Objective To establish a method for acquisition, perfusion, preservation and transportation of the genetically modified pig kidneys. Methods An eight genetically modified pig was utilized as experimental subject. Prior to kidneys procurement, the health status of the pig was assessed through hematology examination, and the vascular structure of the kidneys was examined using imaging techniques. Following kidneys acquisition, the pig kidneys were perfused and subsequently packaged into the cryogenic storage container labeled "For Organ Transportation Only" for interprovincial transport after communicating the transportation process with transportation department. To evaluate pathological damage to the pig kidneys, a serious of methods were employed such as hematoxylin-eosin (HE) staining, real-time fluorescent quantitative polymerase chain reaction (RT-qPCR), terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) fluorescence staining and enzyme-linked immune absorbent assay (ELISA). Results The preoperative examination of the eight genetically modified pig showed that the serum creatinine was 73.2 μmol/L, blood urea nitrogen was 2.8 mmol/L and hemoglobin was 116 g/L, all within the normal range, indicating normal renal function. CT angiography revealed no lesions in the pig kidneys, and no dilation, stenosis or premature branching of the blood vessels. The total time of obtaining the left and right kidneys from the eight genetically modified pig was (125 ± 10) min, with a blood loss of (20 ± 2) mL. The warm ischemia times were 3 min and 7 min, respectively. The perfusion and trimming times of the left and right kidneys were 36 min and 41 min, respectively. After perfusion, both kidneys were white and moist. The cold preservation and transportation time was 8 h. HE staining showed that some glomeruli were shrunk, and the lumens of the surrounding renal tubules were slightly depressed and swollen with partial inner membrane shedding and microvacuoles formed when the kidneys were preserved for 8 h. The level of cysteinyl aspartate-specific proteinase-3 messenger RNA in the kidneys tissue gradually increased with the extension of cold preservation time after 2 h (P<0.05). TUNEL fluorescence staining showed that only a small number of cells underwent apoptosis after 8 h of cold preservation, which was not significantly different from that at 0 h (P>0.05). ELISA results showed that the contents of lactate dehydrogenase (LDH) and creatinine in the preservation solution remained relatively stable, but the content of kidney injury molecule 1 (KIM-1) gradually increased with the extension of preservation time, suggesting that the pig kidneys had mild injury. Conclusions By establishing methods for acquisition, perfusion, preservation and transportation of the kidneys from genetically modified donor pig, it is possible to effectively and reliably use genetically modified pig kidneys for xenotransplantation.

Lung transplantation is the ultimate therapeutic option for end-stage pulmonary diseases such as interstitial pneumonia, chronic obstructive pulmonary disease and pneumoconiosis. Currently, the shortage of allogeneic lung donors significantly limits the opportunity for end-stage lung disease patients to receive lung transplantation. In recent years, with the rapid development of biomedical engineering technologies, especially the major breakthroughs in genetic modification and cloning, xenogeneic lung transplantation has shown important potential for clinical translation. Among them, genetically modified pigs have become the most promising xenogeneic lung source due to the close similarity of organ size and physiological characteristics to humans, and the ability to perform targeted gene knockouts (such as α-Gal antigen knockout) to reduce the occurrence of hyperacute rejection. This article focuses on the research progress of porcine xenogeneic lung transplantation, systematically reviews the latest achievements and challenges in animal experiments and human trials, and introduces the technical experience accumulated by Shenzhen Third People's Hospital in the porcine-to-monkey xenogeneic lung transplantation model, in the hope of providing practical references for future research in this field.

Objective To construct a Type 1 diabetes model in miniature pigs and explore postoperative care strategies for effectively prolonging the survival time of the model pigs.Methods Seven Banna miniature pigs were selected for pancreatectomy.Glucose,vitamins,and antibiotics were administered for 3-5 days after surgery to aid recovery.Blood glucose and urine glucose levels were measured twice a day in the morning and evening to adjust insulin supplementation accordingly.The model pigs were observed daily and records were kept,including orexis,psychosis,weakness,skin ulcer,and feces and urine.Body weight was measured weekly until the death of the model animals.Based on the model pigs'condition,glucose injection and Ringer's lactate solution were administered to supplement nutrition and correct electrolyte imbalances.Results All seven Banna miniature pigs showed typical symptoms of diabetes:random blood glucose levels higher than 11.1 mmol/L after pancreatectomy,far exceeding the average blood glucose level of 6.0 mmol/L in normal pigs;positive urine glucose;and progressive weight loss.These features indicated the successful construction of Type 1 diabetes model.Additionally,Type 1 diabetic pigs that survived more than 8 weeks showed progressive hair loss and skin ulceration.Euthanasia was performed on model pigs when they were unable to stand or even eat independently,and pathological examination and HE staining were conducted on tissues collected from affected organs such as the liver,kidneys,and skin.Pathological sections revealed liver congestion,massive glycogen accumulation,ballooning degeneration of hepatocytes,and progressive liver fibrosis,along with glomerular congestion,vacuolar degeneration in renal tubular epithelial cells,proteinuria,dermal congestion,thinning of vascular walls,and varying degrees of parakeratosis and dyskeratosis in the liver,kidneys,and skin tissues due to prolonged hyperglycemia.The average survival time of the constructed Banna miniature pig diabetes model was 44 d,with a maximum survival time of 121 d.Conclusion Type 1 diabetes model can be constructed successfully in Banna miniature pigs through pancreatectomy.With meticulous postoperative care,a long-term Type 1 diabetes model with significant complications can be achieved,providing a stable large-animal model for Type 1 diabetes treatment strategies.

Increasing studies have shown that endothelial progenitor cel s can not only promote the damaged endothelial cel s and vascular repair in ischemic brain tissue, but also promote neurogenesis, and thus promote neurological function recovery. Endothelial progenitor cel s transplantation may become an effective approach for the treatment of ischemic stroke.

AIM: To investigate the correlation between the expression of neuron-specific protein and apoptosis in the process of differentiation from rat bone marrow stromal cells into neuron with brain-derived neurotrophic factor (BDNF). METHODS: The 5th passage MSCs were induced by BDNF and 2-mercaptoethanol (?-ME), respectively. At 1 h, 6 h, 12 h and 24 h, nestin, neuron specific enolase (NSE), microtubulease associated protein (MAP)-2 and glail fibrillary acidic protein (GFAP) were detected by Western blotting. Cell cycle and apoptosis were examined by flow cytometry. RESULTS: Nestin and NSE of neuron-like cells induced by BDNF and ?-ME were all positive by Western blotting. At 12 h, nestin and NSE turned to negative and apoptosis was detected in ?-ME group, nestin and NSE still positive and apoptosis wasn't detected in BDNF group. Till 24 h, nestin and NSE in BDNF group were negative but apoptosis still not detected. Notably, GFAP (glial astrocyte marker) was detected and MAP-2 wasn't detected in the two induced groups. CONCLUSION: The down-expression of neuron-specific protein correspondingly with apoptosis in the process of differentiation from MSCs into neuron with ?-ME shows that apoptosis may be one of the causes of induced cell death. BDNF induction was not the cause of apoptosis. Other factors may include for the cell death in the presence of neuron-specific protein expression induced by BDNF.