Letter to the Editor: Advancing induced pluripotent stem cell-derived mesenchymal stem cells - insights from comparative differentiation protocols and emerging innovations

Table 2 A three-tier potency assay

Tier	Assay category	Specific metrics (thresholds)
Phenotypic core	Surface + lineage transcription	CD73/CD90/CD105 ≥ 95%
		RUNX2 ≥ 2.5-fold vs BM-MSC (qPCR)
		PPARG ≤ 0.5-fold
Functional potency	Proliferation, migration, stress resilience	CFU-F ≥ 50/103 cells
		Transwell migration index ≥ 0.7 (24 hours)
		ROS ≤ 60% BM-MSC baseline (DCFDA)
Translational predictors	3D microenvironment + AI modeling	3D spheroid invasion ≥ 70% (72 hours, Matrigel)
		AI-predicted batch consistency (R2 ≥ 0.85 via scRNA-seq input)

RUNX2: Runt-related transcription factor 2; BM-MSC: Bone marrow mesenchymal stem cell; qPCR: Quantitative polymerase chain reaction; PPARG: Peroxisome proliferator-activated receptor gamma; CFU-F: Colony forming units-fibroblast; ROS: Reactive oxygen species; DCFDA: 2’,7’-dichlorofluorescin diacetate; AI: Artificial intelligence; scRNA-seq: Single-cell RNA sequencing.