Polydatin ameliorates hepatic ischemia-reperfusion injury by modulating macrophage polarization.

BACKGROUND: Polydatin, a glucoside of resveratrol, has been shown to have protective effects against various diseases. However, little is known about its effect on hepatic ischemia-reperfusion (I/R) injury. This study aimed to elucidate whether polydatin protects liver against I/R-induced injury and to explore the underlying mechanism. METHODS: After gavage feeding polydatin once daily for a week, mice underwent a partial hepatic I/R procedure. Serum alanine aminotransferase (ALT)/aspartate aminotransferase (AST), hematoxylin-eosin (H&E) and TdT-mediated dUTP nick-end labeling (TUNEL) staining were used to evaluate liver injury. The severity related to the inflammatory response and reactive oxygen species (ROS) production was also investigated. Furthermore, immunofluorescence and Western blotting were used to detect macrophage polarization and the NF-κB signaling pathway in macrophages. RESULTS: Compared with the I/R group, polydatin pretreatment significantly attenuated I/R-induced liver damage and apoptosis. The oxidative stress marker (dihydroethidium fluorescence, malondialdehyde, superoxide dismutase and glutathione peroxidase) and I/R related inflammatory cytokines (interleukin-1ß, interleukin-10 and tumor necrosis factor-α) were significantly suppressed after polydatin treatment. In addition, the result of immunofluorescence indicated that polydatin reduced the polarization of macrophages toward M1 macrophages both in vivo and in vitro. Western blotting showed that polydatin inhibited the pro-inflammatory function of RAW264.7 via down-regulating the NF-κB signaling pathway. CONCLUSIONS: Polydatin protects the liver from I/R injury by remodeling macrophage polarization via NF-κB signaling.

Aged-related Function Disorder of Liver is Reversed after Exposing to Young Milieu via Conversion of Hepatocyte Ploidy.

Previous study showed that senescent hepatocytes from aged liver could be rejuvenated after repopulated in the young recipient liver. The proliferative capacity of hepatocytes was restored with the senescence reversal. However, it is unknown whether metabolic and homeostatic function of aged liver, as well as age-dependent liver steatosis could be rejuvenated or alleviated. Here, we found that senescent hepatocytes from aged liver were rejuvenated after exposing to young blood. An autonomous proliferation of senescent hepatocytes which resulting in ploidy reversal might be the underlying mechanism of senescent reversal. After performing 2/3 partial hepatectomy (2/3PHx) in young blood exposed old liver, delayed DNA synthesis of senescent hepatocytes was rescued and the number of BrdU positive hepatocytes was restored from 4.39±2.30% to 17.85±3.21%, similarly to that in the young mice at 36 hours post 2/3PHx. Moreover, Cyclin A2 and Cyclin E1 overexpression of hepatocytes in aged liver facilitating the G1/S phase transition was contributed to enhance liver regeneration. Furthermore, lipid droplet spread widely in the elderly human liver and old mouse liver, but this aged-associated liver steatosis was alleviated as senescence reversal. Collectively, our study provides new thoughts for effectively preventing age-related liver diseases.

Inhibition of SIRT1 Limits Self-Renewal and Oncogenesis by Inducing Senescence of Liver Cancer Stem Cells.

