Kidney xenotransplantation: status quo and development trend of physiological research / 器官移植

Organ transplantation is the most effective treatment for all categories of end-stage organ diseases. To resolve the shortage of donors in organ transplantation, widespread attention has been diverted to xenotransplantation. At present, clinicians mainly highlight the problems related to xenotransplantation rejection and viral infection. The physiology of xenotransplantation has been rarely studied. Kidney performs endocrine function by producing erythropoietin (EPO), renin and activating vitamin D. Although these pathways are usually well preserved in allogeneic transplantation, species-specific differences, especially those between pigs and non-human primates, may still affect the physiological function of transplant organs. In this article, the changes of EPO, renin-angiotensin-aldosterone system (RAAS) and active vitamin D3 of pig and human after xenotransplantation were illustrated, aiming to provide reference for subclinical research of xenotransplantation.

Pattern and Severity of Anaemia in Predialysis Chronic Kidney Disease Patients in Bangladesh: A Tertiary Care Hospital Study

Background: Anemia is a common complication in chronic kidney disease (CKD), and is associated with a reduced quality of life, and increased morbidity and mortality. The mechanisms involved in ananaemiassociated with CKD are diverse and complex. They include a decrease in endogenous erythropoietin (EPO) production, absolute and/or functional iron deficiency, and inflammation with increased hepcidin levels, among others. Objective: The objective of our study was to investigate the prevalence and severity of anaemia in pre-dialysis patients, and chronic kidney disease patients in Bangladesh.Material & Methods:This was a case-control prospective study conducted with over 300 Bangladeshi non-patients as the control group A and 87 with different stages of chronic kidney disease (CKD) patients as the case group B in the department of Nephrology BSMMU from April’2004 to June 2006. The normal people who had no history of diabetes mellitus, hypertension, or CKD and were not on any medication were controlled and different stages of the CKD patients who had no history of blood transfusion, erythropoietin and parental iron infusion were cases.Results:Out of 300 normal populations male was 158(52.7%) and the female was 142(47.3%) and the mean haemoglobin level of the male was 13.94 g/dl and the female was 12.29 g/dl. Among males 24(15.2%) and females 55(38.7%) were anaemic and the overall prevalence of anaemia was noted at 26.3%. Of the total anaemic people, 25% was microcytic anemia. Out of 87 CKD patients, 56 (64%) were male and 31 (36%) were female. The overall prevalence of anaemia in CKD patients was 95.4%. The haemoglobin level was <11g/dl in 57.14% patients with CCr 30-59 ml/min/1.73m2 which increases to 87.5 % in patients with CCr 15-29 ml/min/1.73m2, which also increases to 94.2 % in patients with CCr<15 ml/min/1.73m2. Mean haemoglobin was observed at 8.6 g/dl, 9.54 g/dl and 11.25 g/dl in stage V, stage IV and stage III CKD patients respectively. Anaemia appeared at 43.53 ml/min/1.73 m2 of CCR.Conclusions:The results demonstrate that patient with reduced renal function is more likely to have anaemia and the prevalence and severity of anaemia increase with declining kidney function. CCr and TSAT is the important predictor of anaemia. In a significant number of the CKD, patient anaemia was associated with iron deficiency.

Technical specification for clinical diagnosis and treatment of human parvovirus B19 infection in kidney transplant recipients (2022 edition) / 器官移植

Long-term use of immunosuppressant in kidney transplant recipients leads to poor immune function and infection with various pathogens. In recent years, along with the advancement of detection technique of human parvovirus B19 (HPV-B19) infection and the increasing quantity of kidney transplantation, the infection rate of HPV-B19 after kidney transplantation has been elevated year by year, becoming one of the major causes of pure red cell aplasia (PRCA), affecting the recovery of renal allograft function, and even leading to the injury or poor prognosis of renal allograft. To further standardize the diagnosis and treatment of HPV-B19 infection in kidney transplant recipients, Branch of Organ Transplantation of Chinese Medical Association and National Kidney Transplantation Quality Control Center jointly organized experts to formulate the clinical diagnosis and treatment specification for HPV-B19 infection after kidney transplantation from the perspectives of etiology, epidemiological characteristics, clinical manifestations, diagnosis, prevention, treatment, existing problems and prospects of HPV-B19, aiming to provide guidance for standardized prevention and treatment of HPV-B19 infection post-kidney transplantation in China.

