Clinical outcomes of the transplantation of stem cells from various human tissue sources in the management of liver cirrhosis: a systematic review and meta-analysis

Comparative Efficacy of Endogenous Stem Cells Recruiting Hydrogels and Stem Cell-loaded Hydrogels in Knee Cartilage Regeneration: A Meta- analysis

BACKGROUND

Cartilage defects remain a challenge in diseases such as osteoarthritis (OA) and fractures. Scientists have explored the use of hydrogels in conjunction with stem cell technology as a tissue engineering method to treat cartilage defects in joints. In recent years, research into hydrogels containing stem cell technology for cartilage repair has mainly focused on two categories: stem cell-loaded hydrogels and endogenous stem cell recruiting hydrogels. The latter, utilizing cell-free products, represents a novel concept with several advantages, including easier dose standardization, wider sources, and simpler storage. This meta-analysis aims to assess and compare the therapeutic effects of endogenous stem cell recruiting hydrogels and stem cell-loaded hydrogels in promoting articular cartilage regeneration in animal models, with the goal of exploring endogenous stem cell recruiting hydrogels as a promising replacement therapy for knee cartilage regeneration in preclinical animal studies.

METHODS

We systematically searched PubMed, Web of Science, Cochrane Library, and Embase until January 2023 using key words related to stem cells, cartilage regeneration and hydrogel. A random-effects meta-analysis was performed to evaluate the therapeutic effect on newborn cartilage formation. Stratified analyses were also carried out by independently classifying trials according to similar characteristics. The level of evidence was determined using the GRADE method.

RESULTS

Twenty-eight studies satisfied the inclusion criteria. Comprehensive analyses revealed that the use of endogenous stem cell recruiting hydrogels significantly promoted the formation of new cartilage in the knee joint, as evidenced by the histological score (3.77, 95% CI 2.40, 5.15; p < 0.0001) and the International Cartilage Repair Society (ICRS) macroscopic score (3.00, 95% CI 1.83, 4.18; p = 0.04), compared with the control group. The stem cell-loaded hydrogels also increased cartilage regeneration in the knee with the histological score (3.13, 95% CI 2.22, 4.04; p = 0.02) and the ICRS macroscopic score (2.49, 95% CI 1.16, 3.82; p = 0.03) in comparison to the control. Significant heterogeneity between studies was observed, and further stratified and sensitivity analyses identified the transplant site and modelling method as the sources of heterogeneity.

CONCLUSION

The current study indicates that both endogenous stem cell recruiting hydrogels and stem cell loaded hydrogels can effectively promote knee joint cartilage regeneration in animal trials.

Cell transplantation-based regenerative medicine in liver diseases

This review aims to evaluate the current preclinical state of liver bioengineering, the clinical context for liver cell therapies, the cell sources, the delivery routes, and the results of clinical trials for end-stage liver disease. Different clinical settings, such as inborn errors of metabolism, acute liver failure, chronic liver disease, liver cirrhosis, and acute-on-chronic liver failure, as well as multiple cellular sources were analyzed; namely, hepatocytes, hepatic progenitor cells, biliary tree stem/progenitor cells, mesenchymal stromal cells, and macrophages. The highly heterogeneous clinical scenario of liver disease and the availability of multiple cellular sources endowed with different biological properties make this a multidisciplinary translational research challenge. Data on each individual liver disease and more accurate endpoints are urgently needed, together with a characterization of the regenerative pathways leading to potential therapeutic benefit. Here, we critically review these topics and identify related research needs and perspectives in preclinical and clinical settings.

Human Umbilical Cord Blood-Derived Mesenchymal Stem Cell Transplantation for Patients with Decompensated Liver Cirrhosis

BACKGROUND OR PURPOSE

Although human umbilical cord blood-derived mesenchymal stem cell transplantation (HUCB-MSCT) resulted in a good short-term therapeutic effect on patients with decompensated liver cirrhosis (DLC), the long-term survival remained unclear. This study aimed to evaluate the impact of HUCB-MSCT on long-term outcomes in patients with DLC.

