Induction of the low-molecular-weight stress protein HSP27 in organ-cultured normal human skin.

To examine the inducibility of 27-kD-molecular-weight heat shock protein (HSP27) in human skin, an indirect immunofluorescence (IF) study was performed on organ-cultured normal human skin by using a monoclonal antibody specific for HSP27. After heat treatment at 45 degrees C for 1 h, nuclear IF was observed in the epidermal cells. When the organ-cultured skin explants were exposed to 10.0 micrograms/ml or 100.0 micrograms/ml 8-methoxypsoralen (8-MOP) for 1 h and then irradiated with UVA (320-400 nm), positive nuclear IF was also observed 6 h after UVA irradiation. Considering these results with the previous reports about HSP72, it appears that, in human skin, HSP27 as well as HSP72 plays an important role in resisting various environmental stresses.