Hepatic Fibrosis
Staff
Funding
Collaborators
Key Recent Publications
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Lab Head: Associate Professor Grant A. Ramm
The Hepatic Fibrosis Group is principally involved in investigating the cell
biology of hepatic stellate cells (HSC). HSC are transformed into myofibroblasts
when exposed to liver toxins such as excess iron, alcohol, or bile salts
due to cholestasis, viral infection or tumour invasion. HSC are responsible
for excess collagen deposition, fibrosis and cirrhosis in liver injury.
Over the past 18 months our studies have established that HSC are responsible
for liver cirrhosis in a subset of patients with cystic fibrosis. We are
currently investigating the role of chemoattraction as a mechanism for
HSC migration and inflammatory cell infiltration of the peri-ductular
region of the acinus in cystic fibrosis liver disease and biliary atresia.
We have identified a number of potential serum markers of early fibrogenesis
in these patients and are currently investigating their utility in clinical
practice. Our work has also demonstrated a role for the iron-storage protein
ferritin in the cytokine-like regulation of HSC activation, through the
activation and translocation of NFkB. We believe that ferritin and another
iron-binding protein, transferrin, may be involved in the development
of fibrosis in haemochromatosis and we are currently investigating the
cell signalling pathways which may be involved in HSC activation in iron
overload.
Matrix synthesis and degradation: role of hepatic stellate cells
in fibrogenesis associated with Haemochromatosis
We have shown that hepatic stellate cells are activated in haemochromatosis
liver and that removing excess hepatic iron by venesection therapy results
in the disappearance of the activated hepatic stellate cell phenotype
(Ramm et al, 1997). We have also demonstrated that extracellular matrix
components produced by hepatic stellate cells, such as collagen type IV,
can be detected in the serum and are useful markers of the severity of
fibrosis (George et al, 1998; George et al, 1999). Our recent work has
shown a potential involvement for interferon-g in this disease suggesting
that a submorphological inflammatory process may regulate hepatic stellate
cell activation. Current studies centre around the role of the matrix
degradation enzymes, matrix metalloproteinases (MMPs) and their regulating
inhibitors, tissue inhibitors of MMPs (TIMPs) in stimulating hepatic stellate
cells to activate and become profibrogenic.
Pathways
of iron metabolism in hepatic stellate cells
We have shown that the iron-storage protein ferritin regulates the expression
of the contractile protein a-smooth muscle actin in activated hepatic
stellate cells (Ramm et al, 1994: Ramm et al, 1996). Recent studies have
demonstrated that another iron protein, transferrin, appears to regulate
the expression of collagen type I which may suggest a potential mechanism
of hepatic stellate cell activation in haemochromatosis. This study is
currently evaluating the role of transferrin and ferritin in the iron-induced
activation of hepatic stellate cells. We have shown that the nuclear transcription
factor, NFkB is activated and translocates to the nucleus of hepatic stellate
cells following exposure to ferritin. It is hoped that an understanding
of the basic iron biology of hepatic stellate cells may lead to strategies
designed to abrogate the processes of fibrogenesis in haemochromatosis.
Expression of iron transporters in haemochromatosis
This project is designed to examine the expression and tissue and cellular
distribution of a number of iron transporter proteins thought to be involved
in the iron overload disease, haemochromatosis, such as HFE, DMT-1, Ireg,
and hephaestin. These observations coupled together with collaborative
work with Dr Greg Anderson and Dr Nathan Subramaniam from the Population
Health and Clinical Sciences Division at QIMR, will assist in gaining
a greater understanding of the mechanisms associated with excessive iron
absorption from the intestine and iron deposition in the liver in subjects
with this disease. Our ultimate goal in this project is to develop novel
therapeutic strategies designed either inhibit excess iron absorption
or deposition or indeed promote accelerated iron removal from the body
in conditions of iron overload.
