Dermal Papilla Cells & Inductive Signaling
Dermal papilla cells expanded as 3D spheroids to preserve inductive signature (ALP⁺, versican⁺, corin⁺) and rescue hair-inductive capacity lost in 2D.
Dermal papilla (DP) cells are microdissected from donor follicles, dispase-released, and seeded on low-attachment U-bottom plates at 3000 cells/well to form spheroids (Ø ≈ 180 µm by 72 h). Spheroid culture mitigates the well-documented loss of inductivity that DP cells suffer in monolayer past P2 — the spheroid state restores >70 % of the native ALP⁺ / versican⁺ / corin⁺ signature.
Inductivity is functionally validated by a co-graft assay: DP spheroids + neonatal keratinocytes implanted into NSG-mouse silicone chambers must produce ≥ 8 pigmented hair shafts per chamber at day 21 before clinical use.
| Parameter | Value | Unit | Tolerance / Note |
|---|---|---|---|
| Source | Autologous donor follicles | ||
| Spheroid size | 180 | µm | 3000 cells/well, 72 h |
| Inductive markers | ALP, versican, corin, α-SMA | ||
| Inductivity restoration | ≥ 70 | % native signature | |
| Co-graft validation | ≥ 8 shafts / chamber | NSG mouse, day 21 | |
| Passage limit | ≤ P3 (2D) / P6 (spheroid) |