Human mesenchymal stem cells protect human islets from pro-inflammatory cytokines.
Transplantation of human islets is an attractive alternative to daily insulin injections for patients with type 1 diabetes. However, the majority of islet recipients lose graft function within five years. Inflammation is a primary contributor to graft loss, and inhibiting pro-inflammatory cytokine activity can reverse inflammation mediated dysfunction of islet grafts. As mesenchymal stem cells (MSCs) possess numerous immunoregulatory properties, we hypothesized that MSCs could protect human islets from pro-inflammatory cytokines. Five hundred human islets were co-cultured with 0.5 or 1.0 × 10(6) human MSCs derived from bone marrow or pancreas for 24 hours followed by 48 hour exposure to interferon-γ, tumor necrosis factor-α and interleukin 1β. Controls include islets cultured alone (± cytokines) and with human dermal fibroblasts (± cytokines). For all conditions, glucose stimulated insulin secretion (GSIS), total islet cellular insulin content, islet β cell apoptosis, and potential cytoprotective factors secreted in the culture media were determined. Cytokine exposure disrupted human islet GSIS based on stimulation index and percentage insulin secretion. Conversely, culture with 1.0 × 10(6) bMSCs preserved GSIS from cytokine treated islets. Protective effects were not observed with fibroblasts, indicating that preservation of human islet GSIS after exposure to pro-inflammatory cytokines is MSC dependent. Islet β cell apoptosis was observed in the presence of cytokines; however, culture of bMSCs with islets prevented β cell apoptosis after cytokine treatment. Hepatocyte growth factor (HGF) as well as matrix metalloproteinases 2 and 9 were also identified as putative secreted cytoprotective factors; however, other secreted factors likely play a role in protection. This study, therefore, demonstrates that MSCs may be beneficial for islet engraftment by promoting cell survival and reduced inflammation.
Department of Surgery, 5-002 Li Ka Shing Centre for Health Research Innovation, University of Alberta, Edmonton, Alberta, Canada.
Telford Y
TY
Yeung
Karen L
KL
Seeberger
Tatsuya
T
Kin
Adetola
A
Adesida
Nadr
N
Jomha
A M James
AM
Shapiro
Gregory S
GS
Korbutt
D000293:Adolescent; D000328:Adult; D000368:Aged; D017209:Apoptosis / Q000187:drug effects; D001854:Bone Marrow Cells / Q000166:cytology; D002449:Cell Aggregation; D018920:Coculture Techniques; D016207:Cytokines / Q000494:pharmacology*; D019610:Cytoprotection / Q000187:drug effects; D005947:Glucose / Q000494:pharmacology; D006085:Graft Survival / Q000187:drug effects; D017228:Hepatocyte Growth Factor / Q000378:metabolism; D006801:Humans; D007249:Inflammation / Q000378:metabolism; D007328:Insulin / Q000378:metabolism; D000078790:Insulin Secretion; D050417:Insulin-Secreting Cells / Q000166:cytology / Q000187:drug effects; D007515:Islets of Langerhans / Q000166:cytology* / Q000187:drug effects* / Q000276:immunology / Q000378:metabolism; D016381:Islets of Langerhans Transplantation; D059630:Mesenchymal Stem Cells / Q000166:cytology*; D008875:Middle Aged; D055815:Young Adult
D016207:Cytokines; D007328:Insulin; D017228:Hepatocyte Growth Factor; D005947:Glucose