METHODS

This retrospective cohort study included hospitalized patients with decompensated cirrhosis in Liuzhou Hospital of Traditional Chinese Medicine between November 2010 and February 2013. The primary outcome was overall survival (OS). The secondary outcomes were 3-year and 5-year survival rates and the occurrence rate of hepatocellular carcinoma (HCC).

RESULTS

A total of 201 subjects were enrolled, including 36 patients who underwent HUCB-MSCT (SCT group) and 165 patients who did not (non-SCT group). After PSM (1:2), there were 36 patients in the SCT group and 72 patients in non-SCT group. The 3-year and 5-year survival rates of the two groups were 83.3% vs. 61.8% and 63.9% vs. 43.6%, and median OS time was 92.50 and 50.80 months, respectively. HUCB-MSCT treatment was found to be an independent beneficial factor for patient OS (hazard ratio = 0.47; 95% CI: 0.29-0.76; P = 0.002). There was no significant difference in the occurrence rate of HCC between the two groups (P = 0.410).

DISCUSSION OR CONCLUSIONS

HUCB-MSCT may improve long-term OS without increasing the occurrence of HCC in patients with DLC.

TRIAL REGISTRATION

The Chinese Clinical Trial Registry (ChiCTR2100047550).

Human stem cells for decompensated cirrhosis in adults

This is a protocol for a Cochrane Review (intervention). The objectives are as follows:

To assess the benefits and harms of stem cell treatment in adults with decompensated cirrhosis, regardless of ethnicity, sex, types of stem cells, route of stem cell injection, and administered dose.

Regenerative medicine technologies applied to transplant medicine. An update

Regenerative medicine (RM) is changing how we think and practice transplant medicine. In regenerative medicine, the aim is to develop and employ methods to regenerate, restore or replace damaged/diseased tissues or organs. Regenerative medicine investigates using tools such as novel technologies or techniques, extracellular vesicles, cell-based therapies, and tissue-engineered constructs to design effective patient-specific treatments. This review illustrates current advancements in regenerative medicine that may pertain to transplant medicine. We highlight progress made and various tools designed and employed specifically for each tissue or organ, such as the kidney, heart, liver, lung, vasculature, gastrointestinal tract, and pancreas. By combing both fields of transplant and regenerative medicine, we can harbor a successful collaboration that would be beneficial and efficacious for the repair and design of de novo engineered whole organs for transplantations.

Autologous bone marrow cell transplantation in the treatment of HIV patients with compensated cirrhosis

Liver stem cell therapy is a promising tool to improve decompensated liver cirrhosis (DLC). Especially in patients infected with human immunodeficiency virus (HIV), the condition of the liver may be aggravated by antiretroviral therapy. A total of 21 patients diagnosed with DLC and HIV infection were divided into two groups as follows: those who received (combination therapy group, 14 patients) and those who did not receive (routine therapy group, 7 patients) bone marrow cell transplantation through the portal vein. Two patients died of surgery-related complications in the combination therapy group. The results showed that the survival rate was 85.7% in the combination therapy group after 2 years of follow-up, which was significantly higher than the 14.3% in the conventional therapy group (P<0.01). After treatment, the liver function score decreased significantly in the combination therapy group at 1 (t = 4.276, P = 0.000), 3 (t = 9.153, P = 0.000), and 12 (t = 13.536, P = 0.000) months, the levels of albumin were significantly increased, and the total bilirubin level and prothrombin time were significantly reduced or shortened as compared with the routine therapy group (P<0.05 or <0.01). The white blood cell count, hemoglobin, platelet count, and CD4+ and CD8+ levels were significantly higher in the combination therapy group at different time points as compared with the routine therapy group (P<0.05 or <0.01). In summary, the combination therapy is effective in HIV-infected patients with DLC and useful for the recovery of liver function and cellular immune function but may increase the risk of severe complications after surgery.

