Anna Domogatskaya, PhD
MBB, Karolinska Institute
Biologically relevant laminins enable mouse pancreatic islets in vitro culture: expansion, phenotype maintenance and glucose-dependent insulin release
BACKGROUND: Insulin-producing beta islets are successfully used for treatment Diabetes type I, however, there is a drastic shortage in human donor-derived islet material. Whole islet transplantation has several advantages: (1) beta cells maintain original niche, (2) beta cells maintain contact with vascular endothelial cells, (3) beta cells remain as syncytium, which enables synergy between beta cells within one islet.
QUESTION: Can we maintain the natural niche and syncytium-like organization of beta cells within islet using biologically relevant laminins?
OUR APPROACH: We used several laminins that constitute the natural niche of beta cells in vivo and screened combinations of those as coatings for culturing mouse beta islets. The methods involve screening of growth factors, medium and coating materials combinations, high-throughput automated imaging screening, 3D rendering multicell population analysis and quantification, quantitative RT-PCR and functional protein release quantification.
RESULTS: Mouse islets, when cultured upon selected combination of islet-specific laminins, exhibited following effects: (1) robust spreading into flattened adherent clusters with heterocellular organization maintaining local cell contacts, (2) islets, cultured upon the selected combination, maintain functional ability for glucose-dependent insulin release, (3) all the endocrine cell types (alpha, beta, delta, PP-cels) maintain specific markers expression (glucagon, insulin/C-peptide/PDX-1, somatostatin, pancreatic polypeptide) and ability to proliferate.