Development and validation of a novel nomogram model for predicting delayed graft function in deceased donor kidney transplantation based on pre-transplant biopsies.

BACKGROUND: Delayed graft function (DGF) is an important complication after kidney transplantation surgery. The present study aimed to develop and validate a nomogram for preoperative prediction of DGF on the basis of clinical and histological risk factors. METHODS: The prediction model was constructed in a development cohort comprising 492 kidney transplant recipients from May 2018 to December 2019. Data regarding donor and recipient characteristics, pre-transplantation biopsy results, and machine perfusion parameters were collected, and univariate analysis was performed. The least absolute shrinkage and selection operator regression model was used for variable selection. The prediction model was developed by multivariate logistic regression analysis and presented as a nomogram. An external validation cohort comprising 105 transplantation cases from January 2020 to April 2020 was included in the analysis. RESULTS: 266 donors were included in the development cohort, 458 kidneys (93.1%) were preserved by hypothermic machine perfusion (HMP), 96 (19.51%) of 492 recipients developed DGF. Twenty-eight variables measured before transplantation surgery were included in the LASSO regression model. The nomogram consisted of 12 variables from donor characteristics, pre-transplantation biopsy results and machine perfusion parameters. Internal and external validation showed good discrimination and calibration of the nomogram, with Area Under Curve (AUC) 0.83 (95%CI, 0.78-0.88) and 0.87 (95%CI, 0.80-0.94). Decision curve analysis demonstrated that the nomogram was clinically useful. CONCLUSION: A DGF predicting nomogram was developed that incorporated donor characteristics, pre-transplantation biopsy results, and machine perfusion parameters. This nomogram can be conveniently used for preoperative individualized prediction of DGF in kidney transplant recipients.

Defining the biogeographical map and potential bacterial translocation of microbiome in human 'surface organs'.

The microbiome in a specific human organ has been well-studied, but few reports have investigated the multi-organ microbiome as a whole. Here, we aim to analyse the intra-individual inter-organ and intra-organ microbiome in deceased humans. We collected 1608 samples from 53 sites of 7 surface organs (oral cavity, esophagus, stomach, small intestine, appendix, large intestine and skin; n = 33 subjects) and performed microbiome profiling, including 16S full-length sequencing. Microbial diversity varied dramatically among organs, and core microbial species co-existed in different intra-individual organs. We deciphered microbial changes across distinct intra-organ sites, and identified signature microbes, their functional traits, and interactions specific to each site. We revealed significant microbial heterogeneity between paired mucosa-lumen samples of stomach, small intestine, and large intestine. Finally, we established the landscape of inter-organ relationships of microbes along the digestive tract. Therefore, we generate a catalogue of bacterial composition, diversity, interaction, functional traits, and bacterial translocation in human at inter-organ and intra-organ levels.

Donor-specific antibodies, glomerulitis, and human leukocyte antigen B eplet mismatch are risk factors for peritubular capillary C4d deposition in renal allografts.

