The significance of serum hepatocyte growth factor levels in planning follow-up of postoperative jaundice-free patients with biliary atresia

Elevated serum IL-34 is correlated with disease severity in patients with biliary atresia following Kasai portoenterostomy

BACKGROUND

Biliary atresia (BA) is a severe congenital disorder with progressive obstructive cholangiopathy in young children. The inflammatory process has been recognized as one of the pathological mechanisms driving bile duct injury. Since interleukin-34 (IL-34) has been reportedly linked to several pathological liver disorders, including inflammation, the current study aimed to analyze circulating IL-34 and the association of circulating IL-34 with hepatic deterioration and clinical outcomes in post-Kasai BA children.

METHODS

Circulating IL-34 levels were analyzed in 89 post-Kasai BA subjects and 45 healthy individuals using an ELISA. Liver stiffness (hardness) was measured by ultrasound elastography.

RESULTS

Circulating IL-34 was substantially higher in BA children than in control individuals, particularly those with unfavorable outcomes including hepatic dysfunction, jaundice, and portal hypertension. In BA group, circulating IL-34 was positively correlated with liver stiffness (r = 0.515, p < 0.001), AST (r = 0.403, p < 0.001), ALT (r = 0.279, p = 0.008), total bilirubin (r = 0.224, p = 0.03), ALP (r = 0.255, p = 0.016), and serum IL-6 (r = 0.590, p < 0.001) but inversely correlated with albumin (r = -0.417, p < 0.001). Kaplan-Meier survival analysis showed that higher circulating IL-34 levels were significantly associated with reduced survival rates in BA subjects (p = 0.002).

CONCLUSION

Higher circulating IL-34 values were directly associated with hepatic impairment and the BA severity, implicating thatserum IL-34 could be applied as a noninvasive marker for the monitoring of the severity in BA subjects following Kasai portoenterostomy and therapeutic efficacy.

Systemic cytokine profiles in biliary atresia

Background

Inflammation and immune dysregulation persuade biliary duct injury in biliary atresia (BA), a leading cause of pediatric liver transplantation given lack of specific biomarkers. We aimed to determine associations between systemic cytokine profiles and clinical parameters in BA patients and to identify potential BA biomarkers.

Methods

Systemic levels of 27 cytokines were measured in 82 BA patients and 25 healthy controls using a multiplex immunoassay. Relative mRNA expressions of candidate cytokines in 20 BA livers and 5 non-BA livers were assessed using quantitative real-time PCR.

Results

Higher levels of 17 cytokines including IL-1β, IL-6, IL-7, IL-8, IL-9, IL-2, IL-15, eotaxin, IP-10, MCP-1, MIP-1α, MIP-1β, G-CSF, IL-1ra, IL-4, IL-5, and IL-10 and lower levels of IFN-α and PDGF were significantly associated with BA. In BA patients, increased levels of IL-7, eotaxin, IP-10, and IL-13 were significantly associated with unfavorable outcomes including jaundice, fibrosis, and portal hypertension. Indeed, systemic levels of those cytokines were significantly correlated with clinical parameters indicating jaundice, fibrosis, and hepatic dysfunction in BA patients. Out of 27 cytokines, 4 (IL-8, IP-10, MCP-1, and PDGF) had potential as sensitive and specific biomarkers of BA. Of these, higher IL-8 levels were significantly associated with reduced survival of BA. In BA livers, relative mRNA expressions of IL-8, IP-10, and MCP-1 were significantly up-regulated.

Conclusions

Higher levels of several cytokines including inflammatory cytokines, immunomodulatory cytokines, chemokines, and anti-inflammatory cytokines and lower levels of growth factors would reflect inflammatory and immune responses related to BA development. Among 27 cytokines, plasma IL-8 might have great potential as a diagnostic and prognostic biomarker for BA.

Hepatic expression of HGF/C-met and native liver survival in biliary atresia

BACKGROUND

The prognosis of biliary atresia (BA) remains difficult to predict. This study evaluated the roles of hepatocyte growth factor (HGF) and its receptor (C-met) towards clinical outcome and native liver survival.

