Derivation of Equine Mesenchymal Stem/Stromal Cells from Induced Pluripotent Stem Cells via the Neural Crest Pathway and Characterisation by Immunophenotype and Tri-Lineage Differentiation.

Overview

• This study explores a new method to generate mesenchymal stem/stromal cells (MSCs) from equine induced pluripotent stem cells (eqiPSCs) by guiding their differentiation through the neural crest pathway.
• The derived cells, called eqiMSCs, were characterized and compared to traditional tissue-derived MSCs to assess their potential for veterinary therapeutic use.

Background and Rationale

• Mesenchymal stem/stromal cells (MSCs) have therapeutic potential in treating various horse (equine) diseases and injuries.
• However, MSCs from traditional tissue sources undergo senescence (loss of growth capacity) during culture, limiting their availability and potential for repeated use.
• Induced pluripotent stem cells (iPSCs) are an alternative cell source that can proliferate extensively and potentially be directed to differentiate into MSC-like cells (iMSCs), addressing cell availability issues.
• In humans, iMSC derivation and application have been extensively studied, but in horses, research is limited and has largely focused on spontaneous differentiation rather than directed differentiation protocols.

Research Aim

• The main goal was to derive MSC-like cells from equine iPSCs (eqiPSCs) using controlled differentiation through the neural crest pathway.
• The neural crest pathway is a developmental route that embryonic cells take to become various cell types, including ones with MSC-like characteristics.

Methodology

• Equine iPSCs were cultured and induced to differentiate specifically through the neural crest lineage rather than allowing random or spontaneous differentiation.
• Derived cells (eqiMSCs) were analyzed for key properties:
• Expression levels of pluripotency genes to confirm loss of stemness.
• Immunophenotype, meaning their surface markers were checked to see if they match MSC characteristics.
• Tri-lineage differentiation potential, testing their ability to become bone, cartilage, and fat cells, which is a hallmark of MSC identity.

Key Findings

• eqiMSCs showed downregulation of pluripotency genes compared to the parent eqiPSCs, indicating successful differentiation.
• Most eqiMSC lines met the standard criteria for MSCs based on immunophenotypic markers and the ability to differentiate into bone, cartilage, and fat cells.
• Despite similarities, eqiMSCs displayed differences from primary tissue-derived equine MSCs, which may be due to their distinct developmental origin via the neural crest pathway.
• There was variability among different eqiMSC lines, possibly related to intrinsic differences in the kinetics and characteristics of the originating eqiPSC lines.

Significance and Implications

• This study is the first to demonstrate the feasibility of deriving equine MSC-like cells from eqiPSCs through a directed neural crest differentiation protocol.
• This approach offers a sustainable and less invasive source of therapeutic cells for veterinary medicine, as it could reduce the need for repeated tissue biopsies.
• While promising, the functional features and therapeutic efficacy of these eqiMSCs require further investigation to fully understand their potential and any differences from primary MSCs.
• Overall, this research provides a valuable foundation for advancing cell-based therapies in horses using stem cell technologies.