BACKGROUND: The complement system plays an important role in the immune response to transplantation, and the diagnostic significance of peritubular capillary (PTC) C4d deposition (C4d+) in grafts is controversial. The study aimed to fully investigate the risk factors for PTC C4d+ and analyze its significance in biopsy pathology of kidney transplantation. METHODS: This retrospective study included 124 cases of kidney transplant with graft biopsy and donor-specific antibody (DSA) testing from January 2017 to December 2019 in a single center. The effects of recipient pathological indicators, eplet mismatch (MM), and DSAs on PTC C4d+ were examined using univariate and multivariate logistic regression analyses. RESULTS: In total, 35/124 (28%) were PTC C4d+, including 21 with antibody-mediated rejection (AMR), eight with renal tubular injury, three with T cell-mediated rejection, one with glomerular disease, and two others. Univariate analysis revealed that DSAs (P < 0.001), glomerulitis (P < 0.001), peritubular capillaritis (P < 0.001), and human leukocyte antigen (HLA) B eplet MM (P = 0.010) were the influencing factors of PTC C4d+. According to multivariate analysis, DSAs (odds ratio [OR]: 9.608, 95% confidence interval [CI]: 2.742-33.668, P < 0.001), glomerulitis (OR: 3.581, 95%CI: 1.246-10.289, P = 0.018), and HLA B eplet MM (OR: 1.166, 95%CI: 1.005-1.353, P = 0.042) were the independent risk factors for PTC C4d+. In receiver operating characteristic curve analysis, the area under the curve was increased to 0.831 for predicting PTC C4d+ when considering glomerulitis, DSAs, and HLA B eplet MM. The proportions of HLA I DSAs and PTC C4d+ in active antibody-mediated rejection were 12/17 and 15/17, respectively; the proportions of HLA class II DSAs and PTC C4d+ in chronic AMR were 8/12 and 7/12, respectively. Furthermore, the higher the PTC C4d+ score was, the more serious the urinary occult blood and proteinuria of recipients at the time of biopsy. CONCLUSIONS: PTC C4d+ was mainly observed in AMR cases. DSAs, glomerulitis, and HLA B eplet MM are the independent risk factors for PTC C4d+.

Different roles of bortezomib and ONX 0914 in acute kidney injury.

Proteasome inhibitor bortezomib offers one more option for acute or chronic antibody-mediated rejection after kidney transplantation, but aggravated acute kidney injury (AKI) in some cases early after surgery using bortezomib bring new problem. Here, we evaluated the effects of bortezomib and ONX-0914 on renal tubule injury in a mouse model of ischemia-reperfusion injury. After treated with bortezomib, serum creatinine, usea nitrogen and tubular necrosis significantly increased compared with vehicle-treated mice, but decreased in ONX-0914 group mildly. Infiltration of neutrophil and macrophage were less in bortezomib and ONX-0914-treated mice than vehicle-treated group, and the same was observed on oxidative stress in the kidneys. Furthermore, the apoptosis of renal tubular epithelial cells increased in bortezomib-treated mice' kidneys compared with ONX-0914 and vehicle-treated controls. In vitro HK2 cell experiments also demonstrated the proapoptotic effect of bortezomib. The mRNA expression of several proapoptotic factors increased in kidneys of bortezomib-treated mice. In brief, bortezomib, as a proteasome inhibitor, shows a certain cytotoxicity to renal tubular epithelial cell during ischemia/reperfusion injury (IRI) through increased apoptosis. ONX-0914, as an immunoproteasome inhibitor, showed equal potency on anti-inflammation and oxidative stress relieving compared with bortezomib, while less cytotoxicity. The results render the immunoproteasome is a better target for anti-rejection and protecting kidney function in the field of organ transplantation.

Prediction of kidney transplant outcome based on different DGF definitions in Chinese deceased donation.

BACKGROUND: Delayed graft function (DGF) is an important complication of kidney transplantation and can be diagnosed according to different definitions. DGF has been suggested to be associated with the long-term outcome of kidney transplantation surgery. However, the best DGF definition for predicting renal transplant outcomes in Chinese donations after cardiac death (DCDs) remains to be determined. METHOD: A total of 372 DCD kidney transplant recipients from June 2013 to July 2017 in the First Affiliated Hospital of Xi'an Jiaotong University were included in this retrospective study to compare 6 different DGF definitions. The relationships of the DGF definitions with transplant outcome were analyzed, including graft loss (GL) and death-censored graft loss (death-censored GL). Renal function indicators, including one-year estimated glomerular filtration rate (eGFR) and three-year eGFR, and were compared between different DGF groups. RESULTS: The incidence of DGF varied from 4.19 to 35.22% according to the different DGF diagnoses. All DGF definitions were significantly associated with three-year GL as well as death-censored GL. DGF based on requirement of hemodialysis within the first week had the best predictive value for GL (AUC 0.77), and DGF based on sCr variation during the first 3 days post-transplant had the best predictive value for three-year death-censored GL (AUC 0.79). Combination of the 48-h sCr reduction ratio and classical DGF can improve the AUC for GL (AUC 0.85) as well as the predictive accuracy for death-censored GL (83.3%). CONCLUSION: DGF was an independent risk factor for poor transplant outcome. The combination of need for hemodialysis within the first week and the 48-h serum creatinine reduction rate has a better predictive value for patient and poor graft outcome.