PURPOSE: Cancer stem cells (CSCs) have been considered involving in tumorigenesis, local recurrence, and therapeutic drug resistance of hepatocellular carcinoma (HCC). To investigate novel and effective methods for targeting hepatic CSCs is crucial for a permanent cure of liver cancer. METHODS: The expression level of SIRT1 was detected in CSCs of HCC tissues and cancer cell lines. Expression of CSC markers, the self-renewal and tumorigenic ability of liver CSCs were analyzed with SIRT1 inhibition. Cellular senescence-related markers were used to detect CSCs senescence after inhibition of SIRT1. RESULTS: SIRT1 was highly expressed in CSCs of HCC cell lines and human HCC tissues. In vitro study revealed that decreasing of SIRT1 level significantly downregulated the stemness-associated genes of liver CSCs and reduced the CSC stemness properties. Also, downregulated SIRT1 suppressed liver CSCs proliferation by decreasing their self-renewal abilities. Furthermore, CSCs with decreased SIRT1 expression showed limited tumorigenicity and formed smaller HCC tumor in vivo. And SIRT1 decreased CSCs became more susceptible to chemotherapeutic drugs. Mechanistically, SIRT1 decreased CSCs became senescence through the activation of p53-p21 and p16 pathway. The data further indicated that the tumor formed from SIRT1-knockdown CSCs exhibited higher senescence-associated ß-galactosidase (SA-ß-Gal) activity but lower proliferative capacity. CONCLUSION: Taken together, these findings pointed that induction of senescence in liver CSCs is an effective tumor suppression method for HCC, and SIRT1 may be served as a promising target for HCC treatment.

Bruton's Tyrosine Kinase Inhibitor Attenuates Warm Hepatic Ischemia/Reperfusion Injury via Modulation of the NLR Family Pyrin Domain Containing 3 Inflammasome.

The NLR family pyrin domain containing 3 (NLRP3) inflammasome is a widely studied inflammasome that plays a critical role in inflammatory responses. Many triggers, including microbial pathogens (ie, bacteria and viruses) and other signals (ie, reactive oxygen species, adenosine triphosphate, urate, silicon, and asbestos), can stimulate the NLRP3 inflammasome. Liver ischemia/reperfusion (I/R) injury is a common pathologic process during liver surgery and shock and can induce severe liver damage. Although its pathogenesis is still unclear, oxidative stress and overproduction of the inflammatory response are likely to contribute to I/R injury. The NLRP3 inflammasome is activated during the I/R process, resulting in further recruitment and activation of caspase-1. Activated caspase-1 cleaves the pro-forms of interleukin-1ß and interleukin-18 and results in their maturation, triggering a proinflammatory cytokine cascade and causing liver damage. Bruton's tyrosine kinase is a critical molecule involved in diverse cellular pathways, such as proliferation, apoptosis, inflammation, and angiogenesis. Intrahepatic Bruton's tyrosine kinase is mainly expressed on Kupffer cells and sinusoidal endothelial cells, and the inflammasome is activated in Kupffer cells. Our study found that inhibition of Bruton's tyrosine kinase effectively attenuated liver I/R injury by suppressing activation of the NLRP3 inflammasome in Kupffer cells.

Tailored classification of portal vein thrombosis for liver transplantation: Focus on strategies for portal vein inflow reconstruction.

Portal vein thrombosis (PVT) is currently not considered a contraindication for liver transplantation (LT), but diffuse or complicated PVT remains a major surgical challenge. Here, we review the prevalence, natural course and current grading systems of PVT and propose a tailored classification of PVT in the setting of LT. PVT in liver transplant recipients is classified into three types, corresponding to three portal reconstruction strategies: Anatomical, physiological and non-physiological. Type I PVT can be removed via low dissection of the portal vein (PV) or thrombectomy; porto-portal anastomosis is then performed with or without an interposed vascular graft. Physiological reconstruction used for type II PVT includes vascular interposition between mesenteric veins and PV, collateral-PV and splenic vein-PV anastomosis. Non-physiological reconstruction used for type III PVT includes cavoportal hemitransposition, renoportal anastomosis, portal vein arterialization and multivisceral transplantation. All portal reconstruction techniques were reviewed. This tailored classification system stratifies PVT patients by surgical complexity, risk of postoperative complications and long-term survival. We advocate using the tailored classification for PVT grading before LT, which will urge transplant surgeons to make a better preoperative planning and pay more attention to all potential strategies for portal reconstruction. Further verification in a large-sample cohort study is needed.

MiR-942-3p Promotes the Proliferation and Invasion of Hepatocellular Carcinoma Cells by Targeting MBL2.

