Regulated and reversible induction of adult human β-cell replication.
Induction of proliferation in adult human β-cells is challenging. It can be accomplished by introduction of cell cycle molecules such as cyclin-dependent kinase 6 (cdk6) and cyclin D1, but their continuous overexpression raises oncogenic concerns. We attempted to mimic normal, transient, perinatal human β-cell proliferation by delivering these molecules in a regulated and reversible manner. Adult cadaveric islets were transduced with doxycycline (Dox)-inducible adenoviruses expressing cdk6 or cyclin D1. End points were cdk6/cyclin D1 expression and human β-cell proliferation, survival, and function. Increasing doses of Dox led to marked dose- and time-related increases in cdk6 and cyclin D1, accompanied by a 20-fold increase in β-cell proliferation. Notably, Dox withdrawal resulted in a reversal of both cdk6 and cyclin D1 expression as well as β-cell proliferation. Re-exposure to Dox reinduced both cdk/cyclin expression and proliferation. β-Cell function and survival were not adversely affected. The adenoviral tetracycline (tet)-on system has not been used previously to drive human β-cell proliferation. Human β-cells can be induced to proliferate or arrest in a regulated, reversible manner, temporally and quantitatively mimicking the transient perinatal physiological proliferation that occurs in human β-cells.
University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA. takane@pitt.edu
Karen K
KK
Takane
Jeffery W
JW
Kleinberger
Fatimah G
FG
Salim
Nathalie M
NM
Fiaschi-Taesch
Andrew F
AF
Stewart
D000256:Adenoviridae / Q000235:genetics; D000328:Adult; D049109:Cell Proliferation / Q000187:drug effects; D019938:Cyclin D1 / Q000235:genetics / Q000502:physiology; D051361:Cyclin-Dependent Kinase 6 / Q000235:genetics / Q000502:physiology; D004318:Doxycycline / Q000494:pharmacology; D006801:Humans; D050417:Insulin-Secreting Cells / Q000502:physiology*
C530104:CCND1 protein, human; D019938:Cyclin D1; C495911:CDK6 protein, human; D051361:Cyclin-Dependent Kinase 6; D004318:Doxycycline