Prolactin supplementation to culture medium improves beta-cell survival.
OBJECTIVE
Recent studies demonstrated that prolactin (PRL) has beneficial effects on beta cells for islet transplantation. We examined the effect of human recombinant PRL (rhPRL) supplementation to the culture media to determine its potential use in the context of clinical islet transplantation.


METHODS
Each human islet isolated from 14 deceased multiorgan donors was cultured in Miami modified media-1 supplemented with or without rhPRL (500 microg/L) for 48 hr. beta-Cell survival and proliferation (BrdU and Ki-67) were determined by laser scanning cytometry. The cytoprotective effects of rhPRL against noxious stimuli were assessed by flow cytometry (tetramethylrhodamine ethyl ester). Cytokine/chemokine and tissue factor productions were measured in vitro, and islet potency was assessed in vivo in diabetic immunodeficient mice.


RESULTS
beta-Cell survival during culture was 37% higher in the rhPRL group than in control (P=0.029). rhPRL protected beta cells in vitro from cytokines, Nitric oxide donor, and H2O2. The exposure to rhPRL did not affect human beta-cell proliferation with our protocol. rhPRL treatment did not alter cytokine/chemokine and tissue factor production in vitro or affected human islet functionality in vivo: recipient mice achieved normoglycemia with a comparable tempo, whereas loss of graft function was observed in two of the seven mice in the control group and in none of the rhPRL group (p=n.s.).


CONCLUSIONS
rhPRL supplementation to islet culture media improved human beta-cell-specific survival without altering islet quality. Addition of rhPRL to cultured islets may grant a more viable beta-cell mass in culture. The development of beta-cell cytoprotective strategies will be of assistance in improving islet transplantation outcomes.
Yamamoto
Toshiyuki
T
Cell Transplant Center, Diabetes Research Institute, University of Miami Leonard M. Miller School of Medicine, Miami, FL, USA.
Mita
Atsuyoshi
A
Ricordi
Camillo
C
Messinger
Shari
S
Miki
Atsushi
A
Sakuma
Yasunaru
Y
Timoneri
Francesca
F
Barker
Scott
S
Fornoni
Alessia
A
Molano
R Damaris
RD
Inverardi
Luca
L
Pileggi
Antonello
A
Ichii
Hirohito
H
D000241:Adenosine; D000493:Allopurinol; D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D002102:Cadaver; D018929:Cell Culture Techniques / Q000379:methods; D002455:Cell Division / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D018925:Chemokines / Q000096:biosynthesis; D003470:Culture Media; D016207:Cytokines / Q000096:biosynthesis; D005978:Glutathione; D006801:Humans; D007328:Insulin; D050417:Insulin-Secreting Cells / Q000166:cytology* / Q000187:drug effects; D016381:Islets of Langerhans Transplantation / Q000379:methods / Q000502:physiology; D051379:Mice; D019188:Organ Preservation Solutions; D011388:Prolactin / Q000494:pharmacology*; D011887:Raffinose; D011994:Recombinant Proteins / Q000494:pharmacology; D014019:Tissue Donors; D014183:Transplantation, Heterologous / Q000502:physiology
D018925:Chemokines; D003470:Culture Media; D016207:Cytokines; D007328:Insulin; D019188:Organ Preservation Solutions; D011994:Recombinant Proteins; C055206:University of Wisconsin-lactobionate solution; D000493:Allopurinol; D011388:Prolactin; D005978:Glutathione; D000241:Adenosine; D011887:Raffinose