MicroRNAs (miRNAs), a subgroup of small noncoding RNAs, play critical roles in tumor growth and metastasis. Accumulating evidence shows that the dysregulation of miRNAs is associated with the progression of hepatocellular carcinoma (HCC). However, the molecular mechanism by which miR-942-3p contributes to HCC remains undocumented. The association between miR-942-3p expression and the clinicopathological characteristics in HCC patients was analyzed by The Cancer Genome Atlas data set. The targets of miR-942-3p were identified by bioinformatic analysis and dual luciferase report assay. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and Transwell assays were performed to assess the functional role of miR-942-3p in HCC cells. Consequently, we found that miR-942-3p expression level was elevated in HCC tissues and cell lines as compared with the normal tissues and was associated with the pathological stage and tumor node metastasis (TNM) stage, acting as an independent prognostic factor of poor survival in patients with HCC. Ectopic expression of miR-942-3p enhanced the proliferation and invasive potential of HCC cells, but inhibition of miR-942-3p expression had the opposite effects. Mannose-binding lectin 2 (MBL2) was further identified as a direct target of miR-942-3p and possessed a negative correlation with miR-942-3p expression and unfavorable survival in patients with HCC. Restoration of MBL2 inhibited the progression of HCC cells and attenuated the tumor-promoting effects induced by miR-942-3p. In conclusion, miR-942-3p may act as an oncogenic factor in HCC cells by targeting MBL2 and provide a potential marker for patients with HCC.

Effect of Huaier granule on recurrence after curative resection of HCC: a multicentre, randomised clinical trial.

OBJECTIVE: There is little evidence that adjuvant therapy after radical surgical resection of hepatocellular carcinoma (HCC) improves recurrence-free survival (RFS) or overall survival (OS). We conducted a multicentre, randomised, controlled, phase IV trial evaluating the benefit of an aqueous extract of Trametes robinophila Murr (Huaier granule) to address this unmet need. DESIGN AND RESULTS: A total of 1044 patients were randomised in 2:1 ratio to receive either Huaier or no further treatment (controls) for a maximum of 96 weeks. The primary endpoint was RFS. Secondary endpoints included OS and tumour extrahepatic recurrence rate (ERR). The Huaier (n=686) and control groups (n=316) had a mean RFS of 75.5 weeks and 68.5 weeks, respectively (HR 0.67; 95% CI 0.55 to 0.81). The difference in the RFS rate between Huaier and control groups was 62.39% and 49.05% (95% CI 6.74 to 19.94; p=0.0001); this led to an OS rate in the Huaier and control groups of 95.19% and 91.46%, respectively (95% CI 0.26 to 7.21; p=0.0207). The tumour ERR between Huaier and control groups was 8.60% and 13.61% (95% CI -12.59 to -2.50; p=0.0018), respectively. CONCLUSIONS: This is the first nationwide multicentre study, involving 39 centres and 1044 patients, to prove the effectiveness of Huaier granule as adjuvant therapy for HCC after curative liver resection. It demonstrated a significant prolongation of RFS and reduced extrahepatic recurrence in Huaier group. TRIAL REGISTRATION: NCT01770431; Post-results.

Long-term exposure to PM2.5 lowers influenza virus resistance via down-regulating pulmonary macrophage Kdm6a and mediates histones modification in IL-6 and IFN-ß promoter regions.

Atmospheric particulates, especially PM2.5, not only damage the respiratory system, but also play important roles in pulmonary immunity. China is influenced by atmospheric diffusion conditions, industrial manufacturers, and heating and discharging. PM2.5 levels in the air rise substantially in the winter, which is also a period of flu high-incidence. Although an epidemiological link exists between PM2.5 and flu, we do not understand how long-term PM2.5 inhalation affects pulmonary immunity and the influenza virus response. Our study has prepared an in vivo PM2.5 mouse pharyngeal wall drop-in model and has found that PM2.5 exposure leads to mouse inflammatory injuries and furthers influenza A infection. Our results suggest that short-term exposure to PM2.5 significantly enhances the survival rate of influenza A-contaminated mice, while long-term PM2.5 inhalation lowers the capacity of pulmonary macrophages to secrete IL-6 and IFN-ß. A disorder in the pulmonary innate defense system results in increased death rates following influenza infection. On a macromolecular level, this mechamism involves Kdm6a down-regulation after long-term exposure to PM 2.5 and a resultant increase in H3K4 and H3K9 methylation in IL-6 and IFN-ß promoter regions. In summary, PM2.5 causes injuries of lung tissue cells and downregulates immune defense mechanisms in the lung.