Expression and significance of EPO and HIF-1α in serum and aqueous humor of patients with acute anterior uveitis / 国际眼科杂志(Guoji Yanke Zazhi)

@#AIM: To detect the expression of erythropoietin(EPO)and hypoxia-inducible factor-1α(HIF-1α)in serum and aqueous humor of patients with acute anterior uveitis(AAU), and to explore their clinical significance. <p>METHODS: From January 2018 to December 2020, 60 patients with AAU in our hospital were prospectively selected as the research objects, and 60 patients with proliferative vitreoretinopathy in the same period were taken as control(control group). The serum and aqueous humor of two groups were collected, enzyme-linked immunosorbent assay(ELISA)was used to detect the levels of EPO and HIF-1α in serum and aqueous humor; the self-rating anxiety scale(SAS)and the self-rating depression scale(SDS)were used to evaluate the AAU patients, and the severity of the disease was scored; Pearson method was used to analyze the correlation between SAS score, SDS score and levels of EPO and HIF-1α in serum and aqueous humor, and the correlation between levels of EPO and HIF-1α in the serum and aqueous humor. Spearman was used to analyze the correlation between the disease severity score of AAU patients and the levels of EPO and HIF-1α in serum and aqueous humor. <p>RESULTS: Compared with the control group, the levels of EPO and HIF-1α in the serum and aqueous humor of the study group were higher(<i>P</i><0.01). Among AAU patients, 23 were negative of SAS score and 37 were positive, and 29 were negative of SDS score and 31 were positive. Compared with patients with negative SAS score, the level of HIF-1α in serum and the level of EPO in the aqueous humor were higher in patients with positive SAS score(<i>P</i><0.05); compared with patients with negative SDS score, the level of EPO in serum and the levels of EPO and HIF-1α in aqueous humor were higher in patients with positive SDS score(<i>P</i><0.01). There were 26 mild patients and 34 severe patients with AAU. Compared with mild patients with AAU, the levels of EPO and HIF-1α in serum and aqueous humor were increased in severe patients(<i>P</i><0.01). Pearson analysis showed that the SAS and SDS scores of AAU patients were not significantly correlated with the levels of EPO and HIF-1α in serum and aqueous humor(<i>P</i>>0.05), there was a positive correlation between EPO and HIF-1α in serum(<i>P</i><0.05), and between EPO and HIF-1α in aqueous humor(<i>P</i><0.05). Spearman analysis showed that the disease severity score of AAU patients was positively correlated with the levels of EPO and HIF-1α in serum and aqueous humor(<i>P</i><0.05). <p>CONCLUSION: EPO and HIF-1α are highly expressed in serum and aqueous humor of AAU patients, and they are closely related. The two are closely related to the disease severity score, and should be paid attention to clinically.

Changes of EPO in rats with chronic renal failure and low immunity and reversal effects of Yougui Yin and exogenous EPO / 中国中药杂志

