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Recently, attentions have come to the alleviatory effect of protein inhibitor of activated STAT1 (PIAS1) in hepatic ischemia-reperfusion injury (HIRI), but the underlying molecular mechanistic actions remain largely unknown, which were illustrated in the present study. Microarray-based analysis predicted a possible regulatory mechanism involving the PIAS1/NFATc1/HDAC1/IRF-1/p38 MAPK signaling axis in HIRI. Then, growth dynamics of hypoxia/reoxygenation- (H/R-) exposed hepatocytes and liver injury of HIRI-like mice were delineated after the alteration of the PIAS1 expression. We validated that PIAS1 downregulation occurred in H/R-exposed hepatocytes and HIRI-like mice, while the expression of NFATc1, HDAC1, and IRF-1 and phosphorylation levels of p38 were increased. PIAS1 inactivated p38 MAPK signaling by inhibiting HDAC1-mediated IRF-1 through NFATc1 SUMOylation, thereby repressing the inflammatory response and apoptosis of hepatocytes in vitro, and alleviated liver injury in vivo. Collectively, the NFATc1/HDAC1/IRF-1/p38 MAPK signaling axis is highlighted as a promising therapeutic target for potentiating hepatoprotective effects of PIAS1 against HIRI.

// Kuijie Liu 1 , Hongliang Yao 1 , Sanlin Lei 1 , Li Xiong 1 , Haizhi Qi 1 , Ke Qian 1 , Jiqiang Liu 1 , Peng Wang 1 , Hua Zhao 1 1 Department of General Surgery, The Second Xiangya Hospital, Central South University, Changsha 410011, China Correspondence to: Hua Zhao, email: drzhaohua2012@163.com Keywords: miR-124, p63, feedback loop, cell growth, colorectal cancer Received: May 26, 2016 Accepted: February 20, 2017 Published: March 16, 2017 ABSTRACT Among the diverse co-regulatory relationships between transcription factors (TFs) and microRNAs (miRNAs), feedback loops have received the most extensive research attention. The co-regulation of TFs and miRNAs plays an important role in colorectal cancer (CRC) growth. Here, we show that miR-124 can regulate two isoforms of p63, TAp63 and ΔNp63, via iASPP, while p63 modulates signal transducers and activators of transcription 1 (STAT1) expression by targeting miR-155. Moreover, STAT1 acts as a regulator of CRC growth by targeting miR-124. Taken together, these results reveal a feedback loop between miRNAs and TFs. This feedback loop comprises miR-124, iASPP, STAT1, miR-155, TAp63 and ΔNp63, which are essential for CRC growth. Moreover, this feedback loop is perturbed in human colon carcinomas, which suggests that the manipulation of this microRNA-TF feedback loop has therapeutic potential for CRC.

We investigated in vitro whether HLA highly sensitized patients with end-stage renal disease will be disadvantaged immunologically after a genetically engineered pig kidney transplant.Blood was drawn from patients with a calculated panel-reactive antibody (cPRA) 99% to 100% (Gp1, n = 10) or cPRA 0% (Gp2, n = 12), and from healthy volunteers (Gp3, n = 10). Serum IgM and IgG binding was measured (i) to galactose-α1-3 galactose and N-glycolylneuraminic acid glycans by enzyme-linked immunosorbent assay, and (ii) to pig red blood cell, pig aortic endothelial cells, and pig peripheral blood mononuclear cell from α1,3-galactosyltransferase gene-knockout (GTKO)/CD46 and GTKO/CD46/cytidine monophosphate-N-acetylneuraminic acid hydroxylase-knockout (CMAHKO) pigs by flow cytometry. (iii) T-cell and B-cell phenotypes were determined by flow cytometry, and (iv) proliferation of T-cell and B-cell carboxyfluorescein diacetate succinimidyl ester-mixed lymphocyte reaction.(i) By enzyme-linked immunosorbent assay, there was no difference in IgM or IgG binding to galactose-α1-3 galactose or N-glycolylneuraminic acid between Gps1 and 2, but binding was significantly reduced in both groups compared to Gp3. (ii) IgM and IgG binding in Gps1 and 2 was also significantly lower to GTKO/CD46 pig cells than in healthy controls, but there were no differences between the 3 groups in binding to GTKO/CD46/CMAHKO cells. (iii and iv) Gp1 patients had more memory T cells than Gp2, but there was no difference in T or B cell proliferation when stimulated by any pig cells. The proliferative responses in all 3 groups were weakest when stimulated by GTKO/CD46/CMAHKO pig peripheral blood mononuclear cell.(i) End-stage renal disease was associated with low antipig antibody levels. (ii) Xenoreactivity decreased with increased genetic engineering of pig cells. (iii) High cPRA status had no significant effect on antibody binding or T-cell and B-cell response.