A non-invasive magnetic resonance imaging-based model predicts portal venous pressure.

OBJECTIVE: To establish a non-invasive model for the assessment of portal venous pressure (PVP) based on the magnetic resonance (MR) parameters. METHODS: In this prospective study, contrast-enhanced magnetic resonance imaging (MRI) scan was performed in 109 patients indicated for upper abdominal surgeries after their written consents were obtained, and intraoperative PVP measurements were completed in 92 patients. Altogether 17 patients were excluded for not undergoing surgery or unsuccessful catheterization. A linear model was constructed for estimating PVP levels in 56 patients and further validation was conducted in the other 36 patients. RESULTS: The PVP levels were significantly correlated with MR parameters, including splenic volume (SV), splenic venous diameter (SVD), liver/splenic volume ratio, portal venous diameter, hepatic diameter, portal venous cross-sectional area, ascites, varices and arterial portal shunts. A linear model was established as follows: PVP (mmHg) = 2.529 + 1.572 × SVD (mm) + 0.231 × SV/body mass index (× 10(4) cm(5) /kg) + 3.44 × aspartate aminotransferase-to-platelet ratio index. This model showed excellent accuracy in the detection of portal hypertension, with the area under the receiver operating characteristic curve (AUROC) of 0.945 (95% CI 0.867-1.000), with the sensitivity and specificity of 91.7% and 93.7%, respectively. The agreement analysis revealed that the predictive value using this formula closely reflected the patients' actual PVP level. Moreover, the validation confirmed the accuracy of this model for the assessment of portal hypertension [AUROC 0.935 (95% CI 0.856-1.000)]. CONCLUSIONS: The MRI-based formula has great potential for detecting portal hypertension. As a non-invasive measurement, it may be clinically accepted for the replacement of invasive modalities after further refinement.

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.

Criteria-specific long-term survival prediction model for hepatocellular carcinoma patients after liver transplantation.

AIM: To establish a model to predict long-term survival of hepatocellular carcinoma (HCC) patients after liver transplantation (MHCAT). METHODS: Two hundred and twenty-three patients with HCC were followed for at least six years to identify independent risk factors for long-term survival after liver transplantation (LT). The criteria for HCC liver transplantation included the Milan, University of California San Francisco, Hangzhou and Shanghai Fudan criteria. The Cox regression model was used to build MHCAT specifying these criteria. A survival analysis was carried out for patients with high or low risk. RESULTS: The one-, three- and five-year cumulative survival of HCC patients after LT was 78.9%, 53.2% and 46.4%, respectively. Of the HCC patients, the proportion meeting the Hangzhou and Fudan criteria was significantly higher than the proportion meeting the Milan criteria (64.6% vs 39.5%, 52.0% vs 39.5%, P < 0.05). Moreover, the proportion meeting the Hangzhou criteria was also significantly higher than the proportion meeting other criteria (P < 0.01). Pre-operative alfa-fetoprotein level, intraoperative blood loss and retransplantation were common significant predictors of long-term survival in HCC patients with reference to the Milan, University of California San Francisco and Fudan criteria, whereas in MHCAT based on the Hangzhou criteria, total bilirubin, intraoperative blood loss and retransplantation were independent predictors. The c-statistic for MHCAT was 0.773-0.824, with no statistical difference among these four criteria. According to the MHCAT scoring system, patients with low risk showed a higher five-year survival than those with high risk (P < 0.001). CONCLUSION: MHCAT can effectively predict long-term survival for HCC patients, but needs to be verified by multi-center retrospective or randomized controlled trials.

