Disruption of the mouse Shmt2 gene confers embryonic anaemia via foetal liver-specific metabolomic disorders.

In a previous study, we proposed that age-related mitochondrial respiration defects observed in elderly subjects are partially due to age-associated downregulation of nuclear-encoded genes, including serine hydroxymethyltransferase 2 (SHMT2), which is involved in mitochondrial one-carbon (1C) metabolism. This assertion is supported by evidence that the disruption of mouse Shmt2 induces mitochondrial respiration defects in mouse embryonic fibroblasts generated from Shmt2-knockout E13.5 embryos experiencing anaemia and lethality. Here, we elucidated the potential mechanisms by which the disruption of this gene induces mitochondrial respiration defects and embryonic anaemia using Shmt2-knockout E13.5 embryos. The livers but not the brains of Shmt2-knockout E13.5 embryos presented mitochondrial respiration defects and growth retardation. Metabolomic profiling revealed that Shmt2 deficiency induced foetal liver-specific downregulation of 1C-metabolic pathways that create taurine and nucleotides required for mitochondrial respiratory function and cell division, respectively, resulting in the manifestation of mitochondrial respiration defects and growth retardation. Given that foetal livers function to produce erythroblasts in mouse embryos, growth retardation in foetal livers directly induced depletion of erythroblasts. By contrast, mitochondrial respiration defects in foetal livers also induced depletion of erythroblasts as a consequence of the inhibition of erythroblast differentiation, resulting in the manifestation of anaemia in Shmt2-knockout E13.5 embryos.

[Prenatal diagnosis and postnatal outcome of isolated intra-abdominal calcifications: A 10-year experience from a referral fetal medicine center]. / Diagnostic prénatal et issue néonatale des calcifications intra-abdominales isolées : étude rétrospective sur 10 ans.

INTRODUCTION: Intra-abdominal calcifications (iAC) detected during fetal ultrasound examinations are characterized by their isolated or associated nature, as well as their location. Our objective was to describe all cases of isolated iAC along with their etiological investigations and neonatal outcome, during a 10-year practice in a referral center. METHODS: We conducted a retrospective descriptive monocentric study on neonates diagnosed with isolated iAC after antenatal expert ultrasound scan and referred to the Multidisciplinary Center for Prenatal Diagnosis at Trousseau Hospital and born between January 1st, 2008 and June 30th, 2018. The exclusion criteria were: retroperitoneal calcifications, iAC associated with other digestive abnormalities or with congenital malformations. RESULTS: The 32 isolated iAC cases accounted for 46% of all iAC. Nine cases were excluded for missing neonatal data. Among the 23 remaining isolated iAC cases, we observed 15 intra-hepatic calcifications, 5 peri-hepatic and two peritoneal calcifications. One fetus had both intra- and peri-hepatic calcifications. The majority of iAC remained stable throughout pregnancy. No cases of aneuploidy, fetal infection, or cystic fibrosis were detected. The neonatal outcome was favorable in all cases. CONCLUSIONS: In case of isolated and stable iAC after expert ultrasound scan, after having ruled out infectious diseases of the fetus and looked for the most frequent mutations of cystic fibrosis in the parents, the prognosis is favorable. Fetal karyotyping is recommended when additional structural anomalies are present.

Isolated impact of liver herniation on outcome in fetuses with congenital diaphragmatic hernia - A matched-pair analysis based on fetal MRI relative lung volume.

PURPOSE: To evaluate liver-herniation as individual parameter on outcome in children with congenital diaphragmatic hernia. MATERIALS AND METHODS: In a retrospective matched-pair analysis based on observed to expected fetal lung volume (o/e FLV), birth weight, gestational age at time-point of examination, status of tracheal occlusion therapy and side of the defect the individual impact of liver-herniation on survival, need for extracorporeal membrane oxygenation (ECMO) therapy and chronic lung disease (CLD) was investigated. In total 61 pairs (122 patients) were included. Fisher's exact test was used to evaluate influence of liver-herniation and a p-value of <0.05 was defined as statistically significant. The study was approved by the local review board. RESULTS: Children with liver-herniation have lower survival rates (78.7% vs. 95.1%; p = 0.0073), need ECMO-therapy more often (41.0% vs. 16.4%; p = 0.0027) and are more likely to develop CLD (71.7% vs. 37.9%; p = 0.0004) than their corresponding matched-pair without liver-herniation. CONCLUSION: Liver-herniation itself and not further lung-volume restriction due to liver-herniation is responsible for poor outcome in CDH.

