Clinical effectiveness of cell therapies in patients with chronic liver disease and acute-on-chronic liver failure: a systematic review protocol

Role of Estrogen and Estrogen Receptor in GH-Secreting Adenomas

Acromegaly is a rare disease with several systemic complications that may lead to increased overall morbidity and mortality. Despite several available treatments, ranging from transsphenoidal resection of GH-producing adenomas to different medical therapies, complete hormonal control is not achieved in some cases. Some decades ago, estrogens were first used to treat acromegaly, resulting in a significant decrease in IGF1 levels. However, due to the consequent side effects of the high dose utilized, this treatment was later abandoned. The evidence that estrogens are able to blunt GH activity also derives from the evidence that women with GH deficiency taking oral estro-progestins pills need higher doses of GH replacement therapy. In recent years, the role of estrogens and Selective Estrogens Receptor Modulators (SERMs) in acromegaly treatment has been re-evaluated, especially considering poor control of the disease under first- and second-line medical treatment. In this review, we analyze the state of the art concerning the impact of estrogen and SERMs on the GH/IGF1 axis, focusing on molecular pathways and the possible implications for acromegaly treatment.

Still 'dwelling in the possibility' - critical update on stem cell therapy for acute on chronic liver failure

Stem cells therapy could improve survival in patients with liver failure. Studies on stem cell therapy and related growth factors in decompensated cirrhosis has been on the forefront but has shown heterogenous results. Recent high-quality studies have shown a lack of efficacy and safety. Patients with acute-on-chronic liver failure (ACLF) are a unique group with high mortality in the short-term associated with rapid onset extrahepatic organ failures. In these patients, there is an urgent need to identify treatments that can improve liver cell function and mass, prevent sepsis/organ failure, ameliorate systemic inflammation, and increase transplant-free survival. Stem cells are a novel treatment in ACLF but with unclear efficacy and safety. In this narrative review, we discuss the basics of liver regeneration in patients with ACLF and update current clinical status of stem cell use in patients with ACLF for improving our understanding of future directions.

Therapeutic efficacy and safety of umbilical cord mesenchymal stem cell transplantation for liver cirrhosis in Chinese population: A meta-analysis

BACKGROUND AND OBJECTIVE

Mesenchymal stem cells transfusion has been considered as a promising option for liver cirrhosis (LC). The aim of this study was to systematically evaluate the efficacy and safety of umbilical cord mesenchymal stem cells (UMSC) combined with traditional supportive therapy (TST) for the treatment of patients with LC.

METHODS

Data was extracted from clinical trials published on Web of Science, PubMed, EMBASE, Cochrane Library, Wanfang and CNKI database. The evaluated outcome measurements included liver function, coagulation function, liver fibrosis indexes, clinical symptoms, quality of life (QOL) and adverse events.

RESULTS

A total of 14 trials including 717 LC patients met our selection criteria were involved. The liver function of LC patients was significantly improved after combined therapy (UMSC plus TST), indicated by decreased total bilirubin, alanine aminotransferase and prothrombin time, and increased serum albumin, cholinesterase and prothrombin activity. The QOL of patients was also improved after UMSC therapy. Compared with TST alone, the combined therapy showed better treatment effect based on measurements of hyaluronic acid (OR=-143.20, CI=-181.58 to -104.82, P<0.00001), laminin (OR=-50.65, CI=-53.70 to -47.61, P<0.00001), type III procollagen (OR=-8.68, CI=-9.00 to -8.36, P<0.00001), type IV collagen (OR=-105.79, CI=-132.44 to -79.14, P<0.00001) and plasma prolidase (OR=-876.54, CI=-911.89 to -840.56, P<0.00001). Moreover, the patients' clinical symptoms including fatigue (4th, P=0.003; 8th, P=0.01), appetite (4th, P<0.0001; 8th, P=0.06), ascites (4th, P=0.03; 8th, P=0.17), and abdominal distension (4th, P=0.0008; 8th, P=0.64) were also improved in patients treated by combined therapy without adverse events observed.

CONCLUSION

UMSC and TST combined therapy for LC patients improved their liver function, clinical symptoms and QOL without severe adverse events, therefore is safe and effective in LC therapy.

Mesenchymal Stem Cell Transplantation for Liver Cell Failure: A New Direction and Option

Background and Aims

Mesenchymal stem cell transplantation (MSCT) became available with liver failure (LF), while the advantages of MSCs remain controversial. We aimed to assess clinical advantages of MSCT in patients with LF.

Methods

Clinical researches reporting MSCT in LF patients were searched and included.

