Feasibility and safety of G-CSF administration to induce bone marrow-derived cells mobilization in patients with end stage liver disease

Infusion of autologous bone marrow mononuclear cells through hepatic artery results in a short-term improvement of liver function in patients with chronic liver disease: a pilot randomized controlled study

AIM

This randomized controlled study evaluated the effect of autologous infusion of bone marrow cells (BMC) in patients with hepatic cirrhosis.

METHODS

Thirty patients on the liver transplant waiting list were randomly assigned to receive BMC therapy or no treatment. They were followed up for 1 year. The study was nonblinded. Autologous mononuclear-enriched BMC were infused into the hepatic artery; liver function scores/tests were chosen as endpoints to assess efficacy. Statistical analysis calculated mean relative changes (RC) from baseline and fitted a random-effects model.

RESULTS

Mean age, baseline model for end-stage liver disease, and Child-Pugh score were similar in both groups. Child-Pugh score improved in the first 90 days in the cell therapy group compared with controls (P = 0.017, BMC group RC = -8%, controls RC = +5%). The model for end-stage liver disease score remained stable in the treated patients (RC -2 to +6%), whereas it increased during follow-up in the control group (RC +6 to +18%). Albumin levels improved in the treatment arm, whereas they remained stable among controls in the first 90 days (P = 0.034; BMC group RC = +16%, control group RC = +2%). Bilirubin levels increased among controls, whereas they decreased in the therapy arm during the first 60 days; INR RC differences between groups reached up to 10%. The changes observed did not persist beyond 90 days.

CONCLUSION

Transplantation of autologous BMC into the hepatic artery improved liver function in patients with advanced cirrhosis in the first 90 days. However, larger studies are necessary to define the role of BMC therapy in cirrhotic patients. Repeated autologous BMC infusions or combination therapy with granulocyte-colony-stimulating factor might improve or sustain the treatment response.

Improvement of liver function in liver cirrhosis patients after autologous mesenchymal stem cell injection: a phase I-II clinical trial

BACKGROUND

End-stage liver disease is a medical problem with high morbidity and mortality. We have investigated the feasibility, safety, and efficacy of using autologous mesenchymal stem cells (MSCs) as a treatment.

METHODS

Eight patients (four hepatitis B, one hepatitis C, one alcoholic, and two cryptogenic) with end-stage liver disease having Model for End-Stage Liver Disease score > or =10 were included. Autologous MSCs were taken from iliac crest. Approximately, 30-50 million MSCs were proliferated and injected into peripheral or the portal vein. Liver function and clinical features were evaluated at baseline and 1, 2, 4, 8, and 24 weeks after injection.

RESULTS

Treatment was well tolerated by all patients. Liver function improved as verified by the Model for End-Stage Liver Disease score, which decreased from 17.9+/-5.6 to 10.7+/-6.3 (P<0.05) and prothrombin complex from international normalized ratio 1.9+/-0.4 to 1.4+/-0.5 (P<0.05). Serum creatinine decreased from 114+/-35 to 80+/-18 micromol/l (P<0.05). Serum albumin changed from 30+/-5 to 33+/-5 g/l and bilirubin from 46+/-29 to 41+/-31 micromol/l. No adverse effects were noted.

CONCLUSION

Our data show that MSCs injection can be used for the treatment of end-stage liver disease with satisfactory tolerability. Furthermore, this treatment may improve clinical indices of liver function in end-stage liver disease.

Human hepatocyte transplantation: state of the art

Hepatocyte transplantation is making its transition from bench to bedside for liver-based metabolic disorders and acute liver failure. Over eighty patients have now been transplanted world wide and the safety of the procedure together with medium-term success has been established. A major limiting factor in the field is the availability of good quality cells as hepatocytes are derived from grafts that are deemed unsuitable for transplantation. Alternative sources of cell, including stem cells may provide a sustainable equivalent to primary hepatocytes. There is also a need to develop techniques that will improve the engraftment, survival and function of transplanted hepatocytes. Such developments may allow hepatocyte transplantation to become an accepted and practical alternative to liver transplantation in the near future.

