Little evidence of bone marrow-derived hepatocytes in the replacement of injured liver

Abstract

We have tested the ability of bone marrow (BM) cells (BMCs) to form hepatocytes in liver injury models. We used three models: T here have been a number of reports that show the potential of adult rodent bone marrow (BM) cells (BMCs) to transdifferentiate into a variety of cell types (1-7), including hepatocytes (8 -10). One of the best examples for the transdifferentiation has been the ability of BM-derived hapatocytes to repopulate the liver of mice with fumarylacetoacetate hydrolase knockout mouse (FAHϪ͞Ϫ) and correct the liver disease (10), although recent reports have shown that this correction of liver disease is caused by fusion of donor BM to recipient hepatocytes rather than transdifferentiation (11,12). However, it is not fully elucidated whether or not the significant level of the contribution of BM-derived hepatocytes in the FAHϪ͞Ϫ model, either in the form of transdifferentiation or cell fusion, can be generalized in other liver injury models. Here we report our results with nonselective liver injury model and two selective liver injury models {carbon tetrachloride (CCl 4 ), albumin-urokinase transgenic mouse [TgN(Alb1Plau)] (13), and hepatitis B transgenic mouse [TgN(Alb1HBV)] (14)}, to examine how general is the phenomenon of the repopulation by BM-derived hepatocytes. It is of considerable clinical importance to know the level of contribution of BM-derived hepatocytes in a slowly progressive chronic liver disease model like TgN(Alb1HBV), because chronic viral hepatitis is a leading cause of cirrhosis and hepatocellular carcinoma worldwide (15, 16). (13) and TgN(Alb1Plau) were purchased from The Jackson Laboratory, and the latter was back-crossed to C57BL͞6J (B6) (The Jackson Laboratory). Animal study protocols were approved by The Salk Institute Animal Care and Use Committee. Donor mice used in these studies were generally 7-8 weeks old, and recipient animals were 8 -12 weeks old except for neonatal transplantation. Biochemical analysis of serum from animal was performed by ANILYTICS (Anilytics, Gaithersburg, MD). Neonatal BM Transplantation. After whole-body irradiation with 200-400 cG, neonatal recipient mice (1-5 days of age) were injected with BMCs through the superficial temporal vein by using hypothermic anesthesia. Materials and MethodsCCl4 Liver Injury. B6 mice were i.p. injected with CCl 4 (0.02-1.0 ml͞kg of animal weight, twice a week, total of eight times).Choline-Deficient, Ethionine-Supplemented Diet. Mice were administered a diet consisting of a 1:1 mixture of choline-deficient chow (ICN) and normal chow and drinking water supplemented with 0.15% (wt͞vol) DL-ethionine (ICN) for 2 weeks (18).Tissue Preparation. Transplanted animals were anesthetized and perfused intracardially with 4% paraformaldehyde͞PBS. Perfused livers were dissected and further fixed in 4% paraformaldehyde at 4°C overnight. In some cases, animals were killed, and thin liver slices (2-3 mm) were removed immediately. Portions of the liver slices were snap-frozen, and the other slices were fixed in 4% paraformaldehy...

Transplanted bone marrow stromal cells are not cellular origin of hepatocellular carcinomas in a mouse model of carcinogenesis

“…Bone marrow-derived hepatocytes may originate from the mesenchymal compartment, rather than the hematopoietic compartment [22] . However, other data demonstrate that bone marrow-derived hepatocyte is only a possible but rare event, even in the presence of very strong selection pressure [23] . Several reports have demonstrated that cell fusion is the principal source of bone marrow-derived hepatocytes [24] , and bone marrow-derived hepatocytes are primarily of mature myelomonocytic cells which fuse spontaneously with host hepatocytes producing functional liver repopulation [14] .…”

Hematopoietic Stem Cell Mobilization Therapy Accelerates Recovery of Renal Function Independent of Stem Cell Contribution

“…Detection of y chromosomes was performed on 6-m cryostat sections, using a mouse Y chromosome-specific FITC-labeled probe (Starfish; Cambio, Cambridge, UK) following the procedure described by Kanazawa et al (10). Sections then were washed according to the manufacturer's instructions.…”

Evaluation of the effect of transplant-related factors and tissue injury on donor-derived hepatocyte and gastrointestinal epithelial cell repopulation following hematopoietic cell transplantation

“…[1][2][3][4]7,21,22 In the present study, no relationship between tissue injury due to either conditioning regimen or the extent of GVHD and the presence and proportion of donor-derived hepatocyte and gastrointestinal epithelial cell repopulation was observed, although the proportion of donor-derived hepatocyte and gastrointestinal epithelial cell repopulation in individuals with severe GVHD was slightly greater. Kanazawa et al 23 and Korbling et al 7 reported that the frequency of DDHR in recipients is unrelated to liver injury in both experimental models and humans. In contrast, Theise et al 1 reported that the extent of engraftment in sex-mismatched graft seems to correlate with the severity of tissue injury.…”

“…Basic concepts on stem cell biology including plasticity, transdifferentiation and fusion have all been reported. 1,2,5,[22][23][24][25][26][27][28][29] Recent progresses in stem cell studies have indicated that certain mammalian cells maintain a high degree of plasticity for multilineage cell differentiation. 25,26 The plasticity is supported by the finding of intrahepatic chimerism in transplant recipients.…”