PII-027 - LEVERAGING MACHINE LEARNING (ML) TO QUANTIFY CHANGES IN CELLULAR LOCALIZATION AND ZONAL DISTRIBUTION OF TRANSPORTERS IN LIVER TISSUE FROM PATIENTS WITH NONALCOHOLIC FATTY LIVER DISEASE (NAFLD).

W. Murphy¹, D. Fu¹, A. Diehl², M. Abdelmalek³, N. Sjöstedt⁴, S. Neuhoff⁵, P. Honkakoski⁶, K. Brouwer¹; ¹University of North Carolina at Chapel Hill, Chapel Hill, NC, USA, ²Duke University Medical Center, Durham, NC, USA, ³Mayo Clinic, Rochester, MN, USA, ⁴University of Helsinki, Helsinki, Finland, ⁵Certara UK Ltd. (Simcyp division), Sheffield, United Kingdom, ⁶University of Eastern Finland, Kuopio, Finland.

Background: Recent qualitative data suggest that not all hepatic transporters are properly localized to the plasma membrane (PM), particularly in NAFLD1,2, while changes in transporter zonal expression in NAFLD are currently unknown3. To address these knowledge gaps, we developed a framework that utilizes ML 3D image analysis to derive quantitative cellular localization and zonal distribution data suitable for scaling within physiologically based pharmacokinetic (PBPK) models.

Methods: Human liver [control; nonalcoholic fatty liver (NAFL); nonalcoholic steatohepatitis (NASH)] biopsies were fluorescently stained for BSEP, NTCP, or OATP1B1/1B3 and a basolateral (Na+/K+-ATPase) or canalicular (CD-13) PM marker, and then imaged by confocal microscopy. Imaris ML classifier and Labkit pixel classification were used for transporter and PM marker surface rendering, respectively. The percentage (%) volume overlap of each transporter with the PM marker and zonal expression were calculated and are presented in Table 1.

Results: Significant differences in BSEP and OATP1B1 zonality and a trend towards decreased BSEP and NTCP PM localization were observed in NAFLD.

Conclusion: This innovative approach framework provides new information on changes of localization and zonation of hepatic drug transporters in NAFLD that can be directly applied to PBPK models.

1.    Hardwick, R. N., Fisher, C. D., Canet, M. J., Scheffer, G. L. & Cherrington, N. J. Variations in ATP-binding cassette transporter regulation during the progression of human nonalcoholic fatty liver disease. Drug Metab. Dispos. 39, 2395–2402 (2011).
2.    Canet, M. J. et al. Altered regulation of hepatic efflux transporters disrupts acetaminophen disposition in pediatric nonalcoholic steatohepatitis. Drug Metab. Dispos. 43, 829–835 (2015).
3.    Ölander, M. et al. Hepatocyte size fractionation allows dissection of human liver zonation. J. Cell. Physiol. 236, 5885–5894 (2021).

Table 1. Plasma membrane (PM) localization and zonal expression data for transporters of interest.