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

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

OBJECTIVETo investigate the mechanism of action of emodin for suppressing acute allograft rejection in a rat model of liver transplantation.

METHODSBrown Norway (BW) recipient rats of orthotopic liver transplantation (OLT) were divided into three groups, Group A receiving isografting (with BW rats as donor), Group B receiving allografting (with Lewis rats as donor), Group C receiving allografting and emodin treatment (50 mg/kg daily). They were sacrificed on day 7 of post-transplantation, and their hepatic histology, plasma cytokine levels, and T-cell subset expression were detected.

RESULTSCompared with those in Group A, rats: in Group B exhibited severe allograft rejection with a rejection activity index (RAI) of 7.67+/-0.98, extensive hepatocellular apoptosis with an apoptosis index (AI) of 35.83+/-2.32, and elevated plasma levels of interleukin-2 (IL-2), interleukin-10 (IL-10), tumor necrosis factor-alpha (TNF-alpha), CD4(+) and CD4 CD4(+)/CD8(+) ratio. However, recipients in Group C showed a decrease in histological grade of rejection and hepatocellular apoptosis, as well as a decrease in plasma levels of IL-2, TNF-alpha, CD4(+) and CD4(+)/CD8(+) ratio, but elevated levels of IL-10 as compared with the allograft group.

CONCLUSIONPost-OLT acute rejection could be attenuated by emodin, its mechanism of action may be associated with protecting hepatocytes from apoptosis, polarizing the Th 1 paradigm to Th2, and inhibiting the proliferation of CD4(+) T cell in plasma.

Acute Disease ; Animals ; Apoptosis ; drug effects ; Cytokines ; blood ; Drug Evaluation, Preclinical ; Emodin ; pharmacology ; therapeutic use ; Graft Rejection ; prevention & control ; Immunosuppressive Agents ; pharmacology ; therapeutic use ; Liver ; drug effects ; pathology ; ultrastructure ; Liver Transplantation ; immunology ; rehabilitation ; Rats ; Rats, Inbred BN ; Rats, Inbred Lew ; T-Lymphocyte Subsets ; immunology ; pathology ; Transplantation, Homologous

OBJECTIVETo investigate the pathologic monitoring of intestinal graft rejection in auxiliary en-bloc liver-small bowel transplantation in pigs.

METHODSFifty outbred long-white pigs were randomized into three groups, and the auxiliary composite liver-small bowel allotransplantations were undertaken in 10 pigs in group A and group B while segment small bowel allotransplantations were undertaken in 10 pigs in group C. Group A and C were not treated with immunosuppressive drugs while group B was treated with cyclosporine A and methylprednisolone. The postoperative intestinal graft rejections were monitored by biopsy through the jejunostomy or ileuostomy on 1, 3, 5, 7, 14, 21 and 30 days after operation. Through routine management, the specimens were directly examined via optical and electronic microscope respectively.

RESULTSAs shown from pathological data, the median initial time of postoperative rejection in group A was 8 days (ranged from 7 to 12), later than that in group C (5 days:ranged from 3 to 5), P<0.05). On the 7th day postoperatively, the rejection scores in group A was 1.11+/-0.20, lower than that in group C(2.56+/-0.18, P<0.05), but higher than that in group B(0.20+/-0.13, P<0.05). Ultrastructure also showed more severe intestinal graft rejection in intestinal transplantation than that in combined transplantation. The median survival time was 9 days(ranged from 7 to 25) in group A and 12 days(ranged from 7 to 20) in group C, while all the pigs in group B lived longer than 30 days.

CONCLUSIONThe pathological assessment through the jejunostomy or ileuostomy biopsy is a convenient method to monitor the postoperative graft rejections in intestinal related transplantation.

