In the present study the cellular distribution of the inducible (hsp72) and constitutive (hsc73) forms of human 70 kD heat shock protein was evaluated. A weak reactivity of the anti-hsp72/hsc73 MoAb was found in the cytoplasm of the unstressed human epidermal cells, while stressed cells showed an enhanced reactivity at the cytoplasmic level and the expression of the molecules on the cell surface. Moreover, the antigenic properties of the two proteins were investigated by sequence analysis. Our findings provided evidence for at least three regions in the hsp72 which can be considered good candidates to represent T-immunogenic antigens. This data as well as the cell surface localization of the hsp72, could suggest an antigenic role of the hsp72.