B-Cell Activating Factor Predicts Acute Rejection Risk in Kidney Transplant Recipients: A 6-Month Follow-Up Study.

B cell activating factor (BAFF) belonging to TNF family is a cytokine that enhances B-cell proliferation and differentiation. Recently, It has been suggested that BAFF might be a potential therapeutic target for treating autoimmune disease. However, the relationship between BAFF and allograft rejection is controversial, and the clinical significance of BAFF in predicting allograft rejection need to be further explored. We conducted 6-month follow-up study to confirm the hypothesis that BAFF might be a risk factor for predicting acute rejection in kidney transplant recipients. At the end of the study, a total of 155 kidney transplant recipients were recruited from October 2015 to October 2017, and classified into acute rejection group (n = 34) and stable renal function group (n = 121) according to their clinical course. We demonstrate that the serum BAFF levels when acute rejection occurred was significantly higher than that in the stable renal function group (2426.19 ± 892.19 vs. 988.17 ± 485.63 pg/mL, P < 0.05). BAFF expression was significantly enhanced in the membrane and cytoplasm of renal tubule epithelial cells in the transplant kidney tissue with acute rejection, and a positive correlation between BAFF and C4d expression was also observed (r = 0.880, P = 0.001). ROC analyses highlight the superiority of serum BAFF level before transplant over those on other post-transplant days in prediction of acute rejection episodes. The sensitivity, specificity and AUC (area under curve) were 83.3, 89.5, and 0.886%, respectively. Kaplan-Meier survival analysis showed that recipients with higher pretransplant BAFF levels had higher acute rejection incidence (P = 0.003). In conclusion, we have identified that BAFF levels are associated with the acute rejection and could be a promising biomarker to predict kidney transplant rejection risks.

Predictive Score Model for Delayed Graft Function Based on Hypothermic Machine Perfusion Variables in Kidney Transplantation.

BACKGROUND: Hypothermic machine perfusion (HMP) is being used more often in cardiac death kidney transplantation; however, the significance of assessing organ quality and predicting delayed graft function (DGF) by HMP parameters is still controversial. Therefore, we used a readily available HMP variable to design a scoring model that can identify the highest risk of DGF and provide the guidance and advice for organ allocation and DCD kidney assessment. METHODS: From September 1, 2012 to August 31, 2016, 366 qualified kidneys were randomly assigned to the development and validation cohorts in a 2:1 distribution. The HMP variables of the development cohort served as candidate univariate predictors for DGF. The independent predictors of DGF were identified by multivariate logistic regression analysis with a P < 0.05. According to the odds ratios (ORs) value, each HMP variable was assigned a weighted integer, and the sum of the integers indicated the total risk score for each kidney. The validation cohort was used to verify the accuracy and reliability of the scoring model. RESULTS: HMP duration (OR = 1.165, 95% confidence interval [CI]: 1.008-1.360, P = 0.043), resistance (OR = 2.190, 95% CI: 1.032-10.20, P < 0.001), and flow rate (OR = 0.931, 95% CI: 0.894-0.967, P = 0.011) were the independent predictors of identified DGF. The HMP predictive score ranged from 0 to 14, and there was a clear increase in the incidence of DGF, from the low predictive score group to the very high predictive score group. We formed four increasingly serious risk categories (scores 0-3, 4-7, 8-11, and 12-14) according to the frequency associated with the different risk scores of DGF. The HMP predictive score indicates good discriminative power with a c-statistic of 0.706 in the validation cohort, and it had significantly better prediction value for DGF compared to both terminal flow (P = 0.012) and resistance (P = 0.006). CONCLUSION: The HMP predictive score is a good noninvasive tool for assessing the quality of DCD kidneys, and it is potentially useful for physicians in making optimal decisions about the organs donated.