A quantitative assessment model of T-cell immune function for predicting risks of infection and rejection during the early stage after liver transplantation.

Although more and more clinical studies indicated that ImmuKnow assay could efficiently assess the immune status of recipients, it still has the challenge to predict the occurrence of clinical adverse events. This study aimed to establish a quantitative assessment model, which could more efficiently predict immune function of T lymphocytes after liver transplantation based on three indexes: CD4+ T lymphocyte count (C), CD4+/CD8+ ratio (R), and ImmuKnow adenosine triphosphate (ATP) value (A). We selected 194 recipients and measured the A, C, and R index every week, then obtained the Fisher linear discriminant functions by SPSS 16.0. Next, we divided the recipients into three groups: infection, stable, and rejection groups according to clinical status. After calculating, the discriminant function, 0.012A + 0.019C + 1.322R (simplified into T = 2A + 3C + 200R), was selected to represent the T-cell-mediated immune function. Based on the model, the optimal cutoff T values for infection and rejection were 1415 (sensitivity = 80%, specificity = 79.9%,AUC = 92.3%) and 1939.5 (sensitivity = 93.9%, specificity = 77.6%, AUC = 88.6%), relatively (p < 0.001). In conclusion, this model may be a more feasible way to evaluate the cellular immune function status in liver transplantation recipients.

Postreperfusion syndrome during orthotopic liver transplantation: a single-center experience.

BACKGROUND: Marked hemodynamic alteration, commonly referred to as postreperfusion syndrome (PRS), often occurs after revascularization of the donor organ during orthotopic liver transplantation (OLT) and is associated with poor outcomes. This study aimed to investigate the incidence, predictive factors and clinical outcomes of PRS in Chinese patients following OLT at a liver transplantation center in China. METHODS: Over a 5-year period, 330 consecutive patients who had undergone OLT for hepatocellular carcinoma or cirrhosis were included in this retrospective study. PRS was defined as a >30% decrease in the mean arterial pressure compared with that before revascularization for more than 1 minute during the first 5 minutes of graft reperfusion. The patients were divided into 2 groups according to the development of PRS: group 1 (patients with PRS, n=56) and group 2 (patients without PRS, n=274). The demographic characteristics, operative and postoperative courses, and outcomes of the patients were analyzed using SPSS version 18.0. RESULTS: Multivariate regression analysis showed that left ventricular diastolic dysfunction determined by echocardiography and prolonged cold ischemia time were the independent risk factors for PRS. More patients in group 1 showed postoperative renal dysfunction than those in group 2 (19.23% vs 8.4%). Moreover, patients in group 1 also had higher intraoperative (7.14% vs 0%) and postoperative mortalities (26.92% vs 12.04%). CONCLUSION: Left ventricular diastolic dysfunction and prolonged cold ischemia time contribute to a high incidence of PRS, which is associated with adverse outcomes in Chinese patients following OLT.

A potential role for the homeoprotein Hhex in hepatocellular carcinoma progression.

Hepatocellular carcinoma (HCC), the most common primary malignant tumor of the liver, often associated with the dysregulation of transcriptional pathways involved in cell growth and differentiation. The hematopoietically expressed homeobox protein (Hhex) is an important transcription factor throughout liver development and is essential to liver bud formation and hepatoblast differentiation. Here, we report a relationship between Hhex expression and HCC. First, adenovirus-mediated Hhex delivery into the hepatoma cell line, Hepa1-6, resulted in decreased expression of several proto-oncogenes (c-Jun and Bcl2), increased expression of some tumor suppressor genes (P53 and Rb), and enhanced expression of a cluster of hepatocytic and bile ductular markers. Second, Hhex expression significantly attenuated Hepa1-6 tumorigenicity in nude mice. Third, we report a correlation between Hhex expression and the differentiation state of human HCC. In 24 cases of clinical specimens, there was a significant difference in Hhex expression between poorly differentiated HCC and well-differentiated HCC (P < 0.001). Taken together, these results indicate that Hhex is a potential candidate molecular marker for HCC pathological evaluation, suggesting a need to evaluate Hhex as a potential target for therapeutic intervention.

