Human mesenchymal stem cells protect human islets from pro-inflammatory cytokines

Area of Science:

• Immunology
• Endocrinology
• Regenerative Medicine

Background:

• Type 1 diabetes management often involves insulin injections.
• Human islet transplantation offers an alternative but faces challenges with graft loss.
• Inflammation-induced graft dysfunction is a major cause of islet transplant failure.

Purpose of the Study:

• To investigate the protective effects of mesenchymal stem cells (MSCs) against pro-inflammatory cytokines on human islets.
• To determine if MSCs can preserve islet function and viability under inflammatory conditions.

Main Methods:

• Human islets were co-cultured with bone marrow-derived MSCs or human dermal fibroblasts.
• Cultures were exposed to a mixture of pro-inflammatory cytokines (interferon-γ, tumor necrosis factor-α, interleukin 1β).
• Glucose-stimulated insulin secretion (GSIS), beta cell apoptosis, and secreted factors were assessed.

Main Results:

• Cytokine exposure significantly impaired human islet GSIS and increased beta cell apoptosis.
• Co-culture with 1.0 × 10^6 bone marrow-derived MSCs preserved GSIS and prevented apoptosis.
• Fibroblast co-culture did not provide similar protective effects, highlighting MSC specificity.
• Hepatocyte growth factor (HGF) and matrix metalloproteinases (MMPs) were identified as potential protective factors.

Conclusions:

• Mesenchymal stem cells (MSCs) demonstrate significant potential in protecting human islets from inflammatory damage.
• MSC-mediated protection involves preserving beta cell function (GSIS) and reducing apoptosis.
• These findings suggest MSCs could be a valuable therapeutic strategy to improve outcomes of islet transplantation for type 1 diabetes.