Three-dimensional assessment of umbilical vein deviation angle for prediction of liver herniation in left-sided congenital diaphragmatic hernia.

OBJECTIVES: To introduce a new sonographic marker of intrathoracic liver herniation in fetuses with left-sided congenital diaphragmatic hernia (CDH). METHODS: In a consecutive series of fetuses with isolated CDH, an ultrasound volume of the fetal abdomen was acquired. On this volume, offline calculation of the angle formed by the midline of the abdomen (joining the center of the vertebral body to the abdominal insertion of the umbilical cord) and a second line joining the center of the vertebral body to the intra-abdominal convexity of the umbilical vein was carried out to give the umbilical vein deviation angle (UVDA). The UVDA was measured in a group of normal fetuses selected as controls. At follow-up, the presence of liver herniation was investigated in all cases of CDH. UVDA values were compared between the CDH group and controls, and between CDH 'liver-up' vs 'liver-down' cases. A receiver-operating characteristics (ROC) curve was constructed to identify a cut-off value of the UVDA with the highest accuracy in predicting liver herniation in the CDH group. RESULTS: Between 2009 and 2015, 22 cases of left-sided CDH were included in the study group, of which nine cases had liver herniation. Eighty-eight normal fetuses were recruited as controls. The UVDA was significantly higher in the cases vs controls (15.25 ± 7.91° vs 7.68 ± 1.55°; P < 0.0001). Moreover, the UVDA was significantly increased in CDH fetuses with liver-up vs liver-down (21.77 ± 8.79° vs 10.75 ± 2.10°; P < 0.0001). On ROC curve analysis the UVDA showed good prediction of liver herniation (area under the ROC curve, 0.94; P < 0.0001) with the best cut-off of 15.2°, yielding a sensitivity of 89% and a specificity of 100% (P < 0.0001). CONCLUSIONS: In fetuses with CDH, umbilical vein bowing may be quantified by measuring the UVDA using three-dimensional ultrasound. This sonographic marker seems to be an accurate predictor of liver herniation in left-sided CDH. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

Quantification of liver herniation in fetuses with isolated congenital diaphragmatic hernia using two-dimensional ultrasonography.

OBJECTIVES: To describe a method of quantifying the amount of liver herniation in fetuses with isolated congenital diaphragmatic hernia (CDH) using two-dimensional ultrasonography and to correlate this finding with neonatal outcome. METHODS: Ultrasound images obtained from 77 consecutive fetuses that presented with isolated CDH between January 2004 and July 2012 were reviewed. Liver herniation and thoracic area were measured in a cross-sectional plane of the fetal chest at the level of the four-chamber view of the heart (the same section as is used to measure the lung area-to-head circumference ratio) and the ultrasound-derived liver-to-thoracic area ratio (US-LiTR) was calculated by dividing the liver herniation area by the thoracic area. Receiver-operating characteristics (ROC) curve analysis was used to evaluate the performance of US-LiTR in predicting neonatal outcome (survival to 6 months after delivery and need for extracorporeal membrane oxygenation (ECMO)). In addition, the US-LiTR was compared with the magnetic resonance imaging (MRI)-derived volume ratio (MRI-LiTR) and percentage of liver herniation (MRI-%LH). RESULTS: The overall neonatal mortality in the 77 cases with isolated CDH was 20.8% (16/77). ECMO was needed in 35.5% (27/76) of the newborns, with a survival rate of 52%. The US-LiTR was associated statistically with mortality (P < 0.01) and with the need for ECMO (P < 0.01). Good correlations were observed between US-LiTR and MRI-LiTR (r = 0.87; P < 0.001) and between US-LiTR and MRI-%LH (r = 0.90; P < 0.001). Based on ROC curve analysis, all three parameters had similar accuracy in predicting mortality (US-LiTR: area under the ROC curve (AUC), 0.78 (95% CI, 0.65-0.92), P < 0.01; MRI-LiTR: AUC, 0.77 (95% CI, 0.63-0.90), P < 0.01; MRI-%LH: AUC, 0.79 (95% CI, 0.65-0.92), P < 0.01, respectively) as well as the need for ECMO (US-LiTR: AUC, 0.72 (95% CI, 0.60-0.84), P < 0.01; MRI-LiTR: AUC, 0.73 (95% CI, 0.60-0.88), P < 0.01; MRI-%LH: AUC, 0.77 (95% CI, 0.64-0.89), P < 0.01, respectively). CONCLUSIONS: Two-dimensional ultrasound measurement of the amount of liver herniation in fetuses with isolated CDH is feasible and demonstrates a predictive accuracy for neonatal outcome similar to that of MRI.

