beta-Cell specific cytoprotection by prolactin on human islets.
BACKGROUND
Many cytoprotective agents have been reported to improve islet isolation and transplantation outcomes. However, several of these agents improve all cell subsets within an islet preparation; selection of non-beta-cell components (eg, acinar cells) may have a negative effect on beta-cell function and survival. In this study, we examined the effect of prolactin (PRL) supplementation in the culture medium to determine whether it exerted beta-cell-selective cytoprotection on islet viability and function.


METHODS
Human islets were precultured with or without recombinant human PRL (500 microg/L) for 48 hours. The fractional viability and cellular composition of non-beta-cell and beta-cell-specific components were assessed using FACS and Laser Scanning Cytometry (LSC). Islet potency was assessed in vivo by transplantation into chemically induced diabetic immunodeficient mice.


RESULTS
The relative viable beta-cell mass and the relative islet beta-cell content in the PRL group were 28% higher (P = .018) and 19% higher (P = .029) than the control group, respectively. All transplanted mice achieved normoglycemia in both groups, indicating that PRL treatment did not alter islet function.


CONCLUSIONS
PRL treatment improved beta-cell-specific viability and survival of human islets in vitro. The development of novel beta-cell-specific cytoprotective strategies may be of assistance in improving islet transplantation.
Yamamoto
T
T
Diabetes Research Institute, University of Miami, Leonard M. Miller School of Medicine, Miami, Florida 33136, USA.
Ricordi
C
C
Mita
A
A
Miki
A
A
Sakuma
Y
Y
Molano
R D
RD
Fornoni
A
A
Pileggi
A
A
Inverardi
L
L
Ichii
H
H
D000818:Animals; D018929:Cell Culture Techniques; D002470:Cell Survival / Q000187:drug effects*; D003921:Diabetes Mellitus, Experimental / Q000601:surgery*; D004195:Disease Models, Animal; D006801:Humans; D050417:Insulin-Secreting Cells / Q000166:cytology* / Q000187:drug effects / Q000637:transplantation; D016381:Islets of Langerhans Transplantation; D051379:Mice; D008819:Mice, Nude; D011388:Prolactin / Q000494:pharmacology*
D011388:Prolactin