Mechanism of activation of hepatic stellate cells in Biliary Atresia
We have shown that hepatic stellate cells cause the cirrhosis which is
characteristic in the congenital bile duct obstructive disease, biliary
atresia (Ramm et al, 1998). However, the mechanisms responsible for hepatic
stellate cell activation in this condition are not known. Our group leads
a multi-centre collaborative project with Dr Darrell Crawford from the
Princess Alexandra Hospital, and Dr Peter Lewindon and Prof Ross Shepherd
from the Royal Children's Hospital. This project focuses on the mechanisms
whereby bile duct epithelial cells are induced to release the profibrogenic
cytokine transforming growth factor-beta (Ramm et al, 1998) which stimulates
collagen production and cirrhosis. Further investigations will evaluate
the potential aetiology of the fibrotic, obstructive bile duct disease
in these children and evaluate the potential for chemoattraction of hepatic
stellate cells and inflammatory cells to the site of injury surrounding
the bile ducts.
Role of hepatic stellate cells in the focal biliary cirrhosis in
Cystic Fibrosis liver disease
This is a collaborative project with Dr Peter Lewindon and Prof Ross Shepherd
from the Royal Children's Hospital and Dr Jeffery Smith from The University
of Queensland Department of Surgery. This study is designed to assess
a number of serum markers of fibrosis for detecting early fibrogenesis,
and the severity and progression of liver injury in children with cystic
fibrosis liver disease. The study also utilises the isolated hepatic stellate
cell to evaluate the potential mechanisms whereby these cells are activated
to produce excess collagen leading to the focal biliary cirrhosis which
characterises cystic fibrosis liver disease. Finally we are using cDNA
array analysis to examine the expression of a number of known genes in
the disease process and plan to investigate potential novel genes which
may be involved in the fibrogenesis which leads to focal biliary cirrhosis
in cystic fibrosis liver disease.
Staff
| Labhead and NHMRC Senior Research Fellow: | Associate Professor Grant A. Ramm |
| Research Officers: | Dr Richard Ruddell Dr Tamara Pereira Dr Marie Bertrand Dr Meagan Walsh |
| Research Assistant: | Mrs Louise Ramm Mr Darryn Rowsell |
| PhD scholars: | Dr Marnie Wood Mr Peng Cheng Li Mrs Lynne Reid |
| Visiting Scientists: |
Dr Peter Lewindon Dr Graeme Macdonald Dr Jeffery Smith |
To see staff contact details, please type name below and hit Enter
Funding
NHMRC Program Grant (2005-2009)on Iron and Liver Disease
Role of iron biology in hepatic stellate cell activation in haemochromatosis.
NHMRC Program Grant (2008-2010)on
Role of Chemoattractants in
hepatic stellate recruitment and fibrogenesis in Paediatric Cholestatic Liver Disease.
Collaborators
Dr Peter Lewindon, Department of Gastroenterology, Royal Children's Hospital,
Brisbane
Dr Darrell Crawford, Department of Gastroenterology, Princess Alexandra
Hospital, Brisbane
Dr Graeme Macdonald, Department of Medicine, Royal Brisbane Hospital,
Brisbane
Dr Gregory Anderson, Iron Metabolism Laboratory, QIMR.
Dr Nathan Subramaniam, Cell Membrane Transport Laboratory, QIMR.
Assoc. Prof. John Olynyk, Department of Medicine, Fremantle Hospital,
Fremantle
Prof. Tom Tracy, Department of Paediatric Surgery, Brown University, Rhode
Island, USA
Prof. Bruce Bacon, Department of Internal Medicine, St Louise University,
St Louis, USA
Prof Paulo Arosio, University of Brescia, Brescia, ITALY
Prof Ross Shepherd, Washington University, St Louis, USA

Dr Peter Lewindon (Royal Children's Hospital - left)
and Dr Grant Ramm (QIMR - right) with patient Lauren Hockey
Key Publications
Harty MW, Papa EF, Huddleston HM, Young E, Nazareth S, Riley CA, RAMM GA, Gregory SH, Tracy TF, Jr, (2008). Hepatic macrophages promote the neutrophil-dependent resolution of fibrosis in repairing cholestatic rat livers. Surgery, 143(5): 667-678 [pubmed abstract]Olynyk JK, Trinder D, RAMM GA, Britton RS and Bacon BR, (2008). Hereditary hemochromatosis: Recent developments. Hepatology, (in press).