The aim of this paper was to observe the changes of EPO in rats with chronic renal failure and low immunity induced by adenine and to investigate the reversal effect of Yougui Yin(YGY)and exogenous EPO.SD rats were randomly divided into normal control group(n=20)and adenine-model group(n=90).The adenine-model group rats were given with adenine 150 mg·kg~(-1)for 14days by gavage administration,and then randomly divided into 8 groups as follows:model group(n=20),YGY groups(10,20,40 g·kg~(-1),10 in each group),rh EPO group(500,1 000,1 500 IU·kg~(-1),10 in each group),and Guilu Erxian Gao 10 g·kg~(-1)group(positive control group,n=10).From the 15th day,every group except normal control group received 150 mg·kg~(-1)adenine by gavage administration once every two days to maintain the model.Meanwhile,the rats in each YGY group and Guilu Erxian Gao group received corresponding drugs by gavage administration once a day for 30 days.The rats in rh EPO groups were subcutaneously injected with rh E-PO once every 3 days for 30 days.On day 46,rats were anesthetized to take blood and then sacrificed.The serum levels of creatinine,urea,glandular hormone,immunoglobulin,complement and interleukin,the proportion of T cells in the spleen,the killing rate of NKcells and the proliferative capacity of spleen cells were measured.Western blot was used to detect the key proteins in JAK2-STAT5 and NF-κB pathways mediated by EPO in kidney and spleen.As compared with the normal control group,the serum levels of CREA and UREA were increased significantly and the serum levels of ACTH,T and T3 were decreased significantly in the model group rats,indicating that the functions of kidney,adrenal gland,gonad and thyroid in rats were decreased.At the same time,the serum levels of Ig A,Ig G,Ig M,C3,C4,IL-2 and IL-6 were significantly decreased,the proportion of CD4~+,CD4~+/CD8~+T cell subsets,the killing rate of NK cell and the proliferation ability of spleen lymphocyte in spleen of the model group rats were significantly declined,indicating that the immune function of model group rats was decreased,and the model of kidney deficiency immunodeficiency was successfully constructed.As compared with the model group,both YGY and rh EPO significantly reduced serum levels of CREA and UREA,significantly increased serum levels of ACTH,T,T3,T4,Ig A,Ig G,Ig M,C3,C4,IL-2,and IL-6,increased the proportion of CD4~+,CD4~+/CD8~+T cell subsets,the killing rate of NK cell and the proliferation ability of spleen lymphocyte in spleen.YGY could significantly increase the content of EPO in serum.Both YGY and rh EPO could regulate the expression of EPOR,p-JAK2/JAK2,STAT5,NF-κB p50,NF-κB p65 and NF-κB IκB of EPO-mediated JAK2-STAT5 and NF-κB pathways in kidney and spleen.EPO is an important factor in the chronic renal failure and low immunity induced by adenine in rats.Exogenous EPO and YGY have significant reversal effects for the model rats.The mechanism of YGY may be related to the up-regulation of EPO in serum and regulating the expression of key proteins in EPO-mediated JAK2-STAT5 and NF-κB pathways in kidney and spleen.The mechanism of exogenous EPO may be related to regulating the expression of the key proteins in EPO-mediated JAK2-STAT5 and NF-κB pathways in kidney and spleen.

Preliminary study of the effect of EPO pretreatment of bone marrow mesenchymal stem cells on preventing acute rejection after renal transplantation in rats / 器官移植