Results

Nine articles (n = 476) related with LF patients were enrolled. After MSCT, alanine aminotransferase (ALT) baseline decreased largely at half a month (P < 0.05); total bilirubin (TBIL) baseline declined to a certain stable level of 78.57 μmol/L at 2 and 3 months (P < 0.05). Notably, the decreased value (D value) of Model for End-Stage Liver Disease score (MELD) of acute-on-chronic liver failure (ACLF) group was higher than that of chronic liver failure (CLF) group (14.93 ± 1.24 versus 4.6 ± 5.66, P < 0.05). Moreover, MELD baseline of ≥20 group was a higher D value of MELD than MELD baseline of <20 group with a significant statistical difference after MSCT (P = 0.003).

Conclusion

The early assessment of the efficacy of MSCT could be based on variations of ALT at half a month and TBIL at 2 and 3 months. And it had beneficial effects for patients with LF, especially in ACLF based on the D value of MELD.

Umbilical cord blood stem cells transplantation as an adjunctive treatment strategy for liver cirrhosis in Chinese population: a meta-analysis of effectiveness and safety

Objective

The aim of the study was to evaluate the efficacy and safety of umbilical cord blood stem cells (USCs) transplantation combined with routine supportive therapy (RST) for liver cirrhosis (LC).

Materials and methods

Clinical trials involved in this research were searched from Web of Science, PubMed, EMBASE, Cochrane Library, Wanfang and CNKI database. Treatment effects, quality of life (QoL), adverse events and other outcome measures were extracted and evaluated.

Results

A total of 10 trials including 616 LC patients were involved in this study. Based on our analysis, the liver function of LC patients was significantly improved after USCs transplantation and RST combined therapy, indicated by decreased total bilirubin, alanine aminotransferase, aspartate aminotransferase levels and prothrombin time and increased serum albumin level and prothrombin activity. Compared to those treated by RST alone, patients treated by combined therapy showed more satisfied treatment effects, improved QoL reflected by improved appetite (odds ratio [OR]=5.43, 95% CI=2.84 to 10.38, P<0.00001) and relieved fatigue (OR=4.33, 95% CI=0.87 to 21.60, P=0.07), ascetic fluid (OR=4.56, 95% CI=2.69 to 7.74, P<0.00001), abdominal distension (OR=4.01, 95% CI=1.34 to 12.02, P=0.01) and edema (OR=2.69, 95% CI=0.23 to 31.72, P=0.43). No serious adverse events occurred during USCs therapy.

Conclusion

USCs transplantation is a safe and effective adjuvant therapy for RST-treated LC, possibly through improving patients’ liver function.

Historical Perspectives and Advances in Mesenchymal Stem Cell Research for the Treatment of Liver Diseases

Liver transplantation is the only effective therapy for patients with decompensated cirrhosis and fulminant liver failure. However, due to a shortage of donor livers and complications associated with immune suppression, there is an urgent need for new therapeutic strategies for patients with end-stage liver diseases. Given their unique function in self-renewal and differentiation potential, stem cells might be used to regenerate damaged liver tissue. Recent studies have shown that stem cell-based therapies can improve liver function in a mouse model of hepatic failure. Moreover, acellular liver scaffolds seeded with hepatocytes produced functional bioengineered livers for organ transplantation in preclinical studies. The therapeutic potential of stem cells or their differentiated progenies will depend on their capacity to differentiate into mature and functional cell types after transplantation. It will also be important to devise methods to overcome their genomic instability, immune reactivity, and tumorigenic potential. We review directions and advances in the use of mesenchymal stem cells and their derived hepatocytes for liver regeneration. We also discuss the potential applications of hepatocytes derived from human pluripotent stem cells and challenges to using these cells in treating end-stage liver disease.

Adipose-derived mesenchymal stem cells promote liver regeneration and suppress rejection in small-for-size liver allograft

Adipose-derived mesenchymal stem cells (ADSCs) possess a liver regeneration capacity and immunosuppressive activity and hold promise in autologous cell-based technology. This study aimed to determine whether autologous ADSCs can improve outcomes in the rat reduced size liver transplantation model. Allogeneic 50% orthotopic liver transplantation followed by administration of autologous ADSCs delivered into the portal vein system was conducted in LEW donor rats and BN recipient rats with phosphate buffered solution (PBS) infusion used as the control. Liver grafts and recipient serum were obtained. We assessed histopathology, regeneration, apoptosis, serum liver enzymes, serum cytokines, and circulating regulatory T cells (Tregs) on postoperative day (POD) 7 and 14. It was found that ADSCs significantly reduced acute rejection and improved the allograft's survival times (median, 24days). Liver function, as assessed by the levels of alanine aminotransferase, aspartate aminotransferase, total bilirubin, as well as liver apoptosis was significantly alleviated in the ADSC group compared with the control group. In addition, ADSC therapy markedly promoted the expression of PCNA in the allograft. Furthermore, levels of interleukin (IL)-10 and transforming growth factor (TGF)-β1 were significantly elevated, whereas those of IL-2 and IL-17 levels were significantly reduced in the ADSC group when compared to the control group. Moreover, flow cytometry analysis revealed that peripheral Tregs had been significantly increased by the infusion of ADSCs. These results demonstrate that implanted autologous ADSCs improve allogeneic reduced size liver allograft outcomes by attenuating acute rejection and reducing inflammatory responses, as well as enhancing liver regeneration.

