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

Establishment of rat models of liver transplantation provides an ideal animal model for resolving the problems of postoperative complications and perioperative treatment of liver transplantation. With in-depth study of the establishment of rat models of liver transplantation, classic "two-cuff" technique has been gradually employed. However, poor surgical field, vascular torsion, biliary tract injury and long anhepatic phase remain unresolved in the process of liver transplantation using traditional techniques. At present, the rat models of liver transplantation at home and abroad are modified mainly from the reconstruction of four vital anatomic structures including the suprahepatic inferior vena cava, portal vein, infrahepatic inferior vena cava and bile duct. Therefore, the latest progress in the reconstruction of the suprahepatic inferior vena cava, portal vein, infrahepatic inferior vena cava and bile duct was reviewed, aiming to provide reference for the establishment of rat models of liver transplantation and promote further development of liver transplantation techniques.

Subclinical research of xenotransplantation involves xenotransplantation trial using brain death donors,which is an important intermediate step from basic research and animal experiments to the clinical application of xenotransplantation.It provides necessary data support for the safety and efficacy of xenotransplantation.In order to promote the safe,orderly,scientific and standardized development of subclinical research on xenotransplantation,the Xenotransplantation Group of Branch of Organ Transplantation of Chinese Medical Association formulated the"Expert Consensus on Subclinical Research of Xenotransplantation(2024 Edition)"based on relevant laws and regulations.The consensus includes aspects such as the selection of donor pigs,recipient selection criteria,legal and ethical requirements,determination of trial termination time,family informed consent system,and brain death determination standards.

Objective:To investigate the influencing of high sodium donor liver transplan-tation from the death of a citizen′s organ donation (DCD) on the prognosis of recipients.Methods:The retrospective cohort study was constructed. The clinicopathological data of 125 pairs of donors and recipients who underwent DCD liver transplantation in Xijing Hospital of Air Force Military Medical University from January 2015 to June 2021 were collected. Of the 125 donors, there were 93 males and 32 females. Of the 125 recipients, there were 92 males and 33 females, aged 48(41,55)years. According to the last time of serum sodium level of donor liver in the 125 recipients, 9 donor livers with serum sodium level ≥170 mmol/L were divided into group 1 (extremely high sodium), 33 donor livers with serum sodium level ≥150 mmol/L and <170 mmol/L were divided into group 2 (moderate high sodium), and 83 donor livers with serum sodium level <150 mmol/L were divided into group 3 (normal sodium), respectively. Observation indicators: (1) postoperative recover situations; (2) follow-up and survival analysis. Measurement data with normal distribution were represented as Mean± SD. Repeated measures were analyzed by repeated measures ANOVA. Measurement data with skewed distribution were represented as M( Q1, Q3), and comparison between groups was analyzed using the Kruskal-Wallis test. Count data were described as absolute numbers, and Pearson chi-square test or Fisher exact probability were used for data test. The Kaplan-Meier method was used to draw survival curves and Log-rank test was used for survival analysis. Results:(1) Postoperative recover situations. The changes of alanine transaminase (AlT), aspartate aminotransferases (AST), total bilirubin (TBil), alkaline phosphatase (ALP), prothrombin time (PT), international normalized ratio (INR), albumin (Alb) and creatinine (Cr) from the first day to the 14th day after operation were (736±972)IU/L to (75±46)IU/L, (1 290±1 651)IU/L to (38±20)IU/L, (102±98)μmol/L to (33±11)μmol/L, (66±34)IU/L to (104±54)IU/L, (19.9±3.3)seconds to (11.3±1.0)seconds, 1.76±0.31 to 1.00±0.08, (34±5)g/L to (38±3)g/L and (91±41)μmol/L to (76±19)μmol/L, respectively, in the recipients of group 1. The above indicators were (505±377)IU/L to (48±46)IU/L, (855±727)IU/L to (24±17)IU/L, (64±42)μmol/L to (32±22)μmol/L, (68±51)IU/L to (91±46)IU/L, (16.8±3.5)seconds to (11.9±1.2)seconds, 1.47±0.30 to 1.04±0.09, (33±4 g/L) to (40±5)g/L and (106±32)μmol/L to (97±27)μmol/L in the recipients of group 2 and (637±525)IU/L to (65±60)IU/L, (929±1 193)IU/L to (33±27)IU/L, (66±48)μmol/L to (33±36)μmol/L, (64±28)IU/L to (125±64)IU/L, (17.2±4.7)seconds to (13.3±12.8)seconds, 1.51±0.42 to 1.05±0.13, (35±6)g/L to (39±4)g/L, (105±44)μmol/L to (94±40)μmol/L in the recipients of groups. Results of overall effect showed there were significant differ-ences in the change trend of TBil (time effect, inter-group effect, interaction effect) in recipients among the three groups after liver transplantation ( Fgroup=5.42, Ftime=22.78, Finteraction=3.85, P<0.05). There were significant differences in the time effect of ALT, AST, ALP, PT, INR, Alb, Cr in recipients among the three groups after liver transplantation ( Ftime=50.17, 36.24, 19.24, 10.55, 59.61, 41.94, 10.82, P<0.05). (2) Follow-up and survival analysis. All recipients were followed up. Cases with early postoperative liver dysfunction, cases with donor liver failure 1 year after operation, cases with biliary complica-tions 1 year after operation, cases with vascular complications 1 year after operation, cases with rejection 1 year after operation were 2, 1, 0, 0, 0 in the recipients of group 1. The above indicators were 2, 1, 3, 0, 1 in the recipients of group 2 and 10, 8,20, 1, 6 in the recipients of group 3. There was no significant difference in the above indicators among the three groups ( χ2=1.58, 0.60, 5.19, 1.62, 0.97, P>0.05). The 1-year and 3-year cumulative survival rates of the donor liver were 100.00% and 100.00% in the recipients of group 1 after liver transplantation. The above indicators were 94.74% and 77.16% in the recipients of group 2 and 91.57% and 89.30% in the recipients of group 3. There was no significant difference in the cumulative survival rate of donor liver among the three groups ( χ2=2.69, P>0.05). The 1-year and 3-year cumulative survival rates were 100.00% and 100.00% in the recipients of group 1 after liver transplantation. The above indicators were 93.74% and 77.16% in the recipients of group 2 and 89.40% and 86.00% in the recipients of group 3. There was no significant difference in the cumulative survival rate among the three groups ( χ2=1.94, P>0.05). Conclusion:Donor livers with high serum sodium level can be used in the DCD liver transplantation.