Objective To investigate the role of bone marrow mesenchymal stem cells (BMSCs) pretreated with erythropoietin (EPO) in the prevention of acute rejection after renal transplantation in rats. Methods BMSCs were divided into five groups: control group (without EPO), group A (pretreated with EPO at a final concentration of 10 IU/mL), group B (pretreated with EPO at a final concentration of 100 IU/mL), group C (pretreated with EPO at a final concentration of 500 IU/mL) and group D (pretreated with EPO at a final concentration of 1 000 IU/mL). In each group, the BMSCs were cultured for 24 h and 48 h. The proliferation rate of the BMSCs was determined by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) assay. The BMSCs were divided into two groups: BMSC group (without EPO) and EPO-BMSC group (pretreated with EPO at a final concentration of 500 IU/mL). After 48 h culture, Western blot was adopted to measure the expression level of CXC chemokine receptor (CXCR) 4 protein in BMSCs. Wistar rats were used as the donors, and SD rats were utilized as the recipients to establish the rat models with acute rejection after renal transplantation. The recipient rats were randomly divided into four groups (n=6 in each group) including the control group (without any intervention), EPO group (injection of 1 mL of solution containing 500 IU EPO via tail vein immediately after surgery), BMSC group (injection of 1 mL of solution containing 1×106/mL BMSCs via tail vein immediately after surgery) and EPO-BMSC group (injection of 1 mL of solution containing 1×106/mL BMSCs cultured in vitro with 500 IU/mL EPO via tail vein). The level of serum creatinine (Scr) level was determined by Scr detection kit. Western blot was used to detect the expression levels of interferon (IFN)-γ and interleukin (IL)-4 proteins. Results After 24 h culture, the proliferation rate of BMSCs did not significantly differ among all groups (all P>0.05). After 48 h culture, the proliferation rate of BMSCs in group C (pretreated with EPO at a final concentration of 500 IU/mL) was significantly higher than that in the control group (P<0.05). Compared with the BMSC group, the expression level of CXCR4 protein on the surface of BMSCs was higher in the EPO-BMSC group (P<0.05). At 1 d after renal transplantation, the levels of Scr did not significantly differ among all groups (all P>0.05). At 5 d after operation, the levels of Scr in the EPO, BMSC and EPO-BMSC groups were significantly lower than that in the control group (all P<0.05). The level of Scr in the EPO-BMSC group was markedly lower than those in the EPO and BMSC groups (both P<0.05). At postoperative 1 d and 5 d, the expression levels of IL-4 protein in the kidney tissues did not significantly differ among all groups (all P>0.05). At 1 d after surgery, compared with control group, the expression levels of IFN-γ protein and IFN-γ/IL-4 ratio in the renal tissues in the EPO, BMSC and EPO-BMSC groups were significantly decreased to varying extents (all P<0.05), and similar results were obtained at 5 d after surgery (all P<0.05). The expression levels of IFN-γ protein and IFN-γ/IL-4 ratio in the EPO-BMSC group were significantly lower than those in the EPO group and BMSC group (both P<0.05). Conclusions BMSCs pretreated with EPO can prevent the incidence of acute rejection after renal transplantation and protect the renal graft function.

Therapeutic effect of L-carnitine combined with erythropoietin and iron on renal anemia in rats / 中国比较医学杂志

Objective To investigate the therapeutic effect of L-carnitine combined with erythropoietin (EPO) and iron on renal anemia in rats. Methods The renal anemia rat model was established using adenine. All rats were randomly divided into three groups: control group (group A), EPO combined with iron group (group B), and L-carnitine combined with EPO and iron treatment group (group C). The levels of red blood cells (RBC), hemoglobin (Hgb), hematocrit (Hct), C-reactive protein (CRP), Fe in peripheral blood (Fe), serum ferritin (SF) and transferrin saturation (TS) were measured. Pathological changes in the kidney, liver and small intestine tissues were examined using HE staining. Results Compared with the group A, the levels of RBC, Hgb, Hct, Fe, SF, and TS were significantly increased, however, the level of CRP significantly decreased in the groups B and C (P＜ 0. 05). In the group C, the levels of RBC, Hgb, and CRP was higher than the group B (P＜ 0. 05). Furthermore, the pathological changes in the kidney, liver and small intestine tissues were improved in the groups B and C. Conclusions L-carnitine combined with EPO and iron has a therapeutic effect on renal anemia in rats, thus, it deserves further studies and application.

Synthesis and biological evaluation of 125I-erythropoietin as a potential radiopharmaceutical agent for tumours

Erythropoietin (EPO) is a glycoprotein hormone responsible for regulating erythropoiesis. Expression of EPO and EPO receptors (EPOr) has recently been demonstrated in some neoplastic cell lines and tumours, suggesting a potential new target for therapy. In this work, EPO was labeled with iodine-125 using the lactoperoxidase method, known to prevent damage to protein during radioiodination, and labeling conditions were optimized. In vitro stability studies have shown that 125I-EPO is radiochemically stable for 20 days after radiolabeling. In vitro cell binding studies have demonstrated very low binding (<2 percent) of EPO to normal and neoplastic cell lines tested. As expected, the biodistribution in healthy mice exhibited comparatively high rates of fixation in the organs of the excretory system. Thyroid also proved to be a critical organ which may indicate in vivo dissociation of 125I-EPO. In mice with induced melanoma, only a residual fixation in the tumour was evident. Further studies are warranted on other tumoral cell lines to better understand the binding process and internalization into cells. Studies on EPO labeled with carbon-11 could be valuable, since there is a greater chance of preserving the biological activity of the protein using this method.