Reconstruction of the middle hepatic vein tributary in adult right lobe living donor liver transplantation.

BACKGROUND: In adult-to-adult living donor liver transplantation (LDLT), the use of a right lobe graft without the middle hepatic vein (MHV) can cause hepatic congestion and disturbance of venous drainage. To solve this problem, we successfully used cadaveric venous allografts preserved in 4 °C University of Wisconsin (UW) solution within 10 days as interposition veins for drainage of the paramedian portion of the right lobe in adult LDLT. METHODS: From June 2007 to January 2008, 11 adult LDLT patients received modified right liver grafts. The major MHV tributaries (greater than 5 mm in diameter) of 9 cases were preserved and reconstructed using cadaveric interposition vein allografts that had been stored for 1 to 10 days in 4 °C UW solution. The regeneration of the paramedian sector of the grafts and the patency of the interposition vein allografts were examined by Doppler ultrasonography after the operation. RESULTS: MHV tributaries were reconstructed in 9 recipients. Only 1 recipient died of renal failure and severe pulmonary infection on day 9 after transplantation without any hemiliver venous outflow obstruction. The other 8 recipients achieved long-term survival with a median follow-up of 30 months. The cumulative patency rates of the 8 recipients were 63.63% (7/11), 45.45% (5/11), 45.45% (5/11) and 36.36% (4/11) at 3, 6, 12 and 24 months, respectively. Regeneration of the paramedian sectors was equivalent. CONCLUSION: The cadaveric venous allograft preserved in 4 °C UW solution within 10 days serves as a useful alternative for interposition veins in facilitating implantation of a right lobe graft and guarantees outflow of the MHV.

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.

The relationship between adenosine triphosphate within CD4(+) T lymphocytes and acute rejection after liver transplantation.

BACKGROUND: There have been increasing interests in the relationship between CD4(+) T lymphocytes and acute rejection (AR) in transplantation. In this study, we explore the role of CD4(+) T lymphocytes after liver transplantation. METHODS: From February to October 2009, 87 patients underwent liver transplantation. They were divided into the AR group and non-acute rejection (NAR) group, with 56 healthy individuals in the control group. Blood specimens were collected preoperatively and at one, two, and four wk postoperatively for all groups and also on the day when AR occurred and one wk after intravenous glucocorticoid therapy for the AR group. Adenosine triphosphate (ATP) levels were measured using the ImmuKnow™ test kits for immune cell functions. RESULTS: After transplantation, the ATP levels within CD4(+) T lymphocytes were significantly elevated in the two groups when compared with the preoperative levels. It peaked in the AR group and was significantly higher than that of the NAR group (p < 0.05). By ROC curve analysis, the obvious elevation of the ATP value one wk after transplantation had better sensitivity and specificity in diagnosing the AR. The ATP sensitivity rate for early AR was 85.7% and specificity rate 80.9% when the cutoff value was 407 µg/L. The ATP value collected on the day of AR occurrence has apparently positive correlation with the rejection acting index (RAI) (p < 0.01). After the intravenous glucocorticoid therapy, all the ARs were reversed and the ATP value declined significantly compared with the control group and that on the day when AR occurred (p < 0.01). CONCLUSIONS: During the early postoperative period (especially at first week after liver transplantation), the elevation of ATP levels within CD4(+) T lymphocytes has good sensitivity and specificity in diagnosing the AR at early stage. And the degree of AR has positive relationship with ATP value. After the intravenous glucocorticoid therapy, the obvious declination of AR might be used in evaluating the effectiveness of anti-rejection treatment.