Insulin-transferrin-selenium as an alternative to foetal serum for epidermal equivalents.
OBJECTIVE
Organotypic skin models are powerful tools for research in development, ageing and diseases. They have become more and more complex with the use of multiple cell types. This requires a culture medium adapted to optimize the development of such in vitro skin. Foetal bovine serum (FBS) is the most complete supplement in existence at the moment, providing at once growth factors, vitamins, hormones and other circulating compounds. However, this cocktail suffers from batch variability and its animal origin is ethically questionable. More importantly, its biological activities may interfere with the study of certain signalling pathways. Here, we present a strategy for constructing an epidermal equivalent using a defined culture medium without serum.


METHODS
An epidermal equivalent was constructed with primary human keratinocytes cultured using an insulin-transferrin-selenium (ITS) medium. Determination of steady-state gene expression levels and the immunohistological characterization of keratinocyte markers were performed to compare the ITS medium condition with a reference model, where keratinocytes were co-cultured with fibroblasts in the presence of FBS.


RESULTS
The data show that the ITS medium promoted the expression of keratinocyte proliferation and differentiation markers at the protein and transcript levels in a similar way to that of the reference model.


CONCLUSIONS
We show that culture using the ITS medium appears as a viable replacement for FBS in the construction of epidermal equivalents, opening the way to signal transduction studies.
Laboratoire de Biologie Tissulaire et Ingénierie Thérapeutique, CNRS, UMR5305, Université Lyon 1, 7 passage du Vercors, 69367, Lyon, France.
C
C
Mainzer
C
C
Barrichello
R
R
Debret
N
N
Remoué
D
D
Sigaudo-Roussel
P
P
Sommer
D001483:Base Sequence; D002478:Cells, Cultured; D018920:Coculture Techniques; D003470:Culture Media; D016895:Culture Media, Serum-Free; D017931:DNA Primers; D004817:Epidermis; D005312:Fetal Blood; D005455:Fluorescent Antibody Technique; D006801:Humans; D007328:Insulin; D015603:Keratinocytes / Q000166:cytology; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012643:Selenium; D014168:Transferrin
D003470:Culture Media; D016895:Culture Media, Serum-Free; D017931:DNA Primers; D007328:Insulin; D014168:Transferrin; D012643:Selenium
cell culture; epidermal equivalent; insulin-transferrin-selenium; safety testing; serum free; skin physiology/structure