Beneficial Effect of Moderately Increasing Hypothermic Machine Perfusion Pressure on Donor after Cardiac Death Renal Transplantation.

BACKGROUND: Vascular resistance and flow rate during hypothermic machine perfusion (HMP) of kidneys is correlated with graft function. We aimed to determine the effects of increasing HMP pressure versus maintaining the initial pressure on kidney transplantation outcomes. METHODS: We retrospectively reviewed the data of 76 primary transplantation patients who received HMP-preserved kidneys from 48 donors after cardiac death between September 1, 2013, and August 31, 2015. HMP pressure was increased from 30 to 40 mmHg (1 mmHg = 0.133 kPa) in kidneys with poor flow and/or vascular resistance (increased pressure [IP] group; 36 patients); otherwise, the initial pressure was maintained (constant pressure group; 40 patients). Finally, the clinical characteristics and transplantation outcomes in both groups were assessed. RESULTS: Delayed graft function (DGF) incidence, 1-year allograft, patient survival, kidney function recovery time, and serum creatinine level on day 30 were similar in both groups, with improved flow and resistance in the IP group. Among patients with DGF, kidney function recovery time and DGF duration were ameliorated in the IP group. Multivariate logistic regression analysis revealed that donor hypertension (odds ratio [OR]: 1.43, 95% confidence interval [CI]: 1.02-2.06, P = 0.035), donor terminal serum creatinine (OR: 1.27, 95% CI: 1.06-1.62, P = 0.023), warm ischemic time (OR: 3.45, 95% CI: 1.97-6.37, P = 0.002), and terminal resistance (OR: 3.12, 95% CI: 1.76-6.09, P = 0.012) were independent predictors of DGF. Cox proportional hazards analysis showed that terminal resistance (hazard ratio: 2.06, 95% CI: 1.32-5.16, P = 0.032) significantly affected graft survival. CONCLUSION: Increased HMP pressure improves graft perfusion but does not affect DGF incidence or 1-year graft survival.

Arctigenin: A two-edged sword in ischemia/reperfusion induced acute kidney injury.

Arctigenin (ATG) is one of the main active substances in fruit derived from Arctium lappa L. Previous studies have reported that ATG have antitumor, neuroprotective, antioxidant, antifibrosis and anti-inflammatory functions. However, the actions of ATG in kidney with acute injury following ischemia/ reperfusion (I/R) is still uncertain. In our study, mice were subjected to kidney I/R by having the kidney pedicles clamped and administered with vehicle or ATG (1, 3 or 9 mg/kg/d) via oral gavage for 7 consecutive days prior to I/R. Notably, ATG aggravated kidney I/R injury with the concentration increases. Multiple biochemical assays and histological examination showed ATG significantly alleviated the inflammatory response as reflected by a decreased expression of proinflammatory cytokine, TLR4/MyD88, and NF-κB, along with the infiltration of CD68+ macrophage and CD11b+Gr1+ neutrophil in the kidneys. Meanwhile, ATG alleviated I/R-induced oxidative stress proved by increasing kidney manganese superoxide dismutase and glutathione peroxidase activity but reducing levels of malonaldehyde and inducible nitric oxide synthase. On the contrary, apoptosis was significantly increased in kidneys of ATG-treated mice compared with vehicle-treated controls, especially in tubular cells. There were increased numbers of TUNEL positive cells and increased Bcl-2, Bax, cleaved-caspase-3, and cleaved-caspase-9 expression. The current study demonstrates that pretreatment of ATG aggravates I/R induced acute kidney injury by increasing apoptosis of tubular cells despite reducing infiltrating inflammatory cells and proinflammatory cytokine.