Distinct EpCAM-Positive Stem Cell Niches Are Engaged in Chronic and Neoplastic Liver Diseases

In normal human livers, EpCAM^pos cells are mostly restricted in two distinct niches, which are (i) the bile ductules and (ii) the mucous glands present inside the wall of large intrahepatic bile ducts (the so-called peribiliary glands). These EpCAM^pos cell niches have been proven to harbor stem/progenitor cells with great importance in liver and biliary tree regeneration and in the pathophysiology of human diseases. The EpCAM^pos progenitor cells within bile ductules are engaged in driving regenerative processes in chronic diseases affecting hepatocytes or interlobular bile ducts. The EpCAM^pos population within peribiliary glands is activated when regenerative needs are finalized to repair large intra- or extra-hepatic bile ducts affected by chronic pathologies, including primary sclerosing cholangitis and ischemia-induced cholangiopathies after orthotopic liver transplantation. Finally, the presence of distinct EpCAM^pos cell populations may explain the histological and molecular heterogeneity characterizing cholangiocarcinoma, based on the concept of multiple candidate cells of origin. This review aimed to describe the precise anatomical distribution of EpCAM^pos populations within the liver and the biliary tree and to discuss their contribution in the pathophysiology of human liver diseases, as well as their potential role in regenerative medicine of the liver.

Efficacy and safety of stem cells transplantation in patients with type 1 diabetes mellitus-a systematic review and meta-analysis

Stem cells (SCs) therapy is a new promising therapeutic modality for type 1 diabetes (T1DM). We performed a systematic review and meta-analysis to evaluate the efficacy and safety of stem cells transplantation (SCT) in patients with T1DM. We searched five literature databases (MEDLINE, EMBASE, Web of Science, WanFang and CENTRAL) up to 31 October 2019. 29 studies (487 patients with T1DM) were included in our meta-analysis. There was no substantial publication bias. Meta-analysis showed the SCT had significant effect to decrease HbA1c (SMD, 1.40; 95% CI, 0.93 to 1.86; p < 0.00001; I² = 89%) and to improve C-peptide levels (SMD, -0.62; 95% CI, -1.22 to -0.02; p = 0.04; I² = 92%) at 1 year follow-up. Subgroup analyses showed the heterogeneity level of the results was high. Significant improvement of metabolic outcomes was observed in the subgroups of mesenchymal stem cells (MSCs) combined with hematopoietic stem cells (HSCs) and HSCs. The older age showed significant association with the efficacy in HSCs subgroup. The higher GADA positive rate before treatment also significantly associated with the decrease of daily insulin requirement. The transient insulin independence rate at last follow-up was 9.6 per 100 person-years (95% CI: 5.8-13.5%). The mean length of insulin independence was 15.6 months (95% CI: 12.3-18.9). The mortality of SCT was 3.4% (95% CI: 2.1-5.5%). Therefore, SCT is an efficacious and safe method for treating patients with T1DM especially in the subgroups of MSCs + HSCs and HSCs. Well designed, double blind and randomized controlled trails with large sample size and long-term follow-up are needed for further evaluation.

Transplantation with GXHPC1 for Liver Cirrhosis: Phase 1 Trial

Currently, the only effective therapy for cirrhosis of the liver is liver transplantation. However, finding a compatible liver is difficult due to the low supply of healthy livers and the ever-increasing demand. However, stem-cell therapy may offer a solution for liver cirrhosis; for example, GXHPC1 therapy preparation contains adipose-derived mesenchymal stem cells (AD-MSCs) and was developed for the treatment of liver cirrhosis. In our previous report, animal studies suggested that treatment of a diseased liver via GXHPC1 transplantation can abrogate liver fibrosis and facilitate recovery of liver function. In our current human trial, patients with liver cirrhosis were included. Their adipose tissue was harvested from the subcutaneous fat of the abdominal wall during surgery. AD-MSCs were cultured and suspended at a concentration of 100 million cells in 1 ml of physiological saline (i.e., GXHPC1). This human study passed the Taiwan Food and Drug Administration IND inspection and received Phase I clinical trial permission. The trial was conducted with six patients with liver cirrhosis to demonstrate the safety and efficacy of administering GXHPC1. Intrahepatic injection of GXHPC1 did not cause any safety issues in the analysis of adverse drug reactions and suspected unexpected serious adverse reactions, and showed a tendency for improvement of liver function, METAVIR score, Child–Pugh score, MELD score, and quality of life for patients with liver cirrhosis.