Fetal lung volume and quantification of liver herniation by magnetic resonance imaging in isolated congenital diaphragmatic hernia.

OBJECTIVE: To determine associations between fetal lung and liver herniation volumes measured by magnetic resonance imaging (MRI) and mortality/need for extracorporeal membrane oxygenation (ECMO) in cases of isolated congenital diaphragmatic hernia (CDH). A secondary objective was to compare prenatal MRI parameters with two-dimensional ultrasound lung measurements. METHODS: A retrospective review of medical records of all fetuses with isolated CDH evaluated between January 2004 and July 2012 was performed. The following MRI parameters were measured at 20-32 weeks: observed/expected total fetal lung volume (o/e-TLV), predicted pulmonary volume (PPV), percentage of liver herniated into the fetal thorax (%LH) and the liver/thoracic volume ratio (LiTR). These were compared with the ultrasound-determined lung-to-head ratio (LHR) and the observed/expected LHR (o/e-LHR) in the same cohort. The predictive value of MRI and ultrasound parameters for mortality and the need for ECMO was evaluated by univariate, multivariate and factor analysis and by receiver-operating characteristics curves. RESULTS: Eighty fetuses with isolated CDH were evaluated. Overall mortality was 18/80 (22.5%). Two newborns died a few hours after birth. ECMO was performed in 29/78 (37.2%) newborns, with a survival rate of 48.3% (14/29). The side of the diaphragmatic defect was not associated with mortality (P = 0.99) or the need for ECMO (P = 0.48). Good correlation was observed among o/e-TLV, PPV, LHR and o/e-LHR as well as between %LH and LiTR (r = 0.89; P < 0.01); however, fetal lung measurements and measures of liver herniation were not correlated (all P > 0.05). All parameters were statistically associated with mortality or the need for ECMO. The best combination of measurements to predict mortality was o/e-TLV and %LH, with 83% accuracy. CONCLUSION: Mortality and the need for ECMO in neonates with isolated CDH can be best predicted using a combination of MRI o/e-TLV and %LH.

Intrablastocyst injection with human CD34+/CD133+ cells increase survival of immunocompetent fumarylacetoacetate hydrolase knockout mice.

Mice harbouring a humanized liver represent a powerful tool for translating preclinical studies of drug metabolism and pharmacokinetics into humans, as well as the exploitation of basic studies on liver pathophysiology including hepatitis C virus (HCV) infection. Human adult stem cells injected into immunocompetent mice at preimmune stages of development, generate chimeric animals harbouring a liver with relatively discrete foci of human hepatocyte-like cells. In this study, we have evaluated whether similar protocol of xenotransplantation in the presence of selective pressure might lead to a higher human-into-mouse liver repopulation, leading to a relevant improvement of liver function. Human CD34(+)/CD133(+) cells were microinjected into blastocysts from genetically-modified mice committed to develop a lethal hepatopathy, due to the absence of the enzyme fumarylacetoacetate hydrolase (FAH). Following xenotransplantation, mouse survival was followed over time and histochemical evidence of liver chimerism was assessed. The survival expectancy of seven out of 21 intrablastocyst xenotransplanted FAH knockout (Fah-/-) mice was significantly higher as compared with non-xenotransplanted mice. Several nodules of human hepatocyte-like cells were revealed by immunohistochemistry in the liver of rescued mice. Our data positively support the hypothesis that preimmune xenotransplantation of human stem cells into immunocompetent mice harbouring a lethal hepatic disease might lead to a functionally relevant human-mouse liver chimerism and marks a significant advancement towards the establishment of a novel translational preclinical model for liver diseases.

Increase in fetal pulmonary artery diameters during late gestation is a predictor of outcome in congenital diaphragmatic hernia with liver herniation.

