Probable interaction between S100A7 and E-FABP in the cytosol of human keratinocytes from psoriatic scales

The overexpression of E-FABP and S100A7 in lesional psoriatic skin suggests a possible link with this hyperproliferative skin disease. In order to inv estigate a role for the proteins in this disease, the purifications for bot h proteins were re-analyzed. Moreover, a specific antiserum directed agains t purified human S100A7 was generated. By SDS-PAGE immunoblotting we show t hat E-FABP and S100A7 are expressed in cultured human differentiating kerat inocytes and confirm their overexpression in psoriatic scales. Gel filtrati on and non-denaturing PAGE revealed that S100A7 co-purified with E-FABP, in dicating an association between the two proteins. Ion-exchange chromatograp hy resulted in the dissociation of the complex. Finally, immunoprecipitatio ns using antiserum against E-FABP revealed that S100A7 co-immunoprecipitate d with E-FABP from protein extracts of psoriatic scales. These data indicat e that E-FABP and S100A7 might form a complex in the cytosol of human kerat inocytes.