METHODS

Hepatic HGF and C-met expression were determined using immunohistochemistry from liver biopsies of 41 BA patients during Kasai operation, and 17 non-cholestatic patients. The HGF and C-met expression was visually scored as per its intensity and percentage of stained area. BA patients were classified as high- and low-HGF and C-met receptor status. Native liver survival was compared between the two groups at 3-year follow-up. Data are shown as median and range.

MAIN RESULTS

Median age of BA patients was 2 (1-6) months. Hepatic HGF and C-met staining scores of BA patients were higher than those of non-cholestatic patients (P < 0.0001). There was a correlation between HGF and C-met staining scores (spearman r = 0.77, P < 0.0001). However, there was no association between their expression and early outcome at 6 months post-op. Mean follow-up time was 68.6 months. Survival analysis revealed that native liver survival at 1 year and 3 years were 88% and 77%, respectively. Additionally, 82.6% (19/23) of patients in the low-HGF group survived with native liver, compared with 66.7% (10/15) of those in high-HGF group (P = 0.436). For C-met expression, 78.6% (22/28) of low-score and 70% (7/10) of high score groups survived with native liver (P = 0.673).

CONCLUSIONS

Strong expression of hepatic HGF and its receptor in BA patients was demonstrated. However, the expression was not associated with the early outcome and native liver survival. These results suggest that HGF involved in the liver pathology of BA but its expression cannot be used as a prognostic indicator. Small sample size of patients was a main limitation. Further studies are warranted to validate our findings.

Hepatocyte growth factor levels in livers and serum at Kasai-portoenterostomy are not predictive of clinical outcome in infants with biliary atresia

Biliary atresia (BA) is characterized by progressive destruction of the biliary system leading to liver fibrosis and deterioration of liver function. Serum hepatocyte growth factor (HGF) has been shown to be increased in cirrhotic diseases including BA. The aim of this study was to investigate the prognostic value of HGF levels in sera and liver tissue for the further disease course. A total of 49 serum and liver samples from infants with BA were acquired during Kasai-portoenterostomy (KPE) and analyzed by multiplex immunoassay including HGF, as marker of liver regeneration, and Interleukin 6 (IL-6) as a marker of inflammation. Both mediators showed no correlation with the outcome defined as favorable (survival with native liver (SNL)) or, in contrast, rapid deterioration of liver function requiring transplantation. Our data suggest that the degree of liver regeneration indicated by high levels of HGF within the liver is a dismissible factor in the post-KPE disease course.

Multiple orifices and cholangiography with a "fire-like" appearance after Kasai hepatoportoenterostomy for biliary atresia

A 21-year-old female underwent a Kasai hepatoportoenterostomy with Roux-en-Y reconstruction for typeIII biliary atresia at age 63 days. At the age of 19 years, she developed cholangitis and CT scan revealed hepatolithiasis. She presented for treatment of the intrahepatic stone and the hepatportoenterostomy was directly visualized with double-balloon endoscopy (DBE). Endoscopic findings showed multiple intrahepatic bile ducts open to the jejunum through multiple orifices. Cholangiography showed narrowing of intrahepatic bile duct branches with a "fire-like" appearance. These findings have not been previously reported, since endoscopic approaches to patients with a hepaticojejunostomy were limited. DBE was useful to directly visualize the anastomosis in a patient status-post the Kasai operation for biliary atresia with a Rouxen-Y reconstruction.