AIM: Liver herniation (LH) in congenital diaphragmatic hernia (CDH) may not be a reliable prognostic indicator. We measured pulmonary artery (PA) diameters in CDH + LH as an alternative. METHODS: Of 41 consecutive cases of prenatally diagnosed left-sided CDH treated from 2002 to 2010, 19 had CDH + LH and 22 had CDH - LH. Ultrasonography and magnetic resonance imaging were used to assess LH and echocardiography to measure PA diameters during the third trimester (fetal; 32-34 weeks), at birth, and on day 2 of life. RESULTS: In CDH + LH survivors (9/19; 47%), fetal right PA (RPA) diameters were significantly larger than in nonsurvivors (2.58 ± 0.56 vs 1.82 ± 0.35 mm; P < .01), but left PA (LPA) diameters were not (1.73 ± 0.38 vs 1.59 ± 0.22). In survivors, fetal RPA was greater than 2 mm in all but one case, and both PA diameters increased significantly by birth (RPA, 2.58 ± 0.56 vs 3.52 ± 0.54; LPA, 1.73 ± 0.38 vs 2.60 ± 0.40; both P < .01). Final diameters at birth in survivors were at least 2.5 and 2.0 mm, respectively. In nonsurvivors, both PAs were significantly smaller (RPA, 3.52 ± 0.54 vs 2.04 ± 0.31; LPA, 2.60 ± 0.40 vs 1.68 ± 0.18; P < .01), with no observed increase by birth. Survival in CDH - LH was 82% (18/22). CONCLUSION: PA diameter appears to be correlated with prognosis in infants with CDH + LH.

Liver herniation in gastroschisis: incidence and prognosis.

PURPOSE: Liver herniation is a rare occurrence in gastroschisis. We sought to determine the incidence and prognosis of liver herniation in patients with gastroschisis. METHODS: From December 1995 to March 2010, 117 patients with gastroschisis received care by our division. Operative reports were reviewed to identify patients with liver herniation. Logistic regression was used to determine the impact of liver herniation on survival, taking into account gestational age and birth weight. RESULTS: The incidence of liver herniation was 6%. Survival rates were 43% with liver herniation and 97% without liver herniation. Liver herniation was associated with a significantly higher rate of mortality, taking into account estimated gestational age and birth weight (P < .001). Patients who had liver herniation documented by prenatal ultrasound had significant liver herniation at birth and died postnatally. Patients with liver herniation who died required large silos and were noted to have comorbidities including lower birth weight, pulmonary hypoplasia, and sepsis. Biologic patches were necessary for closure in patients with greater extent of liver herniation. CONCLUSIONS: Liver herniation was found in 6% of patients with gastroschisis and was associated with a high rate of mortality. Liver herniation appears to be a risk factor for poor outcome in gastroschisis. Documentation of liver herniation may be helpful in prenatal consultation for gastroschisis.

MicroRNAs are necessary for vascular smooth muscle growth, differentiation, and function.

OBJECTIVE: Regulation of vascular smooth muscle (VSM) proliferation and contractile differentiation is an important factor in vascular development and subsequent cardiovascular diseases. Recently, microRNAs (miRNAs) have been shown to regulate fundamental cellular processes in a number of cell types, but the integrated role of miRNAs in VSM in blood vessels is unknown. Here, we investigated the role of miRNAs in VSM by deleting the rate-limiting enzyme in miRNA synthesis, Dicer. METHODS AND RESULTS: Deletion of Dicer in VSM results in late embryonic lethality at embryonic day 16 to 17, associated with extensive internal hemorrhage. The loss of VSM Dicer results in dilated, thin-walled blood vessels caused by a reduction in cellular proliferation. In addition, blood vessels from VSM-deleted Dicer mice exhibited impaired contractility because of a loss of contractile protein markers. We found this effect to be associated with a loss of actin stress fibers and partly rescued by overexpression of microRNA (miR)-145 or myocardin. CONCLUSIONS: Dicer-dependent miRNAs are important for VSM development and function by regulating proliferation and contractile differentiation.

Relationship of proximal renal tubular dysgenesis and fetal liver injury in neonatal hemochromatosis.

