The molecular and cellular roles of Psoriasin (S100A4) in human cutaneous wound healing [Abstract]

Our purpose was to determine the role of Psoriasin (S100A7) in keratinocyte proliferation and migration during wound healing. Human keratinocyte cell line HaCaT were transfected with anti-psoriasin ribozyme transgenes constructed in the host laboratories in order to generate a psoriasin-knockdown HaCaT cell line. Together with the respective control cells - HaCat wild type (WT) and HaCat pEF, cellular functions critically involved in wound healing were assessed. These include: cell migration (assessed by ECIS based wounding assays) and colorimetric cell growth assay. RT PCR of the cDNA extracted from the transfected cell lines confirmed successful knock down of psoriasin on comparison with control HaCat WT and pEF. Cell growth assay using crystal violet staining of the cells showed significant (po0.05) increase in the growth rate of cell after psoriasin knockdown atday 0,3 and 5 when compared to both control cell lines. ECIS assay demonstrated more than 35%, 65% and 80% increase in post wounding resistance at 2 hrs, 3 hrs and 4 hrs respectively. Psoriasin is expressed in keratinocytes as seen on RT-PCR and is a fundamental regulator of keratinocyte migration. Significant increase in rate of migration and growth in psoriasin deficient cells, confirm that it has the potential to be a prognostic indicator of the non-healing phenotype and therapeutic targets