Persistent elevation of hepatocyte growth factor activator inhibitors in cholangiopathies affects liver fibrosis and differentiation

Alteration of cell surface proteolysis has been proposed to play a role in liver fibrosis, a grave complication of biliary atresia (BA). In this study we investigated the roles of hepatocyte growth factor activator inhibitor (HAI)-1 and -2 in the progression of BA. The expression levels of HAI-1 and -2 were significantly increased in BA livers compared with those in neonatal hepatitis and correlated with disease progression. In BA livers, HAI-1 and -2 were coexpressed in cells involved in ductular reactions. In other selective cholangiopathies, ductular cells positive for HAI-1 or HAI-2 also increased in number. Inflammatory cytokines, growth factors, and bile acids differentially up-regulated expression of HAI-1 and -2 transcripts in fetal liver cells and this induction could be antagonized by a cyclooxygenase-2 inhibitor. Conditioned media from cell lines stably overexpressing HAI-1 or HAI-2 enhanced the fibrogenic activity of portal fibroblasts and stellate cells, suggesting that both proteins might be involved in liver fibrosis. Because HAI-1 and -2 colocalized in ductular reactions sharing similar features to those observed during normal liver development, we sought to investigate the role of HAI-1 and -2 in cholangiopathies by exploring their functions in fetal liver cells. Knockdown of HAI-1 or HAI-2 promoted bidirectional differentiation of hepatoblast-derived cells. In addition, we showed that the hepatocyte growth factor activator, mitogen-activated protein kinase kinase 1, and phosphatidylinositol 3-kinase signaling pathways were involved in hepatic differentiation enhanced by HAI-2 knockdown.

CONCLUSION

HAI-1 and -2 are overexpressed in the liver in cholangiopathies with ductular reactions and are possibly involved in liver fibrosis and hepatic differentiation; they could be investigated as disease markers and potential therapeutic targets.

Bone health in a nonjaundiced population of children with biliary atresia

Objectives. To assess bone health in a cohort of nonjaundiced children with biliary atresia (BA) and the effect of growth and development on bone outcomes. Methods. Children ages one to eighteen years receiving care from Children's Hospital of Philadelphia were recruited. Each child was seen once and assessed for growth, pubertal development, concurrent medications, bilirubin, ALT, albumin, vitamin D status, bone mineral density (BMD), and bone mineral content (BMC) of the lumbar spine and whole body. Results. BMD declined significantly with age, and upon further analysis with a well-phenotyped control cohort, it was found that BMC was significantly decreased for both lumbar spine and whole body, even after adjustment for confounding variables. An age interaction was identified, with older subjects having a significantly greater impairment in BMC. Conclusions. These preliminary results demonstrate that children with BA, including those without jaundice, are likely to have compromised bone health even when accounting for height and puberty, which are common confounding factors in chronic disease. Further investigation is needed to identify the determinants of poor bone mineral status and to develop strategies to prevent osteoporosis later in life.

Evaluation of hepatocyte growth factor in patients with biliary atresia

BACKGROUND

Hepatocyte growth factor (HGF) is a potent mitogen for mature hepatocytes in primary culture and seems to be a trigger factor for liver regeneration and proliferation after liver injury. The aim of this study was to evaluate the expression of HGF in patients with biliary atresia (BA).

METHODS

Plasma levels of HGF were determined using an enzyme-linked immunosorbent assay from 19 patients with BA, 10 at the time of Kasai procedure (KP) and 9 at liver transplantation (LT), and 10 patients with nonicteric choledochal cyst served as control. Hepatic HGF level was quantitatively estimated using enzyme-linked immunosorbent assay and Western blotting. Hepatocyte growth factor messenger RNA (mRNA) expression of liver was measured with quantitative reverse transcriptase polymerase chain reaction. Immunohistochemical study of liver sections was evaluated by HGF staining.

RESULTS

Plasma HGF levels in LT patients were significantly higher than in KP patients (2977.30 +/- 1251.42 vs 960.17 +/- 559.82 pg/mL, P < .01). Western blots showed increased hepatic HGF levels in LT group than in KP group (2.02 +/- 0.86 vs 1.44 +/- 0.72 pg/mug total protein, P < .05). However, there were no differences in HGF mRNA expression. Immunohistochemical study showed significantly increased HGF staining in hepatocytes of LT livers than of KP livers.

CONCLUSIONS

Elevation of plasma and liver HGF levels could be related to the progression of liver cirrhosis in patients with BA. Hepatocyte growth factor might have a protective role, probably through the induction of hepatocyte proliferation, during the development of BA-associated liver cirrhosis.