title: Biomarker system for studying muscle, stem cells, and cancer in vivo.
abstract: Bioluminescent reporter genes are sensitive in situ tools for following disease progression in preclinical models, albeit they are subject to scattering and absorption in deep tissues. We have generated a bicistronic Cre/LoxP reporter mouse line that pairs the expression of firefly luciferase with quantifiable expression of a human placental alkaline phosphatase that is secreted into the serum (SeAP). With the use of this dual-modality bioreporter with a novel, inducible Pax7-CreER line for tracking muscle satellite cells, we demonstrate the longitudinal kinetics of muscle stem cell turnover, accounting for a doubling of the signal from satellite cell and progeny every 3.93 wk in the transition from adolescence to early adulthood. We also show that this dual-modality bioreporter can be incorporated in preclinical cancer models, whereby SeAP activity is reflective of tumor burden. Thus, this dual bioreporter permits both spatial localization and accurate quantification of biological processes in vivo even when the tissue of interest is deep within the animal.
authors.affiliation: Greehey Children's Cancer Research Institute and Department of Cellular and Structural Biology, University of Texas Health Science Center, San Antonio, Texas, USA.
authors.forename: Koichi
authors.initials: K
authors.lastname: Nishijo
authors.forename: Tohru
authors.initials: T
authors.lastname: Hosoyama
authors.forename: Christopher R R
authors.initials: CR
authors.lastname: Bjornson
authors.forename: Beverly S
authors.initials: BS
authors.lastname: Schaffer
authors.forename: Suresh I
authors.initials: SI
authors.lastname: Prajapati
authors.forename: Ali N
authors.initials: AN
authors.lastname: Bahadur
authors.forename: Mark S
authors.initials: MS
authors.lastname: Hansen
authors.forename: Mary C
authors.initials: MC
authors.lastname: Blandford
authors.forename: Amanda T
authors.initials: AT
authors.lastname: McCleish
authors.forename: Brian P
authors.initials: BP
authors.lastname: Rubin
authors.forename: Jonathan A
authors.initials: JA
authors.lastname: Epstein
authors.forename: Thomas A
authors.initials: TA
authors.lastname: Rando
authors.forename: Mario R
authors.initials: MR
authors.lastname: Capecchi
authors.forename: Charles
authors.initials: C
authors.lastname: Keller