A eritropoetina (EPO) é um hormônio glicoprotéico responsável pela regulação da eritropoese. Recentemente foi demonstrado que os receptores de EPO (EPOr) estão expressos em algumas linhas celulares neoplásicas, o que sugere a sua potencialidade como um novo alvo terapêutico. Neste trabalho a EPO foi radiomarcada com iodo-125 através do método da lactoperoxidase, menos agressivo para a viabilidade biológica das proteínas. A 125I-EPO revelou ser radioquimicamente estável durante 20 dias após a síntese. Um estudo biológico in vitro em linhas celulares tumorais demonstrou que a 125I-EPO apresenta uma ligação muito fraca (<2 por cento), tanto em células normais como nas linhagens tumorais testadas. A biodistribuição em camundongos saudáveis apresentou taxas de fixação relativamente maiores nos órgãos excretores e a tireóide revelou ser o órgão crítico, o que pode indicar a dissociação in vivo da 125I-EPO. No estudo em camundongos com melanoma induzido a fixação no tumor foi residual. Serão, no entanto, necessários novos estudos em outras linhagens tumorais para entender o seu processo de internalização e ligação nas células. Estudos da EPO radiomarcada com carbono-11 poderão também revelar-se interessantes, já que neste método há maior probabilidade da atividade biológica ser preservada.

Influence of Erythropoietin and Inflammatory Cytokines on Pathogenesis of Cerebral Palsy / 中国康复理论与实践

@#Objective To investigate the effect of erythropoietin(EPO)as a brain-protective factor and inflammatory cytokines in the pathogenesis of cerebral palsy(CP).Methods Serum samples from 31 CP patients,37 neonates with CP risk factors such as hypoxic-ischemic injury and/or perinatal infection,and 20 controls of neonates or children were obtained respectively.EPO,tumor necrosis factor(TNF)-α and interleukin(IL)-6 levels were measured with the enzyme-linked immunosorbent assay double sandwich method(ABC-ELISA).Results The serum EPO level of neonatal patients was higher than that of controls or CP group(P<0.01),but there was no significant difference between CP group and controls.The serum TNF-α and IL-6 levels of CP and neonatal patients were higher than that in controls(P<0.01).The serum TNF-α level of CP group was higher than that of neonatal patients(P<0.05).There was no significant difference between CP group and neonatal patients in serum IL-6 level.Conclusion The inflammatory responses mediated by proinflammatory cytokines may play a role in the pathogenesis of cerebral palsy.

Effects of Intermittent Hypoxic Exposure on the Production of Erythrocyte and Some Haematopoietic Factor in Rats with Exercise-Induced Anemia / 中国运动医学杂志

0.05).Conclusion The hypoxic exposure can accelerate the production of erythrocyte, and treat the exercise-induced anemia effectively. Improvement of some haematopoietic factors and enhancement of hematopoiesis in marrow is thought to be the possible mechanism.

