Ductular reaction predicts the progression of non-alcoholic
fatty liver disease
Ramy Younes1,2, Stuart McPherson1,3, Elisabetta Bugianesi2, Quentin M
Anstee1,3, Dina Tiniakos1,4* & Olivier Govaere1*
*Contributed equally
1Institute of Cellular Medicine, Newcastle University, Newcastle upon Tyne, United Kingdom. 2Department of Medical Sciences, Division of Gastro-Hepatology, A.O. Città della Salute e
della Scienza di Torino, University of Turin, Turin, Italy
3Liver Unit, Freeman Hospital, Newcastle upon Tyne Hospitals NHS Foundation Trust, UK 4Dept of Pathology, Aretaieio Hospital, National & Kapodistrian University of Athens, Greece
Introduction: Ductular reaction (DR), which comprises an expansion of
transit amplifying cells of the terminal branches of the biliary tree, is often seen in advanced NAFLD and is believed to reflect hepatic progenitor cell (HPC) activation.
Aim: This study aims to investigate the prognostic value of DR/HPCs in
NAFLD for NASH development and fibrosis progression.
Methods: We included 36 patients with biopsy-proven NAFLD at Freeman
Hospital, Newcastle-Upon-Tyne Hospitals, UK, who underwent at least two liver biopsies more than a year apart. The histological semi-quantitative NAS CRN system was used to score steatosis (S0–3), ballooning (B0-2), lobular inflammation (I0–3) and to stage fibrosis (F0–4). HPCs were quantified in the portal/periportal area and parenchyma based on Keratin 19 immunostaining in the baseline biopsies and correlated with clinicopathological features. Parenchymal ductular cells were scored based on acinar zone topography (1-3) and pattern (single cells, ductular structures)
Results: In our cohort, the absolute number of periportal HPCs significantly
correlated with elevated AST levels (p<0.01). Moreover, the presence of HPCs into the parenchyma correlated with higher AST (p<0.01), ALT (p<0.05) and with the progressive increase of insulin levels (p<0.01). The small sample size of the cohort did not allow us to highlight a significant association between the absolute number of either periportal or parenchymal HPCs and fibrosis progression or the occurrence of NASH, although a positive trend was reported. Comparing baseline and follow-up liver biopsies (mean time
between biopsies 79 months, range 14-198), the presence of ductular structures in the parenchyma of the baseline biopsy was significantly associated with the progression of at least 1 stage of fibrosis (prevalence of 35% in progressors vs 6% in non-progressors, p<0.05). In addition, a significant correlation with the increase of AST and ALT levels was noted (OR 1.028 and 1.026 respectively).
Conclusions: In a cohort of biopsy-proven NAFLD patients with follow-up
biopsies, HPCs are associated with biochemical signs of inflammation and higher insulin levels. Moreover, the presence of parenchymal ductular structures predicts disease progression. Due to the lack of a prognostic biomarker for NAFLD, the development of this tool could acquire paramount importance for both stratifying patients at risk at baseline and the design of targeted therapies to patients with high likelihood of disease progression.