Catheter-directed Intraportal Delivery of Endothelial Cell Therapy for Liver Regeneration: A Feasibility Study in a Large-Animal Model of Cirrhosis

Purpose To demonstrate the feasibility of imaging-guided catheter-directed delivery of endothelial cell therapy in a porcine model of cirrhosis for liver regeneration. Materials and Methods After approval from the institutional animal care and use committee, autologous liver endothelial cells were grown from core hepatic specimens from swine. Cirrhosis was induced in swine by means of transcatheter infusion of ethanol and iodized oil into the hepatic artery. Three weeks after induction of cirrhosis, the swine were randomly assigned to receive autologous cell therapy (endothelial cells, n = 4) or control treatment (phosphate-buffered saline, n = 4) by means of imaging-guided transhepatic intraportal catheterization. Fluorescence-activated cell sorting analysis was performed on biopsy samples 1 hour after therapy. Three weeks after intraportal delivery of endothelial cells, the swine were euthanized and the explanted liver underwent quantitative pathologic examination. Statistical analysis was performed with an unpaired t test by using unequal variance. Results Liver endothelial cells were successfully isolated, cultured, and expanded from eight 20-mm, 18-gauge hepatic core samples to 50 × 10⁶ autologous cells per pig. Intraportal delivery of endothelial cell therapy or saline was technically successful in all eight swine, with no complications. Endothelial cells were present in the liver for a minimum of 1 hour after intraportal infusion. Swine treated with endothelial cell therapy showed mean levels of surrogate markers of hepatobiliary injury that were consistent with decreases in hepatic fibrosis and biliary ductal damage relative to the control animals, although statistical significance was not met in this pilot study: The mean percentage of positive pixels at Masson trichrome staining was 7.28% vs 5.57%, respectively (P = .20), the mean proliferation index with cytokeratin wide-spectrum was 2.55 vs 1.13 (P = .06), and the mean proliferation index with Ki67 was 7.08 vs 4.96 (P = .14). Conclusion The results confirm the feasibility of imaging-guided catheter-directed endothelial cell therapy with an intraportal technique for the treatment of cirrhosis in a porcine model. A trend toward decreased liver fibrosis with endothelial cell therapy was observed. Larger animal studies and human studies are necessary to confirm significance. ^© RSNA, 2017.

Status of and candidates for cell therapy in liver cirrhosis: overcoming the "point of no return" in advanced liver cirrhosis

The treatment of liver cirrhosis is currently being standardized and developed specifically to reduce activation of hepatic stellate cells (HSCs), inhibit fibrosis, increase degradation of matrix components, and reduce activated myofibroblasts. Cell therapy can be applied in the treatment of liver cirrhosis; however, the characteristic features of this therapy differ from those of other treatments because of the involvement of a living body origin and production of multiple cytokines, chemokines, matrix metalloproteinases (MMPs), and growth factors. Thus, cell therapies can potentially have multiple effects on the damaged liver, including alleviating liver cirrhosis and stimulating liver regeneration with affecting the host cells. Cell therapies initially involved autologous bone marrow cell infusion, and have recently developed to include the use of specific cells such as mesenchymal stem cells and macrophages. The associated molecular mechanisms, routes of administration, possibility of allogeneic cell therapy, and host conditions appropriate for cell therapies are now being extensively analyzed. In this review, we summarize the status and future prospects of cell therapy for liver cirrhosis.

Molecular Imaging of Stem Cell Transplantation for Liver Diseases: Monitoring, Clinical Translation, and Theranostics

Stem cell transplantation has been investigated to rescue experimental liver failure and is promising to offer an alternative therapy to liver transplantation for liver diseases treatment. Several clinical studies in this field have been carried out, but the therapeutic benefit of this treatment is still controversial. A major obstacle to developing stem cell therapies in clinic is being able to visualize the cells in vivo. Imaging modalities allow optimization of delivery, detecting cell survival and functionality by in vivo monitoring these transplanted graft cells. Moreover, theranostic imaging is a brand new field that utilizes nanometer-scale materials to glean diagnostic insight for simultaneous treatment, which is very promising to improve stem cell-based therapy for treatment of liver diseases. The aim of this review was to summarize the various imaging tools that have been explored with advanced molecular imaging probes. We also outline some recent progress of preclinical and clinical studies of liver stem cells transplantation. Finally, we discuss theranostic imaging for stem cells transplantation for liver dysfunction and future opportunities afforded by theranostic imaging.