Mechanisms Underlying Cell Therapy in Liver Fibrosis: An Overview

Fibrosis is a common feature in most pathogenetic processes in the liver, and usually results from a chronic insult that depletes the regenerative capacity of hepatocytes and activates multiple inflammatory pathways, recruiting resident and circulating immune cells, endothelial cells, non-parenchymal hepatic stellate cells, and fibroblasts, which become activated and lead to excessive extracellular matrix accumulation. The ongoing development of liver fibrosis results in a clinically silent and progressive loss of hepatocyte function, demanding the constant need for liver transplantation in clinical practice, and motivating the search for other treatments as the chances of obtaining compatible viable livers become scarcer. Although initially cell therapy has emerged as a plausible alternative to organ transplantation, many factors still challenge the establishment of this technique as a main or even additional therapeutic tool. Herein, the authors discuss the most recent advances and point out the corners and some controversies over several protocols and models that have shown promising results as potential candidates for cell therapy for liver fibrosis, presenting the respective mechanisms proposed for liver regeneration in each case.

Functions and the Emerging Role of the Foetal Liver into Regenerative Medicine

During foetal life, the liver plays the important roles of connection and transient hematopoietic function. Foetal liver cells develop in an environment called a hematopoietic stem cell niche composed of several cell types, where stem cells can proliferate and give rise to mature blood cells. Embryologically, at about the third week of gestation, the liver appears, and it grows rapidly from the fifth to 10th week under WNT/β-Catenin signaling pathway stimulation, which induces hepatic progenitor cells proliferation and differentiation into hepatocytes. Development of new strategies and identification of new cell sources should represent the main aim in liver regenerative medicine and cell therapy. Cells isolated from organs with endodermal origin, like the liver, bile ducts, and pancreas, could be preferable cell sources. Furthermore, stem cells isolated from these organs could be more susceptible to differentiate into mature liver cells after transplantation with respect to stem cells isolated from organs or tissues with a different embryological origin. The foetal liver possesses unique features given the co-existence of cells having endodermal and mesenchymal origin, and it could be highly available source candidate for regenerative medicine in both the liver and pancreas. Taking into account these advantages, the foetal liver can be the highest potential and available cell source for cell therapy regarding liver diseases and diabetes.

Pre-activation of TLR3 enhances the therapeutic effect of BMMSCs through regulation the intestinal HIF-2α signaling pathway and balance of NKB cells in experimental alcoholic liver injury

Increased intestinal permeability and immune disorder are important mechanisms of alcoholic liver disease (ALD). Recent evidences suggest bone marrow derived mesenchymal stem cells (BMMSCs) have protective effects on end-stage liver disease and intestinal barrier injury. Moreover, the activation of toll-like receptor 3 (TLR3) has been shown enhancing therapeutic effects of BMMSCs in inflammatory bowel disease (IBD). However, the mechanism remains unclear. In current study, chronic-binge alcohol abuse model was employed to investigate the therapeutic effects of BMMSCs and BMMSCs pre-activated with TLR3 (P-BMMSCs) on alcohol-induced liver and intestine damage. C57BL/6 mice were divided into four groups with normal control, alcohol-fed model, alcohol-fed model with BMMSCs treatment and alcohol-fed model with P-BMMSCs treatment. Alcohol-fed mice were fed Lieber-DeCali diet containing 5% alcohol for four weeks and given alcohol intragastrically on the 28th day, but control group were fed isocaloric diet. BMMSCs and P-BMMSCs were injected into the treatment group three times. Results showed alcohol diet causing significant damage to intestinal barrier and liver. These were reversed by the treatment of BMMSCs, especially P-BMMSCs. Moreover, alcohol increased the expression of intestinal HIF-2α, the proportion of NKB cells and the level of serum IL-18, while BMMSCs or P-BMMSCs reduced these factors. In conclusion, BMMSCs, especially TLR3 pre-activated BMMSCs could be used to protect alcohol-induced intestine and liver injury.