Animals ; Female ; Graft Rejection ; prevention & control ; Graft Survival ; Intestine, Small ; pathology ; transplantation ; ultrastructure ; Liver Transplantation ; adverse effects ; immunology ; Male ; Swine ; Transplantation, Homologous

We performed this study to investigate the feature of rejection in porcine-to-rat corneal orthotopic transplantation and to evaluate the effect of cyclosporine and mycophenolate on the xeno-rejection. Orthotopic corneal transplantation was done at 91 Sprague-Dawley rats, and they were divided into 10 groups based on the combination of immunosuppressants including dexamethasone, cyclosporine, and mycophenolate mofetil. Graft survival was analyzed and grafted eyes were examined with Hematoxylin & Eosin and CD4 or CD8 staining. Enzyme-linked immunosorbent assays were done for interleukin-2 (IL-2), IL-4, IL-5, IL-10, and interferon (IFN)-gamma in cornea, lacrimal gland, and cervical lymph nodes. The longest median survival of the immune suppressant group was 11.00+/-1.96 days, which showed no statistical differences compared with that of control (8.00+/-1.52 days). The neutrophils were prominent in the early phase but soon gave way to the monocytes. The number of CD8+ cells was higher than that of CD4+ cells. IL-2 and IFN-gamma markedly increased at 10 to13 days in cornea, lacrimal glands, and cervical lymph nodes, which showed a decrease with immunosuppressants except in the cornea. In conclusion, cyclosporine and mycophenolate could not prevent the rejection in porcine to rat orthotopic corneal xenograft associated with infiltraton of CD8+ and innate immune cells.
Animals ; *Corneal Transplantation ; Cyclosporine/*pharmacology ; Cytokines/metabolism ; Graft Rejection/immunology/pathology/*prevention & control ; Graft Survival/*drug effects ; Immunosuppressive Agents/*pharmacology ; Interferon-gamma/metabolism ; Interleukin-10/metabolism ; Interleukin-2/metabolism ; Interleukin-4/metabolism ; Interleukin-5/metabolism ; Mycophenolic Acid/*analogs & derivatives/pharmacology ; Neutrophils/immunology ; Rats ; Rats, Sprague-Dawley ; Swine ; Transplantation, Heterologous

OBJECTIVETo investigate the expression of fractalkine (FKN) and its receptor CX3CR1 in cardiac allografts and the effect of Cyclosporin A (CsA).

METHODSThree groups of rats underwent heterotopic cardiac transplantation, 45 cases in each group and 5 cases in control group: SD to SD regarded as isograft group (group A), Wistar to SD divided into CsA untreated allograft group (group B) and CsA treated allograft group (group C), normal SD rats as control group. The FKN mRNA expression was detected by one-step RT-PCR method and the expression of FKN and CX3CR1 protein was detected by standard ABC immunohistochemical technique.

RESULTSThe expression of FKN mRNA and protein was weak in both isografts and normal heart specimens. The changes of FKN mRNA expression were correlated with the process of acute allograft rejection. The peak of FKN mRNA expression (0.8 +/- 0.26) appeared on the seventh day after transplantation, which could be down-regulated by CsA significantly (t = 2.390, P < 0.05). FKN protein was located in endothelia cells and its receptor CX3CR1 was located in infiltrating mononuclear cells in allografts.

CONCLUSIONSUpregulation of FKN and its receptor was significantly correlated with the trafficking of mononuclear cells which play an important role in acute allograft rejection. It may be one of the important mechanisms of CsA to intervene the acute rejection by inhibiting the activation of the FKN-CX3CR1 pathway.

Acute Disease ; Animals ; CX3C Chemokine Receptor 1 ; Chemokine CX3CL1 ; Chemokines, CX3C ; genetics ; metabolism ; Cyclosporine ; pharmacology ; Graft Rejection ; immunology ; pathology ; prevention & control ; Heart Transplantation ; immunology ; pathology ; Immunohistochemistry ; Male ; Membrane Proteins ; genetics ; metabolism ; RNA, Messenger ; metabolism ; Rats ; Rats, Sprague-Dawley ; Rats, Wistar ; Receptors, Cytokine ; genetics ; metabolism ; Receptors, HIV ; genetics ; metabolism ; Reverse Transcriptase Polymerase Chain Reaction ; Transplantation, Homologous