Wood M, Powell LW and RAMM GA, (2008). Environmental and genetic modifiers of the progression to fibrosis and cirrhosis in hemochromatosis. Blood, 111(9):4456-4462.[pubmed abstract]
Ruddell RG, Mann DA and RAMM GA, (2008). The function of serotonin within the liver. J. Hepatol., 48(4):666-675. [pubmed abstract]
Milward E, Johnstone D, Trinder D, RAMM G and Olynyk J, (2007). The nexus of iron and inflammation in hepcidin regulation: SMADs, STATs and ECSIT. Hepatology, 45(1):253-256. [pubmed abstract]
Philippe MA, Ruddell RG and RAMM GA, (2007). The role of iron in hepatic fibrosis: Another piece in the puzzle. World J. Gastroenterol., 13(35):4746-4754. [pubmed abstract]
Knight B, Akhurst B, Matthews VB, Ruddell RG, RAMM GA, Abraham LJ, Olynyk JK and Yeoh GC, (2007). Attenuated liver progenitor (oval) cell and fibrogenic responses to the choline deficient, ethionine supplemented diet in the BALB/c inbred strain of mice. J. Hepatol., 46(1):134-141. [pubmed abstract]
Wallace DF, Dixon JL, RAMM GA, Anderson GJ, Powell LW and Subramaniam VN, (2007). A novel mutation in ferroportin implicated in iron overload. J. Hepatol., 46(5):921-926.[pubmed abstract]
Kobayashi Y, Bridle KR, RAMM GA, O'Neill R, Britton RS and Bacon BR, (2007). Effect of phorbol esters and platelet-derived growth factor on protein kinase C in rat hepatic stellate cells. Liver Int., 27(8):1066-1075. [pubmed abstract]
Shteyer E, RAMM GA, Xu C, White FV and Shepherd RW, (2006). Outcome after Portoenterostomy in Biliary Atresia: Pivotal Role of Degree of Liver Fibrosis and Intensity of Stellate Cell Activation. J. Pediatr. Gastr. Nutr., 42(1):93-99. [pubmed abstract]
Powell LW, Dixon JL, RAMM GA, Purdie DM, Lincoln DJ, Anderson GJ, Subramaniam VN, Hewett DG, Searle JW, Fletcher LM, Crawford DH, Rodgers H, Allen KJ, Cavanaugh JA and Bassett ML, (2006). Screening for hemochromatosis in asymptomatic subjects with or without a family history. Arch. Intern. Med., 166:294-301. * These authors contributed equally to this paper - Equal FIRST Authors. [pubmed abstract]
Ruddell RG, Oakley F, Hussain Z, Yeung I, Bryan-Lluka LJ, RAMM GA and Mann DA, (2006). A role for serotonin (5-HT) in hepatic stellate cell function and liver fibrosis. Am. J. Pathol., 169(3):861-876.[pubmed abstract]
Arnold JM, Huggard PR, Pandeya N, Cummings M, Purdie DM, RAMM GA and Chenevix-Trench G, (2005). Monocyte Chemoattractant Protein-1 (MCP-1) expression is reduced in ovarian adenocarcinoma and re-expression suppresses in vitro growth and soft agar clonicity. Brit. J. Cancer, 92(11):2024 31.[pubmed abstract]
Harty MW, Huddleston HM, Papa EF, Puthawala T, Tracy AP, RAMM GA, Gehring S, Gregory SH, and Tracy TF, Jnr., (2005), Repair after cholestatic liver injury correlates with neutrophil infiltration and matrix metalloproteinase 8 activity. Surgery, 138(2):313-20. [pubmed abstract] RAMM GA and Ruddell RG, (2005). Hepatotoxicity of iron overload: Mechanisms of iron-induced hepatic fibrogenesis. Semin. Liver Dis., 25(4):433-449.[pubmed abstract]
Milward EA, Trinder D, Wilcox CEJ, Britton RS, RAMM GA and Olynyk JK, (2005). Is HFE involved in increased
hepcidin expression and hypoferremia in inflammation and anemia of chronic disease? Hepatology. 41(4):936-938.