Renal tubular dysgenesis has been reported in isolated cases of neonatal hemochromatosis (NH). We hypothesized that fetal liver injury in NH impairs proximal renal tubular development via impaired hepatic angiotensinogen (AGT) elaboration. Morphometric analyses were performed of postmortem liver and kidney sections of cases of proven NH and postconception age-matched controls for renal proximal tubule density, hepatocyte mass, and hepatic AGT expression. Proximal tubule density was markedly reduced in NH cases, although they showed a spectrum from mild to severe paucity. Hepatic AGT expression was markedly reduced in NH cases and correlated closely with reduced hepatocyte mass. A linear relationship was established between hepatic AGT expression and the degree of renal tubular dysgenesis suggesting that there is a relationship between them. Our results demonstrate that there is a spectrum of kidney pathology in patients with NH including a large proportion of cases with severe proximal tubular dysgenesis. Hepatic synthetic failure resulting in insufficient production of AGT to support renal tubular development is the likely mechanism of kidney disease in NH.

Mechanisms of liver development: concepts for understanding liver disorders and design of novel therapies.

The study of liver development has significantly contributed to developmental concepts about morphogenesis and differentiation of other organs. Knowledge of the mechanisms that regulate hepatic epithelial cell differentiation has been essential in creating efficient cell culture protocols for programmed differentiation of stem cells to hepatocytes as well as developing cell transplantation therapies. Such knowledge also provides a basis for the understanding of human congenital diseases. Importantly, much of our understanding of organ development has arisen from analyses of patients with liver deficiencies. We review how the liver develops in the embryo and discuss the concepts that operate during this process. We focus on the mechanisms that control the differentiation and organization of the hepatocytes and cholangiocytes and refer to other reviews for the development of nonepithelial tissue in the liver. Much progress in the characterization of liver development has been the result of genetic studies of human diseases; gaining a better understanding of these mechanisms could lead to new therapeutic approaches for patients with liver disorders.

Significance of early prenatal diagnosis of fetal hepatic cyst.

PURPOSE: : To summarize our experience of early prenatal diagnosis of fetal hepatic cysts. METHOD: : We reviewed all cases of fetal hepatic cyst detected in our institution between 13 and 17 weeks' gestation over the last 20 years. All scans were initially performed transvaginally to improve image quality. Most of the scans were performed as a routine fetal anatomy scan in a low-risk population. RESULTS: : Seven fetal hepatic cysts were detected out of 54,500 fetal anatomy scans performed between 13 and 17 weeks' gestation. Five peripheral cysts measuring 3-5 mm disappeared during the follow-up period, between 18 and 24 weeks' gestation. Two hilar cysts appeared on sonography as choledochal cysts; one disappeared at 22 weeks' gestation, and the other diminished in size during the postnatal follow-up. CONCLUSION: : Based on our experience, when hepatic cysts are diagnosed during an early fetal anatomy scan, disappearance of these cysts can be expected, especially when the cysts are initially small and peripheral. (c) 2008 Wiley Periodicals, Inc. J Clin Ultrasound, 2009.

Abnormalities in the myeloid progenitor compartment in Down syndrome fetal liver precede acquisition of GATA1 mutations.

Down syndrome (DS) children have a high frequency of acute megakaryoblastic leukemia (AMKL) in early childhood. At least 2 in utero genetic events are required, although not sufficient, for DS-AMKL: trisomy 21 (T21) and N-terminal-truncating GATA1 mutations. To investigate the role of T21 in DS-AMKL, we compared second trimester hemopoiesis in DS without GATA1 mutations to gestation-matched normal controls. In all DS fetal livers (FLs), but not marrows, megakaryocyte-erythroid progenitor frequency was increased (55.9% +/- 4% vs 17.1% +/- 3%, CD34(+)CD38(+) cells; P < .001) with common myeloid progenitors (19.6% +/- 2% vs 44.0% +/- 7%) and granulocyte-monocyte (GM) progenitors (15.8% +/- 4% vs 34.5% +/- 9%) commensurately reduced. Clonogenicity of DS-FL versus normal FL CD34(+) cells was markedly increased (78% +/- 7% vs 15% +/- 3%) affecting megakaryocyte-erythroid ( approximately 7-fold higher) and GM and colony-forming unit-granulocyte, erythrocyte macrophage, megakaryocyte (CFU-GEMM) progenitors. Replating efficiency of CFU-GEMM was also markedly increased. These data indicate that T21 itself profoundly disturbs FL hemopoiesis and they provide a testable hypothesis to explain the increased susceptibility to GATA1 mutations in DS-AMKL and DS-associated transient myeloproliferative disorder.

Secondary cytomegalovirus infection can cause severe fetal sequelae despite maternal preconceptional immunity.