Objective To evaluate the role and potential mechanism of interleukin (IL)-18/IL-18 binding protein (BP) in mediating the killing effect of natural killer (NK)-92MI cells upon endothelial cells from α-1, 3- galactosyltransferase gene-knockout (GTKO) porcine models. Methods NK-92MI cells were divided into the NK, NK+IL-18, NK+GTKO, IL-18+NK+GTKO and IL-18+IL-18BP+NK+GTKO groups. The messenger ribonucleic acid (mRNA) levels of inflammation-related genes in NK-92MI cells were detected by quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR). The killing effect of NK-92MI cells on endothelial cells from GTKO porcine models was evaluated by lactate dehydrogenase (LDH) assay. The apoptosis of endothelial cells from GTKO porcine models was assessed by terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) assay. The expression levels of proteins with killing effect and apoptosis-related proteins were determined by Western blot. Results Compared with the NK, NK+IL-18 and NK+GTKO groups, the expression levels of interferon (IFN)-γ, tumor necrosis factor (TNF)-α, IL-8, IL-3, IL-6 and granulocyte-macrophage colony stimulating factor (GM-CSF) mRNA were up-regulated in NK-92MI cells in the IL-18+NK+GTKO group, and the differences were statistically significant (all P < 0.05). Compared with the IL-18+NK+GTKO group, the expression levels of IFN-γ, TNF-α, IL-8, IL-3, IL-6 and GM-CSF mRNA were down-regulated in NK-92MI cells in the IL-18+IL-18BP+NK+GTKO group, and the differences were statistically significant (all P < 0.05). Compared with the NK+GTKO group, the expression levels of perforin, granzyme B and IFN-γ proteins in NK-92MI cells were up-regulated, the killing rate of NK-92MI cells against endothelial cells from GTKO porcine models was enhanced, the apoptosis rate of endothelial cells from GTKO porcine models was increased, and the ratios of B cell lymphoma-2 (Bcl-2)-associated X protein (Bax)/Bcl-2 and cleaved Caspase-3/Caspase-3 in endothelial cells from GTKO porcine models were elevated in the IL-18+NK+GTKO group, and the differences were statistically significant (all P < 0.05). Compared with the IL-18+NK+GTKO group, the expression levels of perforin, granzyme B and IFN-γ proteins were down-regulated, the killing rate of NK-92MI cells against endothelial cells from GTKO porcine models was decreased, the apoptosis rate of endothelial cells from GTKO porcine models was decreased, and the ratios of Bax/Bcl-2 and cleaved Caspase-3/Caspase-3 in endothelial cells from GTKO porcine models were declined in the IL-18+IL-18BP+NK+GTKO group, and the differences were statistically significant (all P < 0.05). Conclusions IL-18BP may block the expression of inflammation-related genes in NK-92MI cells induced by IL-18 and the killing effect of NK-92MI cells on endothelial cells from GTKO porcine models.

