Copper Homeostasis and Liver Function

PROJECT SUMMARY Wilson disease (WD) is a potentially fatal metabolic disorder caused by genetic mutations in the copper (Cu) transporter ATP7B and Cu accumulation in tissues. Despite significant progress in identification of disease- causing mutations, WD remains challenging to diagnose and treat. Using new experimental models and protocols, this project will develop a comprehensive model of WD pathogenesis and identify new targets for treatment. Specific Aim 1 will generate an integrated picture of multi-cellular Atp7b-/- liver response to Cu overload in WD using single cell sequencing data, immunostaining, and qPCR studies. The role of metallothioneins in disease onset and progression will be examined, and sex-specific differences in metabolic status of the WD liver will be characterized. The results will be used to identify unique characteristics of hepatic WD when compared to phenotypically overlapping liver diseases. In Specific Aim 2, the new mouse strain, Atp7bMac, with Atp7b deleted in cells of myeloid origin, will be characterized and further employed to determine the role of Atp7b in functional maturation of neutrophils. The functional consequences of Atp7b loss in myeloid cells will be determined following LPS injection and evaluation of immune response. Specific Aim 3 will elucidate the liver-gut interaction in WD. By using in situ secretory protein labeling via ER-anchored TurboID, we will compare liver secretomes of control, Atp7bMac mice and mice with a targeted deletion of Atp7b in hepatocytes (Atp7bHep mice) to determine how liver signaling is altered by Cu misbalance in the gut and in NPLC.