A bioengineered drug-Eluting scaffold accelerated cutaneous wound healing In diabetic mice.

Hyperglycemia in diabetic patients can greatly hinder the wound healing process. In this study we investigated if the engagement of F4/80(+) murine macrophages could accelerate the cutaneous wound healing in streptozotocin induced diabetic mice. To facilitate the engagement of macrophages, we engineered a drug-eluting electrospun scaffold with a payload of monocyte chemoattractant protein-1 (MCP-1). MCP-1 could be readily released from the scaffold within 3 days. The electrospun scaffold showed no cytotoxic effects on human keratinocytes in vitro. Full-thickness excisional cutaneous wound was created in diabetic mice. The wound fully recovered within 10 days in mice treated with the drug-eluting scaffold. In contrast, the wound took 14 days to fully recover in control groups. The use of drug-eluting scaffold also improved the re-epithelialization. Furthermore, we observed a larger population of F4/80(+) macrophages in the wound bed of mice treated with drug-eluting scaffolds on day 3. This marked increase of macrophages in the wound bed could have contributed to the accelerated wound healing. Our study shed new light on an immuno-engineering solution for wound healing management in diabetic patients.

Excessive intraoperative blood loss independently predicts recurrence of hepatocellular carcinoma after liver transplantation.

BACKGROUND: Several studies have investigated the effect of intraoperative blood loss (IBL) on recurrence of tumors. However, the independent effect of IBL on oncological outcome after liver transplantation (LT) for hepatocellular carcinoma (HCC) is unclear. METHODS: A total of 479 patients who underwent LT for HCC from January 2001 to December 2012 at our institution were enrolled in this retrospective study. Kaplan-Meier and Cox regression methods were used to assess the recurrence rate, as well as its risk factors. Stratified analysis was performed to further examine the effect of IBL on HCC recurrence according to different characteristics of tumors. We also investigated the independent risk factors for excessive IBL using logistic regression analysis. RESULTS: The median follow-up was 28 months (range, 1-131 months). Kaplan-Meier analysis with the log-rank test according to IBL at per liter intervals showed that IBL > 4 L was significantly associated with a higher recurrence rate (P < 0.001). Multivariate analysis identified that IBL > 4 L (P < 0.001; hazard ratio [HR] = 2.32, 95 % confidence interval [CI] = 1.60-3.36) was an independent risk factor for post-LT HCC recurrence, as well as age < 60 years, exceeding Milan criteria, α-fetoprotein levels > 400 ng/mL, and micro- and macrovascular invasion. IBL > 4 L (P < 0.001; HR = 2.45, 95 % CI = 1.64-3.66) was also independently associated with early (within 1 year) recurrence after LT. Furthermore, a significant correlation between IBL > 4 L and vascular invasion (P = 0.019) was found. IBL > 4 L was independently associated with HCC recurrence for patients with vascular invasion, but not for patients without vascular invasion. Finally, we found that the presence of ascites, model for end-stage liver disease score, and operation time were independent risk factors for IBL > 4 L. CONCLUSIONS: Excessive IBL is an independent predictor of HCC recurrence after LT, especially in patients with vascular invasion.

Validation of a criteria-specific long-term survival prediction model for hepatocellular carcinoma patients after liver transplantation.

The aim of this study was to validate a criteria-specific long-term survival prediction model (MHCAT) in a large cohort of hepatocellular carcinoma (HCC) patients after liver transplantation (LT) in China. Independent risk factors in MHCAT were retrospectively analysed for HCC patients recorded in the China Liver Transplant Registry. Survival predictions for each patient were calculated using MHCAT scores and the Metroticket formula separately, and the prediction efficacy of MHCAT and Metroticket was compared using the area under ROC curve (c-statistic). A total of 1371 LTs for HCC were analysed in the study, with a median follow-up of 22.2 months (IQR 6.1-72.4 months). The proportions meeting the Milan, UCSF, Fudan and Hangzhou criteria were 34.4%, 39.7%, 44.2% and 51.9%, respectively. The c-statistics for MHCAT predictions of 3- and 5-year survival rates of HCC recipients were 0.712-0.727 and 0.726-0.741, respectively. Among these patients, 1298 LTs for HCC were ultimately selected for the comparison analysis for prediction efficacy. The c-statistic of MHCAT for predictions of 3-year survival with reference to the Milan, UCSF and Fudan criteria was significantly increased compared with that for Metroticket (p < 0.05). In conclusion, MHCAT can effectively predict long-term survival for HCC recipients after LT.

The therapeutic effect of monocyte chemoattractant protein-1 delivered by an electrospun scaffold for hyperglycemia and nephrotic disorders.