The rapid development of gene editing technology showed usefulness of pig xenotransplantation as a donor in clinical application. Clinical trials of non-human primates using pig heart and kidney were able to survive them for a long period of time, while the longest survival of xenograft liver transplantation was nearly 1 month, which could meet the conditions for entering clinical trials for human patients. However, compared with heart and kidney transplantation, only a few units in the world can carry out xenograft liver transplantation due to the high technical difficulty and difficult perioperative management. This review summarized the advancement and progress in the field and discussed the technical characteristics and difficulties, so as to provide experience and reference for the future development of clinical trials, i.e., comparison of pig and liver anatomy, animal models of xenograft liver transplantation, and characteristics and difficulties in liver xenotransplantation technique.

Primary liver cancer has the features of high malignancy, rapid progression, frequent recurrence/metastasis, and high mortality, and therefore, most patients have developed intrahepatic or extrahepatic metastasis when attending the hospital and thus lost the opportunity for surgical treatment. Chimeric antigen receptor T-cell (CAR-T) immunotherapy has achieved good efficacy in the treatment of B-cell acute lymphoblastic leukemia, and clinical trials have been initiated to explore its applications in solid tumors such as primary liver cancer, pancreatic cancer, gastric cancer, and prostate cancer. This article reviews the efficacy of CAR-T immunotherapy in the clinical trials for primary liver cancer and discusses the difficult issues that need to be solved in clinical practice, such as the lack of suitable tumor targets, the inhibitory effect of tumor microenvironment on CAR-T cells, and the poor infiltration of CAR-T cells in tumor tissue, so as to provide a reference for related clinical studies.

Objective To investigate the application prospect of the most extensive genome engineering pig internationally in preclinical xenotransplantation. Methods Porcine endogenous retrovirus (PERV) knockout combined with 3 major heterologous antigen gene knockouts and 9 humanized genes for inhibition of complement activation, regulation of coagulation disorders, anti-inflammatory and anti-phagocytosis were transferred into a pig (PERV-KO/3-KO/9-TG) as a donor, and the heart, liver and kidney were obtained and transplanted to 3 Rhesus macaque recipients respectively to establish a preclinical research model of pig-to-Rhesus macaque xenotransplantation. The functional status of xenografts after blood flow reconstruction was observed and the survival of recipients was summarized. The hemodynamics of xenografts were monitored. The change of hematological indexes of each recipient was compared. The histopathological manifestation of xenografts was observed. Results After the blood flow was reconstructed, all xenografts showed ruddy color, soft texture and good perfusion. The transplant heart, liver and kidney showed full arterial and venous blood flow and good perfusion at 1 d after operation. The postoperative survival time of heart, liver, and kidney transplant recipients was 7, 26, and 1 d, respectively. The levels of creatine kinase, creatine kinase isoenzyme, and lactate dehydrogenase increased in heart transplant recipient at 1 d after operation, and gradually recovered to near normal levels at 6 d after operation. All indexes increased sharply at 7 d after operation. The level of aspartate aminotransferase increased in liver transplant recipients at 2 d after operation, and the alanine aminotransferase basically returned to normal at 10 d after operation, but the total bilirubin continued to increase. Both aspartate aminotransferase and alanine aminotransferase increased at 12 d after operation, and reached a peak at 15 d after operation. The kidney transplant recipient developed mild proteinuria at 1 d after operation, and died of sudden severe arrhythmia. Histopathology showed that the tissue structure of cardiac and renal xenografts was close to normal, and liver xenografts presented with patchy necrosis, the liver tissue structure was disordered, accompanied by inflammatory damage, interstitial hemorrhage and thrombotic microangiopathy. Conclusions PERV-KO/3-KO/9-TG pig shows advantages in overcoming hyperacute rejection, mitigating humoral rejection and coagulation dysregulation. However, whether it can be used as potential donor for clinical xenotransplantation needs further evaluation.