Stem cell transplantation for the treatment of patients with type 1 diabetes mellitus: A meta-analysis

The efficacy of stem cell (SC) transplantation in patients with type 1 diabetes mellitus (T1DM) has remained to be fully elucidated. In the present study, a systematic review and meta-analysis was performed to determine the clinical outcomes. Electronic databases, including PubMed, MEDLINE, WanFang and the Cochrane Library were screened for relevant studies published until January 13, 2018. The references of retrieved papers, systematic reviews and trial registries were manually screened for additional papers. Two authors were involved in screening the titles in order to select eligible studies, extract data and assess the risk of bias. Studies were pooled using a random-effects model as well as the Begg's funnel plot and subgroup analysis was performed using Stata 14.0 software. A total of 47 studies were retrieved for detailed evaluation, of which 22 met the inclusion criteria. No substantial publication bias was identified. The meta-analysis revealed that SC therapy increased C-peptide levels when compared with placebo treatment in randomized-controlled trials [RCT; standardized mean difference (SMD), 0.93; 95% confidence interval (CI) 0.23-1.63] and self-controlled trials (SMD, 0.66; 95% CI, -0.22 to 1.54). An analysis demonstrated that SC therapy was more efficient at reducing the glycated hemoglobin level compared with the control group in RCTs (SMD, 0.56; 95% CI; 0.06-1.06; and SMD, 1.63; 95% CI, 0.92-2.34, respectively). The graphs demonstrated that SC transplantation resulted in a reduction of insulin requirement. Furthermore, subgroup analyses revealed that patient age, medical history and the SC injection dose may be sources of the heterogeneity observed. The greatest benefit of SC transplantation was seen in patients aged ≥18 years or a medical history of <3 months. In addition, the SC injection dose of ≥107 IU/kg/day was more effective than <107 IU/kg/day when the cellular composition included mesenchymal SCs and hematopoietic SCs. In conclusion, SC therapy represents an efficient option for patients with T1DM. This systematic review was registered at the International prospective register of systematic reviews (no. 42018093930).

Redox cell signaling and hepatic progenitor cells

Hepatic diseases are widespread in the world and organ transplantation is currently the only treatment for liver failure. New cell-based approaches have been considered, since stem cells may represent a possible source to treat liver diseases. Acute and chronic liver diseases are characterized by high production of reactive oxygen and nitrogen species, with consequent oxidative modifications of cellular macromolecules and alteration of signaling pathways, metabolism and cell cycle. Although considered harmful molecules, reactive species are involved in cell growth and differentiation processes, modulating the activity of transcription factors, which take part in stemness/proliferation. It is conceivable that redox balance may regulate the development of hepatic progenitor cells, function and survival in synchrony with metabolism during chronic liver diseases. This review aims to summarize diverse redox-sensitive signaling pathways involved in stem cell fate, highlighting the important role of hepatic progenitor cells as a possible source to treat end-stage liver disease for organ regeneration.

Efficacy and safety of autologous stem cell transplantation for decompensated liver cirrhosis: A retrospective cohort study

AIM

To evaluate the long-term efficacy and safety of autologous stem cell transplantation (SCT) for decompensated liver cirrhosis.