Here, we investigated in diabetic mice the therapeutic effect of monocyte chemoattractant protein-1 (MCP-1), locally delivered by an electrospun scaffold, on transplanted islets. This therapeutic scheme is expected to exert a synergistic effect to ameliorate hyperglycemia and its associated nephrotic disorders. The cumulative amount of MCP-1 released from the scaffold in vitro within a 3-week window was 267.77 ± 32.18 ng, without a compromise in bioactivity. After 8 weeks following the transplantation, the islet population stimulated by MCP-1 was 35.14%± 7.23% larger than the non-stimulated islet population. Moreover, MCP-1 increased concentrations of blood insulin and C-peptide 2 by 49.83%± 5.29% and 43.49%± 9.21%, respectively. Consequently, the blood glucose concentration in the MCP-1 group was significantly lower than that in the control group at week 2 post-surgery. MCP-1 also enhanced the tolerance of sudden oral glucose challenge. The rapid decrease of blood creatinine, urine creatinine, and blood urea nitrogen suggested that the recovery of renal functions compromised by hyperglycemia could also be attributed to MCP-1. Our study shed new light on a synergistic strategy to alleviate hyperglycemia and nephrotic disorders in diabetic patients.

Suppression of allograft rejection by Tim-1-Fc through cross-linking with a novel Tim-1 binding partner on T cells.

Engagement of T-cell immunoglobulin mucin (Tim)-1 on T cells with its ligand, Tim-4, on antigen presenting cells delivers positive costimulatory signals to T cells. However, the molecular mechanisms for Tim-1-mediated regulation of T-cell activation and differentiation are relatively poorly understood. Here we investigated the role of Tim-1 in T-cell responses and allograft rejection using recombinant human Tim-1 extracellular domain and IgG1-Fc fusion proteins (Tim-1-Fc). In vitro assays confirmed that Tim-1-Fc selectively binds to CD4(+) effector T cells, but not dendritic cells or natural regulatory T cells (nTregs). Tim-1-Fc was able to inhibit the responses of purified CD4(+) T cells that do not express Tim-4 to stimulation by anti-CD3/CD28 mAbs, and this inhibition was associated with reduced AKT and ERK1/2 phosphorylation, but it had no influence on nTregs. Moreover, Tim-1-Fc inhibited the proliferation of CD4(+) T cells stimulated by allogeneic dendritic cells. Treatment of recipient mice with Tim-1-Fc significantly prolonged cardiac allograft survival in a fully MHC-mismatched strain combination, which was associated with impaired Th1 response and preserved Th2 and nTregs function. Importantly, the frequency of Foxp3(+) cells in splenic CD4(+) T cells was increased, thus shifting the balance toward regulators, even though Tim-1-Fc did not induce Foxp3 expression in CD4(+)CD25(-) T cells directly. These results indicate that Tim-1-Fc can inhibit T-cell responses through an unknown Tim-1 binding partner on T cells, and it is a promising immunosuppressive agent for preventing allograft rejection.

Complement C3 deficiency prevent against the onset of streptozotocin-induced autoimmune diabetes involving expansion of regulatory T cells.

Recent studies have demonstrated that complement contributes to the development of autoimmune diabetes. However, the mechanisms remain unknown. Herein, using a model of streptozotocin (STZ)-induced diabetes, we found the presence of immune tolerance to self islet in complement C3-deficient mice after STZ. Higher number of CD4+CD25+ regulatory T cells (Tregs) with characteristics of expressing Foxp3 was observed in C3-/- mice. These C3-/- Tregs exhibited enhanced suppressive capacity to effector cell proliferation. The central role of Tregs was further evidenced by that depleting these cells using anti-CD25 antibody dramatically abrogated the preventive effects of C3 deficiency on STZ-induced diabetes. Importantly, transforming growth factor-ß (TGF-ß) was a key factor for Treg-mediated immune suppression as blocking TGF-ß activity reversed suppressive capacity of Tregs in vitro and diabetes-resistant effects of C3 deficiency in vivo. These findings suggest that resistance to overt diabetes in STZ-treated C3-/- mice involves a population of Tregs in TGF-ß-dependent manner.

Adjuvant treatment suppresses IL-17 production by T cell-independent myeloid sources in nonobese diabetic mice.

Recent studies have shown that Th17 cells, as a distinct lineage from Th1 and Th2 subsets, play an obligatory role in the pathogenesis of autoimmune diseases. It is well known that immunotherapy with Complete Freund's adjuvant (CFA) is effective in preventing from the onset of autoimmune diabetes in nonobese diabetic (NOD) mice. In the present study, we investigated whether CFA treatment restrained Th17 development and down-regulated Th17-related cytokine production in NOD mice. Th17-related cytokines (i.e. IL-17A, IL-17F, IL-21, IL-22, IL-23, IL-6, TGF-beta) production in splenocytes was decreased dramatically on day 18 following CFA immunization. This effect was also observed at 10 and 20 week after adjuvant treatment. Injection of IL-17 into CFA-treated diabetes-free mice led to occurrence of overt diabetes, indicating that therapeutic effects of adjuvant treatment may be partially due to suppressing Th17 commitment. Interestingly, the main producer of IL-17 resided in a population of myeloid cells, which negatively expressed makers of neutrophil or macrophages. IL-23 stimulation did not alter the distribution of IL-17 in myeloid cells. Furthermore, this pattern of IL-17 expression was also present in Balb/c and C57BL/6 strains. These findings may have important implications for understanding of mechanisms underlying adjuvant treatment on autoimmune diseases.

