Enhanced maturation of porcine neonatal pancreatic cell clusters with growth factors fails to improve transplantation outcome.
BACKGROUND
Porcine neonatal pancreatic cell clusters (NPCC) are a potential source of islet tissue for clinical transplantation. They can normalize glycemia after transplantation, although after a relatively long (several weeks) period of time, possibly due to the immaturity of the tissue.


METHODS
One week after isolation NPCCs were immobilized in alginate hydrogel to be cultured for 2 more weeks in the presence of different growth factors, which were applied individually or in various combinations. Their effect was assessed by measuring DNA and insulin content, and expression of islet genes by reverse transcriptase-polymerase chain reaction. Enhanced maturation of NPCCs was also evaluated after transplantation in streptozotocin-diabetic mice.


RESULTS
A combination of fetal calf serum, insulin-like growth factor-I, nicotinamide and sodium butyrate in NPCCs media from day 7 to day 21 resulted in increased insulin/DNA content and higher expression of insulin, somatostatin, GLUT2 and Nkx6.1 genes. NPCCs cultured under the same conditions from day 3 to day 12 were transplanted into diabetic mice. Control mice were transplanted with NPCCs cultured in parallel in the presence of nicotinamide, but with no serum, insulin-like growth factor-I or butyrate. Normoglycemia was achieved at the same rate in both groups. Plasma porcine C-peptide (week 6) and graft insulin content (week 20) were also similar in both groups.


CONCLUSIONS
Increased insulin content of NPCCs was achieved in vitro by addition of fetal calf serum, insulin-like growth factor-I, nicotinamide, and sodium butyrate, but this increase did not translate into a faster achievement of normoglycemia after transplantation, which suggests that there is a time frame required for complete maturation that is difficult to alter.
Lopez-Avalos
M D
MD
Research Division, Joslin Diabetes Center, Boston, MA 02215, USA.
Tatarkiewicz
K
K
Sharma
A
A
Bonner-Weir
S
S
Weir
G C
GC
D000818:Animals; D000831:Animals, Newborn; D001786:Blood Glucose / Q000378:metabolism; D002096:C-Peptide / Q000097:blood; D002417:Cattle; D018929:Cell Culture Techniques / Q000379:methods; D003470:Culture Media; D003921:Diabetes Mellitus, Experimental / Q000097:blood / Q000601:surgery*; D005786:Gene Expression Regulation; D005934:Glucagon / Q000235:genetics; D005941:Glucokinase / Q000235:genetics; D051273:Glucose Transporter Type 2; D006133:Growth Substances / Q000494:pharmacology*; D006801:Humans; D007328:Insulin / Q000032:analysis / Q000235:genetics; D007334:Insulin-Like Growth Factor I / Q000494:pharmacology; D007515:Islets of Langerhans / Q000166:cytology* / Q000187:drug effects / Q000502:physiology; D016381:Islets of Langerhans Transplantation / Q000502:physiology*; D009004:Monosaccharide Transport Proteins / Q000235:genetics; D009536:Niacinamide / Q000494:pharmacology; D010179:Pancreas / Q000166:cytology*; D016133:Polymerase Chain Reaction; D011994:Recombinant Proteins / Q000494:pharmacology; D013004:Somatostatin / Q000235:genetics; D013552:Swine; D016896:Treatment Outcome
D001786:Blood Glucose; D002096:C-Peptide; D003470:Culture Media; D051273:Glucose Transporter Type 2; D006133:Growth Substances; D007328:Insulin; D009004:Monosaccharide Transport Proteins; D011994:Recombinant Proteins; D009536:Niacinamide; D013004:Somatostatin; D007334:Insulin-Like Growth Factor I; D005934:Glucagon; D005941:Glucokinase