Current status of stem cell therapy for liver diseases

Liver failure is one of the main causes of death worldwide and is a growing health problem. Since the discovery of stem cell populations capable of differentiating into specialized cell types, including hepatocytes, the possibility of their utilization in the regeneration of the damaged liver has been a focus of intense investigation. A variety of cell types were tested both in vitro and in vivo, but the definition of a more suitable cell preparation for therapeutic use in each type of liver lesions is yet to be determined. Here we review the protocols described for differentiation of stem cells into hepatocytes, the results of cell therapy in animal models of liver diseases, as well as the available data of the clinical trials in patients with advanced chronic liver disease.

Stem/progenitor cells in liver injury repair and regeneration

Morbidity and mortality from cirrhosis is increasing rapidly in the world. Currently, orthotopic liver transplantation is the only definitive therapeutic option. However, its clinical use is limited, because of poor long-term graft survival, donor organ shortage and high costs associated with the procedure. Stem cell replacement strategies are therefore being investigated as an attractive alternative approach to liver repair and regeneration. In this review we discuss recent preclinical and clinical investigations that explore the therapeutic potential of stem cells in repair of liver injuries. Several types of stem cells. including embryonic stem cells, haematopoietic stem cells and mesenchymal stem cells, can be induced to differentiate into hepatocyte-like cells by defined culture conditions in vitro. Stem cell transplantation has been shown to significantly improve liver function and increase animal survival in experimentally-induced liver-injury models. Moreover, several pilot clinical studies have reported encouraging therapeutic effects in patients treated with stem cells. Although there remain many unresolved issues, the available data support the notion that stem cell technology may lead to the development of effective clinical modalities for human liver diseases.

[Clinical application of stem cells in liver diseases]

Most liver diseases lead to hepatic dysfunction with organ failure. Liver transplantation is the best curative therapy, but it has some limitations such as donor shortage, possibility of rejection, and maintenance of immunosuppressant. New therapies have been actively searched for over several decades, primarily in the form of artificial liver support devices and hepatocyte transplantation, but both of these modalities remain experimental. Stem cells have recently shown promise in cell therapy because they have the capacity for self-renewal and multilineage differentiation, and are applicable to human diseases. Very recent reports of unexpected plasticity in adult bone marrow have raised hopes of stem cell therapy offering exciting therapeutic possibilities for patients with chronic liver disease. Both rodent and human embryonic stem cells, bone marrow hematopoietic stem cells, mesenchymal stem cells, umbilical cord blood cells, fetal liver progenitor cells, adult liver progenitor cells, and mature hepatocytes have been reported to be capable of self-renewal, giving rise to daughter hepatocytes both in vivo and in vitro. These cells can repopulate livers in animal models of liver injury and appear to be able to improve liver function. However, significant challenges still exist before these cells can be used in humans, such as the lack of consensus about the immunophenotype of liver progenitor cells, uncertainty of the physiological role of reported candidate stem/progenitor cells, practicality of obtaining sufficient quantity of cells for clinical use, and concerns over ethics, long-term efficacy, and safety. There have been reports of phase 1 trials using stem cell transplantation in humans for liver diseases, but more effective trials are needed. We review the use of stem cells (focusing on adult ones) and the reported human clinical trials, and highlight the challenges facing clinicians in their quest to use liver stem cells to save lives.

Controlled trials in hepatitis B virus-related decompensate liver cirrhosis: peripheral blood monocyte transplant versus granulocyte-colony-stimulating factor mobilization therapy

BACKGROUND

Liver cirrhosis represents the end stage of chronic liver injury. Currently, liver transplantation provides the only definite cure but it is beset with many problems, including lack of donors and risk of rejection. Stem cell therapy is very attractive in this setting because it has the potential to help tissue regeneration. In this study, we aimed to investigate the therapeutic effect of peripheral blood monocyte cell (PBMC) transplantation in decompensated liver cirrhosis.

METHODS

A total of 40 subjects (31 men and nine females, age range 21-71 years) was recruited to two groups. Group 1 received granulocyte-colony-stimulating factor (G-CSF) mobilization, PBMC collection by leukapheresis and PBMC transplant therapy. Group 2 received G-CSF mobilization for 4 days. At baseline and 6 months after treatment, liver function of the two groups was monitored by blood examination and ultrasonagraphy.