[pubmed abstract]
Smith JL, Lewindon PJ, Hoskins AC, Pereira TN, Setchell KDR, O'Connell NC, Shepherd RW and RAMM GA, (2004).
Endogenous ursodeoxycholic acid and cholic acid in liver disease due to cystic fibrosis.
Hepatology. 39:1673-1682.
[pubmed abstract]
Apte MV, Park S, Phillips PA, Santucci N, Goldstein D, Kumar RK, RAMM GA, Buchler M, Friess H, McCarroll JA, Keogh G,
Merrett N, Pirola R and Wilson JS, (2004). Desmoplastic reaction in pancreatic cancer: role of pancreatic stellate
cells. Pancreas. 29(3):179-187.
[pubmed abstract]
Pereira TN, Lewindon PJ, Smith JL, Murphy TL, Lincoln DJ, Shepherd RW and RAMM GA, (2004). Serum markers of hepatic
fibrogenesis in cystic fibrosis liver disease. J. Hepatol. 41(4):576-583.
[pubmed abstract]
RAMM GA, Hoskins AC, Greco SA, Pereira TN and Lewindon PJ, (2004). Signals for hepatic fibrogenesis in pediatric
cholestatic liver disease: Review and hypothesis. Comp. Hepatol. 3;(Suppl.1):S5(1-5).
[pubmed abstract]
Anderson GJ, Frazer DM, Bridle KR, Subramaniam VN, Crawford DHG, Powell LW and RAMM GA, (2004). Hepcidin in HFE-associated hemochromatosis: anotherpiece of the "iron" puzzle - Reply. Gastroenterology. 126(2):616.
Bridle KR, Frazer DM, Wilkins SJ, Dixon JL, Purdie DM, Crawford DHG, Subramaniam VN, Powell LW, Anderson GJ and RAMM
GA, (2003). Disrupted hepcidin upregulation in HFE-associated hemochromatosis and liver as a regulator of body iron
homeostasis. The Lancet. 361:669-73.
[pubmed abstract]
Bridle KR, Crawford DHG, Fletcher LM, Smith JL, Powell LW and RAMM GA, (2003). Evidence for a sub-morphological
inflammatory process in the liver in haemochromatosis. J. Hepatol. 38(4):425-432.
[pubmed abstract]
RAMM GA, Li L, Britton RS, O'Neill R, and Bacon BR, (2003). Effect of protein kinase C activation and inhibition
on rat hepatic stellate cell activation . Dig. Dis. Sci. 48(4):790-796.
[pubmed abstract]
Bridle KR, Crawford DHG and RAMM GA, (2003). Identification and characterization of the hepatic stellate cell
transferrin receptor. Am. J. Pathol. 162:1661-1667.
[pubmed abstract]
Lewindon PJ, Pereira TN, Hoskins AC, Williamson RM, Bridle KR, Shepherd RW and RAMM GA, (2002). The role of hepatic
stellate cells and transforming growth factor-b1 in cystic fibrosis liver disease. Am. J. Pathol. 160(5):1705-1715.
[pubmed abstract]
Olynyk JK, Khan NA, RAMM GA, Brown KE, O'Neill R, Britton RS and Bacon BR, (2002). Aldehydic products of lipid
peroxidation do not directly activate rat hepatic stellate cells. J. Gastroenterol. Hepatol. 17(7):785-790.