Early Immunosuppressive Exposure of Enteric-Coated-Mycophenolate Sodium Plus Tacrolimus Associated with Acute Rejection in Expanded Criteria Donor Kidney Transplantation.

BACKGROUND: Immunosuppressive 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. METHODS: We 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)0-12h and Tac C0were measured at the 1st week and the 1st month posttransplant, respectively. The correlation was assessed by multivariate logistic regression. RESULTS: The occurrence rates of BPAR and antibody-mediated rejection were 24.1% and 10.3%, respectively. A low level of MPA-AUC0-12h at the 1st 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-AUC0-12hlevel was <30 mg·h-1·L-1 at the 1st week (15.0% vs. 44.4%) or the Tac C0was <4 ng/ml at the 1st month posttransplant (33.3% vs. 21.6%). Multivariable logistic regression analysis showed that the MPA-AUC0-12h at the 1st week (OR: 0.842, 95% CI: 0.784-0.903) and the Tac C0at the 1st month (OR: 0.904, 95% CI: 0.822-0.986) had significant inverse correlation with BPAR (P < 0.05). CONCLUSIONS: Low-level exposure of MPA and Tac C0in the early weeks posttransplant reflects an increased acute rejection risk, which suggested that MPA-AUC0-12h <30 mg·h-1·L-1 and Tac C0 <4 ng/ml should be avoided in the first few weeks after transplantation.

Knockdown of NLRC5 attenuates renal I/R injury in vitro through the activation of PI3K/Akt signaling pathway.

NLRC5, as the largest member of nucleotide-binding domain and leucine-rich repeat (NLR) family, was involved in various physiological processes, such as inflammation, fibrosis, innate immunity and diabetic nephropathy. However, the role of NLRC5 in acute kidney injury remains unclear. The aim of this study was to investigate the role of NLRC5 in human renal proximal tubular epithelial cells (HK-2) exposed to hypoxia/reoxygenation (H/R). Our results demonstrated that the expression of NLRC5 was significantly up-regulated in HK-2 cells exposed to H/R. Knockdown of NLRC5 significantly improved the viability of HK-2 cells exposed to H/R. In addition, knockdown of NLRC5 efficiently inhibited H/R-induced oxidative stress and apoptosis in HK-2 cells. Mechanistically, knockdown of NLRC5 markedly enhanced the activation of PIK3/Akt signaling pathway in H/R-stimulated HK-2 cells. In summary, our findings indicate that knockdown of NLRC5 attenuates renal I/R injury in vitro through the activation of PI3K/Akt signaling pathway.

Comparison of the characteristics of macrophages derived from murine spleen, peritoneal cavity, and bone marrow.

Macrophages have a diverse set of functions based upon their activation states. The activation states, including resting (M0) and polarizing (M1 and M2) states, of macrophages derived from the mouse bone marrow, spleen, and peritoneal cavity (BMs, SPMs, and PCMs, respectively) were compared. We evaluated the macrophage yield per mouse and compared the surface markers major histocompatibility complex (MHC) II and CD86 by flow cytometry. The relative mRNA levels of tumor necrosis factor-α (TNF-α), interleukin (IL)-1ß, mannose receptor (MR), and Ym1 in the M0, M1, and M2 states were also compared using real-time polymerase chain reaction (PCR) analysis. Bone marrow yielded the most macrophages with the best homogeneity, but they were polarized toward the M2 phenotype. All three types of macrophages had the capacity to polarize into the M1 and M2 states, but SPMs had a stronger capacity to polarize into M1. The three types of macrophages showed no differences in their capacity to polarize into the M2 state. Therefore, the three types of macrophages have distinct characteristics regardless of their resting or polarizing states. Although bone marrow can get large amounts of homogeneous macrophages, the macrophages cannot replace tissue-derived macrophages.