RESULTS

Both groups gained significant improvement in liver synthetic function, such as serum albumin and prothrombin time, from baseline to 6 months after treatment (P<0.01). However, there was no significant difference in alanine aminotransferase, aspartate aminotransferase and total bilirubin in both groups (P>0.05). Compared with group 2, a significantly improved liver function was observed in group 1, including elevated serum albumin level and a decreased CTP score (P<0.05). No major adverse effects were noted.

DISCUSSION

Autologous PBMC transplantation could be considered as a novel and alternative treatment for patients with decompensated liver cirrhosis.

Autologous bone marrow cell infusion therapy for liver cirrhosis

The plasticity of bone marrow cells (BMC) has been confirmed by autopsy results of female recipients of BMC from male donors. To establish new clinical therapies for patients with liver cirrhosis using autologous BMC, we developed a new in vivo murine model using green fluorescent protein (GFP) and repeated carbon tetrachloride (CCl(4)) injection. We found that BMC infused through the tail vein, efficiently repopulated cirrhotic liver tissue and, under the influence of persistent liver damage induced by carbon tetrachloride, differentiated into albumin-producing hepatocytes. Moreover, such BMC infusions into mice with cirrhosis improved liver function and reduced mortality. The latter observation correlated with the strong expression of matrix metalloproteinases (MMP), particularly MMP-9, and reduced hepatic fibrosis. The results from the 'GFP/CCl(4) model' showed that cell therapy using autologous BMC has the potential to become an effective treatment for patients with liver failure due to advanced liver cirrhosis. This review summarizes previous findings plus these recent experimental results, as well as recent clinical trials of BMC transfusion into patients with end-stage chronic liver disease.

Critical review of clinical trials of bone marrow stem cells in liver disease

Morbidity and mortality from cirrhosis is increasing rapidly in the Western world. Currently the only effective treatment is liver transplantation, an increasingly limited and expensive resource. Consequently, there has been great hope that stem cells may offer new therapeutic approaches in the management of liver disease. In this review we critically appraise the 11 published clinical studies of bone marrow stem cells in liver disease, and focus on the unresolved issues regarding their role. We outline the different mechanisms by which stem cells may impact on liver disease, as well as highlight the importance of the type of stem cell chosen. There are multiple different stem cell populations that have, in rodent studies, been shown to have differing effects on liver regeneration and fibrogenesis/degradation. Thus, choice of cell should reflect the desired or expected mechanism of action. The importance, and methods, of studying the fate of stem cells infused in clinical studies is emphasized as we seek to translate observations in rodents into the clinical setting. Finally, we discuss which cohorts of patients with liver disease would benefit from stem cell therapy, as well as establish minimum criteria for future clinical trials of stem cells.

Stem cells, a two-edged sword: Risks and potentials of regenerative medicine

The recent advancements in stem cell (SC) biology have led to the concept of regenerative medicine, which is based on the potential of SC for therapies aimed to facilitate the repair of degenerating or injured tissues. Nonetheless, prior to large scale clinical applications, critical aspects need to be further addressed, including the long-term safety, tolerability, and efficacy of SC-based treatments. Most problematic among the risks of SC-based therapies, in addition to the possible rejection or loss of function of the infused cells, is their potential neoplastic transformation. Indeed, SCs may be used to cure devastating diseases, but their specific properties of self-renewal and clonogenicity may render them prone to generate cancers. In this respect, ‘Stemness’ might be seen as a two-edged sword, its bright side being represented by normal SCs, its dark side by cancer SCs. A better understanding of SC biology will help fulfill the promise of regenerative medicine aimed at curing human pathologies and fighting cancer from its roots.

