title: An integrase facilitates long-lasting foreign gene expression in vivo in mouse spermatogenic cells.
abstract: The objective of the present study was to attain long-lasting foreign gene expression in vivo in spermatogenic cells in the mouse testis for establishing spermatogenic-cell mediated gene transformation. Prior to in vivo gene transfer, surgical cryptorchidism was performed by retaining the testis into the abdominal cavity for 1 month to remove differentiated spermatogenic cells. Subsequently, in vivo gene transfer was conducted by electroporation with a lacZ reporter gene in combination with a retroviral integrase gene, and the testis was descended immediately to the scrotum to recover from the cryptorchidism, and restart spermatogenesis. At 1 month post-transfection in vivo, lacZ gene expression was detected in some spermatocyte-like cells in seminiferous tubules of the mouse testis. However, the recovery period of 1 month appeared to be too short, since no elongated and fully differentiated spermatids were found. At 2 months post-transfection, fully differentiated spermatogenic cells expressing the lacZ gene, albeit at low frequency, were detected when the integrase gene was co-transfected, while virtually no lacZ-positive cells were found in the absence of the integrase gene. It was concluded, therefore, that stable transformation of spermatogenic cells in vivo would be facilitated by integrase gene co-transfection.
authors.affiliation: Department of Applied Molecular Biosciences, Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya 464-8601, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Ryoki
authors.forename: H
authors.initials: H
authors.lastname: Park
authors.forename: Y
authors.initials: Y
authors.lastname: Ohmori
authors.forename: A
authors.initials: A
authors.lastname: Shoji-Tanaka
authors.forename: T
authors.initials: T
authors.lastname: Muramatsu