OBJECTIVES: To describe our experience in cases with sonographic signs of fetal infection and with maternal serological 'immunity' to cytomegalovirus (CMV) infection. METHODS: This was a bicenter study of six pregnant women referred for evaluation of suspected fetal infection. All cases had confirmed maternal serology for past exposure to CMV but no evidence of recent secondary CMV infection. All underwent sonographic evaluation as well as complete investigation for CMV infection. RESULTS: The mean age of the women was 29 (range, 23-35) years and the mean gestational age at diagnosis was 23.5 weeks (range, 20-31) weeks. Sonographic findings included microcephaly, ventriculomegaly, periventricular calcifications and cystic lesions, echogenic bowel, hydrops and hepatosplenomegaly. Amniocentesis was performed in all cases for fetal karyotyping and viral assessment, and all were found by polymerase chain reaction to be positive for CMV infection. Four pregnancies were terminated following the parents' request. One pregnancy continued until intrauterine fetal death occurred 2 weeks after diagnosis. Postmortem was denied in all cases but one. One infant was delivered with evidence of severe cerebral palsy. CONCLUSION: In the presence of sonographic findings suggestive of fetal CMV infection, prompt investigation of amniotic fluid should follow even if maternal serology does not support recent maternal seroconversion.

The associations between birthweight and adult markers of liver damage and function.

Evidence suggesting an effect of fetal growth on liver development and function stems from both animal and human studies. The association of birthweight with adult markers of liver damage and function was examined in a random sample of 2101 British women aged 60-79 years. Age-adjusted natural logged levels of alanine aminotransferase (ALT) and gamma glutamyltransferase (GGT) decreased linearly across increasing thirds of birthweight. Alkaline phosphatase (ALP) levels were higher in women of the lowest third of the birthweight distribution compared with other women. No evidence was found for associations of birthweight with aspartate aminotransferase (AST), total bilirubin and albumin. After full adjustment for social class, physical activity, smoking and alcohol consumption, an increase in one standard deviation of birthweight (691 g) was associated with a 2% ([95% CI 0%, 4%], P = 0.021) decrease in the geometric mean of ALT, a 4% decrease in GGT ([95% CI 1%, 6%], P = 0.008) and a 2% decrease in ALP ([95% CI 0%, 3%], P = 0.001). Associations of birthweight with ALT and GGT, but not with ALP, were attenuated when adjusting for components of the metabolic syndrome. These findings suggest that factors affecting intrauterine growth may increase the propensity for adult liver damage. The attenuation of associations with adjustment for components of the metabolic syndrome is in line with non-alcoholic fatty liver disease, indicated by elevated ALT and GGT, being the hepatic manifestation of the metabolic syndrome, and of the influence of perinatal factors on this syndrome.

In utero transplantation of human hematopoietic stem/progenitor cells partially repairs injured liver in mice.

The aim of this study is to establish a novel mouse model with high achievement and chimerism by in utero transplantation of human hematopoietic stem/progenitor cells and to explore the possibility that human adult hematopoietic stem/progenitor cells can differentiate into hepatocyte-like cells and partially repair the liver damage induced by carbon tetrachloride (CCl(4)). Mononuclear cells (MNCs) were isolated from fresh human umbilical cord blood (hUCB) and CD34(+) cells were enriched from the MNCs by magnetic cell isolation. These cells were injected respectively into the fetal mice at 11-13 days of gestation. At one month after birth, the specific markers of human cells, human alpha-satellite sequence (h17alpha), CD14, CD34, CD45, and GPA were detected by PCR and FACS. At three and six months after birth, the established human-mouse chimeras were administered with CCl(4) by intraperitoneal injection. The biochemical markers (ALT, AST, ALP, albumin) in serum were determined and human hepatocyte-specific proteins, such as human albumin, hepatocyte nuclear factor-4, hepatocyte-specific antigen, tryptophan 2,3-dioxygenase and alpha fetoprotein were analyzed by PCR, RT-PCR, real-time PCR and immunohistochemistry staining, respectively. More than 77% of recipients demonstrated human-mouse chimera. Significantly, hUCB hematopoietic stem/progenitor cells may differentiate into human hepatocyte-like cells with evidence of the expression of human hepatocyte-specific proteins as well as partially repair or protect liver damage induced by CCl(4). The mouse model described in this article provides a useful tool for the studies of regeneration of human hepatocyte-like cells from adult hematopoietic stem/ progenitor cells as well as facilitates the therapeutic potential for liver diseases or damage by in utero transplantation.