Granulocyte-colony stimulating factor induces proliferation of hepatic progenitors in alcoholic steatohepatitis: a randomized trial

Liver failure is the major cause of death in alcoholic steatohepatitis (ASH). In experimental hepatitis, granulocyte-colony stimulating factor (G-CSF) mobilizes hematopoietic stem cells, induces liver regeneration, and improves survival. We studied the short-term effects of G-CSF on CD34+ stem cell mobilization, liver cell proliferation, and liver function in patients with ASH. Twenty-four patients (mean age 54 years) with alcoholic cirrhosis [Child-Turcotte-Pugh score 10 (7-12)] and concomitant biopsy-proven ASH [Maddrey score 36 (21-60)] were randomized to standard care associated with 5 days of G-CSF (10 microg/kg/day, group A, n = 13) or standard care alone (group B, n = 11). Serial measurement of CD34+ cells, liver tests, cytokines [hepatocyte growth factor (HGF); tumor necrosis factor alpha; tumor necrosis factor-R1; interleukin-6; alfa-fetoprotein], and (13)C-aminopyrine breath tests were performed. Proliferating hepatic progenitor cells [HPC; double immunostaining (Ki67/cytokeratin 7)], histology, and neutrophils were assessed on baseline and day 7 biopsies. Abstinent alcoholic patients with cirrhosis served as controls for immunohistochemistry. G-CSF was well tolerated. At day 7, both CD34+ cells (+747% versus -6%, P < 0.003), and HGF (+212% versus -7%, P < 0.03) increased in group A but not in group B. Cytokines and aminopyrine breath test changes were similar between groups. On repeat biopsy, a >50% increase in proliferating HPC was more frequent in group A than in group B (11 versus 2, P < 0.003). Changes in Ki67+/cytokeratin 7+ cells correlated with changes in CD34+ cells (r = 0.65, P < 0.03). Neutrophils and histological changes were similar in both groups.

CONCLUSION

G-CSF mobilizes CD34+ cells, increases HGF, and induces HPC to proliferate within 7 days of administration. Larger trials would be required to determine whether these changes translate into improved liver function.

Stem cell-based therapy in gastroenterology and hepatology

Protagonists of a new scientific era, stem cells are promising tools on which regenerative medicine relies for the treatment of human pathologies. Stem cells can be obtained from various sources, including embryos, fetal tissues, umbilical cord blood, and also terminally differentiated organs. Once forced to expand and differentiate into functional progenies, stem cells may become suitable for cell replacement and tissue engineering. The manipulation and/or stimulation of adult stem cells seems to be particularly promising, as it could improve the endogenous regenerative potential without risks of rejection and overcome the ethical and political issues related to embryonic stem cell research. Stem cells are already leaving the bench and reaching the bedside, despite an incomplete knowledge of the genetic control program driving their fate and plasticity. In gastroenterology and hepatology, the first attempts to translate stem cell basic research into novel therapeutic strategies have been made for the treatment of several disorders, such as inflammatory bowel diseases, diabetes mellitus, celiachy and acute or chronic hepatopaties. Nonetheless, critical aspects need to be further addressed, including the long-term safety, tolerability and efficacy of cell-based treatments, as well as their carcinogenic potential. Aim of this review is to summarize the state-of-the-arts on gastrointestinal and hepatic stem cells and on stem cell-based therapies in gastroenterology and hepatology, highlighting both the benefits and the potential risks of these new tools for the treatment and prevention of human diseases.

Stem cell mobilization and collection in patients with liver cirrhosis

BACKGROUND

Bone marrow-derived stem cells (BMSC) and granulocyte colony-stimulating factor (G-CSF) have been proved to contribute to tissue regeneration after liver injury.

AIMS

To test the safety of G-CSF and define the exact dose capable of mobilizing BMSC in the majority of patients with liver cirrhosis; and to assess the feasibility of leukapheresis to collect BMSC from peripheral blood.

METHODS

In this study, we treated 18 patients affected by liver cirrhosis with increasing doses of G-CSF to mobilize CD34(+) and CD133(+) BMSC into the peripheral blood.

RESULTS

The dose-finding phase demonstrated that 15 microg/kg/day of G-CSF is the optimal dose to mobilize both CD34(+) and CD133(+) stem cells. Circulating BMSC were collected by a single step leukapheresis in three patients and the mean number of CD34(+) and CD133(+) cells cryopreserved was 1.3 +/- 0.7 and 1.2 +/- 0.5 x 10(6)/kg, respectively. No severe adverse events were observed during the drug administration and stem cell collection. Noteworthy is, none of the patients showed a significant modification of liver function.