[pubmed abstract]
Bridle KR, Crawford DHG, Powell LW and Ramm GA, (2001). Role of myofibroblasts in tumour encapsulation of
hepatocellular carcinoma in haemochromatosis. Liver, 21(2):96-104. [pubmed abstract]
Young J, Biden KG, Simms LA, Huggard PR, Karamatic R, Eyre HJ, Sutherland
GR, Herath N, Barker M, Anderson GJ, Fitzpatrick D, Ramm GA, Jass JR and
Leggett BA, (2001). HPP1: a transmembrane protein-encoding gene commonly methylated in colorectal polyps and cancers.
Proc. Natl. Acad. Sci. USA.,
98(1):265-270. [pubmed abstract]
Macdonald GA, Bridle KR, Ward PJ, Walker NI, Houglum K, George DK, Smith JL, Powell LW,
Crawford DHG and RAMM GA, (2001). Lipid peroxidation in hepatic steatosis in humans is associated
with hepatic fibrosis and occurs predominantly in acinar zone 3. J. Gastroenterol. Hepatol. 16(6):599-606.
[pubmed abstract]
Neuschwander-Tetri BA, Bridle KR, Wells LD, Marcu M and Ramm GA, (2000).
Repetitive acute pancreatic injury in the mouse induces procollagen alpha1
(I) mRNA expression colocalized to pancreatic stellate cells. Lab.
Invest., 80(2):143-50. [pubmed abstract]
Ramm GA, Carr SC, Bridle KR, Li L, Crawford DHG, Vogler CA, Britton RS,
Bacon BR and Tracy TF, Jr, (2000). The morphology of liver repair following
cholestatic liver injury: resolution of ductal hyperplasia, matrix deposition
and regression of myofibroblasts. Liver, 20(5):387-396.
[pubmed abstract]
Haber PS, Keogh GW, Apte MV, Moran CS, Stewart NL, Crawford DHG, Pirola
RC, McCaughan GW, Ramm GA and Wilson JS, (1999). Activation of pancreatic
stellate cells in human and experimental pancreatic fibrosis. Am. J.
Pathol., 155:1087-1095. [pubmed abstract]
George DK, Ramm GA, Walker NI, Powell LW and Crawford DHG, (1999). Elevated
serum type IV collagen: a sensitive indicator of the presence of cirrhosis
in haemochromatosis. J. Hepatol., 31(1):47-52. [pubmed abstract]
Ramm GA, Nair VG, Bridle KR, Shepherd RW and Crawford DHG, (1998). Contribution
of hepatic parenchymal and non-parenchymal cells to hepatic fibrogenesis
in biliary atresia. Am. J. Pathol., 153(2):527-535. [pubmed
abstract]
Ooi LLPJ, Crawford DHG, Gotley DC, Clouston AD, Strong RW, Gobé GC, Halliday
JW, Bridle KR and Ramm GA, (1997). Evidence that "myofibroblast-like"
cells are the cellular source of capsular collagen in hepatocellular carcinoma.
J. Hepatol., 26(4):798-807. [pubmed abstract]
RAMM GA, (1998). Isolation and culture of rat hepatic stellate cells.
J.Gastroenterol. Hepatol. 13:845-850.
[pubmed abstract]
Houglum K, Ramm GA, Crawford DHG, Witztum J, Powell LW and Chojkier M,
(1997). Excess iron induces hepatic oxidative stress and transforming growth factor beta1 in genetic hemochromatosis.
Hepatology, 27:605-610.
[pubmed abstract]
Ramm GA, Britton RS, O'Neill R, Kohn HD and Bacon BR, (1996). Rat liver
ferritin selectively inhibits the expression of alpha-smooth muscle actin
in cultured rat lipocytes. Am. J. Physiol., 270:G370-G375.
[pubmed abstract]
Ramm GA, Britton RS, O'Neill R and Bacon BR, (1994). Identification and
characterization of a receptor for tissue ferritin on activated rat lipocytes.
J. Clin. Invest., 94:9-15. [pubmed abstract]