The results of the assay for measuring anti-non-Gal antibodies (which affect pig xenograft survival) in recipients are important. Serum incubation time and concentration may be important factors in the extent of antibody binding to the graft. The aim of this in vitro study was to determine the optimal incubation time and serum concentration for measuring anti-non-Gal antibody binding to porcine aortic endothelial cells (pAECs). Pooled human, naive, and sensitized baboon sera were incubated with wild-type, α1,3-galactosyltransferase gene-knockout (GTKO), and GTKO/human CD55 pAECs. IgM/IgG binding to pAECs after varying serum incubation times (0.5, 1, 2, and 3 hour) and concentrations (5, 10, 20, and 40 μL) was determined by flow cytometry. An increase in incubation time from 30 minutes to 2 hour was associated with increases in anti-non-Gal IgM/IgG binding to GTKO and GTKO/hCD55 pAECs of pooled human, naive and sensitized baboon sera (P

Background The transcription factor forkhead box P3 (Foxp3) is a master regulatory gene necessary for the development and function of CD4+CD25+ regulatory T cells (Tregs). Mesenchymal stem cells (MSC) have recently emerged as promising candidates for cell-based immunosuppression/tolerance induction protocols. Thus, we hypothesized that MSC-based Foxp3 gene therapy would improve immunosuppressive capacity of MSC and induce donor-specific allograft tolerance in rat’s liver allograft model. Methods The present study utilized a lentivirus vector to overexpress the therapeutic gene Foxp3 on MSC. In vivo, Injections of 2 × 106 MSC, FUGW-MSC or Foxp3-MSC into the portal vein were carried out immediately after liver transplantation. Results Successful gene transfer of Foxp3 in MSC was achieved by lentivirus carrying Foxp3 and Foxp3-MSC engraftment in liver allograft was confirmed by fluorescence microscopy. Foxp3-MSC treatment significantly inhibited the proliferation of allogeneic ACI CD4+ T cells to splenocytes (SC) from the same donor strain or third-party BN rat compared with MSC. Foxp3-MSC suppressive effect on the proliferation of CD4+ T cells is contact dependent and associated with Programmed death ligand 1(PD-L1) upregulation in MSC. Co-culture of CD4+ T cells with Foxp3-MSC results in a shift towards a Tregs phenotype. More importantly, Foxp3-MSC monotherapy achieved donor-specific liver allograft tolerance and generated a state of CD4+CD25+Foxp3+ Tregs-dependent tolerance. Conclusion Foxp3-engineered MSC therapy seems to be a promising and attractive cell therapy approach for inducing immunosuppression or transplant tolerance.

