Dr. Liu's research is focused on stem cell biology in the airway, and lung gene therapy for cystic fibrosis (CF). Projects related to airway stem cell biology include defining molecular pathways that regulate the formation of proximal airway stem cell niches, and determining how these signals control the mobilization of stem cells from their niches following airway injury. The goals of these studies are to better understand the fates of submucosal gland stem cells in the airway during the pathogenesis of hypersecretory lung diseases such as CF, and to develop gene therapy approaches using viral vectors to target stem cells in the adult airway. In this regard, Dr. Liu has developed novel strategies to correct CFTR defects at the mRNA level, using Spliceosome-Mediated RNA Trans-splicing. He is currently evaluating the utility of this approach in stem cell-directed therapies, applied both to the adult mouse airway and to humanized airway xenograft models. Dr. Liu has pioneered studies designed to identify the species-specific differences in airway epithelial biology and AAV transduction ? between pig, ferret, mouse, non-human primate, and human ? that are important for modeling gene therapies for CF.
Selected Publications:
Liu X, Luo M, Yan Z, Guo C, Wang Y and Engelhardt JF,, 2007. Species-specific rAAV Transduction in Polarized Ferret and Pig Airway Epithelia, Gene Therapy, 14(21): 1543-1548.
Liu X, Luo M, Yan Z, Lei-Butters D, Trygg C, Bunnell B and Engelhardt JF, 2007. Biological Differences in rAAV Transduction of Human and Old World Non-Human Primate Airway Epithelia. Molecular Therapy, 15(12): 2114-2123.
Liu X, Luo M, Zhang L, Ding W, Yan Z, Engelhardt JF, 2007. Bioelectric Properties of Chloride Channels in Human, Pig, Ferret and Mouse Airway Epithelia, Am J Respiratory Cell Mol Biol. 36(3): 313-323.
Liu X, Yan Z, Luo M, Engelhardt JF, 2006. Species-specific difference in mouse and human airway epithelial biology of rAAV transduction, Am Journal of Respiratory Cell and Molecular Biology, 34(1): 56-64.