Prediction of survival after liver transplantation for chronic severe hepatitis B based on preoperative prognostic scores: a single center's experience in China.

BACKGROUND: The aim of this study was to estimate the utility of a preoperative model of end-stage liver disease (MELD) score and Child-Turcotte-Pugh (CTP) score in predicting the prognosis after othotopic liver transplantation (OLT) for chronic severe hepatitis B (CSHB) and explore the prognostic factors. METHODS: The outcome of 137 patients who underwent OLT using donors after cardiac death (DCDs) for CSHB in our center was reviewed retrospectively. Survival analysis was performed using the Kaplan-Meier method; the log-rank test was used for univariate analysis; and the Cox proportional hazards regression model was used for prognostic factors screening. RESULTS: The overall mortality rate was 33.6% (46/137); and 1-month, 6-month, 1-year, and 5-year patient survival rates were 75.8, 72.0, 71.0, and 60.1%, respectively. Most patients (33/46) died during the first month after OLT. The area under the curve values generated by the receiver operating characteristics curves were 0.82 [95% confidence interval (CI) 0.72-0.92] and 0.68 (95% CI 0.58-0.79), respectively (P < 0.01), for the MELD and CTP models in predicting 1-month mortality after OLT. Patients with a preoperative MELD score <33.8 or a CTP score <12.5 had significantly better prognosis than those with higher scores (P < 0.05). Other mortality predictors include hepatic encephalopathy, preoperative infection, serum creatinine > or = 1.5 mg/dl. CONCLUSIONS: The MELD score was more efficient than the CTP score for evaluating the short-term prognosis in patients with CSHB undergoing OLT using DCDs, which should be taken into consideration during graft allocation.

Dendritic cells transduced with SOCS1 gene exhibit regulatory DC properties and prolong allograft survival.

SOCS1 is a key regulator of cytokine signaling and is important for maintaining balance in the immune system. It is thought to participate in negative feedback loops in cytokine signaling and may be an important signal for the regulation of dendritic cell (DC) maturation. However, it remains unclear whether DCs transduced with SOCS1 exhibit characteristics of regulatory DCs and induce allogeneic T-cell hyporesponsiveness. In this study, we constructed adenoviral vector coding SOCS1 (Ad-SOCS1) that can efficiently increase SOCS1 gene expression in bone marrow-derived dendritic cells. DCs transduced with Ad-SOCS1 (DC-SOCS1) expressed low levels of costimulatory and MHC molecules, were resistant to maturation and activation stimulation, induced allogeneic T-cell hyporesponsiveness, and promoted the generation of regulatory-like T cells in vitro. DC-SOCS1 pretreatment significantly prolonged the survival of allografts and led to a substantial increase in the generation of regulatory T cells. Our data suggest that SOCS1 inhibits DC maturation and induces regulatory DC generation, therefore possessing therapeutic potential to prevent rejection in organ transplantation.

Report of 8 cases of liver retransplantation.

BACKGROUND: Retransplantation of the liver is required for several complications of primary grafting, such as primary allograft non-function, hepatic artery thrombosis, biliary problems, or chronic ductopenic rejection. Surgeons usually take regrafting as the only pathway to treat those patients who are considered to have a poor outcome after the first operation. Whether the retransplantation is early or late, further attempts at rescue with a second or more grafts are associated with higher mortality and morbidity. However, retransplantation plays a role in improving survival of the patients. Therefore, it is necessary to summarize the experiences in liver retransplantation, as well as the factors influencing operative effects. METHOD: The clinical data of 8 patients who received liver retransplantation in our center were analyzed retrospectively. RESULTS: Complications of the biliary tract occurred in 5 of the 8 patients, chronic rejection in 2, and embolism in the hepatic artery in 1. Infections occurred in 7 patients before engraftment. Patient 1 had developed renal failure before the surgery, and he died of severe infection and multi-organ failure after transplantation. Patient 4 had a massive hemorrhage during the operation and also died of multi-organ failure after transplantation. Patient 7 developed intracranial hemorrhage and abdominal infection and died soon after transplantation. The other 5 patients recovered and discharged from the hospital. CONCLUSIONS: Liver retransplantation is the only measure that can be taken to save the lives of patients whose liver allograft fails to function. It is very important that the indications and time of retransplantation are carefully selected. Factors leading to harmful effects on retransplantation include the preoperative condition of the recipient, a difficult and prolonged operation, massive hemorrhage during the operation, and severe complications after the surgery.