Security and Efficacy of Intra-Portal Infusion of Autologous Stem Cells for Liver Regeneration a Randomized Pilot Study

Research Article

J Stem Cell Res Transplant. 2015; 2(2): 1018.

Security and Efficacy of Intra-Portal Infusion of Autologous Stem Cells for Liver Regeneration a Randomized Pilot Study

José-María Álamo¹*, Lydia Barrera², Magdalena Carmona¹, Javier Peiró4, Gonzalo Suárez¹, Luis- Migue¹ Marín¹, Carmen Bernal¹, Juan Serrano¹, Concepción Herrera5, Jordi Muntané², MiguelÁnge¹ Gómez¹ and Javier Padillo¹

¹Department of Hepatobiliary Surgery, Virgen del Rocío Hospital, University of Seville, Spain

²Department of Hematology, Biomedicine Institute of Sevilla, University of Seville, Spain

³Department of Hematology, Virgen del Rocío Hospital, University of Seville, Spain

4Department of Interventional Radiology, Virgen del Rocío Hospital, University of Seville, Spain

5Department of Hematology, Reina Sofía Hospital, University of Cordova, Spain

*Corresponding author: José-María Álamo, Department of Hepatobiliary Surgery, Virgen del Rocío Hospital, University of Seville, Spain

Received: January 25, 2015; Accepted: September 14, 2015; Published: October 03, 2015


Aim: To analyze security of intraportal infusion of autologous stem cells during portal embolization to increase remanent liver volume.

Methods: Phase II clinical trial studying intraportal infusion of autologous stem cells processed from patient bone marrow. Stem cells are applicated during preoperatoy portal embolization used to increase the volume of remanent liver in patient’s subsidiary of major hepatectomy.

Results: 12 patients, of which 5 have undergone PE and intraportal infusion of SC: liver metastasis of colorectal carcinoma 40% / 42.8%, hepatocellular carcinoma 40% / cholangiocarcinoma 28.6% and 20% / 28.6%. Average bone marrow extracted in SC-group patients was 270 cc, having infused a mean of 36 cc of intraportal SC. Not fever cases, not portal vein thrombosis liver abscess or tumor disease progression were detected. Biopsies token during hepatectomy did not show fibrosis or hepatic steatosis different from ablated tissue. Differences in the increase of the volume of the remnant liver were not statistically significant.

Conclusion: The intraportal infusion of autologous stem cells, extracted and processed from the patient’s own bone marrow, using the procedure portal embolization for intrahepatic infusion, appears to be a safe method.

Keywords: Stem cells; Portal embolization; Liver resection


To date management of patients with liver tumors which required extended hepatectomy is performed by performing preoperative embolization segments in which the lesion is located, to facilitate regeneration of the remaining segments, which allows performing safer surgery. However, the response to the contra lateral embolization site is slow and often has an excessive time to tumor growth that occurs, thus precluding sometimes curative treatment. Recently, the treatment being investigated by implantation of adult progenitor cells derived from the bone marrow into the portal vein of the remaining segments with promising results cells. The application of adult stem cells in hepatic regeneration treatment is included as part of the regenerative medicine and is an advanced technique in this field.

Liver regeneration

At present it is considered that liver regeneration is a process that takes place in several phases, of which two are critical: a] the transition from quiescent hepatocytes [at rest] to enter the cell cycle and b] their progression through the G1 phase of the cell cycle. These steps are critical to the hepatocyte, as are the bridges between a proliferative and an apoptotic process [1-3].

Capacity of hepatocyte regeneration

After performing a partial hepatectomy (70%], liver regenerates once or twice by dividing hepatocytes to complete this process and return to their quiescent state [4]. Hepatocyte replication does not exceed more than two cycles; nevertheless retained their proliferative capacity. It has observed after regain its lost ground, if a new segment of the liver is removed; restart the hepatocyte cell cycle and doubles [2-4]. The ability of multiplication has clearly been demonstrated in transgenic mice deficient in grow factors. These animals are born with a genetic defect that prevents them from having a healthy adult liver, so they die early. These animals were transplanted hepatocytes proliferate healthy animals to restore proper mass and liver function. When liver recover their function, are used as donors to other transgenic animals and recovering the latter, like the first, the function of the transplanted hepatocytes. Such transplants have been tested up to eight rounds; in each case, the transplanted animals recover their function without apparent mass and decrease in proliferative capacity of hepatocytes [5-8]. It has also been found that in serial transplantation, where using the same parent cell line, cell populations 7 x 1020 more times than the original population (greater than the proliferative capacity of hematopoietic tissue Index) [5-8] is doubled.

The hepatocyte proliferative capacity is not associated to the size, location within the hepatic lobule or number of cores it has. Neither is associated with the proliferative capacity and age of the donor, as both young adults and the elderly have the same proliferative capacity of their hepatocyte. Such studies have indicated that the hepatocytes in normal state, have suppressed their proliferative capacity and that the agency maintains the regulation of cell proliferation to express at the right time [5-8].

Precursor cells in the liver

The proliferative capacity of adult hepatocytes explains the coexistence within the liver, precursor cells or stem cell [stem cell]. Found ductal liver epithelial cells and cells with ability to differentiate into hepatocytes, bile ducts [channels Herring]. These are a “cellular reservoir” in the adult liver, as they are able to differentiate into mature hepatocytes or ductal cells after acute intoxication, massive necrosis or any other damage to liver tissue. When liver damage occurs by any of these causes, the ductal cells are transformed into a specific type of indifferenciate cells, called “oval cells”, which are grouped into “clusters” to form an “oval box” where performs the cell proliferation. If research demonstrating lack oval cells are the original progenitor maintained in steady state in the liver or constitutes the first pluripotential precursor previous to primitive cell [9-15].

