To confirm this effect in isolated human HF keratinocytes, which are not influenced by the HF mesenchyme, HF melanocytes, and intrafollicular hematopoietic cells, we measured the steady-state levels of K15 mRNA in cultured human ORS keratinocytes that had been treated for 48 h with 0.5 μM spermidine. Here, KRT15 is linked to hydrops fetalis.