Objective:To investigate the influencing factors for hepatic artery complica-tions of liver transplantation from donation after citizen's death.Methods:The retrospective cohort study was conducted. The clinicopathological data of 147 recipients who underwent liver transplan-tation from donation after citizen's death in Xijing Hospital of Air Force Military Medical University from January 2015 to June 2020 were collected. There were 109 males and 38 females, aged (46±12)years. All recipients underwent liver transplantation from donation after citizen's death. Observation indicators: (1) surgical situations; (2) occurrence of hepatic artery complications after liver transplantation; (3) analysis of donor related influencing factors for hepatic artery complications after liver transplantation; (4) analysis of recipient related influencing factors for hepatic artery complications after liver transplantation; (5) follow-up. Follow-up was conducted using outpatient examination or telephone interview to detect survival of recipients up to June 2021. Measurement data with normal distribution were represented as Mean± SD. Measurement data with skewed distribution were represented as M(range). Univariate analysis was conducted using the Fisher exact probability, and multivariate analysis was conducted using the COX regression model. Kaplan-Meier method was used to calculate the cumulative survival rate and draw the survival curve. Results:(1) Surgical situations: of the 147 recipients, 108 cases underwent orthotopic liver transplantation, and 39 cases underwent piggyback liver transplantation. The operation time of 147 recipients was (458±101)minutes. (2) Occurrence of hepatic artery complications after liver transplantation: 4 of the 147 recipients had hepatic artery complications, including 3 cases with hepatic artery embolism and 1 case with hepatic artery stenosis. The time to occurrence of hepatic artery complications after liver transplantation was (5±2)days. (3) Analysis of donor related influencing factors for hepatic artery complications after liver transplantation: results of univariate analysis showed that age, atherosclerosis, fatty liver and arterial variation were not donor related factors influencing hepatic artery complications after liver transplantation ( P>0.05). (4) Analysis of recipient related influencing factors for hepatic artery complications after liver transplantation: results of multivariate analysis showed that insufficient hepatic artery blood flow in the recipient was an independent risk factor for hepatic artery complications after liver transplantation ( hazard ratio=10.13, 95% confidence interval as 1.05-97.42, P<0.05). (5) Follow-up: 146 of the 147 recipients were followed up for 1 to 77 months, with a median follow-up time of 34 months. The 1-year cumulative survival rate of the 146 recipients was 92.2%. Conclusion:Insufficient hepatic artery blood flow of the recipient is an independent risk factor for hepatic artery complications after liver transplantation from donation after citizen's death.

It is proven that laparoscopic sleeve gastrectomy (LSG) is effective for obesity, type 2 diabetes mellitus and other obesity-related complications. The surgical procedure of LSG is relatively simple, with few short-term or long-term complications, which has increasing be applicated in recent years. As more hospitals in China carry out LSG, the related reports of its complications have gradually increased. The most common complications of LSG include gastric leakage, bleeding, and gastric cavity stenosis. Among them, gastric leakage is a more difficult problem, and untreated or improper treatment can bring serious consequences to patients. Based on the current progress in clinical treatment of gastric leakage after LSG and practical experience, the authors summarize and discusse the clinical experience of the prevention and treatment of such patients.