The transcription factor NFkB [Nuclear Factor κ Chain in B Lymphocytes] and STAT3 are two of the major proteins that are activated at the start of liver regeneration. These do not require prior synthesis protein, since only depend on post-transcription mechanism activated [16-22]. The transcription factor STAT3 is activated more slowly than the NFkB and activation mechanism is completely different. After partial hepatectomy, STAT3 is activated in the first two hours and stays active for four to six. STAT3 is a member transcription factors known as “signal transducers and activators of transcription” [Signal Transduction and Activators of Transcription]. So far, seven members of this family, of which the best known STAT3 is known. Its activation by cytokines, such as interLeukin-6 [IL-6],using a specific receptor for the translation of intracellular signals [22-24]. This receptor binds two important growth factors for the liver, such as TGFa and Hepatocyte Growth Factor [HGF], so that they stimulate regeneration and healing of the liver. The activation and inhibition of gene expression is a complex process during the early stages of liver regeneration. It is important to know how to start the regenerative process and activation and inhibition of transcription factors regulate and maintain the initial activation process early genes, in addition to understanding their participation in each phase of the regeneration cycle. It is accepted that growth factors and cytokines are first molecular elements to initiate and to mark the hepatocyte proliferation. The main growth factors, identified as initiators of the regenerative process, comprising at TGFa, HGF, EGF and IL-6. These have been shown, separately or in combination, lead to a hepatocyte of the G0 state [quiescent state] to G1 [initial active state] of the cell cycle. Growth factors released in the initial process of hepatic regeneration, activated transcription factors early genes and for the cell through the quiescent cells to the G1 phase of the cell cycle. In addition, these factors promote cell progression through G1 phase and whether favorable conditions, passing the “critical control points” to duplicate its genetic material into the S phase of the cycle. Once the cell passes through the “hot spots” of the G1 phase, takes the total cell cycle into a “domino effect” where one active to another system to complete all phases of the cell cycle [25-28].

Portal embolization

Preoperative Portal Embolization [PE] emerged from the need to increase the number of candidates for surgery, especially in those patients in whom the future liver remnant would not ensure hepatocellular function. In the 1980s, in Japan, several studies led to the development of the PE; firstly, it began to be embolized, during surgery branches afferent hepatocarcinomas portals to avoid dissemination to healthy transportal territory. In the pre-intervention or in patients who, for various reasons, could not be operated period, a marked hypertrophy not embolized tissue was observed. It is also that in patients with liver tumors [cholangiocarcinoma type] with a progressive infiltration of portal vein, an increase in volume of sound produced known territory. These observations led to Makuuchi et al. Practice PE for growth the liver would not be resected.

Since then, many series, articles, papers and reviews presented in the literature on PE, and still remains controversy over the technical approach, the ideal embolization material, or on the indications and contraindications. The fundamental goal of PE is to induce hepatic atrophy tumor area with remnant liver hypertrophy. The aim is to increase the number of candidates for surgery, offering survival rates similar to those of patient groups in the preoperative staging was more favorable.

In addition, improving the hepatic functional reserve will be sought to decrease the possibility of encountering postoperative complications related mainly to liver failure. For reasons not yet well known, after hepatic aggression [partial surgical resection, portal vein occlusion] cellular mechanisms of liver regeneration are triggered. The hepatocyte has a great capacity for dedifferentiation [hepatocyte appearance of ‘fetal type’] and clonal expansion. The primary responsibility of this role will be the hepatocyte growth factor [Hepatic Growth Factor [HGF]], other factors such as intrahepatic release Tissue Necrotic Factor [TNF], or extrahepatic release, such as insulin, act as comitogénicos with HGF. Another point to consider is that the embolized territory no cell necrosis will occur, therefore, no cytolysis [increased transaminases, pain, fever, etc.] but apoptosis, why is minimal postembolization syndrome after PE [29]. Remains debate over whether the embolic agent, whose choice will be discussed below, should produce periportal inflammation or no inflammation and that this, in addition to conditioning surgery may trigger mechanisms cellular necrosis [30].

Stem cells in liver regeneration

Hematopoietic Stem Cells [SC] derived from bone marrow are the most studied [31], especially since its discovery in the sixties as basic cells in the bone marrow hematopoiesis. Besides from bone marrow, the SC can also be obtained from peripheral blood and cord blood. The ease of obtaining these cells make them ideal for cellular therapies. Concerning liver regeneration, it has been found in several studies that the SC is able to activate the “hepatocyte-like cells” and repopulate the liver of mice by changing their phenotype [31-35]. The numerous studies published, it appears that the effectiveness of the isolated umbilical cord SC is greater than those obtained from peripheral blood or bone marrow. The mechanism by which the SC generates mature hepatocytes is still unknown. In some animal models occurs after the merger of these SC with host liver hepatocytes [36-39], although other studies SCs to differentiate into mature hepatocytes [40]. It is possible that the population of SC stimulate production of hepatocytes [41-43]. SC is not all equally effective. As previously noted, the isolated peripheral blood are less effective. By contrast, the phenotype Lin-CD38 + BMCD34 seems to be the most stimulating liver regeneration [44, 45].