METHODS

Consecutive patients with decompensated liver cirrhosis were included and assigned into the SCT group and non-transplantation (non-SCT) group according to whether they received SCT treatment. Patients were followed up for ten years. The long-term survival rate and incidence of hepatocellular carcinoma (HCC) were compared between groups.

RESULTS

A total of 159 patients were enrolled, including 27 cases in the SCT group and 132 cases in the non-SCT group. The baseline characteristics were significantly different between the two groups. Propensity score matching (PSM) was used to match SCT and non-SCT patients. After PSM, 92 subjects were enrolled in the final analysis, including 23 cases in the SCT group and 69 cases in the non-SCT group. The overall mortality was 73.9% and 55.1%, and the median survival period was 48 and 64 mo, respectively. However, no significant difference was found in the long-term survival rate between the two groups (P > 0.05). In addition, the incidence of HCC was higher in the SCT group than in the non-SCT group (47.8% vs 21.7%, P < 0.05). After adjusting for other covariates, SCT (OR = 3.065, 95%CI: 1.378-6.814) and age (OR = 1.061, 95%CI: 1.021-1.102) were independently correlated with the development of HCC in this decompensated liver cirrhosis cohort.

CONCLUSION

Autologous SCT may fail to improve the long-term efficacy and increase the incidence of HCC for decompensated liver cirrhosis. Close monitoring of HCC is strongly recommended in patients undergoing autologous SCT.

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.

Cholangiocytes: Cell transplantation

BACKGROUND

Due to significant limitations to the access to orthotropic liver transplantation, cell therapies for liver diseases have gained large interest worldwide.

SCOPE OF REVIEW

To revise current literature dealing with cell therapy for liver diseases. We discussed the advantages and pitfalls of the different cell sources tested so far in clinical trials and the rationale underlying the potential benefits of transplantation of human biliary tree stem cells (hBTSCs).

MAJOR CONCLUSIONS

Transplantation of adult hepatocytes showed transient benefits but requires immune-suppression that is a major pitfall in patients with advanced liver diseases. Mesenchymal stem cells and hematopoietic stem cells transplanted into patients with liver diseases are not able to replace resident hepatocytes but rather they target autoimmune or inflammatory processes into the liver. Stem cells isolated from fetal or adult liver have been recently proposed as alternative cell sources for advanced liver cirrhosis and metabolic liver disease. We demonstrated the presence of multipotent cells expressing a variety of endodermal stem cell markers in (peri)-biliary glands of bile ducts in fetal or adult human tissues, and in crypts of gallbladder epithelium. In the first cirrhotic patients treated in our center with biliary tree stem cell therapy, we registered no adverse event but significant benefits.

GENERAL SIGNIFICANCE

The biliary tree stem cell could represent the ideal cell source for the cell therapy of liver diseases. This article is part of a Special Issue entitled: Cholangiocytes in Health and Diseaseedited by Jesus Banales, Marco Marzioni, Nicholas LaRusso and Peter Jansen.

A pooled analysis of mesenchymal stem cell-based therapy for liver disease

BACKGROUND

Liver disease is a major cause of death and disability. Mesenchymal stem cells (MSCs) show promise for the treatment of liver disease. However, whether MSC-based therapy is more effective than conventional treatment is unclear, as are the optimal MSC source, the administration frequency, and the most effective MSC delivery route. We therefore undertook a systematic review and meta-analysis of the therapeutic efficacy of MSCs against liver disease and the related factors.

METHODS

We systematically searched Medline (PubMed), Cochrane Library, EMBASE, ClinicalTrials.gov, and SinoMed CBM to identify studies published up to June 2017 involving liver disease patients receiving MSC-based therapy and which reported estimates of liver function during the follow-up period.

