A two-dimensional (2-D) gel database of proteins from noncultured total normal human epidermal keratinocytes has been established. A total of 1449 [35S]methionine labelled proteins (1112 isoelectric focusing, 337 nonequilibrium pH gradient electrophoresis) were resolved and recorded using computer assisted (PDQ-SCAN and PDQUEST software) 2-D gel electrophoresis. By matching the protein patterns of total keratinocytes and transformed human amnion cells (master database; Celis et al., Leukemia 1988, 2, 561-602) as well as by 2-D immunoblotting and microsequencing of keratinocyte proteins, it was possible to identify 72 polypeptides in the keratinocyte database. The database also includes data on polypeptides that are synthesized at a higher level by keratinocytes enriched in basal cells, and on six secreted proteins which are produced, albeit at a reduced rate, by normal keratinocytes and that are strongly up-regulated in psoriatic epidermis (Celis et al., FEBS Letters, in press).