Predictive Score Model for Delayed Graft Function Based on Easily Available Variables before Kidney Donation after Cardiac Death.

BACKGROUND: How to evaluate the quality of donation after cardiac death (DCD) kidneys has become a critical problem in kidney transplantation in China. Hence, the aim of this study was to develop a simple donor risk score model to evaluate the quality of DCD kidneys before DCD. METHODS: A total of 543 qualified kidneys were randomized in a 2:1 manner to create the development and validation cohorts. The donor variables in the development cohort were considered as candidate univariate predictors of delayed graft function (DGF). Multivariate logistic regression was then used to identify independent predictors of DGF with P < 0.05. Date from validation cohort were used to validate the donor scoring model. RESULTS: Based on the odds ratios, eight identified variables were assigned a weighted integer; the sum of the integer was the total risk score for each kidney. The donor risk score, ranging from 0 to 28, demonstrated good discriminative power with a C-statistic of 0.790. Similar results were obtained from validation cohort with C-statistic of 0.783. Based on the obtained frequencies of DGF in relation to different risk scores, we formed four risk categories of increasing severity (scores 0-4, 5-9, 10-14, and 15-28). CONCLUSIONS: The scoring model might be a good noninvasive tool for assessing the quality of DCD kidneys before donation and potentially useful for physicians to make optimal decisions about donor organ offers.

Polyglycolic Acid Fibrous Scaffold Improving Endothelial Cell Coating and Vascularization of Islet.

BACKGROUND: Improving islet graft revascularization has become a crucial task for prolonging islet graft survival. Endothelial cells (ECs) are the basis of new microvessels in an isolated islet, and EC coating has been demonstrated to improve the vascularization and survival of an islet. However, the traditional method of EC coating of islets has low efficiency in vitro. This study was conducted to evaluate the effect of a polyglycolic acid (PGA) scaffold on the efficiency of islet coating by ECs and the angiogenesis in the coated islet graft. METHODS: A PGA fibrous scaffold was used for EC coating of islet culture and was evaluated for its efficiency of EC coating on islets and islet graft angiogenesis. RESULTS: In in vitro experiments, we found that apoptosis index of ECs-coating islet in PGA group (27% ± 8%) was significantly lower than that in control group (83% ± 20%, P < 0.05) after 7 days culture. Stimulation index was significantly greater in the PGA group than in the control group at day 7 after ECs-coating (2.07 ± 0.31 vs. 1.80 ± 0.23, P < 0.05). vascular endothelial growth factor (VEGF) level in the PGA group was significantly higher than the coating in the control group after 7 days culture (52.10 ± 13.50 ng/ml vs. 16.30 ± 8.10 ng/ml, P < 0.05). Because of a tight, circumvallated, adhesive and three-dimensional growth microenvironment, islet cultured in a PGA scaffold had higher coating efficiency showing stronger staining intensity of enzyme than those in the control group after 14 days of culture following ECs-coating. For in vivo study, PGA scaffold significantly prolonged the average survival time of EC-coated islet graft after transplantation compared with control group (15.30 ± 5.60 days vs. 8.30 ± 2.45 days, P < 0.05). The angiogenesis and area of survived grafts were more in the PGA group compared with the control group by measuring the mean microvessel density (8.60 ± 1.21/mm2 vs. 5.20 ± 0.87/mm2, P < 0.05). In addition, expression of VEGF and tyrosin-protein kinase receptor (Tie-2) gene increased in PGA scaffold group than that in control group by real-time reverse transcription-polymerase chain reaction analysis. CONCLUSIONS: These results demonstrate that the efficiency of EC coating of islets was successfully increased by culturing ECs on a PGA scaffold. This method enhances the function, survival, and vascularization of isolated islets in vitro and in vivo.

Treatment of cytomegalovirus infection after renal transplantation: experience from a single center in China.