CONCLUSIONS

Our study demonstrates that G-CSF administration and BMSC collection from the peripheral blood is possible and safe in patients with liver cirrhosis. The optimal dose to mobilize BMSC in cirrhotics is 15 microg/kg/day. At this dose, G-CSF does not seem to modify the residual liver function in cirrhotic patients.

Activation of stem cells in hepatic diseases

The liver has enormous regenerative capacity. Following acute liver injury, hepatocyte division regenerates the parenchyma but, if this capacity is overwhelmed during massive or chronic liver injury, the intrinsic hepatic progenitor cells (HPCs) termed oval cells are activated. These HPCs are bipotential and can regenerate both biliary epithelia and hepatocytes. Multiple signalling pathways contribute to the complex mechanism controlling the behaviour of the HPCs. These signals are delivered primarily by the surrounding microenvironment. During liver disease, stem cells extrinsic to the liver are activated and bone-marrow-derived cells play a role in the generation of fibrosis during liver injury and its resolution. Here, we review our current understanding of the role of stem cells during liver disease and their mechanisms of activation.

Lasting amelioration in the clinical course of decompensated alcoholic cirrhosis with boost infusions of mobilized peripheral blood stem cells

For end-stage liver disease, liver transplantation provides the only definite cure; however, many patients die while in the waiting list for donation. Various stem cell populations have been described to contribute to liver regeneration and there is accumulating evidence for the participation of hematopoietic stem cells (HSCs) in this process. We here report two cases treated with boost infusions of autologous mobilized HSCs to regenerate cirrhotic liver. The procedure was safe and well tolerated. Both patients showed a lasting amelioration in the clinical course of the disease during the 30 months of follow-up. These results suggest that the procedure may be considered in a clinical study setting as a bridging therapy until organ transplantation becomes available or to reverse a decompensated cirrhosis to a compensated one. Additional studies in this area will be required to document efficacy and evaluate toxicity.

Safety and efficacy profile of G-CSF therapy in patients with acute on chronic liver failure

BACKGROUND/AIM

We aimed to evaluate safety and efficacy of granulocyte-colony stimulating factor treatment in patients with acute on chronic liver failure and the effect of granulocyte-colony stimulating factor on the expression level of CXCR4, vascular endothelial growth factor receptor and very late activation antigen 4.

METHODS

Twenty-four patients with acute on chronic liver failure were randomised to receive standard therapy, standard therapy+granulocyte-colony stimulating factor (5 microg/kg/day for 6 days) and standard therapy+granulocyte-colony stimulating factor (15 microg/kg/day s.c. for 6 days). Data on CD34+cell mobilisation were compared to age-matched peripheral blood haematopoietic stem cell donors treated with granulocyte-colony stimulating factor. On day third of treatment, the expression level of CXCR4, vascular endothelial growth factor receptor and very late activation antigen 4 was analysed in mobilised CD34+ cells.

RESULTS

CD34 cell count increased after the second day of granulocyte-colony stimulating factor injection in both treatment groups compared to the linear increase observed in control. After the fifth day the increase was significantly higher in healthy donors versus patients with acute on chronic liver failure. A decrease in the expression of CXCR4, very late activation antigen 4 and vascular endothelial growth factor receptor compared to premobilisation values was observed. No major side effects were observed.

CONCLUSIONS

Granulocyte-colony stimulating factor treatment is able to induce CD34 mobilisation in patients with acute on chronic liver failure. The expression pattern of CXCR4, very late activation antigen 4 and vascular endothelial growth factor receptor suggests that these molecules are involved in the granulocyte-colony stimulating factor-induced stem cell mobilisation.

Granulocyte-colony stimulating factor promotes liver repair and induces oval cell migration and proliferation in rats

BACKGROUND AND AIMS

Hepatic regeneration is a heterogeneous phenomenon involving several cell populations. Oval cells are considered liver stem cells, a portion of which derive from bone marrow (BM). Recent studies have shown that granulocyte-colony stimulating factor (G-CSF) may be effective in facilitating liver repair. However, it remains unclear if G-CSF acts by mobilizing BM cells, or if it acts locally within the liver microenvironment to facilitate the endogenous restoration program. In the present study, we assessed the involvement of G-CSF during oval cell activation.

