Reduced mobilisation of hematopoietic stem cells after hepatic resection for malignant liver disease

The hematopoietic stem cell number in the peripheral blood of pediatric recipients correlates with the outcome after living donor liver transplantation

It has been proposed that circulating HSCs play a role in graft survival after liver transplantation. The aim was to analyze the relationship between the number of HSCs before and after LDLT and liver function, immune biomarkers, and clinical outcomes in pediatric patients. We studied 15 pairs of adult healthy liver donors and pediatric recipients with ESLD. The CD34/CD45+ cell number was measured in the blood via flow cytometry, and plasma levels of immune biomarkers - via ELISA. CD34/CD45+ cell number in the recipients decreased within the first week after LDLT. The cell number before LDLT was negatively correlated with the plasma levels of CRP and the development of graft dysfunction in the early post-transplant period. After LDLT, the CD34/CD45+ cell number was positively correlated with the pretransplant plasma level of sCD40L, a T-cell activation marker. In adult liver donors, the cell number did not change within the first week after liver resection and was lower than in pediatric recipients. The results suggest that in pediatric recipients, the HSC number may be associated with graft function and could be regarded as a potential predictor of the clinical outcome after LDLT.

Serum levels of HGF, IL-6, and TGF-α after benign liver tumor resection

PURPOSE

Literature is void of data on the relationship between pre- and postoperative levels of hepatocyte growth factor (HGF), interleukin 6 (IL-6), and tumor growth factor α (TGF-α) after liver resection performed for particular benign liver tumors. The purpose of this study was to assess whether there is a different degree of liver regeneration through the kinetics of HGF, IL-6, and TGF-α in 2 particular types of benign liver lesions.

MATERIAL/METHODS

The study included 9 patients diagnosed with hepatic hemangioma and 13 patients with focal nodular hyperplasia (FNH) who underwent liver resection. HGF, IL-6, and TGF-α were measured using enzyme-linked immunosorbent assay (ELISA) from blood serum drawn at 6 time points during an 8-day period. Statistical analysis was based on two-factor variance analysis with replicate measurements.

RESULTS

The HGF, IL-6, and TGF-α levels in patients who underwent FNH resection were not significantly different from the levels observed in hemangioma resection patients. Significant increases in HGF, IL-6, and TGF-α concentrations were observed only during the first 24h after resection in both groups of patients.

CONCLUSIONS

Obtained results suggest that the pre- and post-operative levels of HGF, IL-6, and TGF-α do not depend on the particular type of benign tumor. After resection of FNH and hemangioma tumors, the serum levels of HGF, IL-6, and TGF-α increased at similar rates during the first 24h, followed by significant declines back to pre-operative levels.

Mechanisms of liver repair following injury

Liver injury caused by a variety of physical or chemical factors is a common disease, and severe or persistent liver injury can ultimately lead to acute liver failure. Its treatment is still a formidable challenge to clinicians. Elucidation of mechanisms underlying liver repair following injury is the cornerstone of treatment of hepatic diseases. Despite many research efforts over the past decades, the mechanisms behind liver repair following injury are still not clear. Recent studies have demonstrated that oval cells and bone marrow stem cells are involved in this complex process. A variety of cells and factors may play a role in different stages of this process. In this paper, we will review mechanisms of liver repair following injury.

Hematopoietic stem cell mobilization into the peripheral circulation in patients with chronic liver diseases

OBJECTIVE

The present study was aimed to investigate and compare the kinetics of bone marrow-derived hematopoietic stem cells (BMHSC) migration in the peripheral blood and liver in response to liver injury in patients with chronic liver disease (CLD).

METHODS

In all, 45 CLD patients staged with Child-Pugh A, B and C and 15 healthy participants were evaluated for the concentration of circulating BMHSC by a flow cytometric analysis of CD133(+) /CD34(+) cells. In addition, homing BMHSC and hepatic progenitors were assessed by the immunohistochemical detection of CD133(+) and OV6(+) cells in liver biopsy specimens from Child-Pugh A and B patients.

RESULTS

No significant difference in the percentage of circulating CD133(+) /CD34(+) cells was observed among all groups of patients. In liver tissues, OV6(+) cells increased significantly in Child-Pugh B cases (P < 0.05), while CD133(+) cells were distributed sparsely in the periportal region in Child-Pugh A and B patients. OV6(+) cells were significantly correlated with CD34(+) cells but not with CD133(+) cells in Child-Pugh A and B patients (P < 0.01 and P < 0.05, respectively).

CONCLUSIONS

Various degrees of severity in CLD neither evoked the mobilization of BMHSC into the circulation nor triggered their homing into liver tissue, thus excluding extrahepatic stem cell-mediated repair. The recovery process seems to be dependent on proliferating endogenous liver progenitors (OV6(+) cells).

Differential bone marrow hematopoietic stem cells mobilization in hepatectomized patients

BACKGROUND

The involvement of bone marrow hematopoietic stem cells (BMHSC) mobilization during liver regeneration from hepatectomized patients is under debate. The main aim of this study was to investigate the role of BMHSC mobilization after hepatic resection in 33 patients with liver disease.

METHODS AND RESULTS

Mobilization of CD34(+) BMHSC after 72 h of surgery was found in peripheral blood of some, but not all, of the hepatectomized patients. These CD34(+) cells co-expressed other stem cells markers. The patients without BMHSC mobilization showed high levels of circulating and liver tissue BMHSC (CD34(+) cells) previous to surgery. Therefore, two types of patients: "mobilizers" and "non-mobilizers" were distinguished based on the values of CD34(+) cells before and after surgery. Changes in cytokines involved in the hepatic regeneration (HGF and TGF-β), and in BMHSC mobilization process (SCF, SDF-1, IL-12, or MMP-2), were detected in both groups. In addition, a higher activation previous to surgery of the SDF-1/CXCR4 axis in liver tissue was observed in non mobilizers patients compared to mobilizer patients.

CONCLUSION

BMHSC mobilization seems to be associated with variations in the levels of cytokines and proteolytic enzymes involved in hepatic regeneration and bone marrow matrix degradation. Hepatectomy may be an insufficient stimulus for BMSHC mobilization. The pre-hepatectomy higher levels CD34(+) cells in peripheral blood and liver, associated to the activation of hepatic SDF-1/CXCR4 axis, suggest a BMHSC mobilization process previous to surgery in non mobilizer patients.