BACKGROUND: We compared the efficacy and safety of 2 different treatments of CMV infection, including asymptomatic CMV replication and CMV disease. MATERIAL AND METHODS: 852 renal transplantation recipients, including asymptomatic CMV replication and CMV disease, received antiviral therapies of intravenous acyclovir or comprehensive anti-infection solution, mainly with intravenous ganciclovir. Effect, time, acute allograft rejection, and safety were analyzed during the antiviral therapy RESULTS: The total effective rates were higher with ganciclovir in both asymptomatic CMV replication (98.96% vs. 84.90%) and CMV disease (96.29% vs. 50.36%). Ganciclovir significantly shortened antiviral therapy duration in both asymptomatic CMV replication (15.0 ± 2.3 days vs. 16.0 ± 3.4 days) and CMV disease (19.7 ± 3.1 days vs. 21.5 ± 4.0 days). The acute allograft rejection incidences were significantly lower with ganciclovir in both asymptomatic CMV replication (8% vs. 14%) and CMV disease (11% vs. 22%). CMV-IEA was detected in renal grafts of patients with acute rejection. There was more CMV-associated acute rejection using acyclovir than using ganciclovir. Except for the higher incidence of anemia leucopenia and anemia with ganciclovir, the safety profiles of both drugs were similar. CONCLUSIONS: Comprehensive anti-infection solution, mainly with intravenous ganciclovir, can effectively treat CMV infection, shorten duration of therapy, and decrease acute rejection. The few adverse effects had negligible effects on use of ganciclovir.

Impact of HLA-G 14-bp polymorphism on acute rejection and cytomegalovirus infection in kidney transplant recipients from northwestern China.

Human leukocyte antigen (HLA)-G plays an important role in promoting transplant tolerance and helping human cytomegalovirus (CMV) to subvert host defenses. Strong evidence suggests that HLA-G 14-bp insertion/deletion polymorphism influences the stability of HLA-G mRNAs and levels of protein expression. We hypothesized that HLA-G 14-bp polymorphism of recipients has an influence on the risk of acute rejection (AR) and CMV infection. We investigated the impact of HLA-G 14-bp polymorphism on a total of 363 unrelated Chinese Han individuals who included 42 kidney transplant recipients with AR, 43 recipients with CMV infection, 102 recipients with stable allograft function (STA), and 176 healthy controls (HC). No statistically significant difference was found between all kidney transplant patients and HC (P=0.149). But, our data showed an increased frequency of homozygous genotype +14/+14 bp (P(c)=0.004) and allele +14 bp (P(c)=0.002) in patients with AR when compared with STA, with the odds ratio of 3.17 and 2.28, respectively. Moreover, we found that the frequency of the -14/-14 bp genotype (P(c)=0.008) and the -14 bp allele (P(c)=0.016) was increased in patients with CMV infection when compared with STA, with the OR of 2.66 and 1.96, respectively. Multivariate analysis further demonstrated that HLA-G homozygous +14 bp and -14 bp genotypes were an independent risk factor for allograft rejection and CMV infection, respectively. In conclusion, this study identified an important genetic risk factor for acute allograft rejection, and it was the first to show a significant correlation between HLA-G 14-bp polymorphism and CMV infection after kidney transplantation from northwestern China.

[The influence of rapamycin on BTLA expression of human peripheral blood T lymphocytes].

AIM: To explore the effect of rapamycin (RPM) on the expression of B and T lymphocyte attenuate (BTLA) on human peripheral blood T lymphocytes, providing a experimental basis for application of RPM to organ transplantation and autoimmune diseases. METHODS: Human peripheral blood mononuclear cells were isolated by Ficoll density gradient centrifugation, and then the T cells were isolated from PBMCs with immunomagnetic beads. Concanavalin A (Con A) used to stimulate and activate the human peripheral blood T cells. The proliferation of T cells was detected by MTT colorimetry. The levels of IL-2 and IFN-γ in cell culture supernatant were detected by ELISA. The expression of BTLA on T cells was assayed by Flow cytometry. RESULTS: The expression of BTLA on T cells treated with various concentrations (10-1 000 ng/L) of RPM had no significant difference, while had significant difference (P<0.01) by compared with RPM non-treatment group. ELISA detection manifested that compared with the untreated group different concentrations of RPM could significantly inhibit the IL-2 and IFN-γ secretion and significantly inhibited T lymphocyte proliferation (P<0.01). CONCLUSION: RPM has little effect on expression BTLA, but has stronger inhibition on lymphocyte proliferation and inflammatory cytokines secretion. Suggesting that RPM is suitable for the treated of organ transplant rejection and autoimmune diseases.