RESULTS

Thirty-nine studies were selected from 672 publications. According to a meta-analysis of 23 controlled studies, compared with conventional treatment MSC therapy significantly improves liver function in patients with liver disease in terms of the model of end-stage liver disease score, albumin, alanine aminotransferase, and total bilirubin levels, and prothrombin time, up to 6 months after administration. However, it has no beneficial effects in terms of prothrombin activity, international normalized ratio, or cholinesterase level. Considerable heterogeneity was identified at most time points. Subgroup analyses showed that a single MSC injection was more effective than multiple injections, MSC administration was more effective via the hepatic artery than the peripheral vein, and MSCs derived from bone marrow were more effective than those derived from the umbilical cord.

CONCLUSIONS

MSC-based therapy is relatively safe and improves liver function during the first 6 months after administration. A single injection administration via the hepatic artery and MSCs derived from bone marrow are optimal in terms of improving liver function. However the significant heterogeneity among studies and discontinuous results of the subgroup meta-analysis should be addressed; moreover the long-term efficacy of MSC therapy warrants further investigation.

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.

Current Perspectives Regarding Stem Cell-Based Therapy for Liver Cirrhosis

Liver cirrhosis is a major cause of mortality and a common end of various progressive liver diseases. Since the effective treatment is currently limited to liver transplantation, stem cell-based therapy as an alternative has attracted interest due to promising results from preclinical and clinical studies. However, there is still much to be understood regarding the precise mechanisms of action. A number of stem cells from different origins have been employed for hepatic regeneration with different degrees of success. The present review presents a synopsis of stem cell research for the treatment of patients with liver cirrhosis according to the stem cell type. Clinical trials to date are summarized briefly. Finally, issues to be resolved and future perspectives are discussed with regard to clinical applications.

Emerging advancements in liver regeneration and organogenesis as tools for liver replacement

PURPOSE OF REVIEW

Although the liver possesses a unique, innate ability to regenerate through mass compensation, transplantation remains the only therapy when damage outpaces regeneration, or liver metabolic capacity is irreversibly impacted. Recent insight from developmental biology has greatly influenced the advancement of alternative options to transplantation in these settings.

RECENT FINDINGS

Factors known to direct liver cell specification, expansion, and differentiation have been used to generate hepatocyte-like cells from stem and somatic cells for developing cell therapies. Additionally, interactions between hepatic epithelial and nonepithelial cells key to establishing hepatic architecture have been used in tissue engineering approaches to advance self-organizing hepatic organoids and bioartificial liver devices. Simultaneously, recent clinically applicable advances in human hepatocyte transplantation and promotion of innate hepatic regeneration have been limited.

SUMMARY

Although mature hepatocytes have the potential to bridge to, or replace whole organ transplantation, limits in the ability to obtain healthy cells, stabilize in-vitro expansion, cryopreserve, and alleviate rejection, still exist. Alternative sources for generating hepatocytes hold promise for cell therapy and tissue engineering. These may allow generation of autologous or universal donor cells that eliminate the need for immunosuppression; however, limits exist regarding hepatocyte maturity and efficacy at liver repopulation, as well as applicability to human chronic liver disease.

Ultrasound-guided percutaneous portal transplantation of peripheral blood monocytes in patients with liver cirrhosis

BACKGROUND/AIMS

Liver transplantation offers the only definite cure for cirrhosis but lacking donors is problem. Stem cell therapy is attractive in this setting. In this study, we aimed to explore the safety and efficacy of ultrasound-guided percutaneous portal transplantation of peripheral blood monocyte cell (PBMC) in cirrhotic patients.

METHODS

A total of nine decompensated cirrhotic patients were randomized into three groups: group 1 (n = 3) was control group, group 2 (n = 3) received granulocyte-colony stimulating factor (G-CSF) mobilization for 3 days, and group 3 (n = 3) received G-CSF mobilized PBMCs by leukapheresis and PBMC transplantation through ultrasound-guided percutaneous portal vein puncture. Liver function and clinical features were evaluated.