To explore the protective eff ect of minocycline on hepatic ischemia-reperfusion injury (IRI) in rats and the underlying mechanisms.A total of 54 male Sprague-Dawley rats were randomly divided into 3 groups: the sham-operated group (control group), the ischemic-reperfusion (IR group), and the minocycline preconditioning group (n=18 per group). The rats in the minocycline preconditioning group were given minocycline (45 mg/kg) by gastric irrigation at 36 h before operation and then were subsequently administered with minocycline (22.5 mg/kg) at every 12 h. Th e rats were sacrifi ced at 2, 6, 24 h after reperfusion. The serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST) and lactate dehydrogenase (LDH) were measured. HE staining of liver tissues was performed to detect the histological changes, and the degree of liver IRI according to Suzuki score were calculated. The levels of malondialdehyde (MDA) and myeloperoxidase (MPO) were determined by spectrophotometer; the mRNA expression of tumor necrosis factor-α (TNF-α) and interleukin-1 beta (IL-1β) in the liver were measured by real-time PCR; Dickkopf-1 (DKK-1) and beta-catenin (β-catenin) protein expression in the liver were detected by Western blot.After 2, 6, 24 h reperfusion, compared with the IR group, the liver function (ALT, AST and LDH) in the minocycline group was significantly improved (all P0.05); the Suzuki's scores and the levels of hepatic TNF-α and IL-1β mRNA were significantly decreased (all P0. 05); the MDA and MPO levels the liver were decreased (both P0.05); the protein expression of hepatic DKK-1 was decreased (P0.05), while the protein expression of β-catenin was increased (P0.05).Minocycline can alleviate the ischemic-reperfusion injury mainly through reducing oxidative stress and inhibiting the release of pro-inflammatory cytokines depends on the activation of the Wnt/β-catenin signaling pathway in the liver.

To investigate the expression of T helper (Th) 17 cells and the related interleukin 17 (IL-17) in acute renal allograft rejection in mice and its significance.We established a mouse renal allograft model, in which mice were randomly divided into a renal isograft group and an acute renal allograft rejection group. Three and 7 d after the transplantation, the serum interferon (IFN)-γ and IL-17 levels in the mice were determined by enzyme-linked immunosorbent assay, the percentage of Th1 and Th17 cells in the total kidney-infiltrating lymphocytes was investigated by flow cytometry, and the transplanted kidney species were given routine pathological examination after fixation with 10% formalin.Compared with the isograft group, the allograft mice showed a significantly higher content of IL-17 (P0.05) but not IFN-γ in the serum 3 d after transplantation, and showed significantly higher serum IL-17 and IFN-γ contents 7 d after transplantation (P0.05). Also, compared with the isograft group, the allograft mice exhibited significantly higher percentage of Th1 and Th17 cells on both day 3 and day 7 (P0.05). In the allograft group, the contents of serum IFN-γ and IL-17 and the percentage of Th1 and Th17 cells were significantly higher on day 7 than on day 3 (P0.05). Routine pathological examination indicated that, as time passed, the allograft mice showed gradually stronger rejection responses.Th17 cells might play an important role in the development of acute renal allograft rejection, and IL-17 can be used as an early indicator of acute rejection.

To investigate the surgical procedures of orthotopic small bowel transplantation (SBT) model in mice to study the function and rejection of SBT.We established a mouse SBT allograft model as follows: the donor portal vein was anastomosed end by side with the recipient inferior vena cava; the donor superior mesenteric artery with aorta patch was anastomosed end by side with recipient abdominal aorta. After an appropriate length of the recipient's small bowel was removed, the donor's small bowel and the recipient's small bowel were end-to-end anastomosed discontinuously. The mice were fasted for 4 d after the operation, free access to water and subcutaneously injection of 2 mL of 5% glucose saline twice daily. Operation success was regarded as survival for more than 5 d. There is no antibiotic and immunosuppressor.A total of 30 transplantations were done, the 5 d survival rate was 60% (18/30), and 12 died within 5 d. Among the dead recipients, 5 died of arterial anastomotic stenosis and anastomotic thrombosis, 2 of hemorrhagic shock caused by anastomotic bleeding, and the other 5 of intra-abdominal infection caused by postoperative intestinal fistula. The donors' operative time was (40 ± 4.5) min, warm ischemia time was about 0.5 min, donor preparation time was about 3 min, and cold preservation time was (30 ± 7.5) min. The recipients' operative time was (95 ± 8.0) min, among which, the abdominal aorta and inferior vena cava clamping time was (38 ± 3.5) min, the venous anastomotic time was (10 ± 2.0) min and the arterial anastomotic time was (15 ± 3.0) min. The mean intra-operative blood loss of the surviving recipient mice was about 0.2 mL.High quality vascular anastomosis, and rehydration of donors and recipients are crucial factors for improving the success rate of SBT.