Characterization of the hematopoietic niche components. (A) All UCB units were enriched for CD34⁺ cells for this study with >90% purity. (B) Enriched BM MSCs were CD73⁺CD105⁺CD90⁺. (C) UCB CD34⁺ cells were cultured in suspension (i; control), BM MSC monolayer (ii), DWJM (iii), and DWJM preseeded with BM MSCs (iv). (D) Histology hematoxylin and eosin–stained sections of the 2 compartments (Suspension vs Adherent) of 3D DWJM-based culture systems (original magnification ×20). Hematopoietic cells were identified in DWJM (left) and DWJM preseeded with BM MSCs (right), respectively, after 7-day culture in StemSpan with stem cell-supporting cytokines.