RESULTS

At baseline, the Child-Turcotte-Pugh and the model for end-stage liver disease scores were comparable in study groups. Compared with group 1, there was a tendency to improve liver function in group 3 at 6 months after treatment. Treatment was tolerable and no complications were encountered related to the G-CSF mobilization or percutaneous portal administration of PBMCs. Imaging studies showed patent portal veins at the end of the study period.

CONCLUSIONS

Autologous PBMC transplantation through ultrasound-guided percutaneous portal vein puncture could be considered as a safe alternative treatment for decompensated cirrhotic patients.

Commercial Production of Autologous Stem Cells and Their Therapeutic Potential for Liver Cirrhosis

Human adipose-derived stem cells (hADSCs) are a promising source of autologous stem cells for personalized cell-based therapies. Culture expansion of ADSCs provides an attractive opportunity for liver cirrhosis patients. However, safety and stability issues can pose big challenges for personalized autologous stem cell products. In the present study, we addressed whether the commercial production program could provide a consistent product for liver cirrhosis therapy. We collected adipose tissue from three human donors by lipoaspirate and isolated ADSCs, which were expanded in culture to reach 1 × 108 cells (an approximately 1,000-fold expansion) within four passages. We then examined their morphology, chromosome stability, surface markers, and differentiation ability after culture. Next, we explored their therapeutic potential using a rat model of thioacetamide-induced liver cirrhosis. Culture-expanded ADSCs were injected intrahepatically, and their biodistribution was tracked by immunohistochemistry using an antibody against human mitochondria. Finally, we tested for tumor development by subcutaneously injecting a 100-fold dose range of cultured ADSCs into immunocompromised mice. Taken together, we find that culture expansion of autologous ADSCs is a potentially suitable stem cell product for personalized cell-based therapy for patients with liver cirrhosis.

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

BACKGROUND

Chronic liver disease (CLD) is a major health burden worldwide. Liver cirrhosis, a form of CLD is the fifth most common cause of death in the UK. Acute-on-chronic liver failure (ACLF) is the result of an acute insult superimposed on patients with liver cirrhosis as a result of precipitating events such as infection or bleeding. ACLF has a high associated mortality as a result of multi-organ failure. The only effective treatment for CLD is liver transplantation, but the treatment is limited by shortage of donor organs. As a result, alternative treatments such as cell therapies have been studied in patients with liver diseases. This study will systematically review the evidence on clinical effectiveness of cell therapies in patients.

METHODS

All types of study design that investigate the effectiveness of cell therapies (haematopoietic, mesenchymal and unsorted cell types) of autologous or allogeneic origin and/or the use of granulocyte colony-stimulating factor in patients with CLD including ACLF will be included (except case reports). Both autologous and allogenic cell types will be included. The primary outcomes of interest are survival, model for end-stage liver disease score, quality of life and adverse events. Secondary outcomes include liver function tests, Child-Pugh score and events of liver decompensation. A literature search will be conducted in the following databases: MEDLINE, MEDLINE in Process, EMBASE and Cochrane Library (CENTRAL, CDSR, DARE, HTA databases). Trial registers will be searched for ongoing trials, as will conference proceedings. Reference lists of relevant articles and systematic reviews will be screened. Randomised controlled trial (RCT) evidence is likely to be scant; therefore, controlled trials and concurrently controlled observational studies will be primarily analysed and uncontrolled observational studies will be analysed where primary outcomes are not reported in the control studies or where uncontrolled studies have longer follow-up. Initial screening of studies will be carried by one reviewer with a proportion checked by another reviewer. Full-text selection will be performed by two reviewers independently against the pre-defined selection criteria. The data collection and the risk of bias assessment will be completed by one reviewer and counter checked by another reviewer for all selected studies. Where appropriate, data will be meta-analysed for each study design, therapy and outcome. Data specifically on ACLF will be treated as a subgroup.

DISCUSSION

This systematic review will identify the available evidence on the effectiveness of cell therapies in patients with CLD and in ACLF subgroup. The findings will aid decision-making by clinicians and health service leaders.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42016016104.