Mesenchymal stem cells contribute to insulin-producing cells upon microenvironmental manipulation in vitro.
BACKGROUND
Extracellular microenvironment and intrinsic genetic programs determine the fate of stem cells. We observed whether mesenchymal stem cells (MSCs) contributed to insulin-producing cells in a manipulated microenvironment.


METHODS
We delivered pancreatic pieces into Niobium-Coated Dynamatrix to construct a simulated pancreatic microenvironment, upon which soluble cytokine exchange and direct cell-cell contact between MSCs and pancreatic cells could occur. Bone marrow-derived MSCs were cultured upon the microenvironment. Differentiated isletlike cells were observed under an inverted microscope. Insulin in supernates was measurement by enzyme-linked immunosorbent assay. Insulin and c-peptide expression were verified by fluorescent immunocytochemistry and fluorescence in situ hybridization. Apoptosis of isletlike masses in high-glucose DMEM was detected by FACS.


RESULTS
After 3 to 4 weeks in culture, typical isletlike masses were observed. Insulin secreted by differentiated cells (414.47+/-30.30 mIU/L) was much greater than that of undifferentiated cells (4.89+/-1.01 mIU/L; P<.05). Insulin and c-peptide expression were positive both in protein and mRNA levels. The transdifferentiated isletlike mass did not undergo apoptosis after another 3 weeks of culture in high-glucose DMEM.


CONCLUSIONS
This simulated injury microenvironment without induction guided MSCs to functional isletlike cells hopefully to replace beta cells.
Chang
C
C
Department of Immunology Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
Niu
D
D
Zhou
H
H
Li
F
F
Gong
F
F
D000818:Animals; D002096:C-Peptide / Q000032:analysis; D005269:Femur / Q000502:physiology; D006801:Humans; D007328:Insulin / Q000378:metabolism*; D000078790:Insulin Secretion; D007515:Islets of Langerhans / Q000166:cytology; D045164:Mesenchymal Stem Cell Transplantation; D023421:Models, Animal; D010179:Pancreas / Q000166:cytology; D011817:Rabbits
D002096:C-Peptide; D007328:Insulin