In the final version of our recent paper [1], one of the authors was erroneously removed from the list of authors. The correct list of authors comprises G. Godeau, Paris V University, 1 rue Maurice Arnoux, 91 120 Montrouge, France, at the 4^th position.

In addition, one paragraph is missing in Section 2.1. This section should read:

2.1 Keratin and skin biopsy material

Purified keratin from human epidermis [2] was purchased from Sigma-Aldrich as a 30 mg/mL solution in urea (product K0253, solution in 8 M urea, 50 mM Tris, 0.1 Mb-mercaptoethanol and 0.1% sodium azide). The purification process resulted in a mixture of various cytokeratins as illustrated by the electrophoresis analysis showing several bands in the 45 to 60 kDa range. The keratin solution was studied in a 100 μm optical path fused silica microcell (QS-106, Hellma).

The control healthy patient included in this study (female aged 30) had neither skin nor systemic diseases and had not taken preoperative medication. Skin biopsy was obtained under local anaesthesia avoiding local anaesthetic infiltration into the biopsy site and deformation or compression of the sample. Informed consent for the biopsy was obtained from the patient according to Helsinki rules. Tissue sample was fixed for 96 hours in paraformaldehyde (4 %) and then embedded in paraffin. Serial skin tissue sections, 6 μm thick were prepared with a manual microtome.