[Evaluation of immune status of kidney transplant recipients by combined HLA-G5 and sCD30].

OBJECTIVE: to study the relationship between the expression of serum human leucocyte antigen-G5 (HLA-G5)/soluble CD30 (sCD30) and the function of renal graft in kidney transplant recipients and investigate the immune status of recipients with combined HLA-G5 and sCD30. METHODS: from January 2002 to November 2008, a total of 66 kidney transplant recipients in our centre were selected as subjects and divided into three groups: stable function of renal graft (n = 38), acute rejection (n = 15) and chronic rejection (n = 13). The expressions of serum HLA-G5 and sCD30 were detected. There were two different immune conditions with acute/chronic allograft rejection and normal renal graft in kidney transplant recipients as evaluated by combined HLA-G5 and sCD30. The sensitivity, specificity and critical value of the method were analyzed by the curve of receiver operating characteristic. RESULTS: the levels of HLA-G5 and sCD30 were significantly correlated with serum creatinine (r = -0.493, 0.691, both P < 0.01). Within the first year post-transplantation, the sensitivity was 78.6% and the specificity 85.7% when HLA-G5 critical value 82 microg/L and sCD30 critical value 12.2 microg/L. After one year post-transplantation: the sensitivity was 92.3% and the specificity 84.6% when HLA-G5 critical value 141 microg/L and sCD30 critical value 10.3 microg/L. CONCLUSION: the immune state of recipients are evaluated by combine HLA-G5 and sCD30 which may be a simple and valid method.

[Preventive effect of poria cocos on acute rejection of renal transplantation in rats].

OBJECTIVE: To study the effect of Poria cocos (Pcs) in preventing acute rejection of rats after renal transplantation and its mechanism. METHODS: Rat orthotopic renal transplantation model was performed with Wistar rat as donor and SD rat as donee. All donees were divided into 4 groups, 10 in each group, before transplantation. They were treated respectively with normal saline 5 mL x kg(-1) x d(-1) (A), Pcs 25 mg x kg(-1) x d(-1) (B), Pcs 50 mg x kg(-1) x d(-1) (C) and ciclosporin A (CsA) 5 mg x kg(-1) x d(-1) (D) by intragastric administration. The renal allograft survival time (ST) was recorded, and the serum levels of creatinine (SCr), interleukin-2 (IL-2), gamma-interferon (gamma-IFN), CD4+, CD8+ lymphocytes percentage, CD4+/CD8+ ratio, as well as the pathologic changes were observed one week after transplantation. RESULTS: ST of the renal graft in Groups C and D was significantly longer with pathologic change evidently less than those in Groups A and B (P<0.01), and the ST in Group C was shorter that in Group D (P<0.05). Changes of renal function and urine volume were identified to the pathological change of graft, the initiating time of renal dysfunction was later in Groups C and D than that in Groups A and B. Serum levels of IL-2, IFN-gamma and CD4+ percentage in Group C were significantly lower than those in Groups A and B, but higher than those in Group D respectively (P<0.05 or P<0.01), while CD8+ percentage in Group C was significantly lower than that in Group A (P<0.05), but insignificantly different to that in Groups B and D (P>0.05). CONCLUSION: Pcs shows good dosage-dependent effect in suppressing acute rejection of renal transplantation, but the effect is inferior to that of CsA.