METHODS

Dipeptidyl-peptidase-IV-deficient female rats received BM transplants from wild-type male donors. Four weeks later, rats were subjected to the 2-acetylaminofluorene/partial hepatectomy model of oval cell-mediated liver regeneration, followed by administration of either nonpegylated G-CSF or pegylated G-CSF. Control animals did not receive further treatments after surgery. The magnitude of oval cell reaction, the entity of BM contribution to liver repopulation, as well as the G-CSF/G-CSF-receptor expression levels were evaluated. In addition, in vitro proliferation and migration assays were performed on freshly isolated oval cells.

RESULTS

Oval cells were found to express G-CSF receptor and G-CSF was produced within the regenerating liver. G-CSF administration significantly increased both the magnitude of the oval cell reaction, and the contribution of BM to liver repair. Finally, G-CSF acted as a chemoattractant and a mitogen for oval cells in vitro.

CONCLUSIONS

We have shown that G-CSF facilitates hepatic regeneration by increasing the migration of BM-derived progenitors to the liver, as well as enhancing the endogenous oval cell reaction.

Phase 1 human trial of autologous bone marrow-hematopoietic stem cell transplantation in patients with decompensated cirrhosis

AIM: To evaluate safety and feasibility of autologous bone marrow-enriched CD34⁺ hematopoietic stem cell Tx through the hepatic artery in patients with decompensated cirrhosis.

METHODS: Four patients with decompensated cirrhosis were included. Approximately 200 mL of the bone marrow of the patients was aspirated, and CD34⁺ stem cells were selected. Between 3 to 10 million CD34⁺ cells were isolated. The cells were slowly infused through the hepatic artery of the patients.

RESULTS: Patient 1 showed marginal improvement in serum albumin and no significant changes in other test results. In patient 2 prothrombin time was decreased; however, her total bilirubin, serum creatinine, and Model of End-Stage Liver Disease (MELD) score worsened at the end of follow up. In patient 3 there was improvement in serum albumin, porthrombin time (PT), and MELD score. Patient 4 developed radiocontrast nephropathy after the procedure, and progressed to type 1 hepatorenal syndrome and died of liver failure a few days later. Because of the major side effects seen in the last patient, the trial was prematurely stopped.

CONCLUSION: Infusion of CD34⁺ stem cells through the hepatic artery is not safe in decompensated cirrhosis. Radiocontrast nephropathy and hepatorenal syndrome could be major side effects. However, this study does not preclude infusion of CD34⁺ stem cells through other routes.

Feasibility and safety of autologous bone marrow mononuclear cell transplantation in patients with advanced chronic liver disease

AIM: To evaluate the safety and feasibility of bone marrow cell (BMC) transplantation in patients with chronic liver disease on the waiting list for liver transplantation.

METHODS: Ten patients (eight males) with chronic liver disease were enrolled to receive infusion of autologous bone marrow-derived cells. Seven patients were classified as Child-Pugh B and three as Child-Pugh C. Baseline assessment included complete clinical and laboratory evaluation and abdominal MRI. Approximately 50 mL of bone marrow aspirate was prepared by centrifugation in a ficoll-hypaque gradient. At least of 100 millions of mononuclear-enriched BMCs were infused into the hepatic artery using the routine technique for arterial chemoembolization for liver tumors. Patients were followed up for adverse events up to 4 mo.

RESULTS: The median age of the patients was 52 years (range 24-70 years). All patients were discharged 48 h after BMC infusion. Two patients complained of mild pain at the bone marrow needle puncture site. No other complications or specific side effects related to the procedure were observed. Bilirubin levels were lower at 1 (2.19 ± 0.9) and 4 mo (2.10 ± 1.0) after cell transplantation that baseline levels (2.78 ± 1.2). Albumin levels 4 mo after BMC infusion (3.73 ± 0.5) were higher than baseline levels (3.47 ± 0.5). International normalized ratio (INR) decreased from 1.48 (SD = 0.23) to 1.43 (SD = 0.23) one month after cell transplantation.

CONCLUSION: BMC infusion into hepatic artery of patients with advanced chronic liver disease is safe and feasible. In addition, a decrease in mean serum bilirubin and INR levels and an increase in albumin levels are observed. Our data warrant further studies in order to evaluate the effect of BMC transplantation in patients with advanced chronic liver disease.