two groups were similar at 1, 3, and 7 days after implantation, with no significant difference ( P>0.05); only at 5 days, the number of neutrophils was significantly lower in the GGTA1 gene-edited pigs than in the wild-type pigs ( P<0.05). CONCLUSION The decellularized nerve grafts from GGTA1 gene-edited pigs have well-preserved nerve structure, complete decellularization, retain the natural nerve basement membrane tube structure and components, and low immune response after xenotransplantation through in vitro experiments.
Animals ; Transplantation, Heterologous ; Galactosyltransferases/genetics* ; Sciatic Nerve/immunology* ; Swine ; Tissue Engineering/methods* ; Humans ; Graft Rejection/prevention & control* ; Gene Editing ; Mice ; Mice, Nude ; Heterografts/immunology* ; Animals, Genetically Modified ; Tissue Scaffolds ; Decellularized Extracellular Matrix

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 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