In vivo Erythropoietin Delivery Using Lentiviral Vector in Rats / 대한혈액학회지

BACKGROUND: Erythropoietin (EPO) is a 30.4kDa glycoprotein that serves as the primary regulator of red cell production in mammals. Recombinant erythropoietin has been used in the treatment of anemia associated with numerous chronic diseases. Ex vivo therapy of recombinant EPO, however, requires large dose and frequent administration, which gives financial impact to the patients. In vivo delivery of EPO using gene therapy method can solve this problem. METHODS: Recombinant lentiviral vectors containing the rat EPO gene were made by co-transfection of 293T cell with pRRL-cPPT-CMV-EPO-PRE-SIN, pMDL, pVSVG, and pREV plasmids. These viruses were concentrated and intramusculary injected into the groin muscles of Fisher 344 rats. Sequential complete blood counts were measured periodically thereafter. RESULTS: Virus doses of 6x107 infectious units and 6x106 infectious units produced significantly increased hemoglobin and hematocrit values, being 24.9+/-0.19g/dL, 66.9+/-0.62% (P < 0.01, N=5) and 18.4+/-0.55g/dL, 54.6+/-1.71%(P < 0.01, N=5), respectively at 40 weeks after injection, over values of control animals receiving normal saline (15.2+/-0.42g/dL, 44.6+/-0.49%, N=5). CONCLUSION: Lentiviral vectors are able to transduce skeletal muscle and are capable of achieving sustained expression and systemic delivery of EPO following intramuscular administration. Gene therapy using lentiviral vectors may provide a practical strategy for in vivo delivery of therapeutic proteins.

Effects of oxygen on rabbits during exposure to high altitude / 解放军医学杂志

Objective To observe physiological and ultrastructure changes in rabbits breathing various contents of oxygen during exposure to high altitude. Methods Twenty healthy rabbits were randomly divided into air-breathing group, 63% oxygenbreathing group, 83% oxygenbreathing group and pure oxygen breathing group. All rabbits were exposed to an atmosphere corresponding to an altitude of 11 000m in hypobaric chamber for 30min. The amount of air bubble in the heart and ECG of rabbits were recorded, the ultrastructural changes in the heart and brain were examined, and the expression of kidney erythopoietin (EPO) was also observed. Results The amount of air bubbles in the air breathing group was increased remarkably, and most of the rabbits developed arrhythmia. With the increase of oxygen concentration, the changes in ultrastructure were alleviated and the expression of kidney EPO decreased. Conclusion Oxygenconcentration above 80% could provide obvious protection for rabbits during their exposure to high altitude.

The Effect of Recombinant Human Erythropoietin on Postoperative Anemia in Cardiac Surgery Patients / 临床麻醉学杂志

Objective:To observe the change of endogenous erythropoietin(EPO) in patients undergoing elective major surgeries and the impact of recombinant human erythropoietin(rhEPO) on blood viscosity of animalsunder normal physiologic al conditions. In addition, the effect of rhEPO on postoperative anemia in cardiac surgery patients was evaluated. Methods:Ten patients scheduled for elective major procedures were studied. Included criteria were no preoperative anemia, moderate intraoperative blood loss and no postoperative transfusion. Serum EPO levers were measured prior to operation, immediately after the operation, as well as on postoperative days(PODs) 1, 2, 4, 6, 8. The change of Hct was measured too. (EPO group) Six adult rabbits received 300IU/kg of rhEPO weekly for two weeks. Specimens of Hb, Hct, RBC, serum ALT, serum potassium and blood viscosity were obtained before, during and after administration of rhEPO. Six patients with postoperative anemia (Hb＜100g/L) who underwent cardiac surgeries received 300IU/kg of rhEPO weekly for two weeks. The changes of Hb,Hct were compared(rhEpO group). Results: In EPO group serum EPO concentration increased immediately after the operation, reached a peak level during 24-48h postoperatively and remained significantly elevated above the operative value until POD 8. Hct significantly declined after the operation and was still significantly lower than the preoperative value on POD 8.On the 12th day after applying rhEPO, Hb, Hct and RBC of the rabbits were increased significantly, (P＜0.01 ) but serum ALT, potassium and blood viscosity did not changed significantly. In rhEPO group, Hb, Hct increased significantly on the 14 days after applying rhEPO. Conclusion: It is effective and safe to treat postoperative anemia with a high dose of rhEPO in patients undergoing cardiac procedures. The administration of rhEPO corrects postoperative anemia quickly, then precludes many complications related to decrease oxygen delivery capacity.